Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

16 files changed, 9940 insertions, 0 deletions

diff --git a/arch/mips/kvm/Kconfig b/arch/mips/kvm/Kconfig
new file mode 100644
index 000000000..a8cdba75f
--- /dev/null
+++ b/arch/mips/kvm/Kconfig
@@ -0,0 +1,44 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# KVM configuration
+#
+source "virt/kvm/Kconfig"
+
+menuconfig VIRTUALIZATION
+	bool "Virtualization"
+	help
+	  Say Y here to get to see options for using your Linux host to run
+	  other operating systems inside virtual machines (guests).
+	  This option alone does not add any kernel code.
+
+	  If you say N, all options in this submenu will be skipped and disabled.
+
+if VIRTUALIZATION
+
+config KVM
+	tristate "Kernel-based Virtual Machine (KVM) support"
+	depends on HAVE_KVM
+	depends on MIPS_FP_SUPPORT
+	select EXPORT_UASM
+	select PREEMPT_NOTIFIERS
+	select KVM_GENERIC_DIRTYLOG_READ_PROTECT
+	select HAVE_KVM_EVENTFD
+	select HAVE_KVM_VCPU_ASYNC_IOCTL
+	select KVM_MMIO
+	select MMU_NOTIFIER
+	select INTERVAL_TREE
+	select KVM_GENERIC_HARDWARE_ENABLING
+	help
+	  Support for hosting Guest kernels.
+
+config KVM_MIPS_DEBUG_COP0_COUNTERS
+	bool "Maintain counters for COP0 accesses"
+	depends on KVM
+	help
+	  Maintain statistics for Guest COP0 accesses.
+	  A histogram of COP0 accesses is printed when the VM is
+	  shutdown.
+
+	  If unsure, say N.
+
+endif # VIRTUALIZATION
diff --git a/arch/mips/kvm/Makefile b/arch/mips/kvm/Makefile
new file mode 100644
index 000000000..805aeea21
--- /dev/null
+++ b/arch/mips/kvm/Makefile
@@ -0,0 +1,20 @@
+# SPDX-License-Identifier: GPL-2.0
+# Makefile for KVM support for MIPS
+#
+
+include $(srctree)/virt/kvm/Makefile.kvm
+
+ccflags-y += -Ivirt/kvm -Iarch/mips/kvm
+
+kvm-$(CONFIG_CPU_HAS_MSA) += msa.o
+
+kvm-y +=    mips.o emulate.o entry.o \
+	    interrupt.o stats.o \
+	    fpu.o
+kvm-y += hypcall.o
+kvm-y += mmu.o
+kvm-$(CONFIG_CPU_LOONGSON64) += loongson_ipi.o
+
+kvm-y		+= vz.o
+obj-$(CONFIG_KVM)	+= kvm.o
+obj-y			+= tlb.o
diff --git a/arch/mips/kvm/emulate.c b/arch/mips/kvm/emulate.c
new file mode 100644
index 000000000..e64372b8f
--- /dev/null
+++ b/arch/mips/kvm/emulate.c
@@ -0,0 +1,1650 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * KVM/MIPS: Instruction/Exception emulation
+ *
+ * Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.
+ * Authors: Sanjay Lal <sanjayl@kymasys.com>
+ */
+
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/ktime.h>
+#include <linux/kvm_host.h>
+#include <linux/vmalloc.h>
+#include <linux/fs.h>
+#include <linux/memblock.h>
+#include <linux/random.h>
+#include <asm/page.h>
+#include <asm/cacheflush.h>
+#include <asm/cacheops.h>
+#include <asm/cpu-info.h>
+#include <asm/mmu_context.h>
+#include <asm/tlbflush.h>
+#include <asm/inst.h>
+
+#undef CONFIG_MIPS_MT
+#include <asm/r4kcache.h>
+#define CONFIG_MIPS_MT
+
+#include "interrupt.h"
+
+#include "trace.h"
+
+/*
+ * Compute the return address and do emulate branch simulation, if required.
+ * This function should be called only in branch delay slot active.
+ */
+static int kvm_compute_return_epc(struct kvm_vcpu *vcpu, unsigned long instpc,
+				  unsigned long *out)
+{
+	unsigned int dspcontrol;
+	union mips_instruction insn;
+	struct kvm_vcpu_arch *arch = &vcpu->arch;
+	long epc = instpc;
+	long nextpc;
+	int err;
+
+	if (epc & 3) {
+		kvm_err("%s: unaligned epc\n", __func__);
+		return -EINVAL;
+	}
+
+	/* Read the instruction */
+	err = kvm_get_badinstrp((u32 *)epc, vcpu, &insn.word);
+	if (err)
+		return err;
+
+	switch (insn.i_format.opcode) {
+		/* jr and jalr are in r_format format. */
+	case spec_op:
+		switch (insn.r_format.func) {
+		case jalr_op:
+			arch->gprs[insn.r_format.rd] = epc + 8;
+			fallthrough;
+		case jr_op:
+			nextpc = arch->gprs[insn.r_format.rs];
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+
+		/*
+		 * This group contains:
+		 * bltz_op, bgez_op, bltzl_op, bgezl_op,
+		 * bltzal_op, bgezal_op, bltzall_op, bgezall_op.
+		 */
+	case bcond_op:
+		switch (insn.i_format.rt) {
+		case bltz_op:
+		case bltzl_op:
+			if ((long)arch->gprs[insn.i_format.rs] < 0)
+				epc = epc + 4 + (insn.i_format.simmediate << 2);
+			else
+				epc += 8;
+			nextpc = epc;
+			break;
+
+		case bgez_op:
+		case bgezl_op:
+			if ((long)arch->gprs[insn.i_format.rs] >= 0)
+				epc = epc + 4 + (insn.i_format.simmediate << 2);
+			else
+				epc += 8;
+			nextpc = epc;
+			break;
+
+		case bltzal_op:
+		case bltzall_op:
+			arch->gprs[31] = epc + 8;
+			if ((long)arch->gprs[insn.i_format.rs] < 0)
+				epc = epc + 4 + (insn.i_format.simmediate << 2);
+			else
+				epc += 8;
+			nextpc = epc;
+			break;
+
+		case bgezal_op:
+		case bgezall_op:
+			arch->gprs[31] = epc + 8;
+			if ((long)arch->gprs[insn.i_format.rs] >= 0)
+				epc = epc + 4 + (insn.i_format.simmediate << 2);
+			else
+				epc += 8;
+			nextpc = epc;
+			break;
+		case bposge32_op:
+			if (!cpu_has_dsp) {
+				kvm_err("%s: DSP branch but not DSP ASE\n",
+					__func__);
+				return -EINVAL;
+			}
+
+			dspcontrol = rddsp(0x01);
+
+			if (dspcontrol >= 32)
+				epc = epc + 4 + (insn.i_format.simmediate << 2);
+			else
+				epc += 8;
+			nextpc = epc;
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+
+		/* These are unconditional and in j_format. */
+	case jal_op:
+		arch->gprs[31] = instpc + 8;
+		fallthrough;
+	case j_op:
+		epc += 4;
+		epc >>= 28;
+		epc <<= 28;
+		epc |= (insn.j_format.target << 2);
+		nextpc = epc;
+		break;
+
+		/* These are conditional and in i_format. */
+	case beq_op:
+	case beql_op:
+		if (arch->gprs[insn.i_format.rs] ==
+		    arch->gprs[insn.i_format.rt])
+			epc = epc + 4 + (insn.i_format.simmediate << 2);
+		else
+			epc += 8;
+		nextpc = epc;
+		break;
+
+	case bne_op:
+	case bnel_op:
+		if (arch->gprs[insn.i_format.rs] !=
+		    arch->gprs[insn.i_format.rt])
+			epc = epc + 4 + (insn.i_format.simmediate << 2);
+		else
+			epc += 8;
+		nextpc = epc;
+		break;
+
+	case blez_op:	/* POP06 */
+#ifndef CONFIG_CPU_MIPSR6
+	case blezl_op:	/* removed in R6 */
+#endif
+		if (insn.i_format.rt != 0)
+			goto compact_branch;
+		if ((long)arch->gprs[insn.i_format.rs] <= 0)
+			epc = epc + 4 + (insn.i_format.simmediate << 2);
+		else
+			epc += 8;
+		nextpc = epc;
+		break;
+
+	case bgtz_op:	/* POP07 */
+#ifndef CONFIG_CPU_MIPSR6
+	case bgtzl_op:	/* removed in R6 */
+#endif
+		if (insn.i_format.rt != 0)
+			goto compact_branch;
+		if ((long)arch->gprs[insn.i_format.rs] > 0)
+			epc = epc + 4 + (insn.i_format.simmediate << 2);
+		else
+			epc += 8;
+		nextpc = epc;
+		break;
+
+		/* And now the FPA/cp1 branch instructions. */
+	case cop1_op:
+		kvm_err("%s: unsupported cop1_op\n", __func__);
+		return -EINVAL;
+
+#ifdef CONFIG_CPU_MIPSR6
+	/* R6 added the following compact branches with forbidden slots */
+	case blezl_op:	/* POP26 */
+	case bgtzl_op:	/* POP27 */
+		/* only rt == 0 isn't compact branch */
+		if (insn.i_format.rt != 0)
+			goto compact_branch;
+		return -EINVAL;
+	case pop10_op:
+	case pop30_op:
+		/* only rs == rt == 0 is reserved, rest are compact branches */
+		if (insn.i_format.rs != 0 || insn.i_format.rt != 0)
+			goto compact_branch;
+		return -EINVAL;
+	case pop66_op:
+	case pop76_op:
+		/* only rs == 0 isn't compact branch */
+		if (insn.i_format.rs != 0)
+			goto compact_branch;
+		return -EINVAL;
+compact_branch:
+		/*
+		 * If we've hit an exception on the forbidden slot, then
+		 * the branch must not have been taken.
+		 */
+		epc += 8;
+		nextpc = epc;
+		break;
+#else
+compact_branch:
+		/* Fall through - Compact branches not supported before R6 */
+#endif
+	default:
+		return -EINVAL;
+	}
+
+	*out = nextpc;
+	return 0;
+}
+
+enum emulation_result update_pc(struct kvm_vcpu *vcpu, u32 cause)
+{
+	int err;
+
+	if (cause & CAUSEF_BD) {
+		err = kvm_compute_return_epc(vcpu, vcpu->arch.pc,
+					     &vcpu->arch.pc);
+		if (err)
+			return EMULATE_FAIL;
+	} else {
+		vcpu->arch.pc += 4;
+	}
+
+	kvm_debug("update_pc(): New PC: %#lx\n", vcpu->arch.pc);
+
+	return EMULATE_DONE;
+}
+
+/**
+ * kvm_get_badinstr() - Get bad instruction encoding.
+ * @opc:	Guest pointer to faulting instruction.
+ * @vcpu:	KVM VCPU information.
+ *
+ * Gets the instruction encoding of the faulting instruction, using the saved
+ * BadInstr register value if it exists, otherwise falling back to reading guest
+ * memory at @opc.
+ *
+ * Returns:	The instruction encoding of the faulting instruction.
+ */
+int kvm_get_badinstr(u32 *opc, struct kvm_vcpu *vcpu, u32 *out)
+{
+	if (cpu_has_badinstr) {
+		*out = vcpu->arch.host_cp0_badinstr;
+		return 0;
+	} else {
+		WARN_ONCE(1, "CPU doesn't have BadInstr register\n");
+		return -EINVAL;
+	}
+}
+
+/**
+ * kvm_get_badinstrp() - Get bad prior instruction encoding.
+ * @opc:	Guest pointer to prior faulting instruction.
+ * @vcpu:	KVM VCPU information.
+ *
+ * Gets the instruction encoding of the prior faulting instruction (the branch
+ * containing the delay slot which faulted), using the saved BadInstrP register
+ * value if it exists, otherwise falling back to reading guest memory at @opc.
+ *
+ * Returns:	The instruction encoding of the prior faulting instruction.
+ */
+int kvm_get_badinstrp(u32 *opc, struct kvm_vcpu *vcpu, u32 *out)
+{
+	if (cpu_has_badinstrp) {
+		*out = vcpu->arch.host_cp0_badinstrp;
+		return 0;
+	} else {
+		WARN_ONCE(1, "CPU doesn't have BadInstrp register\n");
+		return -EINVAL;
+	}
+}
+
+/**
+ * kvm_mips_count_disabled() - Find whether the CP0_Count timer is disabled.
+ * @vcpu:	Virtual CPU.
+ *
+ * Returns:	1 if the CP0_Count timer is disabled by either the guest
+ *		CP0_Cause.DC bit or the count_ctl.DC bit.
+ *		0 otherwise (in which case CP0_Count timer is running).
+ */
+int kvm_mips_count_disabled(struct kvm_vcpu *vcpu)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+
+	return	(vcpu->arch.count_ctl & KVM_REG_MIPS_COUNT_CTL_DC) ||
+		(kvm_read_c0_guest_cause(cop0) & CAUSEF_DC);
+}
+
+/**
+ * kvm_mips_ktime_to_count() - Scale ktime_t to a 32-bit count.
+ *
+ * Caches the dynamic nanosecond bias in vcpu->arch.count_dyn_bias.
+ *
+ * Assumes !kvm_mips_count_disabled(@vcpu) (guest CP0_Count timer is running).
+ */
+static u32 kvm_mips_ktime_to_count(struct kvm_vcpu *vcpu, ktime_t now)
+{
+	s64 now_ns, periods;
+	u64 delta;
+
+	now_ns = ktime_to_ns(now);
+	delta = now_ns + vcpu->arch.count_dyn_bias;
+
+	if (delta >= vcpu->arch.count_period) {
+		/* If delta is out of safe range the bias needs adjusting */
+		periods = div64_s64(now_ns, vcpu->arch.count_period);
+		vcpu->arch.count_dyn_bias = -periods * vcpu->arch.count_period;
+		/* Recalculate delta with new bias */
+		delta = now_ns + vcpu->arch.count_dyn_bias;
+	}
+
+	/*
+	 * We've ensured that:
+	 *   delta < count_period
+	 *
+	 * Therefore the intermediate delta*count_hz will never overflow since
+	 * at the boundary condition:
+	 *   delta = count_period
+	 *   delta = NSEC_PER_SEC * 2^32 / count_hz
+	 *   delta * count_hz = NSEC_PER_SEC * 2^32
+	 */
+	return div_u64(delta * vcpu->arch.count_hz, NSEC_PER_SEC);
+}
+
+/**
+ * kvm_mips_count_time() - Get effective current time.
+ * @vcpu:	Virtual CPU.
+ *
+ * Get effective monotonic ktime. This is usually a straightforward ktime_get(),
+ * except when the master disable bit is set in count_ctl, in which case it is
+ * count_resume, i.e. the time that the count was disabled.
+ *
+ * Returns:	Effective monotonic ktime for CP0_Count.
+ */
+static inline ktime_t kvm_mips_count_time(struct kvm_vcpu *vcpu)
+{
+	if (unlikely(vcpu->arch.count_ctl & KVM_REG_MIPS_COUNT_CTL_DC))
+		return vcpu->arch.count_resume;
+
+	return ktime_get();
+}
+
+/**
+ * kvm_mips_read_count_running() - Read the current count value as if running.
+ * @vcpu:	Virtual CPU.
+ * @now:	Kernel time to read CP0_Count at.
+ *
+ * Returns the current guest CP0_Count register at time @now and handles if the
+ * timer interrupt is pending and hasn't been handled yet.
+ *
+ * Returns:	The current value of the guest CP0_Count register.
+ */
+static u32 kvm_mips_read_count_running(struct kvm_vcpu *vcpu, ktime_t now)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+	ktime_t expires, threshold;
+	u32 count, compare;
+	int running;
+
+	/* Calculate the biased and scaled guest CP0_Count */
+	count = vcpu->arch.count_bias + kvm_mips_ktime_to_count(vcpu, now);
+	compare = kvm_read_c0_guest_compare(cop0);
+
+	/*
+	 * Find whether CP0_Count has reached the closest timer interrupt. If
+	 * not, we shouldn't inject it.
+	 */
+	if ((s32)(count - compare) < 0)
+		return count;
+
+	/*
+	 * The CP0_Count we're going to return has already reached the closest
+	 * timer interrupt. Quickly check if it really is a new interrupt by
+	 * looking at whether the interval until the hrtimer expiry time is
+	 * less than 1/4 of the timer period.
+	 */
+	expires = hrtimer_get_expires(&vcpu->arch.comparecount_timer);
+	threshold = ktime_add_ns(now, vcpu->arch.count_period / 4);
+	if (ktime_before(expires, threshold)) {
+		/*
+		 * Cancel it while we handle it so there's no chance of
+		 * interference with the timeout handler.
+		 */
+		running = hrtimer_cancel(&vcpu->arch.comparecount_timer);
+
+		/* Nothing should be waiting on the timeout */
+		kvm_mips_callbacks->queue_timer_int(vcpu);
+
+		/*
+		 * Restart the timer if it was running based on the expiry time
+		 * we read, so that we don't push it back 2 periods.
+		 */
+		if (running) {
+			expires = ktime_add_ns(expires,
+					       vcpu->arch.count_period);
+			hrtimer_start(&vcpu->arch.comparecount_timer, expires,
+				      HRTIMER_MODE_ABS);
+		}
+	}
+
+	return count;
+}
+
+/**
+ * kvm_mips_read_count() - Read the current count value.
+ * @vcpu:	Virtual CPU.
+ *
+ * Read the current guest CP0_Count value, taking into account whether the timer
+ * is stopped.
+ *
+ * Returns:	The current guest CP0_Count value.
+ */
+u32 kvm_mips_read_count(struct kvm_vcpu *vcpu)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+
+	/* If count disabled just read static copy of count */
+	if (kvm_mips_count_disabled(vcpu))
+		return kvm_read_c0_guest_count(cop0);
+
+	return kvm_mips_read_count_running(vcpu, ktime_get());
+}
+
+/**
+ * kvm_mips_freeze_hrtimer() - Safely stop the hrtimer.
+ * @vcpu:	Virtual CPU.
+ * @count:	Output pointer for CP0_Count value at point of freeze.
+ *
+ * Freeze the hrtimer safely and return both the ktime and the CP0_Count value
+ * at the point it was frozen. It is guaranteed that any pending interrupts at
+ * the point it was frozen are handled, and none after that point.
+ *
+ * This is useful where the time/CP0_Count is needed in the calculation of the
+ * new parameters.
+ *
+ * Assumes !kvm_mips_count_disabled(@vcpu) (guest CP0_Count timer is running).
+ *
+ * Returns:	The ktime at the point of freeze.
+ */
+ktime_t kvm_mips_freeze_hrtimer(struct kvm_vcpu *vcpu, u32 *count)
+{
+	ktime_t now;
+
+	/* stop hrtimer before finding time */
+	hrtimer_cancel(&vcpu->arch.comparecount_timer);
+	now = ktime_get();
+
+	/* find count at this point and handle pending hrtimer */
+	*count = kvm_mips_read_count_running(vcpu, now);
+
+	return now;
+}
+
+/**
+ * kvm_mips_resume_hrtimer() - Resume hrtimer, updating expiry.
+ * @vcpu:	Virtual CPU.
+ * @now:	ktime at point of resume.
+ * @count:	CP0_Count at point of resume.
+ *
+ * Resumes the timer and updates the timer expiry based on @now and @count.
+ * This can be used in conjunction with kvm_mips_freeze_timer() when timer
+ * parameters need to be changed.
+ *
+ * It is guaranteed that a timer interrupt immediately after resume will be
+ * handled, but not if CP_Compare is exactly at @count. That case is already
+ * handled by kvm_mips_freeze_timer().
+ *
+ * Assumes !kvm_mips_count_disabled(@vcpu) (guest CP0_Count timer is running).
+ */
+static void kvm_mips_resume_hrtimer(struct kvm_vcpu *vcpu,
+				    ktime_t now, u32 count)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+	u32 compare;
+	u64 delta;
+	ktime_t expire;
+
+	/* Calculate timeout (wrap 0 to 2^32) */
+	compare = kvm_read_c0_guest_compare(cop0);
+	delta = (u64)(u32)(compare - count - 1) + 1;
+	delta = div_u64(delta * NSEC_PER_SEC, vcpu->arch.count_hz);
+	expire = ktime_add_ns(now, delta);
+
+	/* Update hrtimer to use new timeout */
+	hrtimer_cancel(&vcpu->arch.comparecount_timer);
+	hrtimer_start(&vcpu->arch.comparecount_timer, expire, HRTIMER_MODE_ABS);
+}
+
+/**
+ * kvm_mips_restore_hrtimer() - Restore hrtimer after a gap, updating expiry.
+ * @vcpu:	Virtual CPU.
+ * @before:	Time before Count was saved, lower bound of drift calculation.
+ * @count:	CP0_Count at point of restore.
+ * @min_drift:	Minimum amount of drift permitted before correction.
+ *		Must be <= 0.
+ *
+ * Restores the timer from a particular @count, accounting for drift. This can
+ * be used in conjunction with kvm_mips_freeze_timer() when a hardware timer is
+ * to be used for a period of time, but the exact ktime corresponding to the
+ * final Count that must be restored is not known.
+ *
+ * It is gauranteed that a timer interrupt immediately after restore will be
+ * handled, but not if CP0_Compare is exactly at @count. That case should
+ * already be handled when the hardware timer state is saved.
+ *
+ * Assumes !kvm_mips_count_disabled(@vcpu) (guest CP0_Count timer is not
+ * stopped).
+ *
+ * Returns:	Amount of correction to count_bias due to drift.
+ */
+int kvm_mips_restore_hrtimer(struct kvm_vcpu *vcpu, ktime_t before,
+			     u32 count, int min_drift)
+{
+	ktime_t now, count_time;
+	u32 now_count, before_count;
+	u64 delta;
+	int drift, ret = 0;
+
+	/* Calculate expected count at before */
+	before_count = vcpu->arch.count_bias +
+			kvm_mips_ktime_to_count(vcpu, before);
+
+	/*
+	 * Detect significantly negative drift, where count is lower than
+	 * expected. Some negative drift is expected when hardware counter is
+	 * set after kvm_mips_freeze_timer(), and it is harmless to allow the
+	 * time to jump forwards a little, within reason. If the drift is too
+	 * significant, adjust the bias to avoid a big Guest.CP0_Count jump.
+	 */
+	drift = count - before_count;
+	if (drift < min_drift) {
+		count_time = before;
+		vcpu->arch.count_bias += drift;
+		ret = drift;
+		goto resume;
+	}
+
+	/* Calculate expected count right now */
+	now = ktime_get();
+	now_count = vcpu->arch.count_bias + kvm_mips_ktime_to_count(vcpu, now);
+
+	/*
+	 * Detect positive drift, where count is higher than expected, and
+	 * adjust the bias to avoid guest time going backwards.
+	 */
+	drift = count - now_count;
+	if (drift > 0) {
+		count_time = now;
+		vcpu->arch.count_bias += drift;
+		ret = drift;
+		goto resume;
+	}
+
+	/* Subtract nanosecond delta to find ktime when count was read */
+	delta = (u64)(u32)(now_count - count);
+	delta = div_u64(delta * NSEC_PER_SEC, vcpu->arch.count_hz);
+	count_time = ktime_sub_ns(now, delta);
+
+resume:
+	/* Resume using the calculated ktime */
+	kvm_mips_resume_hrtimer(vcpu, count_time, count);
+	return ret;
+}
+
+/**
+ * kvm_mips_write_count() - Modify the count and update timer.
+ * @vcpu:	Virtual CPU.
+ * @count:	Guest CP0_Count value to set.
+ *
+ * Sets the CP0_Count value and updates the timer accordingly.
+ */
+void kvm_mips_write_count(struct kvm_vcpu *vcpu, u32 count)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+	ktime_t now;
+
+	/* Calculate bias */
+	now = kvm_mips_count_time(vcpu);
+	vcpu->arch.count_bias = count - kvm_mips_ktime_to_count(vcpu, now);
+
+	if (kvm_mips_count_disabled(vcpu))
+		/* The timer's disabled, adjust the static count */
+		kvm_write_c0_guest_count(cop0, count);
+	else
+		/* Update timeout */
+		kvm_mips_resume_hrtimer(vcpu, now, count);
+}
+
+/**
+ * kvm_mips_init_count() - Initialise timer.
+ * @vcpu:	Virtual CPU.
+ * @count_hz:	Frequency of timer.
+ *
+ * Initialise the timer to the specified frequency, zero it, and set it going if
+ * it's enabled.
+ */
+void kvm_mips_init_count(struct kvm_vcpu *vcpu, unsigned long count_hz)
+{
+	vcpu->arch.count_hz = count_hz;
+	vcpu->arch.count_period = div_u64((u64)NSEC_PER_SEC << 32, count_hz);
+	vcpu->arch.count_dyn_bias = 0;
+
+	/* Starting at 0 */
+	kvm_mips_write_count(vcpu, 0);
+}
+
+/**
+ * kvm_mips_set_count_hz() - Update the frequency of the timer.
+ * @vcpu:	Virtual CPU.
+ * @count_hz:	Frequency of CP0_Count timer in Hz.
+ *
+ * Change the frequency of the CP0_Count timer. This is done atomically so that
+ * CP0_Count is continuous and no timer interrupt is lost.
+ *
+ * Returns:	-EINVAL if @count_hz is out of range.
+ *		0 on success.
+ */
+int kvm_mips_set_count_hz(struct kvm_vcpu *vcpu, s64 count_hz)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+	int dc;
+	ktime_t now;
+	u32 count;
+
+	/* ensure the frequency is in a sensible range... */
+	if (count_hz <= 0 || count_hz > NSEC_PER_SEC)
+		return -EINVAL;
+	/* ... and has actually changed */
+	if (vcpu->arch.count_hz == count_hz)
+		return 0;
+
+	/* Safely freeze timer so we can keep it continuous */
+	dc = kvm_mips_count_disabled(vcpu);
+	if (dc) {
+		now = kvm_mips_count_time(vcpu);
+		count = kvm_read_c0_guest_count(cop0);
+	} else {
+		now = kvm_mips_freeze_hrtimer(vcpu, &count);
+	}
+
+	/* Update the frequency */
+	vcpu->arch.count_hz = count_hz;
+	vcpu->arch.count_period = div_u64((u64)NSEC_PER_SEC << 32, count_hz);
+	vcpu->arch.count_dyn_bias = 0;
+
+	/* Calculate adjusted bias so dynamic count is unchanged */
+	vcpu->arch.count_bias = count - kvm_mips_ktime_to_count(vcpu, now);
+
+	/* Update and resume hrtimer */
+	if (!dc)
+		kvm_mips_resume_hrtimer(vcpu, now, count);
+	return 0;
+}
+
+/**
+ * kvm_mips_write_compare() - Modify compare and update timer.
+ * @vcpu:	Virtual CPU.
+ * @compare:	New CP0_Compare value.
+ * @ack:	Whether to acknowledge timer interrupt.
+ *
+ * Update CP0_Compare to a new value and update the timeout.
+ * If @ack, atomically acknowledge any pending timer interrupt, otherwise ensure
+ * any pending timer interrupt is preserved.
+ */
+void kvm_mips_write_compare(struct kvm_vcpu *vcpu, u32 compare, bool ack)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+	int dc;
+	u32 old_compare = kvm_read_c0_guest_compare(cop0);
+	s32 delta = compare - old_compare;
+	u32 cause;
+	ktime_t now = ktime_set(0, 0); /* silence bogus GCC warning */
+	u32 count;
+
+	/* if unchanged, must just be an ack */
+	if (old_compare == compare) {
+		if (!ack)
+			return;
+		kvm_mips_callbacks->dequeue_timer_int(vcpu);
+		kvm_write_c0_guest_compare(cop0, compare);
+		return;
+	}
+
+	/*
+	 * If guest CP0_Compare moves forward, CP0_GTOffset should be adjusted
+	 * too to prevent guest CP0_Count hitting guest CP0_Compare.
+	 *
+	 * The new GTOffset corresponds to the new value of CP0_Compare, and is
+	 * set prior to it being written into the guest context. We disable
+	 * preemption until the new value is written to prevent restore of a
+	 * GTOffset corresponding to the old CP0_Compare value.
+	 */
+	if (delta > 0) {
+		preempt_disable();
+		write_c0_gtoffset(compare - read_c0_count());
+		back_to_back_c0_hazard();
+	}
+
+	/* freeze_hrtimer() takes care of timer interrupts <= count */
+	dc = kvm_mips_count_disabled(vcpu);
+	if (!dc)
+		now = kvm_mips_freeze_hrtimer(vcpu, &count);
+
+	if (ack)
+		kvm_mips_callbacks->dequeue_timer_int(vcpu);
+	else
+		/*
+		 * With VZ, writing CP0_Compare acks (clears) CP0_Cause.TI, so
+		 * preserve guest CP0_Cause.TI if we don't want to ack it.
+		 */
+		cause = kvm_read_c0_guest_cause(cop0);
+
+	kvm_write_c0_guest_compare(cop0, compare);
+
+	if (delta > 0)
+		preempt_enable();
+
+	back_to_back_c0_hazard();
+
+	if (!ack && cause & CAUSEF_TI)
+		kvm_write_c0_guest_cause(cop0, cause);
+
+	/* resume_hrtimer() takes care of timer interrupts > count */
+	if (!dc)
+		kvm_mips_resume_hrtimer(vcpu, now, count);
+
+	/*
+	 * If guest CP0_Compare is moving backward, we delay CP0_GTOffset change
+	 * until after the new CP0_Compare is written, otherwise new guest
+	 * CP0_Count could hit new guest CP0_Compare.
+	 */
+	if (delta <= 0)
+		write_c0_gtoffset(compare - read_c0_count());
+}
+
+/**
+ * kvm_mips_count_disable() - Disable count.
+ * @vcpu:	Virtual CPU.
+ *
+ * Disable the CP0_Count timer. A timer interrupt on or before the final stop
+ * time will be handled but not after.
+ *
+ * Assumes CP0_Count was previously enabled but now Guest.CP0_Cause.DC or
+ * count_ctl.DC has been set (count disabled).
+ *
+ * Returns:	The time that the timer was stopped.
+ */
+static ktime_t kvm_mips_count_disable(struct kvm_vcpu *vcpu)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+	u32 count;
+	ktime_t now;
+
+	/* Stop hrtimer */
+	hrtimer_cancel(&vcpu->arch.comparecount_timer);
+
+	/* Set the static count from the dynamic count, handling pending TI */
+	now = ktime_get();
+	count = kvm_mips_read_count_running(vcpu, now);
+	kvm_write_c0_guest_count(cop0, count);
+
+	return now;
+}
+
+/**
+ * kvm_mips_count_disable_cause() - Disable count using CP0_Cause.DC.
+ * @vcpu:	Virtual CPU.
+ *
+ * Disable the CP0_Count timer and set CP0_Cause.DC. A timer interrupt on or
+ * before the final stop time will be handled if the timer isn't disabled by
+ * count_ctl.DC, but not after.
+ *
+ * Assumes CP0_Cause.DC is clear (count enabled).
+ */
+void kvm_mips_count_disable_cause(struct kvm_vcpu *vcpu)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+
+	kvm_set_c0_guest_cause(cop0, CAUSEF_DC);
+	if (!(vcpu->arch.count_ctl & KVM_REG_MIPS_COUNT_CTL_DC))
+		kvm_mips_count_disable(vcpu);
+}
+
+/**
+ * kvm_mips_count_enable_cause() - Enable count using CP0_Cause.DC.
+ * @vcpu:	Virtual CPU.
+ *
+ * Enable the CP0_Count timer and clear CP0_Cause.DC. A timer interrupt after
+ * the start time will be handled if the timer isn't disabled by count_ctl.DC,
+ * potentially before even returning, so the caller should be careful with
+ * ordering of CP0_Cause modifications so as not to lose it.
+ *
+ * Assumes CP0_Cause.DC is set (count disabled).
+ */
+void kvm_mips_count_enable_cause(struct kvm_vcpu *vcpu)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+	u32 count;
+
+	kvm_clear_c0_guest_cause(cop0, CAUSEF_DC);
+
+	/*
+	 * Set the dynamic count to match the static count.
+	 * This starts the hrtimer if count_ctl.DC allows it.
+	 * Otherwise it conveniently updates the biases.
+	 */
+	count = kvm_read_c0_guest_count(cop0);
+	kvm_mips_write_count(vcpu, count);
+}
+
+/**
+ * kvm_mips_set_count_ctl() - Update the count control KVM register.
+ * @vcpu:	Virtual CPU.
+ * @count_ctl:	Count control register new value.
+ *
+ * Set the count control KVM register. The timer is updated accordingly.
+ *
+ * Returns:	-EINVAL if reserved bits are set.
+ *		0 on success.
+ */
+int kvm_mips_set_count_ctl(struct kvm_vcpu *vcpu, s64 count_ctl)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+	s64 changed = count_ctl ^ vcpu->arch.count_ctl;
+	s64 delta;
+	ktime_t expire, now;
+	u32 count, compare;
+
+	/* Only allow defined bits to be changed */
+	if (changed & ~(s64)(KVM_REG_MIPS_COUNT_CTL_DC))
+		return -EINVAL;
+
+	/* Apply new value */
+	vcpu->arch.count_ctl = count_ctl;
+
+	/* Master CP0_Count disable */
+	if (changed & KVM_REG_MIPS_COUNT_CTL_DC) {
+		/* Is CP0_Cause.DC already disabling CP0_Count? */
+		if (kvm_read_c0_guest_cause(cop0) & CAUSEF_DC) {
+			if (count_ctl & KVM_REG_MIPS_COUNT_CTL_DC)
+				/* Just record the current time */
+				vcpu->arch.count_resume = ktime_get();
+		} else if (count_ctl & KVM_REG_MIPS_COUNT_CTL_DC) {
+			/* disable timer and record current time */
+			vcpu->arch.count_resume = kvm_mips_count_disable(vcpu);
+		} else {
+			/*
+			 * Calculate timeout relative to static count at resume
+			 * time (wrap 0 to 2^32).
+			 */
+			count = kvm_read_c0_guest_count(cop0);
+			compare = kvm_read_c0_guest_compare(cop0);
+			delta = (u64)(u32)(compare - count - 1) + 1;
+			delta = div_u64(delta * NSEC_PER_SEC,
+					vcpu->arch.count_hz);
+			expire = ktime_add_ns(vcpu->arch.count_resume, delta);
+
+			/* Handle pending interrupt */
+			now = ktime_get();
+			if (ktime_compare(now, expire) >= 0)
+				/* Nothing should be waiting on the timeout */
+				kvm_mips_callbacks->queue_timer_int(vcpu);
+
+			/* Resume hrtimer without changing bias */
+			count = kvm_mips_read_count_running(vcpu, now);
+			kvm_mips_resume_hrtimer(vcpu, now, count);
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * kvm_mips_set_count_resume() - Update the count resume KVM register.
+ * @vcpu:		Virtual CPU.
+ * @count_resume:	Count resume register new value.
+ *
+ * Set the count resume KVM register.
+ *
+ * Returns:	-EINVAL if out of valid range (0..now).
+ *		0 on success.
+ */
+int kvm_mips_set_count_resume(struct kvm_vcpu *vcpu, s64 count_resume)
+{
+	/*
+	 * It doesn't make sense for the resume time to be in the future, as it
+	 * would be possible for the next interrupt to be more than a full
+	 * period in the future.
+	 */
+	if (count_resume < 0 || count_resume > ktime_to_ns(ktime_get()))
+		return -EINVAL;
+
+	vcpu->arch.count_resume = ns_to_ktime(count_resume);
+	return 0;
+}
+
+/**
+ * kvm_mips_count_timeout() - Push timer forward on timeout.
+ * @vcpu:	Virtual CPU.
+ *
+ * Handle an hrtimer event by push the hrtimer forward a period.
+ *
+ * Returns:	The hrtimer_restart value to return to the hrtimer subsystem.
+ */
+enum hrtimer_restart kvm_mips_count_timeout(struct kvm_vcpu *vcpu)
+{
+	/* Add the Count period to the current expiry time */
+	hrtimer_add_expires_ns(&vcpu->arch.comparecount_timer,
+			       vcpu->arch.count_period);
+	return HRTIMER_RESTART;
+}
+
+enum emulation_result kvm_mips_emul_wait(struct kvm_vcpu *vcpu)
+{
+	kvm_debug("[%#lx] !!!WAIT!!! (%#lx)\n", vcpu->arch.pc,
+		  vcpu->arch.pending_exceptions);
+
+	++vcpu->stat.wait_exits;
+	trace_kvm_exit(vcpu, KVM_TRACE_EXIT_WAIT);
+	if (!vcpu->arch.pending_exceptions) {
+		kvm_vz_lose_htimer(vcpu);
+		vcpu->arch.wait = 1;
+		kvm_vcpu_halt(vcpu);
+
+		/*
+		 * We are runnable, then definitely go off to user space to
+		 * check if any I/O interrupts are pending.
+		 */
+		if (kvm_arch_vcpu_runnable(vcpu))
+			vcpu->run->exit_reason = KVM_EXIT_IRQ_WINDOW_OPEN;
+	}
+
+	return EMULATE_DONE;
+}
+
+enum emulation_result kvm_mips_emulate_store(union mips_instruction inst,
+					     u32 cause,
+					     struct kvm_vcpu *vcpu)
+{
+	int r;
+	enum emulation_result er;
+	u32 rt;
+	struct kvm_run *run = vcpu->run;
+	void *data = run->mmio.data;
+	unsigned int imme;
+	unsigned long curr_pc;
+
+	/*
+	 * Update PC and hold onto current PC in case there is
+	 * an error and we want to rollback the PC
+	 */
+	curr_pc = vcpu->arch.pc;
+	er = update_pc(vcpu, cause);
+	if (er == EMULATE_FAIL)
+		return er;
+
+	rt = inst.i_format.rt;
+
+	run->mmio.phys_addr = kvm_mips_callbacks->gva_to_gpa(
+						vcpu->arch.host_cp0_badvaddr);
+	if (run->mmio.phys_addr == KVM_INVALID_ADDR)
+		goto out_fail;
+
+	switch (inst.i_format.opcode) {
+#if defined(CONFIG_64BIT)
+	case sd_op:
+		run->mmio.len = 8;
+		*(u64 *)data = vcpu->arch.gprs[rt];
+
+		kvm_debug("[%#lx] OP_SD: eaddr: %#lx, gpr: %#lx, data: %#llx\n",
+			  vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+			  vcpu->arch.gprs[rt], *(u64 *)data);
+		break;
+#endif
+
+	case sw_op:
+		run->mmio.len = 4;
+		*(u32 *)data = vcpu->arch.gprs[rt];
+
+		kvm_debug("[%#lx] OP_SW: eaddr: %#lx, gpr: %#lx, data: %#x\n",
+			  vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+			  vcpu->arch.gprs[rt], *(u32 *)data);
+		break;
+
+	case sh_op:
+		run->mmio.len = 2;
+		*(u16 *)data = vcpu->arch.gprs[rt];
+
+		kvm_debug("[%#lx] OP_SH: eaddr: %#lx, gpr: %#lx, data: %#x\n",
+			  vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+			  vcpu->arch.gprs[rt], *(u16 *)data);
+		break;
+
+	case sb_op:
+		run->mmio.len = 1;
+		*(u8 *)data = vcpu->arch.gprs[rt];
+
+		kvm_debug("[%#lx] OP_SB: eaddr: %#lx, gpr: %#lx, data: %#x\n",
+			  vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+			  vcpu->arch.gprs[rt], *(u8 *)data);
+		break;
+
+	case swl_op:
+		run->mmio.phys_addr = kvm_mips_callbacks->gva_to_gpa(
+					vcpu->arch.host_cp0_badvaddr) & (~0x3);
+		run->mmio.len = 4;
+		imme = vcpu->arch.host_cp0_badvaddr & 0x3;
+		switch (imme) {
+		case 0:
+			*(u32 *)data = ((*(u32 *)data) & 0xffffff00) |
+					(vcpu->arch.gprs[rt] >> 24);
+			break;
+		case 1:
+			*(u32 *)data = ((*(u32 *)data) & 0xffff0000) |
+					(vcpu->arch.gprs[rt] >> 16);
+			break;
+		case 2:
+			*(u32 *)data = ((*(u32 *)data) & 0xff000000) |
+					(vcpu->arch.gprs[rt] >> 8);
+			break;
+		case 3:
+			*(u32 *)data = vcpu->arch.gprs[rt];
+			break;
+		default:
+			break;
+		}
+
+		kvm_debug("[%#lx] OP_SWL: eaddr: %#lx, gpr: %#lx, data: %#x\n",
+			  vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+			  vcpu->arch.gprs[rt], *(u32 *)data);
+		break;
+
+	case swr_op:
+		run->mmio.phys_addr = kvm_mips_callbacks->gva_to_gpa(
+					vcpu->arch.host_cp0_badvaddr) & (~0x3);
+		run->mmio.len = 4;
+		imme = vcpu->arch.host_cp0_badvaddr & 0x3;
+		switch (imme) {
+		case 0:
+			*(u32 *)data = vcpu->arch.gprs[rt];
+			break;
+		case 1:
+			*(u32 *)data = ((*(u32 *)data) & 0xff) |
+					(vcpu->arch.gprs[rt] << 8);
+			break;
+		case 2:
+			*(u32 *)data = ((*(u32 *)data) & 0xffff) |
+					(vcpu->arch.gprs[rt] << 16);
+			break;
+		case 3:
+			*(u32 *)data = ((*(u32 *)data) & 0xffffff) |
+					(vcpu->arch.gprs[rt] << 24);
+			break;
+		default:
+			break;
+		}
+
+		kvm_debug("[%#lx] OP_SWR: eaddr: %#lx, gpr: %#lx, data: %#x\n",
+			  vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+			  vcpu->arch.gprs[rt], *(u32 *)data);
+		break;
+
+#if defined(CONFIG_64BIT)
+	case sdl_op:
+		run->mmio.phys_addr = kvm_mips_callbacks->gva_to_gpa(
+					vcpu->arch.host_cp0_badvaddr) & (~0x7);
+
+		run->mmio.len = 8;
+		imme = vcpu->arch.host_cp0_badvaddr & 0x7;
+		switch (imme) {
+		case 0:
+			*(u64 *)data = ((*(u64 *)data) & 0xffffffffffffff00) |
+					((vcpu->arch.gprs[rt] >> 56) & 0xff);
+			break;
+		case 1:
+			*(u64 *)data = ((*(u64 *)data) & 0xffffffffffff0000) |
+					((vcpu->arch.gprs[rt] >> 48) & 0xffff);
+			break;
+		case 2:
+			*(u64 *)data = ((*(u64 *)data) & 0xffffffffff000000) |
+					((vcpu->arch.gprs[rt] >> 40) & 0xffffff);
+			break;
+		case 3:
+			*(u64 *)data = ((*(u64 *)data) & 0xffffffff00000000) |
+					((vcpu->arch.gprs[rt] >> 32) & 0xffffffff);
+			break;
+		case 4:
+			*(u64 *)data = ((*(u64 *)data) & 0xffffff0000000000) |
+					((vcpu->arch.gprs[rt] >> 24) & 0xffffffffff);
+			break;
+		case 5:
+			*(u64 *)data = ((*(u64 *)data) & 0xffff000000000000) |
+					((vcpu->arch.gprs[rt] >> 16) & 0xffffffffffff);
+			break;
+		case 6:
+			*(u64 *)data = ((*(u64 *)data) & 0xff00000000000000) |
+					((vcpu->arch.gprs[rt] >> 8) & 0xffffffffffffff);
+			break;
+		case 7:
+			*(u64 *)data = vcpu->arch.gprs[rt];
+			break;
+		default:
+			break;
+		}
+
+		kvm_debug("[%#lx] OP_SDL: eaddr: %#lx, gpr: %#lx, data: %llx\n",
+			  vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+			  vcpu->arch.gprs[rt], *(u64 *)data);
+		break;
+
+	case sdr_op:
+		run->mmio.phys_addr = kvm_mips_callbacks->gva_to_gpa(
+					vcpu->arch.host_cp0_badvaddr) & (~0x7);
+
+		run->mmio.len = 8;
+		imme = vcpu->arch.host_cp0_badvaddr & 0x7;
+		switch (imme) {
+		case 0:
+			*(u64 *)data = vcpu->arch.gprs[rt];
+			break;
+		case 1:
+			*(u64 *)data = ((*(u64 *)data) & 0xff) |
+					(vcpu->arch.gprs[rt] << 8);
+			break;
+		case 2:
+			*(u64 *)data = ((*(u64 *)data) & 0xffff) |
+					(vcpu->arch.gprs[rt] << 16);
+			break;
+		case 3:
+			*(u64 *)data = ((*(u64 *)data) & 0xffffff) |
+					(vcpu->arch.gprs[rt] << 24);
+			break;
+		case 4:
+			*(u64 *)data = ((*(u64 *)data) & 0xffffffff) |
+					(vcpu->arch.gprs[rt] << 32);
+			break;
+		case 5:
+			*(u64 *)data = ((*(u64 *)data) & 0xffffffffff) |
+					(vcpu->arch.gprs[rt] << 40);
+			break;
+		case 6:
+			*(u64 *)data = ((*(u64 *)data) & 0xffffffffffff) |
+					(vcpu->arch.gprs[rt] << 48);
+			break;
+		case 7:
+			*(u64 *)data = ((*(u64 *)data) & 0xffffffffffffff) |
+					(vcpu->arch.gprs[rt] << 56);
+			break;
+		default:
+			break;
+		}
+
+		kvm_debug("[%#lx] OP_SDR: eaddr: %#lx, gpr: %#lx, data: %llx\n",
+			  vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+			  vcpu->arch.gprs[rt], *(u64 *)data);
+		break;
+#endif
+
+#ifdef CONFIG_CPU_LOONGSON64
+	case sdc2_op:
+		rt = inst.loongson3_lsdc2_format.rt;
+		switch (inst.loongson3_lsdc2_format.opcode1) {
+		/*
+		 * Loongson-3 overridden sdc2 instructions.
+		 * opcode1              instruction
+		 *   0x0          gssbx: store 1 bytes from GPR
+		 *   0x1          gsshx: store 2 bytes from GPR
+		 *   0x2          gsswx: store 4 bytes from GPR
+		 *   0x3          gssdx: store 8 bytes from GPR
+		 */
+		case 0x0:
+			run->mmio.len = 1;
+			*(u8 *)data = vcpu->arch.gprs[rt];
+
+			kvm_debug("[%#lx] OP_GSSBX: eaddr: %#lx, gpr: %#lx, data: %#x\n",
+				  vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+				  vcpu->arch.gprs[rt], *(u8 *)data);
+			break;
+		case 0x1:
+			run->mmio.len = 2;
+			*(u16 *)data = vcpu->arch.gprs[rt];
+
+			kvm_debug("[%#lx] OP_GSSSHX: eaddr: %#lx, gpr: %#lx, data: %#x\n",
+				  vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+				  vcpu->arch.gprs[rt], *(u16 *)data);
+			break;
+		case 0x2:
+			run->mmio.len = 4;
+			*(u32 *)data = vcpu->arch.gprs[rt];
+
+			kvm_debug("[%#lx] OP_GSSWX: eaddr: %#lx, gpr: %#lx, data: %#x\n",
+				  vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+				  vcpu->arch.gprs[rt], *(u32 *)data);
+			break;
+		case 0x3:
+			run->mmio.len = 8;
+			*(u64 *)data = vcpu->arch.gprs[rt];
+
+			kvm_debug("[%#lx] OP_GSSDX: eaddr: %#lx, gpr: %#lx, data: %#llx\n",
+				  vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
+				  vcpu->arch.gprs[rt], *(u64 *)data);
+			break;
+		default:
+			kvm_err("Godson Extended GS-Store not yet supported (inst=0x%08x)\n",
+				inst.word);
+			break;
+		}
+		break;
+#endif
+	default:
+		kvm_err("Store not yet supported (inst=0x%08x)\n",
+			inst.word);
+		goto out_fail;
+	}
+
+	vcpu->mmio_needed = 1;
+	run->mmio.is_write = 1;
+	vcpu->mmio_is_write = 1;
+
+	r = kvm_io_bus_write(vcpu, KVM_MMIO_BUS,
+			run->mmio.phys_addr, run->mmio.len, data);
+
+	if (!r) {
+		vcpu->mmio_needed = 0;
+		return EMULATE_DONE;
+	}
+
+	return EMULATE_DO_MMIO;
+
+out_fail:
+	/* Rollback PC if emulation was unsuccessful */
+	vcpu->arch.pc = curr_pc;
+	return EMULATE_FAIL;
+}
+
+enum emulation_result kvm_mips_emulate_load(union mips_instruction inst,
+					    u32 cause, struct kvm_vcpu *vcpu)
+{
+	struct kvm_run *run = vcpu->run;
+	int r;
+	enum emulation_result er;
+	unsigned long curr_pc;
+	u32 op, rt;
+	unsigned int imme;
+
+	rt = inst.i_format.rt;
+	op = inst.i_format.opcode;
+
+	/*
+	 * Find the resume PC now while we have safe and easy access to the
+	 * prior branch instruction, and save it for
+	 * kvm_mips_complete_mmio_load() to restore later.
+	 */
+	curr_pc = vcpu->arch.pc;
+	er = update_pc(vcpu, cause);
+	if (er == EMULATE_FAIL)
+		return er;
+	vcpu->arch.io_pc = vcpu->arch.pc;
+	vcpu->arch.pc = curr_pc;
+
+	vcpu->arch.io_gpr = rt;
+
+	run->mmio.phys_addr = kvm_mips_callbacks->gva_to_gpa(
+						vcpu->arch.host_cp0_badvaddr);
+	if (run->mmio.phys_addr == KVM_INVALID_ADDR)
+		return EMULATE_FAIL;
+
+	vcpu->mmio_needed = 2;	/* signed */
+	switch (op) {
+#if defined(CONFIG_64BIT)
+	case ld_op:
+		run->mmio.len = 8;
+		break;
+
+	case lwu_op:
+		vcpu->mmio_needed = 1;	/* unsigned */
+		fallthrough;
+#endif
+	case lw_op:
+		run->mmio.len = 4;
+		break;
+
+	case lhu_op:
+		vcpu->mmio_needed = 1;	/* unsigned */
+		fallthrough;
+	case lh_op:
+		run->mmio.len = 2;
+		break;
+
+	case lbu_op:
+		vcpu->mmio_needed = 1;	/* unsigned */
+		fallthrough;
+	case lb_op:
+		run->mmio.len = 1;
+		break;
+
+	case lwl_op:
+		run->mmio.phys_addr = kvm_mips_callbacks->gva_to_gpa(
+					vcpu->arch.host_cp0_badvaddr) & (~0x3);
+
+		run->mmio.len = 4;
+		imme = vcpu->arch.host_cp0_badvaddr & 0x3;
+		switch (imme) {
+		case 0:
+			vcpu->mmio_needed = 3;	/* 1 byte */
+			break;
+		case 1:
+			vcpu->mmio_needed = 4;	/* 2 bytes */
+			break;
+		case 2:
+			vcpu->mmio_needed = 5;	/* 3 bytes */
+			break;
+		case 3:
+			vcpu->mmio_needed = 6;	/* 4 bytes */
+			break;
+		default:
+			break;
+		}
+		break;
+
+	case lwr_op:
+		run->mmio.phys_addr = kvm_mips_callbacks->gva_to_gpa(
+					vcpu->arch.host_cp0_badvaddr) & (~0x3);
+
+		run->mmio.len = 4;
+		imme = vcpu->arch.host_cp0_badvaddr & 0x3;
+		switch (imme) {
+		case 0:
+			vcpu->mmio_needed = 7;	/* 4 bytes */
+			break;
+		case 1:
+			vcpu->mmio_needed = 8;	/* 3 bytes */
+			break;
+		case 2:
+			vcpu->mmio_needed = 9;	/* 2 bytes */
+			break;
+		case 3:
+			vcpu->mmio_needed = 10;	/* 1 byte */
+			break;
+		default:
+			break;
+		}
+		break;
+
+#if defined(CONFIG_64BIT)
+	case ldl_op:
+		run->mmio.phys_addr = kvm_mips_callbacks->gva_to_gpa(
+					vcpu->arch.host_cp0_badvaddr) & (~0x7);
+
+		run->mmio.len = 8;
+		imme = vcpu->arch.host_cp0_badvaddr & 0x7;
+		switch (imme) {
+		case 0:
+			vcpu->mmio_needed = 11;	/* 1 byte */
+			break;
+		case 1:
+			vcpu->mmio_needed = 12;	/* 2 bytes */
+			break;
+		case 2:
+			vcpu->mmio_needed = 13;	/* 3 bytes */
+			break;
+		case 3:
+			vcpu->mmio_needed = 14;	/* 4 bytes */
+			break;
+		case 4:
+			vcpu->mmio_needed = 15;	/* 5 bytes */
+			break;
+		case 5:
+			vcpu->mmio_needed = 16;	/* 6 bytes */
+			break;
+		case 6:
+			vcpu->mmio_needed = 17;	/* 7 bytes */
+			break;
+		case 7:
+			vcpu->mmio_needed = 18;	/* 8 bytes */
+			break;
+		default:
+			break;
+		}
+		break;
+
+	case ldr_op:
+		run->mmio.phys_addr = kvm_mips_callbacks->gva_to_gpa(
+					vcpu->arch.host_cp0_badvaddr) & (~0x7);
+
+		run->mmio.len = 8;
+		imme = vcpu->arch.host_cp0_badvaddr & 0x7;
+		switch (imme) {
+		case 0:
+			vcpu->mmio_needed = 19;	/* 8 bytes */
+			break;
+		case 1:
+			vcpu->mmio_needed = 20;	/* 7 bytes */
+			break;
+		case 2:
+			vcpu->mmio_needed = 21;	/* 6 bytes */
+			break;
+		case 3:
+			vcpu->mmio_needed = 22;	/* 5 bytes */
+			break;
+		case 4:
+			vcpu->mmio_needed = 23;	/* 4 bytes */
+			break;
+		case 5:
+			vcpu->mmio_needed = 24;	/* 3 bytes */
+			break;
+		case 6:
+			vcpu->mmio_needed = 25;	/* 2 bytes */
+			break;
+		case 7:
+			vcpu->mmio_needed = 26;	/* 1 byte */
+			break;
+		default:
+			break;
+		}
+		break;
+#endif
+
+#ifdef CONFIG_CPU_LOONGSON64
+	case ldc2_op:
+		rt = inst.loongson3_lsdc2_format.rt;
+		switch (inst.loongson3_lsdc2_format.opcode1) {
+		/*
+		 * Loongson-3 overridden ldc2 instructions.
+		 * opcode1              instruction
+		 *   0x0          gslbx: store 1 bytes from GPR
+		 *   0x1          gslhx: store 2 bytes from GPR
+		 *   0x2          gslwx: store 4 bytes from GPR
+		 *   0x3          gsldx: store 8 bytes from GPR
+		 */
+		case 0x0:
+			run->mmio.len = 1;
+			vcpu->mmio_needed = 27;	/* signed */
+			break;
+		case 0x1:
+			run->mmio.len = 2;
+			vcpu->mmio_needed = 28;	/* signed */
+			break;
+		case 0x2:
+			run->mmio.len = 4;
+			vcpu->mmio_needed = 29;	/* signed */
+			break;
+		case 0x3:
+			run->mmio.len = 8;
+			vcpu->mmio_needed = 30;	/* signed */
+			break;
+		default:
+			kvm_err("Godson Extended GS-Load for float not yet supported (inst=0x%08x)\n",
+				inst.word);
+			break;
+		}
+		break;
+#endif
+
+	default:
+		kvm_err("Load not yet supported (inst=0x%08x)\n",
+			inst.word);
+		vcpu->mmio_needed = 0;
+		return EMULATE_FAIL;
+	}
+
+	run->mmio.is_write = 0;
+	vcpu->mmio_is_write = 0;
+
+	r = kvm_io_bus_read(vcpu, KVM_MMIO_BUS,
+			run->mmio.phys_addr, run->mmio.len, run->mmio.data);
+
+	if (!r) {
+		kvm_mips_complete_mmio_load(vcpu);
+		vcpu->mmio_needed = 0;
+		return EMULATE_DONE;
+	}
+
+	return EMULATE_DO_MMIO;
+}
+
+enum emulation_result kvm_mips_complete_mmio_load(struct kvm_vcpu *vcpu)
+{
+	struct kvm_run *run = vcpu->run;
+	unsigned long *gpr = &vcpu->arch.gprs[vcpu->arch.io_gpr];
+	enum emulation_result er = EMULATE_DONE;
+
+	if (run->mmio.len > sizeof(*gpr)) {
+		kvm_err("Bad MMIO length: %d", run->mmio.len);
+		er = EMULATE_FAIL;
+		goto done;
+	}
+
+	/* Restore saved resume PC */
+	vcpu->arch.pc = vcpu->arch.io_pc;
+
+	switch (run->mmio.len) {
+	case 8:
+		switch (vcpu->mmio_needed) {
+		case 11:
+			*gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffffffffffff) |
+				(((*(s64 *)run->mmio.data) & 0xff) << 56);
+			break;
+		case 12:
+			*gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffffffffff) |
+				(((*(s64 *)run->mmio.data) & 0xffff) << 48);
+			break;
+		case 13:
+			*gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffffffff) |
+				(((*(s64 *)run->mmio.data) & 0xffffff) << 40);
+			break;
+		case 14:
+			*gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffffff) |
+				(((*(s64 *)run->mmio.data) & 0xffffffff) << 32);
+			break;
+		case 15:
+			*gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffff) |
+				(((*(s64 *)run->mmio.data) & 0xffffffffff) << 24);
+			break;
+		case 16:
+			*gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffff) |
+				(((*(s64 *)run->mmio.data) & 0xffffffffffff) << 16);
+			break;
+		case 17:
+			*gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xff) |
+				(((*(s64 *)run->mmio.data) & 0xffffffffffffff) << 8);
+			break;
+		case 18:
+		case 19:
+			*gpr = *(s64 *)run->mmio.data;
+			break;
+		case 20:
+			*gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xff00000000000000) |
+				((((*(s64 *)run->mmio.data)) >> 8) & 0xffffffffffffff);
+			break;
+		case 21:
+			*gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffff000000000000) |
+				((((*(s64 *)run->mmio.data)) >> 16) & 0xffffffffffff);
+			break;
+		case 22:
+			*gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffff0000000000) |
+				((((*(s64 *)run->mmio.data)) >> 24) & 0xffffffffff);
+			break;
+		case 23:
+			*gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffffff00000000) |
+				((((*(s64 *)run->mmio.data)) >> 32) & 0xffffffff);
+			break;
+		case 24:
+			*gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffffffff000000) |
+				((((*(s64 *)run->mmio.data)) >> 40) & 0xffffff);
+			break;
+		case 25:
+			*gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffffffffff0000) |
+				((((*(s64 *)run->mmio.data)) >> 48) & 0xffff);
+			break;
+		case 26:
+			*gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffffffffffff00) |
+				((((*(s64 *)run->mmio.data)) >> 56) & 0xff);
+			break;
+		default:
+			*gpr = *(s64 *)run->mmio.data;
+		}
+		break;
+
+	case 4:
+		switch (vcpu->mmio_needed) {
+		case 1:
+			*gpr = *(u32 *)run->mmio.data;
+			break;
+		case 2:
+			*gpr = *(s32 *)run->mmio.data;
+			break;
+		case 3:
+			*gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffff) |
+				(((*(s32 *)run->mmio.data) & 0xff) << 24);
+			break;
+		case 4:
+			*gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffff) |
+				(((*(s32 *)run->mmio.data) & 0xffff) << 16);
+			break;
+		case 5:
+			*gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xff) |
+				(((*(s32 *)run->mmio.data) & 0xffffff) << 8);
+			break;
+		case 6:
+		case 7:
+			*gpr = *(s32 *)run->mmio.data;
+			break;
+		case 8:
+			*gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xff000000) |
+				((((*(s32 *)run->mmio.data)) >> 8) & 0xffffff);
+			break;
+		case 9:
+			*gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffff0000) |
+				((((*(s32 *)run->mmio.data)) >> 16) & 0xffff);
+			break;
+		case 10:
+			*gpr = (vcpu->arch.gprs[vcpu->arch.io_gpr] & 0xffffff00) |
+				((((*(s32 *)run->mmio.data)) >> 24) & 0xff);
+			break;
+		default:
+			*gpr = *(s32 *)run->mmio.data;
+		}
+		break;
+
+	case 2:
+		if (vcpu->mmio_needed == 1)
+			*gpr = *(u16 *)run->mmio.data;
+		else
+			*gpr = *(s16 *)run->mmio.data;
+
+		break;
+	case 1:
+		if (vcpu->mmio_needed == 1)
+			*gpr = *(u8 *)run->mmio.data;
+		else
+			*gpr = *(s8 *)run->mmio.data;
+		break;
+	}
+
+done:
+	return er;
+}
diff --git a/arch/mips/kvm/entry.c b/arch/mips/kvm/entry.c
new file mode 100644
index 000000000..aceed14aa
--- /dev/null
+++ b/arch/mips/kvm/entry.c
@@ -0,0 +1,916 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Generation of main entry point for the guest, exception handling.
+ *
+ * Copyright (C) 2012  MIPS Technologies, Inc.
+ * Authors: Sanjay Lal <sanjayl@kymasys.com>
+ *
+ * Copyright (C) 2016 Imagination Technologies Ltd.
+ */
+
+#include <linux/kvm_host.h>
+#include <linux/log2.h>
+#include <asm/mmu_context.h>
+#include <asm/msa.h>
+#include <asm/setup.h>
+#include <asm/tlbex.h>
+#include <asm/uasm.h>
+
+/* Register names */
+#define ZERO		0
+#define AT		1
+#define V0		2
+#define V1		3
+#define A0		4
+#define A1		5
+
+#if _MIPS_SIM == _MIPS_SIM_ABI32
+#define T0		8
+#define T1		9
+#define T2		10
+#define T3		11
+#endif /* _MIPS_SIM == _MIPS_SIM_ABI32 */
+
+#if _MIPS_SIM == _MIPS_SIM_ABI64 || _MIPS_SIM == _MIPS_SIM_NABI32
+#define T0		12
+#define T1		13
+#define T2		14
+#define T3		15
+#endif /* _MIPS_SIM == _MIPS_SIM_ABI64 || _MIPS_SIM == _MIPS_SIM_NABI32 */
+
+#define S0		16
+#define S1		17
+#define T9		25
+#define K0		26
+#define K1		27
+#define GP		28
+#define SP		29
+#define RA		31
+
+/* Some CP0 registers */
+#define C0_PWBASE	5, 5
+#define C0_HWRENA	7, 0
+#define C0_BADVADDR	8, 0
+#define C0_BADINSTR	8, 1
+#define C0_BADINSTRP	8, 2
+#define C0_PGD		9, 7
+#define C0_ENTRYHI	10, 0
+#define C0_GUESTCTL1	10, 4
+#define C0_STATUS	12, 0
+#define C0_GUESTCTL0	12, 6
+#define C0_CAUSE	13, 0
+#define C0_EPC		14, 0
+#define C0_EBASE	15, 1
+#define C0_CONFIG5	16, 5
+#define C0_DDATA_LO	28, 3
+#define C0_ERROREPC	30, 0
+
+#define CALLFRAME_SIZ   32
+
+#ifdef CONFIG_64BIT
+#define ST0_KX_IF_64	ST0_KX
+#else
+#define ST0_KX_IF_64	0
+#endif
+
+static unsigned int scratch_vcpu[2] = { C0_DDATA_LO };
+static unsigned int scratch_tmp[2] = { C0_ERROREPC };
+
+enum label_id {
+	label_fpu_1 = 1,
+	label_msa_1,
+	label_return_to_host,
+	label_kernel_asid,
+	label_exit_common,
+};
+
+UASM_L_LA(_fpu_1)
+UASM_L_LA(_msa_1)
+UASM_L_LA(_return_to_host)
+UASM_L_LA(_kernel_asid)
+UASM_L_LA(_exit_common)
+
+static void *kvm_mips_build_enter_guest(void *addr);
+static void *kvm_mips_build_ret_from_exit(void *addr);
+static void *kvm_mips_build_ret_to_guest(void *addr);
+static void *kvm_mips_build_ret_to_host(void *addr);
+
+/*
+ * The version of this function in tlbex.c uses current_cpu_type(), but for KVM
+ * we assume symmetry.
+ */
+static int c0_kscratch(void)
+{
+	return 31;
+}
+
+/**
+ * kvm_mips_entry_setup() - Perform global setup for entry code.
+ *
+ * Perform global setup for entry code, such as choosing a scratch register.
+ *
+ * Returns:	0 on success.
+ *		-errno on failure.
+ */
+int kvm_mips_entry_setup(void)
+{
+	/*
+	 * We prefer to use KScratchN registers if they are available over the
+	 * defaults above, which may not work on all cores.
+	 */
+	unsigned int kscratch_mask = cpu_data[0].kscratch_mask;
+
+	if (pgd_reg != -1)
+		kscratch_mask &= ~BIT(pgd_reg);
+
+	/* Pick a scratch register for storing VCPU */
+	if (kscratch_mask) {
+		scratch_vcpu[0] = c0_kscratch();
+		scratch_vcpu[1] = ffs(kscratch_mask) - 1;
+		kscratch_mask &= ~BIT(scratch_vcpu[1]);
+	}
+
+	/* Pick a scratch register to use as a temp for saving state */
+	if (kscratch_mask) {
+		scratch_tmp[0] = c0_kscratch();
+		scratch_tmp[1] = ffs(kscratch_mask) - 1;
+		kscratch_mask &= ~BIT(scratch_tmp[1]);
+	}
+
+	return 0;
+}
+
+static void kvm_mips_build_save_scratch(u32 **p, unsigned int tmp,
+					unsigned int frame)
+{
+	/* Save the VCPU scratch register value in cp0_epc of the stack frame */
+	UASM_i_MFC0(p, tmp, scratch_vcpu[0], scratch_vcpu[1]);
+	UASM_i_SW(p, tmp, offsetof(struct pt_regs, cp0_epc), frame);
+
+	/* Save the temp scratch register value in cp0_cause of stack frame */
+	if (scratch_tmp[0] == c0_kscratch()) {
+		UASM_i_MFC0(p, tmp, scratch_tmp[0], scratch_tmp[1]);
+		UASM_i_SW(p, tmp, offsetof(struct pt_regs, cp0_cause), frame);
+	}
+}
+
+static void kvm_mips_build_restore_scratch(u32 **p, unsigned int tmp,
+					   unsigned int frame)
+{
+	/*
+	 * Restore host scratch register values saved by
+	 * kvm_mips_build_save_scratch().
+	 */
+	UASM_i_LW(p, tmp, offsetof(struct pt_regs, cp0_epc), frame);
+	UASM_i_MTC0(p, tmp, scratch_vcpu[0], scratch_vcpu[1]);
+
+	if (scratch_tmp[0] == c0_kscratch()) {
+		UASM_i_LW(p, tmp, offsetof(struct pt_regs, cp0_cause), frame);
+		UASM_i_MTC0(p, tmp, scratch_tmp[0], scratch_tmp[1]);
+	}
+}
+
+/**
+ * build_set_exc_base() - Assemble code to write exception base address.
+ * @p:		Code buffer pointer.
+ * @reg:	Source register (generated code may set WG bit in @reg).
+ *
+ * Assemble code to modify the exception base address in the EBase register,
+ * using the appropriately sized access and setting the WG bit if necessary.
+ */
+static inline void build_set_exc_base(u32 **p, unsigned int reg)
+{
+	if (cpu_has_ebase_wg) {
+		/* Set WG so that all the bits get written */
+		uasm_i_ori(p, reg, reg, MIPS_EBASE_WG);
+		UASM_i_MTC0(p, reg, C0_EBASE);
+	} else {
+		uasm_i_mtc0(p, reg, C0_EBASE);
+	}
+}
+
+/**
+ * kvm_mips_build_vcpu_run() - Assemble function to start running a guest VCPU.
+ * @addr:	Address to start writing code.
+ *
+ * Assemble the start of the vcpu_run function to run a guest VCPU. The function
+ * conforms to the following prototype:
+ *
+ * int vcpu_run(struct kvm_vcpu *vcpu);
+ *
+ * The exit from the guest and return to the caller is handled by the code
+ * generated by kvm_mips_build_ret_to_host().
+ *
+ * Returns:	Next address after end of written function.
+ */
+void *kvm_mips_build_vcpu_run(void *addr)
+{
+	u32 *p = addr;
+	unsigned int i;
+
+	/*
+	 * A0: vcpu
+	 */
+
+	/* k0/k1 not being used in host kernel context */
+	UASM_i_ADDIU(&p, K1, SP, -(int)sizeof(struct pt_regs));
+	for (i = 16; i < 32; ++i) {
+		if (i == 24)
+			i = 28;
+		UASM_i_SW(&p, i, offsetof(struct pt_regs, regs[i]), K1);
+	}
+
+	/* Save host status */
+	uasm_i_mfc0(&p, V0, C0_STATUS);
+	UASM_i_SW(&p, V0, offsetof(struct pt_regs, cp0_status), K1);
+
+	/* Save scratch registers, will be used to store pointer to vcpu etc */
+	kvm_mips_build_save_scratch(&p, V1, K1);
+
+	/* VCPU scratch register has pointer to vcpu */
+	UASM_i_MTC0(&p, A0, scratch_vcpu[0], scratch_vcpu[1]);
+
+	/* Offset into vcpu->arch */
+	UASM_i_ADDIU(&p, K1, A0, offsetof(struct kvm_vcpu, arch));
+
+	/*
+	 * Save the host stack to VCPU, used for exception processing
+	 * when we exit from the Guest
+	 */
+	UASM_i_SW(&p, SP, offsetof(struct kvm_vcpu_arch, host_stack), K1);
+
+	/* Save the kernel gp as well */
+	UASM_i_SW(&p, GP, offsetof(struct kvm_vcpu_arch, host_gp), K1);
+
+	/*
+	 * Setup status register for running the guest in UM, interrupts
+	 * are disabled
+	 */
+	UASM_i_LA(&p, K0, ST0_EXL | KSU_USER | ST0_BEV | ST0_KX_IF_64);
+	uasm_i_mtc0(&p, K0, C0_STATUS);
+	uasm_i_ehb(&p);
+
+	/* load up the new EBASE */
+	UASM_i_LW(&p, K0, offsetof(struct kvm_vcpu_arch, guest_ebase), K1);
+	build_set_exc_base(&p, K0);
+
+	/*
+	 * Now that the new EBASE has been loaded, unset BEV, set
+	 * interrupt mask as it was but make sure that timer interrupts
+	 * are enabled
+	 */
+	uasm_i_addiu(&p, K0, ZERO, ST0_EXL | KSU_USER | ST0_IE | ST0_KX_IF_64);
+	uasm_i_andi(&p, V0, V0, ST0_IM);
+	uasm_i_or(&p, K0, K0, V0);
+	uasm_i_mtc0(&p, K0, C0_STATUS);
+	uasm_i_ehb(&p);
+
+	p = kvm_mips_build_enter_guest(p);
+
+	return p;
+}
+
+/**
+ * kvm_mips_build_enter_guest() - Assemble code to resume guest execution.
+ * @addr:	Address to start writing code.
+ *
+ * Assemble the code to resume guest execution. This code is common between the
+ * initial entry into the guest from the host, and returning from the exit
+ * handler back to the guest.
+ *
+ * Returns:	Next address after end of written function.
+ */
+static void *kvm_mips_build_enter_guest(void *addr)
+{
+	u32 *p = addr;
+	unsigned int i;
+	struct uasm_label labels[2];
+	struct uasm_reloc relocs[2];
+	struct uasm_label __maybe_unused *l = labels;
+	struct uasm_reloc __maybe_unused *r = relocs;
+
+	memset(labels, 0, sizeof(labels));
+	memset(relocs, 0, sizeof(relocs));
+
+	/* Set Guest EPC */
+	UASM_i_LW(&p, T0, offsetof(struct kvm_vcpu_arch, pc), K1);
+	UASM_i_MTC0(&p, T0, C0_EPC);
+
+	/* Save normal linux process pgd (VZ guarantees pgd_reg is set) */
+	if (cpu_has_ldpte)
+		UASM_i_MFC0(&p, K0, C0_PWBASE);
+	else
+		UASM_i_MFC0(&p, K0, c0_kscratch(), pgd_reg);
+	UASM_i_SW(&p, K0, offsetof(struct kvm_vcpu_arch, host_pgd), K1);
+
+	/*
+	 * Set up KVM GPA pgd.
+	 * This does roughly the same as TLBMISS_HANDLER_SETUP_PGD():
+	 * - call tlbmiss_handler_setup_pgd(mm->pgd)
+	 * - write mm->pgd into CP0_PWBase
+	 *
+	 * We keep S0 pointing at struct kvm so we can load the ASID below.
+	 */
+	UASM_i_LW(&p, S0, (int)offsetof(struct kvm_vcpu, kvm) -
+			  (int)offsetof(struct kvm_vcpu, arch), K1);
+	UASM_i_LW(&p, A0, offsetof(struct kvm, arch.gpa_mm.pgd), S0);
+	UASM_i_LA(&p, T9, (unsigned long)tlbmiss_handler_setup_pgd);
+	uasm_i_jalr(&p, RA, T9);
+	/* delay slot */
+	if (cpu_has_htw)
+		UASM_i_MTC0(&p, A0, C0_PWBASE);
+	else
+		uasm_i_nop(&p);
+
+	/* Set GM bit to setup eret to VZ guest context */
+	uasm_i_addiu(&p, V1, ZERO, 1);
+	uasm_i_mfc0(&p, K0, C0_GUESTCTL0);
+	uasm_i_ins(&p, K0, V1, MIPS_GCTL0_GM_SHIFT, 1);
+	uasm_i_mtc0(&p, K0, C0_GUESTCTL0);
+
+	if (cpu_has_guestid) {
+		/*
+		 * Set root mode GuestID, so that root TLB refill handler can
+		 * use the correct GuestID in the root TLB.
+		 */
+
+		/* Get current GuestID */
+		uasm_i_mfc0(&p, T0, C0_GUESTCTL1);
+		/* Set GuestCtl1.RID = GuestCtl1.ID */
+		uasm_i_ext(&p, T1, T0, MIPS_GCTL1_ID_SHIFT,
+			   MIPS_GCTL1_ID_WIDTH);
+		uasm_i_ins(&p, T0, T1, MIPS_GCTL1_RID_SHIFT,
+			   MIPS_GCTL1_RID_WIDTH);
+		uasm_i_mtc0(&p, T0, C0_GUESTCTL1);
+
+		/* GuestID handles dealiasing so we don't need to touch ASID */
+		goto skip_asid_restore;
+	}
+
+	/* Root ASID Dealias (RAD) */
+
+	/* Save host ASID */
+	UASM_i_MFC0(&p, K0, C0_ENTRYHI);
+	UASM_i_SW(&p, K0, offsetof(struct kvm_vcpu_arch, host_entryhi),
+		  K1);
+
+	/* Set the root ASID for the Guest */
+	UASM_i_ADDIU(&p, T1, S0,
+		     offsetof(struct kvm, arch.gpa_mm.context.asid));
+
+	/* t1: contains the base of the ASID array, need to get the cpu id  */
+	/* smp_processor_id */
+	uasm_i_lw(&p, T2, offsetof(struct thread_info, cpu), GP);
+	/* index the ASID array */
+	uasm_i_sll(&p, T2, T2, ilog2(sizeof(long)));
+	UASM_i_ADDU(&p, T3, T1, T2);
+	UASM_i_LW(&p, K0, 0, T3);
+#ifdef CONFIG_MIPS_ASID_BITS_VARIABLE
+	/*
+	 * reuse ASID array offset
+	 * cpuinfo_mips is a multiple of sizeof(long)
+	 */
+	uasm_i_addiu(&p, T3, ZERO, sizeof(struct cpuinfo_mips)/sizeof(long));
+	uasm_i_mul(&p, T2, T2, T3);
+
+	UASM_i_LA_mostly(&p, AT, (long)&cpu_data[0].asid_mask);
+	UASM_i_ADDU(&p, AT, AT, T2);
+	UASM_i_LW(&p, T2, uasm_rel_lo((long)&cpu_data[0].asid_mask), AT);
+	uasm_i_and(&p, K0, K0, T2);
+#else
+	uasm_i_andi(&p, K0, K0, MIPS_ENTRYHI_ASID);
+#endif
+
+	/* Set up KVM VZ root ASID (!guestid) */
+	uasm_i_mtc0(&p, K0, C0_ENTRYHI);
+skip_asid_restore:
+	uasm_i_ehb(&p);
+
+	/* Disable RDHWR access */
+	uasm_i_mtc0(&p, ZERO, C0_HWRENA);
+
+	/* load the guest context from VCPU and return */
+	for (i = 1; i < 32; ++i) {
+		/* Guest k0/k1 loaded later */
+		if (i == K0 || i == K1)
+			continue;
+		UASM_i_LW(&p, i, offsetof(struct kvm_vcpu_arch, gprs[i]), K1);
+	}
+
+#ifndef CONFIG_CPU_MIPSR6
+	/* Restore hi/lo */
+	UASM_i_LW(&p, K0, offsetof(struct kvm_vcpu_arch, hi), K1);
+	uasm_i_mthi(&p, K0);
+
+	UASM_i_LW(&p, K0, offsetof(struct kvm_vcpu_arch, lo), K1);
+	uasm_i_mtlo(&p, K0);
+#endif
+
+	/* Restore the guest's k0/k1 registers */
+	UASM_i_LW(&p, K0, offsetof(struct kvm_vcpu_arch, gprs[K0]), K1);
+	UASM_i_LW(&p, K1, offsetof(struct kvm_vcpu_arch, gprs[K1]), K1);
+
+	/* Jump to guest */
+	uasm_i_eret(&p);
+
+	uasm_resolve_relocs(relocs, labels);
+
+	return p;
+}
+
+/**
+ * kvm_mips_build_tlb_refill_exception() - Assemble TLB refill handler.
+ * @addr:	Address to start writing code.
+ * @handler:	Address of common handler (within range of @addr).
+ *
+ * Assemble TLB refill exception fast path handler for guest execution.
+ *
+ * Returns:	Next address after end of written function.
+ */
+void *kvm_mips_build_tlb_refill_exception(void *addr, void *handler)
+{
+	u32 *p = addr;
+	struct uasm_label labels[2];
+	struct uasm_reloc relocs[2];
+#ifndef CONFIG_CPU_LOONGSON64
+	struct uasm_label *l = labels;
+	struct uasm_reloc *r = relocs;
+#endif
+
+	memset(labels, 0, sizeof(labels));
+	memset(relocs, 0, sizeof(relocs));
+
+	/* Save guest k1 into scratch register */
+	UASM_i_MTC0(&p, K1, scratch_tmp[0], scratch_tmp[1]);
+
+	/* Get the VCPU pointer from the VCPU scratch register */
+	UASM_i_MFC0(&p, K1, scratch_vcpu[0], scratch_vcpu[1]);
+
+	/* Save guest k0 into VCPU structure */
+	UASM_i_SW(&p, K0, offsetof(struct kvm_vcpu, arch.gprs[K0]), K1);
+
+	/*
+	 * Some of the common tlbex code uses current_cpu_type(). For KVM we
+	 * assume symmetry and just disable preemption to silence the warning.
+	 */
+	preempt_disable();
+
+#ifdef CONFIG_CPU_LOONGSON64
+	UASM_i_MFC0(&p, K1, C0_PGD);
+	uasm_i_lddir(&p, K0, K1, 3);  /* global page dir */
+#ifndef __PAGETABLE_PMD_FOLDED
+	uasm_i_lddir(&p, K1, K0, 1);  /* middle page dir */
+#endif
+	uasm_i_ldpte(&p, K1, 0);      /* even */
+	uasm_i_ldpte(&p, K1, 1);      /* odd */
+	uasm_i_tlbwr(&p);
+#else
+	/*
+	 * Now for the actual refill bit. A lot of this can be common with the
+	 * Linux TLB refill handler, however we don't need to handle so many
+	 * cases. We only need to handle user mode refills, and user mode runs
+	 * with 32-bit addressing.
+	 *
+	 * Therefore the branch to label_vmalloc generated by build_get_pmde64()
+	 * that isn't resolved should never actually get taken and is harmless
+	 * to leave in place for now.
+	 */
+
+#ifdef CONFIG_64BIT
+	build_get_pmde64(&p, &l, &r, K0, K1); /* get pmd in K1 */
+#else
+	build_get_pgde32(&p, K0, K1); /* get pgd in K1 */
+#endif
+
+	/* we don't support huge pages yet */
+
+	build_get_ptep(&p, K0, K1);
+	build_update_entries(&p, K0, K1);
+	build_tlb_write_entry(&p, &l, &r, tlb_random);
+#endif
+
+	preempt_enable();
+
+	/* Get the VCPU pointer from the VCPU scratch register again */
+	UASM_i_MFC0(&p, K1, scratch_vcpu[0], scratch_vcpu[1]);
+
+	/* Restore the guest's k0/k1 registers */
+	UASM_i_LW(&p, K0, offsetof(struct kvm_vcpu, arch.gprs[K0]), K1);
+	uasm_i_ehb(&p);
+	UASM_i_MFC0(&p, K1, scratch_tmp[0], scratch_tmp[1]);
+
+	/* Jump to guest */
+	uasm_i_eret(&p);
+
+	return p;
+}
+
+/**
+ * kvm_mips_build_exception() - Assemble first level guest exception handler.
+ * @addr:	Address to start writing code.
+ * @handler:	Address of common handler (within range of @addr).
+ *
+ * Assemble exception vector code for guest execution. The generated vector will
+ * branch to the common exception handler generated by kvm_mips_build_exit().
+ *
+ * Returns:	Next address after end of written function.
+ */
+void *kvm_mips_build_exception(void *addr, void *handler)
+{
+	u32 *p = addr;
+	struct uasm_label labels[2];
+	struct uasm_reloc relocs[2];
+	struct uasm_label *l = labels;
+	struct uasm_reloc *r = relocs;
+
+	memset(labels, 0, sizeof(labels));
+	memset(relocs, 0, sizeof(relocs));
+
+	/* Save guest k1 into scratch register */
+	UASM_i_MTC0(&p, K1, scratch_tmp[0], scratch_tmp[1]);
+
+	/* Get the VCPU pointer from the VCPU scratch register */
+	UASM_i_MFC0(&p, K1, scratch_vcpu[0], scratch_vcpu[1]);
+	UASM_i_ADDIU(&p, K1, K1, offsetof(struct kvm_vcpu, arch));
+
+	/* Save guest k0 into VCPU structure */
+	UASM_i_SW(&p, K0, offsetof(struct kvm_vcpu_arch, gprs[K0]), K1);
+
+	/* Branch to the common handler */
+	uasm_il_b(&p, &r, label_exit_common);
+	 uasm_i_nop(&p);
+
+	uasm_l_exit_common(&l, handler);
+	uasm_resolve_relocs(relocs, labels);
+
+	return p;
+}
+
+/**
+ * kvm_mips_build_exit() - Assemble common guest exit handler.
+ * @addr:	Address to start writing code.
+ *
+ * Assemble the generic guest exit handling code. This is called by the
+ * exception vectors (generated by kvm_mips_build_exception()), and calls
+ * kvm_mips_handle_exit(), then either resumes the guest or returns to the host
+ * depending on the return value.
+ *
+ * Returns:	Next address after end of written function.
+ */
+void *kvm_mips_build_exit(void *addr)
+{
+	u32 *p = addr;
+	unsigned int i;
+	struct uasm_label labels[3];
+	struct uasm_reloc relocs[3];
+	struct uasm_label *l = labels;
+	struct uasm_reloc *r = relocs;
+
+	memset(labels, 0, sizeof(labels));
+	memset(relocs, 0, sizeof(relocs));
+
+	/*
+	 * Generic Guest exception handler. We end up here when the guest
+	 * does something that causes a trap to kernel mode.
+	 *
+	 * Both k0/k1 registers will have already been saved (k0 into the vcpu
+	 * structure, and k1 into the scratch_tmp register).
+	 *
+	 * The k1 register will already contain the kvm_vcpu_arch pointer.
+	 */
+
+	/* Start saving Guest context to VCPU */
+	for (i = 0; i < 32; ++i) {
+		/* Guest k0/k1 saved later */
+		if (i == K0 || i == K1)
+			continue;
+		UASM_i_SW(&p, i, offsetof(struct kvm_vcpu_arch, gprs[i]), K1);
+	}
+
+#ifndef CONFIG_CPU_MIPSR6
+	/* We need to save hi/lo and restore them on the way out */
+	uasm_i_mfhi(&p, T0);
+	UASM_i_SW(&p, T0, offsetof(struct kvm_vcpu_arch, hi), K1);
+
+	uasm_i_mflo(&p, T0);
+	UASM_i_SW(&p, T0, offsetof(struct kvm_vcpu_arch, lo), K1);
+#endif
+
+	/* Finally save guest k1 to VCPU */
+	uasm_i_ehb(&p);
+	UASM_i_MFC0(&p, T0, scratch_tmp[0], scratch_tmp[1]);
+	UASM_i_SW(&p, T0, offsetof(struct kvm_vcpu_arch, gprs[K1]), K1);
+
+	/* Now that context has been saved, we can use other registers */
+
+	/* Restore vcpu */
+	UASM_i_MFC0(&p, S0, scratch_vcpu[0], scratch_vcpu[1]);
+
+	/*
+	 * Save Host level EPC, BadVaddr and Cause to VCPU, useful to process
+	 * the exception
+	 */
+	UASM_i_MFC0(&p, K0, C0_EPC);
+	UASM_i_SW(&p, K0, offsetof(struct kvm_vcpu_arch, pc), K1);
+
+	UASM_i_MFC0(&p, K0, C0_BADVADDR);
+	UASM_i_SW(&p, K0, offsetof(struct kvm_vcpu_arch, host_cp0_badvaddr),
+		  K1);
+
+	uasm_i_mfc0(&p, K0, C0_CAUSE);
+	uasm_i_sw(&p, K0, offsetof(struct kvm_vcpu_arch, host_cp0_cause), K1);
+
+	if (cpu_has_badinstr) {
+		uasm_i_mfc0(&p, K0, C0_BADINSTR);
+		uasm_i_sw(&p, K0, offsetof(struct kvm_vcpu_arch,
+					   host_cp0_badinstr), K1);
+	}
+
+	if (cpu_has_badinstrp) {
+		uasm_i_mfc0(&p, K0, C0_BADINSTRP);
+		uasm_i_sw(&p, K0, offsetof(struct kvm_vcpu_arch,
+					   host_cp0_badinstrp), K1);
+	}
+
+	/* Now restore the host state just enough to run the handlers */
+
+	/* Switch EBASE to the one used by Linux */
+	/* load up the host EBASE */
+	uasm_i_mfc0(&p, V0, C0_STATUS);
+
+	uasm_i_lui(&p, AT, ST0_BEV >> 16);
+	uasm_i_or(&p, K0, V0, AT);
+
+	uasm_i_mtc0(&p, K0, C0_STATUS);
+	uasm_i_ehb(&p);
+
+	UASM_i_LA_mostly(&p, K0, (long)&ebase);
+	UASM_i_LW(&p, K0, uasm_rel_lo((long)&ebase), K0);
+	build_set_exc_base(&p, K0);
+
+	if (raw_cpu_has_fpu) {
+		/*
+		 * If FPU is enabled, save FCR31 and clear it so that later
+		 * ctc1's don't trigger FPE for pending exceptions.
+		 */
+		uasm_i_lui(&p, AT, ST0_CU1 >> 16);
+		uasm_i_and(&p, V1, V0, AT);
+		uasm_il_beqz(&p, &r, V1, label_fpu_1);
+		 uasm_i_nop(&p);
+		uasm_i_cfc1(&p, T0, 31);
+		uasm_i_sw(&p, T0, offsetof(struct kvm_vcpu_arch, fpu.fcr31),
+			  K1);
+		uasm_i_ctc1(&p, ZERO, 31);
+		uasm_l_fpu_1(&l, p);
+	}
+
+	if (cpu_has_msa) {
+		/*
+		 * If MSA is enabled, save MSACSR and clear it so that later
+		 * instructions don't trigger MSAFPE for pending exceptions.
+		 */
+		uasm_i_mfc0(&p, T0, C0_CONFIG5);
+		uasm_i_ext(&p, T0, T0, 27, 1); /* MIPS_CONF5_MSAEN */
+		uasm_il_beqz(&p, &r, T0, label_msa_1);
+		 uasm_i_nop(&p);
+		uasm_i_cfcmsa(&p, T0, MSA_CSR);
+		uasm_i_sw(&p, T0, offsetof(struct kvm_vcpu_arch, fpu.msacsr),
+			  K1);
+		uasm_i_ctcmsa(&p, MSA_CSR, ZERO);
+		uasm_l_msa_1(&l, p);
+	}
+
+	/* Restore host ASID */
+	if (!cpu_has_guestid) {
+		UASM_i_LW(&p, K0, offsetof(struct kvm_vcpu_arch, host_entryhi),
+			  K1);
+		UASM_i_MTC0(&p, K0, C0_ENTRYHI);
+	}
+
+	/*
+	 * Set up normal Linux process pgd.
+	 * This does roughly the same as TLBMISS_HANDLER_SETUP_PGD():
+	 * - call tlbmiss_handler_setup_pgd(mm->pgd)
+	 * - write mm->pgd into CP0_PWBase
+	 */
+	UASM_i_LW(&p, A0,
+		  offsetof(struct kvm_vcpu_arch, host_pgd), K1);
+	UASM_i_LA(&p, T9, (unsigned long)tlbmiss_handler_setup_pgd);
+	uasm_i_jalr(&p, RA, T9);
+	/* delay slot */
+	if (cpu_has_htw)
+		UASM_i_MTC0(&p, A0, C0_PWBASE);
+	else
+		uasm_i_nop(&p);
+
+	/* Clear GM bit so we don't enter guest mode when EXL is cleared */
+	uasm_i_mfc0(&p, K0, C0_GUESTCTL0);
+	uasm_i_ins(&p, K0, ZERO, MIPS_GCTL0_GM_SHIFT, 1);
+	uasm_i_mtc0(&p, K0, C0_GUESTCTL0);
+
+	/* Save GuestCtl0 so we can access GExcCode after CPU migration */
+	uasm_i_sw(&p, K0,
+		  offsetof(struct kvm_vcpu_arch, host_cp0_guestctl0), K1);
+
+	if (cpu_has_guestid) {
+		/*
+		 * Clear root mode GuestID, so that root TLB operations use the
+		 * root GuestID in the root TLB.
+		 */
+		uasm_i_mfc0(&p, T0, C0_GUESTCTL1);
+		/* Set GuestCtl1.RID = MIPS_GCTL1_ROOT_GUESTID (i.e. 0) */
+		uasm_i_ins(&p, T0, ZERO, MIPS_GCTL1_RID_SHIFT,
+			   MIPS_GCTL1_RID_WIDTH);
+		uasm_i_mtc0(&p, T0, C0_GUESTCTL1);
+	}
+
+	/* Now that the new EBASE has been loaded, unset BEV and KSU_USER */
+	uasm_i_addiu(&p, AT, ZERO, ~(ST0_EXL | KSU_USER | ST0_IE));
+	uasm_i_and(&p, V0, V0, AT);
+	uasm_i_lui(&p, AT, ST0_CU0 >> 16);
+	uasm_i_or(&p, V0, V0, AT);
+#ifdef CONFIG_64BIT
+	uasm_i_ori(&p, V0, V0, ST0_SX | ST0_UX);
+#endif
+	uasm_i_mtc0(&p, V0, C0_STATUS);
+	uasm_i_ehb(&p);
+
+	/* Load up host GP */
+	UASM_i_LW(&p, GP, offsetof(struct kvm_vcpu_arch, host_gp), K1);
+
+	/* Need a stack before we can jump to "C" */
+	UASM_i_LW(&p, SP, offsetof(struct kvm_vcpu_arch, host_stack), K1);
+
+	/* Saved host state */
+	UASM_i_ADDIU(&p, SP, SP, -(int)sizeof(struct pt_regs));
+
+	/*
+	 * XXXKYMA do we need to load the host ASID, maybe not because the
+	 * kernel entries are marked GLOBAL, need to verify
+	 */
+
+	/* Restore host scratch registers, as we'll have clobbered them */
+	kvm_mips_build_restore_scratch(&p, K0, SP);
+
+	/* Restore RDHWR access */
+	UASM_i_LA_mostly(&p, K0, (long)&hwrena);
+	uasm_i_lw(&p, K0, uasm_rel_lo((long)&hwrena), K0);
+	uasm_i_mtc0(&p, K0, C0_HWRENA);
+
+	/* Jump to handler */
+	/*
+	 * XXXKYMA: not sure if this is safe, how large is the stack??
+	 * Now jump to the kvm_mips_handle_exit() to see if we can deal
+	 * with this in the kernel
+	 */
+	uasm_i_move(&p, A0, S0);
+	UASM_i_LA(&p, T9, (unsigned long)kvm_mips_handle_exit);
+	uasm_i_jalr(&p, RA, T9);
+	 UASM_i_ADDIU(&p, SP, SP, -CALLFRAME_SIZ);
+
+	uasm_resolve_relocs(relocs, labels);
+
+	p = kvm_mips_build_ret_from_exit(p);
+
+	return p;
+}
+
+/**
+ * kvm_mips_build_ret_from_exit() - Assemble guest exit return handler.
+ * @addr:	Address to start writing code.
+ *
+ * Assemble the code to handle the return from kvm_mips_handle_exit(), either
+ * resuming the guest or returning to the host depending on the return value.
+ *
+ * Returns:	Next address after end of written function.
+ */
+static void *kvm_mips_build_ret_from_exit(void *addr)
+{
+	u32 *p = addr;
+	struct uasm_label labels[2];
+	struct uasm_reloc relocs[2];
+	struct uasm_label *l = labels;
+	struct uasm_reloc *r = relocs;
+
+	memset(labels, 0, sizeof(labels));
+	memset(relocs, 0, sizeof(relocs));
+
+	/* Return from handler Make sure interrupts are disabled */
+	uasm_i_di(&p, ZERO);
+	uasm_i_ehb(&p);
+
+	/*
+	 * XXXKYMA: k0/k1 could have been blown away if we processed
+	 * an exception while we were handling the exception from the
+	 * guest, reload k1
+	 */
+
+	uasm_i_move(&p, K1, S0);
+	UASM_i_ADDIU(&p, K1, K1, offsetof(struct kvm_vcpu, arch));
+
+	/*
+	 * Check return value, should tell us if we are returning to the
+	 * host (handle I/O etc)or resuming the guest
+	 */
+	uasm_i_andi(&p, T0, V0, RESUME_HOST);
+	uasm_il_bnez(&p, &r, T0, label_return_to_host);
+	 uasm_i_nop(&p);
+
+	p = kvm_mips_build_ret_to_guest(p);
+
+	uasm_l_return_to_host(&l, p);
+	p = kvm_mips_build_ret_to_host(p);
+
+	uasm_resolve_relocs(relocs, labels);
+
+	return p;
+}
+
+/**
+ * kvm_mips_build_ret_to_guest() - Assemble code to return to the guest.
+ * @addr:	Address to start writing code.
+ *
+ * Assemble the code to handle return from the guest exit handler
+ * (kvm_mips_handle_exit()) back to the guest.
+ *
+ * Returns:	Next address after end of written function.
+ */
+static void *kvm_mips_build_ret_to_guest(void *addr)
+{
+	u32 *p = addr;
+
+	/* Put the saved pointer to vcpu (s0) back into the scratch register */
+	UASM_i_MTC0(&p, S0, scratch_vcpu[0], scratch_vcpu[1]);
+
+	/* Load up the Guest EBASE to minimize the window where BEV is set */
+	UASM_i_LW(&p, T0, offsetof(struct kvm_vcpu_arch, guest_ebase), K1);
+
+	/* Switch EBASE back to the one used by KVM */
+	uasm_i_mfc0(&p, V1, C0_STATUS);
+	uasm_i_lui(&p, AT, ST0_BEV >> 16);
+	uasm_i_or(&p, K0, V1, AT);
+	uasm_i_mtc0(&p, K0, C0_STATUS);
+	uasm_i_ehb(&p);
+	build_set_exc_base(&p, T0);
+
+	/* Setup status register for running guest in UM */
+	uasm_i_ori(&p, V1, V1, ST0_EXL | KSU_USER | ST0_IE);
+	UASM_i_LA(&p, AT, ~(ST0_CU0 | ST0_MX | ST0_SX | ST0_UX));
+	uasm_i_and(&p, V1, V1, AT);
+	uasm_i_mtc0(&p, V1, C0_STATUS);
+	uasm_i_ehb(&p);
+
+	p = kvm_mips_build_enter_guest(p);
+
+	return p;
+}
+
+/**
+ * kvm_mips_build_ret_to_host() - Assemble code to return to the host.
+ * @addr:	Address to start writing code.
+ *
+ * Assemble the code to handle return from the guest exit handler
+ * (kvm_mips_handle_exit()) back to the host, i.e. to the caller of the vcpu_run
+ * function generated by kvm_mips_build_vcpu_run().
+ *
+ * Returns:	Next address after end of written function.
+ */
+static void *kvm_mips_build_ret_to_host(void *addr)
+{
+	u32 *p = addr;
+	unsigned int i;
+
+	/* EBASE is already pointing to Linux */
+	UASM_i_LW(&p, K1, offsetof(struct kvm_vcpu_arch, host_stack), K1);
+	UASM_i_ADDIU(&p, K1, K1, -(int)sizeof(struct pt_regs));
+
+	/*
+	 * r2/v0 is the return code, shift it down by 2 (arithmetic)
+	 * to recover the err code
+	 */
+	uasm_i_sra(&p, K0, V0, 2);
+	uasm_i_move(&p, V0, K0);
+
+	/* Load context saved on the host stack */
+	for (i = 16; i < 31; ++i) {
+		if (i == 24)
+			i = 28;
+		UASM_i_LW(&p, i, offsetof(struct pt_regs, regs[i]), K1);
+	}
+
+	/* Restore RDHWR access */
+	UASM_i_LA_mostly(&p, K0, (long)&hwrena);
+	uasm_i_lw(&p, K0, uasm_rel_lo((long)&hwrena), K0);
+	uasm_i_mtc0(&p, K0, C0_HWRENA);
+
+	/* Restore RA, which is the address we will return to */
+	UASM_i_LW(&p, RA, offsetof(struct pt_regs, regs[RA]), K1);
+	uasm_i_jr(&p, RA);
+	 uasm_i_nop(&p);
+
+	return p;
+}
+
diff --git a/arch/mips/kvm/fpu.S b/arch/mips/kvm/fpu.S
new file mode 100644
index 000000000..eb2e8cc35
--- /dev/null
+++ b/arch/mips/kvm/fpu.S
@@ -0,0 +1,125 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * FPU context handling code for KVM.
+ *
+ * Copyright (C) 2015 Imagination Technologies Ltd.
+ */
+
+#include <asm/asm.h>
+#include <asm/asm-offsets.h>
+#include <asm/fpregdef.h>
+#include <asm/mipsregs.h>
+#include <asm/regdef.h>
+
+/* preprocessor replaces the fp in ".set fp=64" with $30 otherwise */
+#undef fp
+
+	.set	noreorder
+	.set	noat
+
+LEAF(__kvm_save_fpu)
+	.set	push
+	.set	hardfloat
+	.set	fp=64
+	mfc0	t0, CP0_STATUS
+	sll     t0, t0, 5			# is Status.FR set?
+	bgez    t0, 1f				# no: skip odd doubles
+	 nop
+	sdc1	$f1,  VCPU_FPR1(a0)
+	sdc1	$f3,  VCPU_FPR3(a0)
+	sdc1	$f5,  VCPU_FPR5(a0)
+	sdc1	$f7,  VCPU_FPR7(a0)
+	sdc1	$f9,  VCPU_FPR9(a0)
+	sdc1	$f11, VCPU_FPR11(a0)
+	sdc1	$f13, VCPU_FPR13(a0)
+	sdc1	$f15, VCPU_FPR15(a0)
+	sdc1	$f17, VCPU_FPR17(a0)
+	sdc1	$f19, VCPU_FPR19(a0)
+	sdc1	$f21, VCPU_FPR21(a0)
+	sdc1	$f23, VCPU_FPR23(a0)
+	sdc1	$f25, VCPU_FPR25(a0)
+	sdc1	$f27, VCPU_FPR27(a0)
+	sdc1	$f29, VCPU_FPR29(a0)
+	sdc1	$f31, VCPU_FPR31(a0)
+1:	sdc1	$f0,  VCPU_FPR0(a0)
+	sdc1	$f2,  VCPU_FPR2(a0)
+	sdc1	$f4,  VCPU_FPR4(a0)
+	sdc1	$f6,  VCPU_FPR6(a0)
+	sdc1	$f8,  VCPU_FPR8(a0)
+	sdc1	$f10, VCPU_FPR10(a0)
+	sdc1	$f12, VCPU_FPR12(a0)
+	sdc1	$f14, VCPU_FPR14(a0)
+	sdc1	$f16, VCPU_FPR16(a0)
+	sdc1	$f18, VCPU_FPR18(a0)
+	sdc1	$f20, VCPU_FPR20(a0)
+	sdc1	$f22, VCPU_FPR22(a0)
+	sdc1	$f24, VCPU_FPR24(a0)
+	sdc1	$f26, VCPU_FPR26(a0)
+	sdc1	$f28, VCPU_FPR28(a0)
+	jr	ra
+	 sdc1	$f30, VCPU_FPR30(a0)
+	.set	pop
+	END(__kvm_save_fpu)
+
+LEAF(__kvm_restore_fpu)
+	.set	push
+	.set	hardfloat
+	.set	fp=64
+	mfc0	t0, CP0_STATUS
+	sll     t0, t0, 5			# is Status.FR set?
+	bgez    t0, 1f				# no: skip odd doubles
+	 nop
+	ldc1	$f1,  VCPU_FPR1(a0)
+	ldc1	$f3,  VCPU_FPR3(a0)
+	ldc1	$f5,  VCPU_FPR5(a0)
+	ldc1	$f7,  VCPU_FPR7(a0)
+	ldc1	$f9,  VCPU_FPR9(a0)
+	ldc1	$f11, VCPU_FPR11(a0)
+	ldc1	$f13, VCPU_FPR13(a0)
+	ldc1	$f15, VCPU_FPR15(a0)
+	ldc1	$f17, VCPU_FPR17(a0)
+	ldc1	$f19, VCPU_FPR19(a0)
+	ldc1	$f21, VCPU_FPR21(a0)
+	ldc1	$f23, VCPU_FPR23(a0)
+	ldc1	$f25, VCPU_FPR25(a0)
+	ldc1	$f27, VCPU_FPR27(a0)
+	ldc1	$f29, VCPU_FPR29(a0)
+	ldc1	$f31, VCPU_FPR31(a0)
+1:	ldc1	$f0,  VCPU_FPR0(a0)
+	ldc1	$f2,  VCPU_FPR2(a0)
+	ldc1	$f4,  VCPU_FPR4(a0)
+	ldc1	$f6,  VCPU_FPR6(a0)
+	ldc1	$f8,  VCPU_FPR8(a0)
+	ldc1	$f10, VCPU_FPR10(a0)
+	ldc1	$f12, VCPU_FPR12(a0)
+	ldc1	$f14, VCPU_FPR14(a0)
+	ldc1	$f16, VCPU_FPR16(a0)
+	ldc1	$f18, VCPU_FPR18(a0)
+	ldc1	$f20, VCPU_FPR20(a0)
+	ldc1	$f22, VCPU_FPR22(a0)
+	ldc1	$f24, VCPU_FPR24(a0)
+	ldc1	$f26, VCPU_FPR26(a0)
+	ldc1	$f28, VCPU_FPR28(a0)
+	jr	ra
+	 ldc1	$f30, VCPU_FPR30(a0)
+	.set	pop
+	END(__kvm_restore_fpu)
+
+LEAF(__kvm_restore_fcsr)
+	.set	push
+	.set	hardfloat
+	lw	t0, VCPU_FCR31(a0)
+	/*
+	 * The ctc1 must stay at this offset in __kvm_restore_fcsr.
+	 * See kvm_mips_csr_die_notify() which handles t0 containing a value
+	 * which triggers an FP Exception, which must be stepped over and
+	 * ignored since the set cause bits must remain there for the guest.
+	 */
+	ctc1	t0, fcr31
+	jr	ra
+	 nop
+	.set	pop
+	END(__kvm_restore_fcsr)
diff --git a/arch/mips/kvm/hypcall.c b/arch/mips/kvm/hypcall.c
new file mode 100644
index 000000000..830634351
--- /dev/null
+++ b/arch/mips/kvm/hypcall.c
@@ -0,0 +1,53 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * KVM/MIPS: Hypercall handling.
+ *
+ * Copyright (C) 2015  Imagination Technologies Ltd.
+ */
+
+#include <linux/kernel.h>
+#include <linux/kvm_host.h>
+#include <linux/kvm_para.h>
+
+#define MAX_HYPCALL_ARGS	4
+
+enum emulation_result kvm_mips_emul_hypcall(struct kvm_vcpu *vcpu,
+					    union mips_instruction inst)
+{
+	unsigned int code = (inst.co_format.code >> 5) & 0x3ff;
+
+	kvm_debug("[%#lx] HYPCALL %#03x\n", vcpu->arch.pc, code);
+
+	switch (code) {
+	case 0:
+		return EMULATE_HYPERCALL;
+	default:
+		return EMULATE_FAIL;
+	};
+}
+
+static int kvm_mips_hypercall(struct kvm_vcpu *vcpu, unsigned long num,
+			      const unsigned long *args, unsigned long *hret)
+{
+	/* Report unimplemented hypercall to guest */
+	*hret = -KVM_ENOSYS;
+	return RESUME_GUEST;
+}
+
+int kvm_mips_handle_hypcall(struct kvm_vcpu *vcpu)
+{
+	unsigned long num, args[MAX_HYPCALL_ARGS];
+
+	/* read hypcall number and arguments */
+	num = vcpu->arch.gprs[2];	/* v0 */
+	args[0] = vcpu->arch.gprs[4];	/* a0 */
+	args[1] = vcpu->arch.gprs[5];	/* a1 */
+	args[2] = vcpu->arch.gprs[6];	/* a2 */
+	args[3] = vcpu->arch.gprs[7];	/* a3 */
+
+	return kvm_mips_hypercall(vcpu, num,
+				  args, &vcpu->arch.gprs[2] /* v0 */);
+}
diff --git a/arch/mips/kvm/interrupt.c b/arch/mips/kvm/interrupt.c
new file mode 100644
index 000000000..027794227
--- /dev/null
+++ b/arch/mips/kvm/interrupt.c
@@ -0,0 +1,56 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * KVM/MIPS: Interrupt delivery
+ *
+ * Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.
+ * Authors: Sanjay Lal <sanjayl@kymasys.com>
+ */
+
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/vmalloc.h>
+#include <linux/fs.h>
+#include <linux/memblock.h>
+#include <asm/page.h>
+#include <asm/cacheflush.h>
+
+#include <linux/kvm_host.h>
+
+#include "interrupt.h"
+
+void kvm_mips_deliver_interrupts(struct kvm_vcpu *vcpu, u32 cause)
+{
+	unsigned long *pending = &vcpu->arch.pending_exceptions;
+	unsigned long *pending_clr = &vcpu->arch.pending_exceptions_clr;
+	unsigned int priority;
+
+	if (!(*pending) && !(*pending_clr))
+		return;
+
+	priority = __ffs(*pending_clr);
+	while (priority <= MIPS_EXC_MAX) {
+		kvm_mips_callbacks->irq_clear(vcpu, priority, cause);
+
+		priority = find_next_bit(pending_clr,
+					 BITS_PER_BYTE * sizeof(*pending_clr),
+					 priority + 1);
+	}
+
+	priority = __ffs(*pending);
+	while (priority <= MIPS_EXC_MAX) {
+		kvm_mips_callbacks->irq_deliver(vcpu, priority, cause);
+
+		priority = find_next_bit(pending,
+					 BITS_PER_BYTE * sizeof(*pending),
+					 priority + 1);
+	}
+
+}
+
+int kvm_mips_pending_timer(struct kvm_vcpu *vcpu)
+{
+	return test_bit(MIPS_EXC_INT_TIMER, &vcpu->arch.pending_exceptions);
+}
diff --git a/arch/mips/kvm/interrupt.h b/arch/mips/kvm/interrupt.h
new file mode 100644
index 000000000..e529ea2bb
--- /dev/null
+++ b/arch/mips/kvm/interrupt.h
@@ -0,0 +1,39 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * KVM/MIPS: Interrupts
+ * Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.
+ * Authors: Sanjay Lal <sanjayl@kymasys.com>
+ */
+
+/*
+ * MIPS Exception Priorities, exceptions (including interrupts) are queued up
+ * for the guest in the order specified by their priorities
+ */
+
+#define MIPS_EXC_RESET              0
+#define MIPS_EXC_SRESET             1
+#define MIPS_EXC_DEBUG_ST           2
+#define MIPS_EXC_DEBUG              3
+#define MIPS_EXC_DDB                4
+#define MIPS_EXC_NMI                5
+#define MIPS_EXC_MCHK               6
+#define MIPS_EXC_INT_TIMER          7
+#define MIPS_EXC_INT_IO_1           8
+#define MIPS_EXC_INT_IO_2           9
+#define MIPS_EXC_EXECUTE            10
+#define MIPS_EXC_INT_IPI_1          11
+#define MIPS_EXC_INT_IPI_2          12
+#define MIPS_EXC_MAX                13
+/* XXXSL More to follow */
+
+#define C_TI        (_ULCAST_(1) << 30)
+
+extern u32 *kvm_priority_to_irq;
+u32 kvm_irq_to_priority(u32 irq);
+
+int kvm_mips_pending_timer(struct kvm_vcpu *vcpu);
+
+void kvm_mips_deliver_interrupts(struct kvm_vcpu *vcpu, u32 cause);
diff --git a/arch/mips/kvm/loongson_ipi.c b/arch/mips/kvm/loongson_ipi.c
new file mode 100644
index 000000000..5d53f32d8
--- /dev/null
+++ b/arch/mips/kvm/loongson_ipi.c
@@ -0,0 +1,214 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Loongson-3 Virtual IPI interrupt support.
+ *
+ * Copyright (C) 2019  Loongson Technologies, Inc.  All rights reserved.
+ *
+ * Authors: Chen Zhu <zhuchen@loongson.cn>
+ * Authors: Huacai Chen <chenhc@lemote.com>
+ */
+
+#include <linux/kvm_host.h>
+
+#define IPI_BASE            0x3ff01000ULL
+
+#define CORE0_STATUS_OFF       0x000
+#define CORE0_EN_OFF           0x004
+#define CORE0_SET_OFF          0x008
+#define CORE0_CLEAR_OFF        0x00c
+#define CORE0_BUF_20           0x020
+#define CORE0_BUF_28           0x028
+#define CORE0_BUF_30           0x030
+#define CORE0_BUF_38           0x038
+
+#define CORE1_STATUS_OFF       0x100
+#define CORE1_EN_OFF           0x104
+#define CORE1_SET_OFF          0x108
+#define CORE1_CLEAR_OFF        0x10c
+#define CORE1_BUF_20           0x120
+#define CORE1_BUF_28           0x128
+#define CORE1_BUF_30           0x130
+#define CORE1_BUF_38           0x138
+
+#define CORE2_STATUS_OFF       0x200
+#define CORE2_EN_OFF           0x204
+#define CORE2_SET_OFF          0x208
+#define CORE2_CLEAR_OFF        0x20c
+#define CORE2_BUF_20           0x220
+#define CORE2_BUF_28           0x228
+#define CORE2_BUF_30           0x230
+#define CORE2_BUF_38           0x238
+
+#define CORE3_STATUS_OFF       0x300
+#define CORE3_EN_OFF           0x304
+#define CORE3_SET_OFF          0x308
+#define CORE3_CLEAR_OFF        0x30c
+#define CORE3_BUF_20           0x320
+#define CORE3_BUF_28           0x328
+#define CORE3_BUF_30           0x330
+#define CORE3_BUF_38           0x338
+
+static int loongson_vipi_read(struct loongson_kvm_ipi *ipi,
+				gpa_t addr, int len, void *val)
+{
+	uint32_t core = (addr >> 8) & 3;
+	uint32_t node = (addr >> 44) & 3;
+	uint32_t id = core + node * 4;
+	uint64_t offset = addr & 0xff;
+	void *pbuf;
+	struct ipi_state *s = &(ipi->ipistate[id]);
+
+	BUG_ON(offset & (len - 1));
+
+	switch (offset) {
+	case CORE0_STATUS_OFF:
+		*(uint64_t *)val = s->status;
+		break;
+
+	case CORE0_EN_OFF:
+		*(uint64_t *)val = s->en;
+		break;
+
+	case CORE0_SET_OFF:
+		*(uint64_t *)val = 0;
+		break;
+
+	case CORE0_CLEAR_OFF:
+		*(uint64_t *)val = 0;
+		break;
+
+	case CORE0_BUF_20 ... CORE0_BUF_38:
+		pbuf = (void *)s->buf + (offset - 0x20);
+		if (len == 8)
+			*(uint64_t *)val = *(uint64_t *)pbuf;
+		else /* Assume len == 4 */
+			*(uint32_t *)val = *(uint32_t *)pbuf;
+		break;
+
+	default:
+		pr_notice("%s with unknown addr %llx\n", __func__, addr);
+		break;
+	}
+
+	return 0;
+}
+
+static int loongson_vipi_write(struct loongson_kvm_ipi *ipi,
+				gpa_t addr, int len, const void *val)
+{
+	uint32_t core = (addr >> 8) & 3;
+	uint32_t node = (addr >> 44) & 3;
+	uint32_t id = core + node * 4;
+	uint64_t data, offset = addr & 0xff;
+	void *pbuf;
+	struct kvm *kvm = ipi->kvm;
+	struct kvm_mips_interrupt irq;
+	struct ipi_state *s = &(ipi->ipistate[id]);
+
+	data = *(uint64_t *)val;
+	BUG_ON(offset & (len - 1));
+
+	switch (offset) {
+	case CORE0_STATUS_OFF:
+		break;
+
+	case CORE0_EN_OFF:
+		s->en = data;
+		break;
+
+	case CORE0_SET_OFF:
+		s->status |= data;
+		irq.cpu = id;
+		irq.irq = 6;
+		kvm_vcpu_ioctl_interrupt(kvm_get_vcpu(kvm, id), &irq);
+		break;
+
+	case CORE0_CLEAR_OFF:
+		s->status &= ~data;
+		if (!s->status) {
+			irq.cpu = id;
+			irq.irq = -6;
+			kvm_vcpu_ioctl_interrupt(kvm_get_vcpu(kvm, id), &irq);
+		}
+		break;
+
+	case CORE0_BUF_20 ... CORE0_BUF_38:
+		pbuf = (void *)s->buf + (offset - 0x20);
+		if (len == 8)
+			*(uint64_t *)pbuf = (uint64_t)data;
+		else /* Assume len == 4 */
+			*(uint32_t *)pbuf = (uint32_t)data;
+		break;
+
+	default:
+		pr_notice("%s with unknown addr %llx\n", __func__, addr);
+		break;
+	}
+
+	return 0;
+}
+
+static int kvm_ipi_read(struct kvm_vcpu *vcpu, struct kvm_io_device *dev,
+			gpa_t addr, int len, void *val)
+{
+	unsigned long flags;
+	struct loongson_kvm_ipi *ipi;
+	struct ipi_io_device *ipi_device;
+
+	ipi_device = container_of(dev, struct ipi_io_device, device);
+	ipi = ipi_device->ipi;
+
+	spin_lock_irqsave(&ipi->lock, flags);
+	loongson_vipi_read(ipi, addr, len, val);
+	spin_unlock_irqrestore(&ipi->lock, flags);
+
+	return 0;
+}
+
+static int kvm_ipi_write(struct kvm_vcpu *vcpu, struct kvm_io_device *dev,
+			gpa_t addr, int len, const void *val)
+{
+	unsigned long flags;
+	struct loongson_kvm_ipi *ipi;
+	struct ipi_io_device *ipi_device;
+
+	ipi_device = container_of(dev, struct ipi_io_device, device);
+	ipi = ipi_device->ipi;
+
+	spin_lock_irqsave(&ipi->lock, flags);
+	loongson_vipi_write(ipi, addr, len, val);
+	spin_unlock_irqrestore(&ipi->lock, flags);
+
+	return 0;
+}
+
+static const struct kvm_io_device_ops kvm_ipi_ops = {
+	.read     = kvm_ipi_read,
+	.write    = kvm_ipi_write,
+};
+
+void kvm_init_loongson_ipi(struct kvm *kvm)
+{
+	int i;
+	unsigned long addr;
+	struct loongson_kvm_ipi *s;
+	struct kvm_io_device *device;
+
+	s = &kvm->arch.ipi;
+	s->kvm = kvm;
+	spin_lock_init(&s->lock);
+
+	/*
+	 * Initialize IPI device
+	 */
+	for (i = 0; i < 4; i++) {
+		device = &s->dev_ipi[i].device;
+		kvm_iodevice_init(device, &kvm_ipi_ops);
+		addr = (((unsigned long)i) << 44) + IPI_BASE;
+		mutex_lock(&kvm->slots_lock);
+		kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, addr, 0x400, device);
+		mutex_unlock(&kvm->slots_lock);
+		s->dev_ipi[i].ipi = s;
+		s->dev_ipi[i].node_id = i;
+	}
+}
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
new file mode 100644
index 000000000..231ac052b
--- /dev/null
+++ b/arch/mips/kvm/mips.c
@@ -0,0 +1,1646 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * KVM/MIPS: MIPS specific KVM APIs
+ *
+ * Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.
+ * Authors: Sanjay Lal <sanjayl@kymasys.com>
+ */
+
+#include <linux/bitops.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/kdebug.h>
+#include <linux/module.h>
+#include <linux/uaccess.h>
+#include <linux/vmalloc.h>
+#include <linux/sched/signal.h>
+#include <linux/fs.h>
+#include <linux/memblock.h>
+#include <linux/pgtable.h>
+
+#include <asm/fpu.h>
+#include <asm/page.h>
+#include <asm/cacheflush.h>
+#include <asm/mmu_context.h>
+#include <asm/pgalloc.h>
+
+#include <linux/kvm_host.h>
+
+#include "interrupt.h"
+
+#define CREATE_TRACE_POINTS
+#include "trace.h"
+
+#ifndef VECTORSPACING
+#define VECTORSPACING 0x100	/* for EI/VI mode */
+#endif
+
+const struct _kvm_stats_desc kvm_vm_stats_desc[] = {
+	KVM_GENERIC_VM_STATS()
+};
+
+const struct kvm_stats_header kvm_vm_stats_header = {
+	.name_size = KVM_STATS_NAME_SIZE,
+	.num_desc = ARRAY_SIZE(kvm_vm_stats_desc),
+	.id_offset = sizeof(struct kvm_stats_header),
+	.desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
+	.data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
+		       sizeof(kvm_vm_stats_desc),
+};
+
+const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = {
+	KVM_GENERIC_VCPU_STATS(),
+	STATS_DESC_COUNTER(VCPU, wait_exits),
+	STATS_DESC_COUNTER(VCPU, cache_exits),
+	STATS_DESC_COUNTER(VCPU, signal_exits),
+	STATS_DESC_COUNTER(VCPU, int_exits),
+	STATS_DESC_COUNTER(VCPU, cop_unusable_exits),
+	STATS_DESC_COUNTER(VCPU, tlbmod_exits),
+	STATS_DESC_COUNTER(VCPU, tlbmiss_ld_exits),
+	STATS_DESC_COUNTER(VCPU, tlbmiss_st_exits),
+	STATS_DESC_COUNTER(VCPU, addrerr_st_exits),
+	STATS_DESC_COUNTER(VCPU, addrerr_ld_exits),
+	STATS_DESC_COUNTER(VCPU, syscall_exits),
+	STATS_DESC_COUNTER(VCPU, resvd_inst_exits),
+	STATS_DESC_COUNTER(VCPU, break_inst_exits),
+	STATS_DESC_COUNTER(VCPU, trap_inst_exits),
+	STATS_DESC_COUNTER(VCPU, msa_fpe_exits),
+	STATS_DESC_COUNTER(VCPU, fpe_exits),
+	STATS_DESC_COUNTER(VCPU, msa_disabled_exits),
+	STATS_DESC_COUNTER(VCPU, flush_dcache_exits),
+	STATS_DESC_COUNTER(VCPU, vz_gpsi_exits),
+	STATS_DESC_COUNTER(VCPU, vz_gsfc_exits),
+	STATS_DESC_COUNTER(VCPU, vz_hc_exits),
+	STATS_DESC_COUNTER(VCPU, vz_grr_exits),
+	STATS_DESC_COUNTER(VCPU, vz_gva_exits),
+	STATS_DESC_COUNTER(VCPU, vz_ghfc_exits),
+	STATS_DESC_COUNTER(VCPU, vz_gpa_exits),
+	STATS_DESC_COUNTER(VCPU, vz_resvd_exits),
+#ifdef CONFIG_CPU_LOONGSON64
+	STATS_DESC_COUNTER(VCPU, vz_cpucfg_exits),
+#endif
+};
+
+const struct kvm_stats_header kvm_vcpu_stats_header = {
+	.name_size = KVM_STATS_NAME_SIZE,
+	.num_desc = ARRAY_SIZE(kvm_vcpu_stats_desc),
+	.id_offset = sizeof(struct kvm_stats_header),
+	.desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
+	.data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
+		       sizeof(kvm_vcpu_stats_desc),
+};
+
+bool kvm_trace_guest_mode_change;
+
+int kvm_guest_mode_change_trace_reg(void)
+{
+	kvm_trace_guest_mode_change = true;
+	return 0;
+}
+
+void kvm_guest_mode_change_trace_unreg(void)
+{
+	kvm_trace_guest_mode_change = false;
+}
+
+/*
+ * XXXKYMA: We are simulatoring a processor that has the WII bit set in
+ * Config7, so we are "runnable" if interrupts are pending
+ */
+int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
+{
+	return !!(vcpu->arch.pending_exceptions);
+}
+
+bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
+{
+	return false;
+}
+
+int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
+{
+	return 1;
+}
+
+int kvm_arch_hardware_enable(void)
+{
+	return kvm_mips_callbacks->hardware_enable();
+}
+
+void kvm_arch_hardware_disable(void)
+{
+	kvm_mips_callbacks->hardware_disable();
+}
+
+extern void kvm_init_loongson_ipi(struct kvm *kvm);
+
+int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
+{
+	switch (type) {
+	case KVM_VM_MIPS_AUTO:
+		break;
+	case KVM_VM_MIPS_VZ:
+		break;
+	default:
+		/* Unsupported KVM type */
+		return -EINVAL;
+	}
+
+	/* Allocate page table to map GPA -> RPA */
+	kvm->arch.gpa_mm.pgd = kvm_pgd_alloc();
+	if (!kvm->arch.gpa_mm.pgd)
+		return -ENOMEM;
+
+#ifdef CONFIG_CPU_LOONGSON64
+	kvm_init_loongson_ipi(kvm);
+#endif
+
+	return 0;
+}
+
+static void kvm_mips_free_gpa_pt(struct kvm *kvm)
+{
+	/* It should always be safe to remove after flushing the whole range */
+	WARN_ON(!kvm_mips_flush_gpa_pt(kvm, 0, ~0));
+	pgd_free(NULL, kvm->arch.gpa_mm.pgd);
+}
+
+void kvm_arch_destroy_vm(struct kvm *kvm)
+{
+	kvm_destroy_vcpus(kvm);
+	kvm_mips_free_gpa_pt(kvm);
+}
+
+long kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl,
+			unsigned long arg)
+{
+	return -ENOIOCTLCMD;
+}
+
+void kvm_arch_flush_shadow_all(struct kvm *kvm)
+{
+	/* Flush whole GPA */
+	kvm_mips_flush_gpa_pt(kvm, 0, ~0);
+	kvm_flush_remote_tlbs(kvm);
+}
+
+void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
+				   struct kvm_memory_slot *slot)
+{
+	/*
+	 * The slot has been made invalid (ready for moving or deletion), so we
+	 * need to ensure that it can no longer be accessed by any guest VCPUs.
+	 */
+
+	spin_lock(&kvm->mmu_lock);
+	/* Flush slot from GPA */
+	kvm_mips_flush_gpa_pt(kvm, slot->base_gfn,
+			      slot->base_gfn + slot->npages - 1);
+	kvm_flush_remote_tlbs_memslot(kvm, slot);
+	spin_unlock(&kvm->mmu_lock);
+}
+
+int kvm_arch_prepare_memory_region(struct kvm *kvm,
+				   const struct kvm_memory_slot *old,
+				   struct kvm_memory_slot *new,
+				   enum kvm_mr_change change)
+{
+	return 0;
+}
+
+void kvm_arch_commit_memory_region(struct kvm *kvm,
+				   struct kvm_memory_slot *old,
+				   const struct kvm_memory_slot *new,
+				   enum kvm_mr_change change)
+{
+	int needs_flush;
+
+	/*
+	 * If dirty page logging is enabled, write protect all pages in the slot
+	 * ready for dirty logging.
+	 *
+	 * There is no need to do this in any of the following cases:
+	 * CREATE:	No dirty mappings will already exist.
+	 * MOVE/DELETE:	The old mappings will already have been cleaned up by
+	 *		kvm_arch_flush_shadow_memslot()
+	 */
+	if (change == KVM_MR_FLAGS_ONLY &&
+	    (!(old->flags & KVM_MEM_LOG_DIRTY_PAGES) &&
+	     new->flags & KVM_MEM_LOG_DIRTY_PAGES)) {
+		spin_lock(&kvm->mmu_lock);
+		/* Write protect GPA page table entries */
+		needs_flush = kvm_mips_mkclean_gpa_pt(kvm, new->base_gfn,
+					new->base_gfn + new->npages - 1);
+		if (needs_flush)
+			kvm_flush_remote_tlbs_memslot(kvm, new);
+		spin_unlock(&kvm->mmu_lock);
+	}
+}
+
+static inline void dump_handler(const char *symbol, void *start, void *end)
+{
+	u32 *p;
+
+	pr_debug("LEAF(%s)\n", symbol);
+
+	pr_debug("\t.set push\n");
+	pr_debug("\t.set noreorder\n");
+
+	for (p = start; p < (u32 *)end; ++p)
+		pr_debug("\t.word\t0x%08x\t\t# %p\n", *p, p);
+
+	pr_debug("\t.set\tpop\n");
+
+	pr_debug("\tEND(%s)\n", symbol);
+}
+
+/* low level hrtimer wake routine */
+static enum hrtimer_restart kvm_mips_comparecount_wakeup(struct hrtimer *timer)
+{
+	struct kvm_vcpu *vcpu;
+
+	vcpu = container_of(timer, struct kvm_vcpu, arch.comparecount_timer);
+
+	kvm_mips_callbacks->queue_timer_int(vcpu);
+
+	vcpu->arch.wait = 0;
+	rcuwait_wake_up(&vcpu->wait);
+
+	return kvm_mips_count_timeout(vcpu);
+}
+
+int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
+{
+	return 0;
+}
+
+int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
+{
+	int err, size;
+	void *gebase, *p, *handler, *refill_start, *refill_end;
+	int i;
+
+	kvm_debug("kvm @ %p: create cpu %d at %p\n",
+		  vcpu->kvm, vcpu->vcpu_id, vcpu);
+
+	err = kvm_mips_callbacks->vcpu_init(vcpu);
+	if (err)
+		return err;
+
+	hrtimer_init(&vcpu->arch.comparecount_timer, CLOCK_MONOTONIC,
+		     HRTIMER_MODE_REL);
+	vcpu->arch.comparecount_timer.function = kvm_mips_comparecount_wakeup;
+
+	/*
+	 * Allocate space for host mode exception handlers that handle
+	 * guest mode exits
+	 */
+	if (cpu_has_veic || cpu_has_vint)
+		size = 0x200 + VECTORSPACING * 64;
+	else
+		size = 0x4000;
+
+	gebase = kzalloc(ALIGN(size, PAGE_SIZE), GFP_KERNEL);
+
+	if (!gebase) {
+		err = -ENOMEM;
+		goto out_uninit_vcpu;
+	}
+	kvm_debug("Allocated %d bytes for KVM Exception Handlers @ %p\n",
+		  ALIGN(size, PAGE_SIZE), gebase);
+
+	/*
+	 * Check new ebase actually fits in CP0_EBase. The lack of a write gate
+	 * limits us to the low 512MB of physical address space. If the memory
+	 * we allocate is out of range, just give up now.
+	 */
+	if (!cpu_has_ebase_wg && virt_to_phys(gebase) >= 0x20000000) {
+		kvm_err("CP0_EBase.WG required for guest exception base %pK\n",
+			gebase);
+		err = -ENOMEM;
+		goto out_free_gebase;
+	}
+
+	/* Save new ebase */
+	vcpu->arch.guest_ebase = gebase;
+
+	/* Build guest exception vectors dynamically in unmapped memory */
+	handler = gebase + 0x2000;
+
+	/* TLB refill (or XTLB refill on 64-bit VZ where KX=1) */
+	refill_start = gebase;
+	if (IS_ENABLED(CONFIG_64BIT))
+		refill_start += 0x080;
+	refill_end = kvm_mips_build_tlb_refill_exception(refill_start, handler);
+
+	/* General Exception Entry point */
+	kvm_mips_build_exception(gebase + 0x180, handler);
+
+	/* For vectored interrupts poke the exception code @ all offsets 0-7 */
+	for (i = 0; i < 8; i++) {
+		kvm_debug("L1 Vectored handler @ %p\n",
+			  gebase + 0x200 + (i * VECTORSPACING));
+		kvm_mips_build_exception(gebase + 0x200 + i * VECTORSPACING,
+					 handler);
+	}
+
+	/* General exit handler */
+	p = handler;
+	p = kvm_mips_build_exit(p);
+
+	/* Guest entry routine */
+	vcpu->arch.vcpu_run = p;
+	p = kvm_mips_build_vcpu_run(p);
+
+	/* Dump the generated code */
+	pr_debug("#include <asm/asm.h>\n");
+	pr_debug("#include <asm/regdef.h>\n");
+	pr_debug("\n");
+	dump_handler("kvm_vcpu_run", vcpu->arch.vcpu_run, p);
+	dump_handler("kvm_tlb_refill", refill_start, refill_end);
+	dump_handler("kvm_gen_exc", gebase + 0x180, gebase + 0x200);
+	dump_handler("kvm_exit", gebase + 0x2000, vcpu->arch.vcpu_run);
+
+	/* Invalidate the icache for these ranges */
+	flush_icache_range((unsigned long)gebase,
+			   (unsigned long)gebase + ALIGN(size, PAGE_SIZE));
+
+	/* Init */
+	vcpu->arch.last_sched_cpu = -1;
+	vcpu->arch.last_exec_cpu = -1;
+
+	/* Initial guest state */
+	err = kvm_mips_callbacks->vcpu_setup(vcpu);
+	if (err)
+		goto out_free_gebase;
+
+	return 0;
+
+out_free_gebase:
+	kfree(gebase);
+out_uninit_vcpu:
+	kvm_mips_callbacks->vcpu_uninit(vcpu);
+	return err;
+}
+
+void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
+{
+	hrtimer_cancel(&vcpu->arch.comparecount_timer);
+
+	kvm_mips_dump_stats(vcpu);
+
+	kvm_mmu_free_memory_caches(vcpu);
+	kfree(vcpu->arch.guest_ebase);
+
+	kvm_mips_callbacks->vcpu_uninit(vcpu);
+}
+
+int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
+					struct kvm_guest_debug *dbg)
+{
+	return -ENOIOCTLCMD;
+}
+
+/*
+ * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while
+ * the vCPU is running.
+ *
+ * This must be noinstr as instrumentation may make use of RCU, and this is not
+ * safe during the EQS.
+ */
+static int noinstr kvm_mips_vcpu_enter_exit(struct kvm_vcpu *vcpu)
+{
+	int ret;
+
+	guest_state_enter_irqoff();
+	ret = kvm_mips_callbacks->vcpu_run(vcpu);
+	guest_state_exit_irqoff();
+
+	return ret;
+}
+
+int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
+{
+	int r = -EINTR;
+
+	vcpu_load(vcpu);
+
+	kvm_sigset_activate(vcpu);
+
+	if (vcpu->mmio_needed) {
+		if (!vcpu->mmio_is_write)
+			kvm_mips_complete_mmio_load(vcpu);
+		vcpu->mmio_needed = 0;
+	}
+
+	if (vcpu->run->immediate_exit)
+		goto out;
+
+	lose_fpu(1);
+
+	local_irq_disable();
+	guest_timing_enter_irqoff();
+	trace_kvm_enter(vcpu);
+
+	/*
+	 * Make sure the read of VCPU requests in vcpu_run() callback is not
+	 * reordered ahead of the write to vcpu->mode, or we could miss a TLB
+	 * flush request while the requester sees the VCPU as outside of guest
+	 * mode and not needing an IPI.
+	 */
+	smp_store_mb(vcpu->mode, IN_GUEST_MODE);
+
+	r = kvm_mips_vcpu_enter_exit(vcpu);
+
+	/*
+	 * We must ensure that any pending interrupts are taken before
+	 * we exit guest timing so that timer ticks are accounted as
+	 * guest time. Transiently unmask interrupts so that any
+	 * pending interrupts are taken.
+	 *
+	 * TODO: is there a barrier which ensures that pending interrupts are
+	 * recognised? Currently this just hopes that the CPU takes any pending
+	 * interrupts between the enable and disable.
+	 */
+	local_irq_enable();
+	local_irq_disable();
+
+	trace_kvm_out(vcpu);
+	guest_timing_exit_irqoff();
+	local_irq_enable();
+
+out:
+	kvm_sigset_deactivate(vcpu);
+
+	vcpu_put(vcpu);
+	return r;
+}
+
+int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
+			     struct kvm_mips_interrupt *irq)
+{
+	int intr = (int)irq->irq;
+	struct kvm_vcpu *dvcpu = NULL;
+
+	if (intr == kvm_priority_to_irq[MIPS_EXC_INT_IPI_1] ||
+	    intr == kvm_priority_to_irq[MIPS_EXC_INT_IPI_2] ||
+	    intr == (-kvm_priority_to_irq[MIPS_EXC_INT_IPI_1]) ||
+	    intr == (-kvm_priority_to_irq[MIPS_EXC_INT_IPI_2]))
+		kvm_debug("%s: CPU: %d, INTR: %d\n", __func__, irq->cpu,
+			  (int)intr);
+
+	if (irq->cpu == -1)
+		dvcpu = vcpu;
+	else
+		dvcpu = kvm_get_vcpu(vcpu->kvm, irq->cpu);
+
+	if (intr == 2 || intr == 3 || intr == 4 || intr == 6) {
+		kvm_mips_callbacks->queue_io_int(dvcpu, irq);
+
+	} else if (intr == -2 || intr == -3 || intr == -4 || intr == -6) {
+		kvm_mips_callbacks->dequeue_io_int(dvcpu, irq);
+	} else {
+		kvm_err("%s: invalid interrupt ioctl (%d:%d)\n", __func__,
+			irq->cpu, irq->irq);
+		return -EINVAL;
+	}
+
+	dvcpu->arch.wait = 0;
+
+	rcuwait_wake_up(&dvcpu->wait);
+
+	return 0;
+}
+
+int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
+				    struct kvm_mp_state *mp_state)
+{
+	return -ENOIOCTLCMD;
+}
+
+int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
+				    struct kvm_mp_state *mp_state)
+{
+	return -ENOIOCTLCMD;
+}
+
+static u64 kvm_mips_get_one_regs[] = {
+	KVM_REG_MIPS_R0,
+	KVM_REG_MIPS_R1,
+	KVM_REG_MIPS_R2,
+	KVM_REG_MIPS_R3,
+	KVM_REG_MIPS_R4,
+	KVM_REG_MIPS_R5,
+	KVM_REG_MIPS_R6,
+	KVM_REG_MIPS_R7,
+	KVM_REG_MIPS_R8,
+	KVM_REG_MIPS_R9,
+	KVM_REG_MIPS_R10,
+	KVM_REG_MIPS_R11,
+	KVM_REG_MIPS_R12,
+	KVM_REG_MIPS_R13,
+	KVM_REG_MIPS_R14,
+	KVM_REG_MIPS_R15,
+	KVM_REG_MIPS_R16,
+	KVM_REG_MIPS_R17,
+	KVM_REG_MIPS_R18,
+	KVM_REG_MIPS_R19,
+	KVM_REG_MIPS_R20,
+	KVM_REG_MIPS_R21,
+	KVM_REG_MIPS_R22,
+	KVM_REG_MIPS_R23,
+	KVM_REG_MIPS_R24,
+	KVM_REG_MIPS_R25,
+	KVM_REG_MIPS_R26,
+	KVM_REG_MIPS_R27,
+	KVM_REG_MIPS_R28,
+	KVM_REG_MIPS_R29,
+	KVM_REG_MIPS_R30,
+	KVM_REG_MIPS_R31,
+
+#ifndef CONFIG_CPU_MIPSR6
+	KVM_REG_MIPS_HI,
+	KVM_REG_MIPS_LO,
+#endif
+	KVM_REG_MIPS_PC,
+};
+
+static u64 kvm_mips_get_one_regs_fpu[] = {
+	KVM_REG_MIPS_FCR_IR,
+	KVM_REG_MIPS_FCR_CSR,
+};
+
+static u64 kvm_mips_get_one_regs_msa[] = {
+	KVM_REG_MIPS_MSA_IR,
+	KVM_REG_MIPS_MSA_CSR,
+};
+
+static unsigned long kvm_mips_num_regs(struct kvm_vcpu *vcpu)
+{
+	unsigned long ret;
+
+	ret = ARRAY_SIZE(kvm_mips_get_one_regs);
+	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
+		ret += ARRAY_SIZE(kvm_mips_get_one_regs_fpu) + 48;
+		/* odd doubles */
+		if (boot_cpu_data.fpu_id & MIPS_FPIR_F64)
+			ret += 16;
+	}
+	if (kvm_mips_guest_can_have_msa(&vcpu->arch))
+		ret += ARRAY_SIZE(kvm_mips_get_one_regs_msa) + 32;
+	ret += kvm_mips_callbacks->num_regs(vcpu);
+
+	return ret;
+}
+
+static int kvm_mips_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices)
+{
+	u64 index;
+	unsigned int i;
+
+	if (copy_to_user(indices, kvm_mips_get_one_regs,
+			 sizeof(kvm_mips_get_one_regs)))
+		return -EFAULT;
+	indices += ARRAY_SIZE(kvm_mips_get_one_regs);
+
+	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
+		if (copy_to_user(indices, kvm_mips_get_one_regs_fpu,
+				 sizeof(kvm_mips_get_one_regs_fpu)))
+			return -EFAULT;
+		indices += ARRAY_SIZE(kvm_mips_get_one_regs_fpu);
+
+		for (i = 0; i < 32; ++i) {
+			index = KVM_REG_MIPS_FPR_32(i);
+			if (copy_to_user(indices, &index, sizeof(index)))
+				return -EFAULT;
+			++indices;
+
+			/* skip odd doubles if no F64 */
+			if (i & 1 && !(boot_cpu_data.fpu_id & MIPS_FPIR_F64))
+				continue;
+
+			index = KVM_REG_MIPS_FPR_64(i);
+			if (copy_to_user(indices, &index, sizeof(index)))
+				return -EFAULT;
+			++indices;
+		}
+	}
+
+	if (kvm_mips_guest_can_have_msa(&vcpu->arch)) {
+		if (copy_to_user(indices, kvm_mips_get_one_regs_msa,
+				 sizeof(kvm_mips_get_one_regs_msa)))
+			return -EFAULT;
+		indices += ARRAY_SIZE(kvm_mips_get_one_regs_msa);
+
+		for (i = 0; i < 32; ++i) {
+			index = KVM_REG_MIPS_VEC_128(i);
+			if (copy_to_user(indices, &index, sizeof(index)))
+				return -EFAULT;
+			++indices;
+		}
+	}
+
+	return kvm_mips_callbacks->copy_reg_indices(vcpu, indices);
+}
+
+static int kvm_mips_get_reg(struct kvm_vcpu *vcpu,
+			    const struct kvm_one_reg *reg)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
+	int ret;
+	s64 v;
+	s64 vs[2];
+	unsigned int idx;
+
+	switch (reg->id) {
+	/* General purpose registers */
+	case KVM_REG_MIPS_R0 ... KVM_REG_MIPS_R31:
+		v = (long)vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0];
+		break;
+#ifndef CONFIG_CPU_MIPSR6
+	case KVM_REG_MIPS_HI:
+		v = (long)vcpu->arch.hi;
+		break;
+	case KVM_REG_MIPS_LO:
+		v = (long)vcpu->arch.lo;
+		break;
+#endif
+	case KVM_REG_MIPS_PC:
+		v = (long)vcpu->arch.pc;
+		break;
+
+	/* Floating point registers */
+	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
+		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
+			return -EINVAL;
+		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
+		/* Odd singles in top of even double when FR=0 */
+		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
+			v = get_fpr32(&fpu->fpr[idx], 0);
+		else
+			v = get_fpr32(&fpu->fpr[idx & ~1], idx & 1);
+		break;
+	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
+		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
+			return -EINVAL;
+		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
+		/* Can't access odd doubles in FR=0 mode */
+		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
+			return -EINVAL;
+		v = get_fpr64(&fpu->fpr[idx], 0);
+		break;
+	case KVM_REG_MIPS_FCR_IR:
+		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
+			return -EINVAL;
+		v = boot_cpu_data.fpu_id;
+		break;
+	case KVM_REG_MIPS_FCR_CSR:
+		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
+			return -EINVAL;
+		v = fpu->fcr31;
+		break;
+
+	/* MIPS SIMD Architecture (MSA) registers */
+	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
+		if (!kvm_mips_guest_has_msa(&vcpu->arch))
+			return -EINVAL;
+		/* Can't access MSA registers in FR=0 mode */
+		if (!(kvm_read_c0_guest_status(cop0) & ST0_FR))
+			return -EINVAL;
+		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+		/* least significant byte first */
+		vs[0] = get_fpr64(&fpu->fpr[idx], 0);
+		vs[1] = get_fpr64(&fpu->fpr[idx], 1);
+#else
+		/* most significant byte first */
+		vs[0] = get_fpr64(&fpu->fpr[idx], 1);
+		vs[1] = get_fpr64(&fpu->fpr[idx], 0);
+#endif
+		break;
+	case KVM_REG_MIPS_MSA_IR:
+		if (!kvm_mips_guest_has_msa(&vcpu->arch))
+			return -EINVAL;
+		v = boot_cpu_data.msa_id;
+		break;
+	case KVM_REG_MIPS_MSA_CSR:
+		if (!kvm_mips_guest_has_msa(&vcpu->arch))
+			return -EINVAL;
+		v = fpu->msacsr;
+		break;
+
+	/* registers to be handled specially */
+	default:
+		ret = kvm_mips_callbacks->get_one_reg(vcpu, reg, &v);
+		if (ret)
+			return ret;
+		break;
+	}
+	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
+		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
+
+		return put_user(v, uaddr64);
+	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
+		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
+		u32 v32 = (u32)v;
+
+		return put_user(v32, uaddr32);
+	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
+		void __user *uaddr = (void __user *)(long)reg->addr;
+
+		return copy_to_user(uaddr, vs, 16) ? -EFAULT : 0;
+	} else {
+		return -EINVAL;
+	}
+}
+
+static int kvm_mips_set_reg(struct kvm_vcpu *vcpu,
+			    const struct kvm_one_reg *reg)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
+	s64 v;
+	s64 vs[2];
+	unsigned int idx;
+
+	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
+		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
+
+		if (get_user(v, uaddr64) != 0)
+			return -EFAULT;
+	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
+		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
+		s32 v32;
+
+		if (get_user(v32, uaddr32) != 0)
+			return -EFAULT;
+		v = (s64)v32;
+	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
+		void __user *uaddr = (void __user *)(long)reg->addr;
+
+		return copy_from_user(vs, uaddr, 16) ? -EFAULT : 0;
+	} else {
+		return -EINVAL;
+	}
+
+	switch (reg->id) {
+	/* General purpose registers */
+	case KVM_REG_MIPS_R0:
+		/* Silently ignore requests to set $0 */
+		break;
+	case KVM_REG_MIPS_R1 ... KVM_REG_MIPS_R31:
+		vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0] = v;
+		break;
+#ifndef CONFIG_CPU_MIPSR6
+	case KVM_REG_MIPS_HI:
+		vcpu->arch.hi = v;
+		break;
+	case KVM_REG_MIPS_LO:
+		vcpu->arch.lo = v;
+		break;
+#endif
+	case KVM_REG_MIPS_PC:
+		vcpu->arch.pc = v;
+		break;
+
+	/* Floating point registers */
+	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
+		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
+			return -EINVAL;
+		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
+		/* Odd singles in top of even double when FR=0 */
+		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
+			set_fpr32(&fpu->fpr[idx], 0, v);
+		else
+			set_fpr32(&fpu->fpr[idx & ~1], idx & 1, v);
+		break;
+	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
+		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
+			return -EINVAL;
+		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
+		/* Can't access odd doubles in FR=0 mode */
+		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
+			return -EINVAL;
+		set_fpr64(&fpu->fpr[idx], 0, v);
+		break;
+	case KVM_REG_MIPS_FCR_IR:
+		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
+			return -EINVAL;
+		/* Read-only */
+		break;
+	case KVM_REG_MIPS_FCR_CSR:
+		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
+			return -EINVAL;
+		fpu->fcr31 = v;
+		break;
+
+	/* MIPS SIMD Architecture (MSA) registers */
+	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
+		if (!kvm_mips_guest_has_msa(&vcpu->arch))
+			return -EINVAL;
+		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+		/* least significant byte first */
+		set_fpr64(&fpu->fpr[idx], 0, vs[0]);
+		set_fpr64(&fpu->fpr[idx], 1, vs[1]);
+#else
+		/* most significant byte first */
+		set_fpr64(&fpu->fpr[idx], 1, vs[0]);
+		set_fpr64(&fpu->fpr[idx], 0, vs[1]);
+#endif
+		break;
+	case KVM_REG_MIPS_MSA_IR:
+		if (!kvm_mips_guest_has_msa(&vcpu->arch))
+			return -EINVAL;
+		/* Read-only */
+		break;
+	case KVM_REG_MIPS_MSA_CSR:
+		if (!kvm_mips_guest_has_msa(&vcpu->arch))
+			return -EINVAL;
+		fpu->msacsr = v;
+		break;
+
+	/* registers to be handled specially */
+	default:
+		return kvm_mips_callbacks->set_one_reg(vcpu, reg, v);
+	}
+	return 0;
+}
+
+static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
+				     struct kvm_enable_cap *cap)
+{
+	int r = 0;
+
+	if (!kvm_vm_ioctl_check_extension(vcpu->kvm, cap->cap))
+		return -EINVAL;
+	if (cap->flags)
+		return -EINVAL;
+	if (cap->args[0])
+		return -EINVAL;
+
+	switch (cap->cap) {
+	case KVM_CAP_MIPS_FPU:
+		vcpu->arch.fpu_enabled = true;
+		break;
+	case KVM_CAP_MIPS_MSA:
+		vcpu->arch.msa_enabled = true;
+		break;
+	default:
+		r = -EINVAL;
+		break;
+	}
+
+	return r;
+}
+
+long kvm_arch_vcpu_async_ioctl(struct file *filp, unsigned int ioctl,
+			       unsigned long arg)
+{
+	struct kvm_vcpu *vcpu = filp->private_data;
+	void __user *argp = (void __user *)arg;
+
+	if (ioctl == KVM_INTERRUPT) {
+		struct kvm_mips_interrupt irq;
+
+		if (copy_from_user(&irq, argp, sizeof(irq)))
+			return -EFAULT;
+		kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,
+			  irq.irq);
+
+		return kvm_vcpu_ioctl_interrupt(vcpu, &irq);
+	}
+
+	return -ENOIOCTLCMD;
+}
+
+long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl,
+			 unsigned long arg)
+{
+	struct kvm_vcpu *vcpu = filp->private_data;
+	void __user *argp = (void __user *)arg;
+	long r;
+
+	vcpu_load(vcpu);
+
+	switch (ioctl) {
+	case KVM_SET_ONE_REG:
+	case KVM_GET_ONE_REG: {
+		struct kvm_one_reg reg;
+
+		r = -EFAULT;
+		if (copy_from_user(&reg, argp, sizeof(reg)))
+			break;
+		if (ioctl == KVM_SET_ONE_REG)
+			r = kvm_mips_set_reg(vcpu, &reg);
+		else
+			r = kvm_mips_get_reg(vcpu, &reg);
+		break;
+	}
+	case KVM_GET_REG_LIST: {
+		struct kvm_reg_list __user *user_list = argp;
+		struct kvm_reg_list reg_list;
+		unsigned n;
+
+		r = -EFAULT;
+		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
+			break;
+		n = reg_list.n;
+		reg_list.n = kvm_mips_num_regs(vcpu);
+		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
+			break;
+		r = -E2BIG;
+		if (n < reg_list.n)
+			break;
+		r = kvm_mips_copy_reg_indices(vcpu, user_list->reg);
+		break;
+	}
+	case KVM_ENABLE_CAP: {
+		struct kvm_enable_cap cap;
+
+		r = -EFAULT;
+		if (copy_from_user(&cap, argp, sizeof(cap)))
+			break;
+		r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
+		break;
+	}
+	default:
+		r = -ENOIOCTLCMD;
+	}
+
+	vcpu_put(vcpu);
+	return r;
+}
+
+void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
+{
+
+}
+
+int kvm_arch_flush_remote_tlbs(struct kvm *kvm)
+{
+	kvm_mips_callbacks->prepare_flush_shadow(kvm);
+	return 1;
+}
+
+int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
+{
+	int r;
+
+	switch (ioctl) {
+	default:
+		r = -ENOIOCTLCMD;
+	}
+
+	return r;
+}
+
+int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
+				  struct kvm_sregs *sregs)
+{
+	return -ENOIOCTLCMD;
+}
+
+int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
+				  struct kvm_sregs *sregs)
+{
+	return -ENOIOCTLCMD;
+}
+
+void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
+{
+}
+
+int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
+{
+	return -ENOIOCTLCMD;
+}
+
+int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
+{
+	return -ENOIOCTLCMD;
+}
+
+vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
+{
+	return VM_FAULT_SIGBUS;
+}
+
+int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
+{
+	int r;
+
+	switch (ext) {
+	case KVM_CAP_ONE_REG:
+	case KVM_CAP_ENABLE_CAP:
+	case KVM_CAP_READONLY_MEM:
+	case KVM_CAP_SYNC_MMU:
+	case KVM_CAP_IMMEDIATE_EXIT:
+		r = 1;
+		break;
+	case KVM_CAP_NR_VCPUS:
+		r = min_t(unsigned int, num_online_cpus(), KVM_MAX_VCPUS);
+		break;
+	case KVM_CAP_MAX_VCPUS:
+		r = KVM_MAX_VCPUS;
+		break;
+	case KVM_CAP_MAX_VCPU_ID:
+		r = KVM_MAX_VCPU_IDS;
+		break;
+	case KVM_CAP_MIPS_FPU:
+		/* We don't handle systems with inconsistent cpu_has_fpu */
+		r = !!raw_cpu_has_fpu;
+		break;
+	case KVM_CAP_MIPS_MSA:
+		/*
+		 * We don't support MSA vector partitioning yet:
+		 * 1) It would require explicit support which can't be tested
+		 *    yet due to lack of support in current hardware.
+		 * 2) It extends the state that would need to be saved/restored
+		 *    by e.g. QEMU for migration.
+		 *
+		 * When vector partitioning hardware becomes available, support
+		 * could be added by requiring a flag when enabling
+		 * KVM_CAP_MIPS_MSA capability to indicate that userland knows
+		 * to save/restore the appropriate extra state.
+		 */
+		r = cpu_has_msa && !(boot_cpu_data.msa_id & MSA_IR_WRPF);
+		break;
+	default:
+		r = kvm_mips_callbacks->check_extension(kvm, ext);
+		break;
+	}
+	return r;
+}
+
+int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
+{
+	return kvm_mips_pending_timer(vcpu) ||
+		kvm_read_c0_guest_cause(&vcpu->arch.cop0) & C_TI;
+}
+
+int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu)
+{
+	int i;
+	struct mips_coproc *cop0;
+
+	if (!vcpu)
+		return -1;
+
+	kvm_debug("VCPU Register Dump:\n");
+	kvm_debug("\tpc = 0x%08lx\n", vcpu->arch.pc);
+	kvm_debug("\texceptions: %08lx\n", vcpu->arch.pending_exceptions);
+
+	for (i = 0; i < 32; i += 4) {
+		kvm_debug("\tgpr%02d: %08lx %08lx %08lx %08lx\n", i,
+		       vcpu->arch.gprs[i],
+		       vcpu->arch.gprs[i + 1],
+		       vcpu->arch.gprs[i + 2], vcpu->arch.gprs[i + 3]);
+	}
+	kvm_debug("\thi: 0x%08lx\n", vcpu->arch.hi);
+	kvm_debug("\tlo: 0x%08lx\n", vcpu->arch.lo);
+
+	cop0 = &vcpu->arch.cop0;
+	kvm_debug("\tStatus: 0x%08x, Cause: 0x%08x\n",
+		  kvm_read_c0_guest_status(cop0),
+		  kvm_read_c0_guest_cause(cop0));
+
+	kvm_debug("\tEPC: 0x%08lx\n", kvm_read_c0_guest_epc(cop0));
+
+	return 0;
+}
+
+int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
+{
+	int i;
+
+	vcpu_load(vcpu);
+
+	for (i = 1; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
+		vcpu->arch.gprs[i] = regs->gpr[i];
+	vcpu->arch.gprs[0] = 0; /* zero is special, and cannot be set. */
+	vcpu->arch.hi = regs->hi;
+	vcpu->arch.lo = regs->lo;
+	vcpu->arch.pc = regs->pc;
+
+	vcpu_put(vcpu);
+	return 0;
+}
+
+int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
+{
+	int i;
+
+	vcpu_load(vcpu);
+
+	for (i = 0; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
+		regs->gpr[i] = vcpu->arch.gprs[i];
+
+	regs->hi = vcpu->arch.hi;
+	regs->lo = vcpu->arch.lo;
+	regs->pc = vcpu->arch.pc;
+
+	vcpu_put(vcpu);
+	return 0;
+}
+
+int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
+				  struct kvm_translation *tr)
+{
+	return 0;
+}
+
+static void kvm_mips_set_c0_status(void)
+{
+	u32 status = read_c0_status();
+
+	if (cpu_has_dsp)
+		status |= (ST0_MX);
+
+	write_c0_status(status);
+	ehb();
+}
+
+/*
+ * Return value is in the form (errcode<<2 | RESUME_FLAG_HOST | RESUME_FLAG_NV)
+ */
+static int __kvm_mips_handle_exit(struct kvm_vcpu *vcpu)
+{
+	struct kvm_run *run = vcpu->run;
+	u32 cause = vcpu->arch.host_cp0_cause;
+	u32 exccode = (cause >> CAUSEB_EXCCODE) & 0x1f;
+	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
+	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
+	enum emulation_result er = EMULATE_DONE;
+	u32 inst;
+	int ret = RESUME_GUEST;
+
+	vcpu->mode = OUTSIDE_GUEST_MODE;
+
+	/* Set a default exit reason */
+	run->exit_reason = KVM_EXIT_UNKNOWN;
+	run->ready_for_interrupt_injection = 1;
+
+	/*
+	 * Set the appropriate status bits based on host CPU features,
+	 * before we hit the scheduler
+	 */
+	kvm_mips_set_c0_status();
+
+	local_irq_enable();
+
+	kvm_debug("kvm_mips_handle_exit: cause: %#x, PC: %p, kvm_run: %p, kvm_vcpu: %p\n",
+			cause, opc, run, vcpu);
+	trace_kvm_exit(vcpu, exccode);
+
+	switch (exccode) {
+	case EXCCODE_INT:
+		kvm_debug("[%d]EXCCODE_INT @ %p\n", vcpu->vcpu_id, opc);
+
+		++vcpu->stat.int_exits;
+
+		if (need_resched())
+			cond_resched();
+
+		ret = RESUME_GUEST;
+		break;
+
+	case EXCCODE_CPU:
+		kvm_debug("EXCCODE_CPU: @ PC: %p\n", opc);
+
+		++vcpu->stat.cop_unusable_exits;
+		ret = kvm_mips_callbacks->handle_cop_unusable(vcpu);
+		/* XXXKYMA: Might need to return to user space */
+		if (run->exit_reason == KVM_EXIT_IRQ_WINDOW_OPEN)
+			ret = RESUME_HOST;
+		break;
+
+	case EXCCODE_MOD:
+		++vcpu->stat.tlbmod_exits;
+		ret = kvm_mips_callbacks->handle_tlb_mod(vcpu);
+		break;
+
+	case EXCCODE_TLBS:
+		kvm_debug("TLB ST fault:  cause %#x, status %#x, PC: %p, BadVaddr: %#lx\n",
+			  cause, kvm_read_c0_guest_status(&vcpu->arch.cop0), opc,
+			  badvaddr);
+
+		++vcpu->stat.tlbmiss_st_exits;
+		ret = kvm_mips_callbacks->handle_tlb_st_miss(vcpu);
+		break;
+
+	case EXCCODE_TLBL:
+		kvm_debug("TLB LD fault: cause %#x, PC: %p, BadVaddr: %#lx\n",
+			  cause, opc, badvaddr);
+
+		++vcpu->stat.tlbmiss_ld_exits;
+		ret = kvm_mips_callbacks->handle_tlb_ld_miss(vcpu);
+		break;
+
+	case EXCCODE_ADES:
+		++vcpu->stat.addrerr_st_exits;
+		ret = kvm_mips_callbacks->handle_addr_err_st(vcpu);
+		break;
+
+	case EXCCODE_ADEL:
+		++vcpu->stat.addrerr_ld_exits;
+		ret = kvm_mips_callbacks->handle_addr_err_ld(vcpu);
+		break;
+
+	case EXCCODE_SYS:
+		++vcpu->stat.syscall_exits;
+		ret = kvm_mips_callbacks->handle_syscall(vcpu);
+		break;
+
+	case EXCCODE_RI:
+		++vcpu->stat.resvd_inst_exits;
+		ret = kvm_mips_callbacks->handle_res_inst(vcpu);
+		break;
+
+	case EXCCODE_BP:
+		++vcpu->stat.break_inst_exits;
+		ret = kvm_mips_callbacks->handle_break(vcpu);
+		break;
+
+	case EXCCODE_TR:
+		++vcpu->stat.trap_inst_exits;
+		ret = kvm_mips_callbacks->handle_trap(vcpu);
+		break;
+
+	case EXCCODE_MSAFPE:
+		++vcpu->stat.msa_fpe_exits;
+		ret = kvm_mips_callbacks->handle_msa_fpe(vcpu);
+		break;
+
+	case EXCCODE_FPE:
+		++vcpu->stat.fpe_exits;
+		ret = kvm_mips_callbacks->handle_fpe(vcpu);
+		break;
+
+	case EXCCODE_MSADIS:
+		++vcpu->stat.msa_disabled_exits;
+		ret = kvm_mips_callbacks->handle_msa_disabled(vcpu);
+		break;
+
+	case EXCCODE_GE:
+		/* defer exit accounting to handler */
+		ret = kvm_mips_callbacks->handle_guest_exit(vcpu);
+		break;
+
+	default:
+		if (cause & CAUSEF_BD)
+			opc += 1;
+		inst = 0;
+		kvm_get_badinstr(opc, vcpu, &inst);
+		kvm_err("Exception Code: %d, not yet handled, @ PC: %p, inst: 0x%08x  BadVaddr: %#lx Status: %#x\n",
+			exccode, opc, inst, badvaddr,
+			kvm_read_c0_guest_status(&vcpu->arch.cop0));
+		kvm_arch_vcpu_dump_regs(vcpu);
+		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+		ret = RESUME_HOST;
+		break;
+
+	}
+
+	local_irq_disable();
+
+	if (ret == RESUME_GUEST)
+		kvm_vz_acquire_htimer(vcpu);
+
+	if (er == EMULATE_DONE && !(ret & RESUME_HOST))
+		kvm_mips_deliver_interrupts(vcpu, cause);
+
+	if (!(ret & RESUME_HOST)) {
+		/* Only check for signals if not already exiting to userspace */
+		if (signal_pending(current)) {
+			run->exit_reason = KVM_EXIT_INTR;
+			ret = (-EINTR << 2) | RESUME_HOST;
+			++vcpu->stat.signal_exits;
+			trace_kvm_exit(vcpu, KVM_TRACE_EXIT_SIGNAL);
+		}
+	}
+
+	if (ret == RESUME_GUEST) {
+		trace_kvm_reenter(vcpu);
+
+		/*
+		 * Make sure the read of VCPU requests in vcpu_reenter()
+		 * callback is not reordered ahead of the write to vcpu->mode,
+		 * or we could miss a TLB flush request while the requester sees
+		 * the VCPU as outside of guest mode and not needing an IPI.
+		 */
+		smp_store_mb(vcpu->mode, IN_GUEST_MODE);
+
+		kvm_mips_callbacks->vcpu_reenter(vcpu);
+
+		/*
+		 * If FPU / MSA are enabled (i.e. the guest's FPU / MSA context
+		 * is live), restore FCR31 / MSACSR.
+		 *
+		 * This should be before returning to the guest exception
+		 * vector, as it may well cause an [MSA] FP exception if there
+		 * are pending exception bits unmasked. (see
+		 * kvm_mips_csr_die_notifier() for how that is handled).
+		 */
+		if (kvm_mips_guest_has_fpu(&vcpu->arch) &&
+		    read_c0_status() & ST0_CU1)
+			__kvm_restore_fcsr(&vcpu->arch);
+
+		if (kvm_mips_guest_has_msa(&vcpu->arch) &&
+		    read_c0_config5() & MIPS_CONF5_MSAEN)
+			__kvm_restore_msacsr(&vcpu->arch);
+	}
+	return ret;
+}
+
+int noinstr kvm_mips_handle_exit(struct kvm_vcpu *vcpu)
+{
+	int ret;
+
+	guest_state_exit_irqoff();
+	ret = __kvm_mips_handle_exit(vcpu);
+	guest_state_enter_irqoff();
+
+	return ret;
+}
+
+/* Enable FPU for guest and restore context */
+void kvm_own_fpu(struct kvm_vcpu *vcpu)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+	unsigned int sr, cfg5;
+
+	preempt_disable();
+
+	sr = kvm_read_c0_guest_status(cop0);
+
+	/*
+	 * If MSA state is already live, it is undefined how it interacts with
+	 * FR=0 FPU state, and we don't want to hit reserved instruction
+	 * exceptions trying to save the MSA state later when CU=1 && FR=1, so
+	 * play it safe and save it first.
+	 */
+	if (cpu_has_msa && sr & ST0_CU1 && !(sr & ST0_FR) &&
+	    vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA)
+		kvm_lose_fpu(vcpu);
+
+	/*
+	 * Enable FPU for guest
+	 * We set FR and FRE according to guest context
+	 */
+	change_c0_status(ST0_CU1 | ST0_FR, sr);
+	if (cpu_has_fre) {
+		cfg5 = kvm_read_c0_guest_config5(cop0);
+		change_c0_config5(MIPS_CONF5_FRE, cfg5);
+	}
+	enable_fpu_hazard();
+
+	/* If guest FPU state not active, restore it now */
+	if (!(vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU)) {
+		__kvm_restore_fpu(&vcpu->arch);
+		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
+		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_FPU);
+	} else {
+		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_FPU);
+	}
+
+	preempt_enable();
+}
+
+#ifdef CONFIG_CPU_HAS_MSA
+/* Enable MSA for guest and restore context */
+void kvm_own_msa(struct kvm_vcpu *vcpu)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+	unsigned int sr, cfg5;
+
+	preempt_disable();
+
+	/*
+	 * Enable FPU if enabled in guest, since we're restoring FPU context
+	 * anyway. We set FR and FRE according to guest context.
+	 */
+	if (kvm_mips_guest_has_fpu(&vcpu->arch)) {
+		sr = kvm_read_c0_guest_status(cop0);
+
+		/*
+		 * If FR=0 FPU state is already live, it is undefined how it
+		 * interacts with MSA state, so play it safe and save it first.
+		 */
+		if (!(sr & ST0_FR) &&
+		    (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU |
+				KVM_MIPS_AUX_MSA)) == KVM_MIPS_AUX_FPU)
+			kvm_lose_fpu(vcpu);
+
+		change_c0_status(ST0_CU1 | ST0_FR, sr);
+		if (sr & ST0_CU1 && cpu_has_fre) {
+			cfg5 = kvm_read_c0_guest_config5(cop0);
+			change_c0_config5(MIPS_CONF5_FRE, cfg5);
+		}
+	}
+
+	/* Enable MSA for guest */
+	set_c0_config5(MIPS_CONF5_MSAEN);
+	enable_fpu_hazard();
+
+	switch (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA)) {
+	case KVM_MIPS_AUX_FPU:
+		/*
+		 * Guest FPU state already loaded, only restore upper MSA state
+		 */
+		__kvm_restore_msa_upper(&vcpu->arch);
+		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
+		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_MSA);
+		break;
+	case 0:
+		/* Neither FPU or MSA already active, restore full MSA state */
+		__kvm_restore_msa(&vcpu->arch);
+		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
+		if (kvm_mips_guest_has_fpu(&vcpu->arch))
+			vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
+		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE,
+			      KVM_TRACE_AUX_FPU_MSA);
+		break;
+	default:
+		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_MSA);
+		break;
+	}
+
+	preempt_enable();
+}
+#endif
+
+/* Drop FPU & MSA without saving it */
+void kvm_drop_fpu(struct kvm_vcpu *vcpu)
+{
+	preempt_disable();
+	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
+		disable_msa();
+		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_MSA);
+		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_MSA;
+	}
+	if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
+		clear_c0_status(ST0_CU1 | ST0_FR);
+		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_FPU);
+		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
+	}
+	preempt_enable();
+}
+
+/* Save and disable FPU & MSA */
+void kvm_lose_fpu(struct kvm_vcpu *vcpu)
+{
+	/*
+	 * With T&E, FPU & MSA get disabled in root context (hardware) when it
+	 * is disabled in guest context (software), but the register state in
+	 * the hardware may still be in use.
+	 * This is why we explicitly re-enable the hardware before saving.
+	 */
+
+	preempt_disable();
+	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
+		__kvm_save_msa(&vcpu->arch);
+		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU_MSA);
+
+		/* Disable MSA & FPU */
+		disable_msa();
+		if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
+			clear_c0_status(ST0_CU1 | ST0_FR);
+			disable_fpu_hazard();
+		}
+		vcpu->arch.aux_inuse &= ~(KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA);
+	} else if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
+		__kvm_save_fpu(&vcpu->arch);
+		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
+		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU);
+
+		/* Disable FPU */
+		clear_c0_status(ST0_CU1 | ST0_FR);
+		disable_fpu_hazard();
+	}
+	preempt_enable();
+}
+
+/*
+ * Step over a specific ctc1 to FCSR and a specific ctcmsa to MSACSR which are
+ * used to restore guest FCSR/MSACSR state and may trigger a "harmless" FP/MSAFP
+ * exception if cause bits are set in the value being written.
+ */
+static int kvm_mips_csr_die_notify(struct notifier_block *self,
+				   unsigned long cmd, void *ptr)
+{
+	struct die_args *args = (struct die_args *)ptr;
+	struct pt_regs *regs = args->regs;
+	unsigned long pc;
+
+	/* Only interested in FPE and MSAFPE */
+	if (cmd != DIE_FP && cmd != DIE_MSAFP)
+		return NOTIFY_DONE;
+
+	/* Return immediately if guest context isn't active */
+	if (!(current->flags & PF_VCPU))
+		return NOTIFY_DONE;
+
+	/* Should never get here from user mode */
+	BUG_ON(user_mode(regs));
+
+	pc = instruction_pointer(regs);
+	switch (cmd) {
+	case DIE_FP:
+		/* match 2nd instruction in __kvm_restore_fcsr */
+		if (pc != (unsigned long)&__kvm_restore_fcsr + 4)
+			return NOTIFY_DONE;
+		break;
+	case DIE_MSAFP:
+		/* match 2nd/3rd instruction in __kvm_restore_msacsr */
+		if (!cpu_has_msa ||
+		    pc < (unsigned long)&__kvm_restore_msacsr + 4 ||
+		    pc > (unsigned long)&__kvm_restore_msacsr + 8)
+			return NOTIFY_DONE;
+		break;
+	}
+
+	/* Move PC forward a little and continue executing */
+	instruction_pointer(regs) += 4;
+
+	return NOTIFY_STOP;
+}
+
+static struct notifier_block kvm_mips_csr_die_notifier = {
+	.notifier_call = kvm_mips_csr_die_notify,
+};
+
+static u32 kvm_default_priority_to_irq[MIPS_EXC_MAX] = {
+	[MIPS_EXC_INT_TIMER] = C_IRQ5,
+	[MIPS_EXC_INT_IO_1]  = C_IRQ0,
+	[MIPS_EXC_INT_IPI_1] = C_IRQ1,
+	[MIPS_EXC_INT_IPI_2] = C_IRQ2,
+};
+
+static u32 kvm_loongson3_priority_to_irq[MIPS_EXC_MAX] = {
+	[MIPS_EXC_INT_TIMER] = C_IRQ5,
+	[MIPS_EXC_INT_IO_1]  = C_IRQ0,
+	[MIPS_EXC_INT_IO_2]  = C_IRQ1,
+	[MIPS_EXC_INT_IPI_1] = C_IRQ4,
+};
+
+u32 *kvm_priority_to_irq = kvm_default_priority_to_irq;
+
+u32 kvm_irq_to_priority(u32 irq)
+{
+	int i;
+
+	for (i = MIPS_EXC_INT_TIMER; i < MIPS_EXC_MAX; i++) {
+		if (kvm_priority_to_irq[i] == (1 << (irq + 8)))
+			return i;
+	}
+
+	return MIPS_EXC_MAX;
+}
+
+static int __init kvm_mips_init(void)
+{
+	int ret;
+
+	if (cpu_has_mmid) {
+		pr_warn("KVM does not yet support MMIDs. KVM Disabled\n");
+		return -EOPNOTSUPP;
+	}
+
+	ret = kvm_mips_entry_setup();
+	if (ret)
+		return ret;
+
+	ret = kvm_mips_emulation_init();
+	if (ret)
+		return ret;
+
+
+	if (boot_cpu_type() == CPU_LOONGSON64)
+		kvm_priority_to_irq = kvm_loongson3_priority_to_irq;
+
+	register_die_notifier(&kvm_mips_csr_die_notifier);
+
+	ret = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
+	if (ret) {
+		unregister_die_notifier(&kvm_mips_csr_die_notifier);
+		return ret;
+	}
+	return 0;
+}
+
+static void __exit kvm_mips_exit(void)
+{
+	kvm_exit();
+
+	unregister_die_notifier(&kvm_mips_csr_die_notifier);
+}
+
+module_init(kvm_mips_init);
+module_exit(kvm_mips_exit);
+
+EXPORT_TRACEPOINT_SYMBOL(kvm_exit);
diff --git a/arch/mips/kvm/mmu.c b/arch/mips/kvm/mmu.c
new file mode 100644
index 000000000..467ee6b95
--- /dev/null
+++ b/arch/mips/kvm/mmu.c
@@ -0,0 +1,757 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * KVM/MIPS MMU handling in the KVM module.
+ *
+ * Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.
+ * Authors: Sanjay Lal <sanjayl@kymasys.com>
+ */
+
+#include <linux/highmem.h>
+#include <linux/kvm_host.h>
+#include <linux/uaccess.h>
+#include <asm/mmu_context.h>
+#include <asm/pgalloc.h>
+
+/*
+ * KVM_MMU_CACHE_MIN_PAGES is the number of GPA page table translation levels
+ * for which pages need to be cached.
+ */
+#if defined(__PAGETABLE_PMD_FOLDED)
+#define KVM_MMU_CACHE_MIN_PAGES 1
+#else
+#define KVM_MMU_CACHE_MIN_PAGES 2
+#endif
+
+void kvm_mmu_free_memory_caches(struct kvm_vcpu *vcpu)
+{
+	kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
+}
+
+/**
+ * kvm_pgd_init() - Initialise KVM GPA page directory.
+ * @page:	Pointer to page directory (PGD) for KVM GPA.
+ *
+ * Initialise a KVM GPA page directory with pointers to the invalid table, i.e.
+ * representing no mappings. This is similar to pgd_init(), however it
+ * initialises all the page directory pointers, not just the ones corresponding
+ * to the userland address space (since it is for the guest physical address
+ * space rather than a virtual address space).
+ */
+static void kvm_pgd_init(void *page)
+{
+	unsigned long *p, *end;
+	unsigned long entry;
+
+#ifdef __PAGETABLE_PMD_FOLDED
+	entry = (unsigned long)invalid_pte_table;
+#else
+	entry = (unsigned long)invalid_pmd_table;
+#endif
+
+	p = (unsigned long *)page;
+	end = p + PTRS_PER_PGD;
+
+	do {
+		p[0] = entry;
+		p[1] = entry;
+		p[2] = entry;
+		p[3] = entry;
+		p[4] = entry;
+		p += 8;
+		p[-3] = entry;
+		p[-2] = entry;
+		p[-1] = entry;
+	} while (p != end);
+}
+
+/**
+ * kvm_pgd_alloc() - Allocate and initialise a KVM GPA page directory.
+ *
+ * Allocate a blank KVM GPA page directory (PGD) for representing guest physical
+ * to host physical page mappings.
+ *
+ * Returns:	Pointer to new KVM GPA page directory.
+ *		NULL on allocation failure.
+ */
+pgd_t *kvm_pgd_alloc(void)
+{
+	pgd_t *ret;
+
+	ret = (pgd_t *)__get_free_pages(GFP_KERNEL, PGD_TABLE_ORDER);
+	if (ret)
+		kvm_pgd_init(ret);
+
+	return ret;
+}
+
+/**
+ * kvm_mips_walk_pgd() - Walk page table with optional allocation.
+ * @pgd:	Page directory pointer.
+ * @addr:	Address to index page table using.
+ * @cache:	MMU page cache to allocate new page tables from, or NULL.
+ *
+ * Walk the page tables pointed to by @pgd to find the PTE corresponding to the
+ * address @addr. If page tables don't exist for @addr, they will be created
+ * from the MMU cache if @cache is not NULL.
+ *
+ * Returns:	Pointer to pte_t corresponding to @addr.
+ *		NULL if a page table doesn't exist for @addr and !@cache.
+ *		NULL if a page table allocation failed.
+ */
+static pte_t *kvm_mips_walk_pgd(pgd_t *pgd, struct kvm_mmu_memory_cache *cache,
+				unsigned long addr)
+{
+	p4d_t *p4d;
+	pud_t *pud;
+	pmd_t *pmd;
+
+	pgd += pgd_index(addr);
+	if (pgd_none(*pgd)) {
+		/* Not used on MIPS yet */
+		BUG();
+		return NULL;
+	}
+	p4d = p4d_offset(pgd, addr);
+	pud = pud_offset(p4d, addr);
+	if (pud_none(*pud)) {
+		pmd_t *new_pmd;
+
+		if (!cache)
+			return NULL;
+		new_pmd = kvm_mmu_memory_cache_alloc(cache);
+		pmd_init(new_pmd);
+		pud_populate(NULL, pud, new_pmd);
+	}
+	pmd = pmd_offset(pud, addr);
+	if (pmd_none(*pmd)) {
+		pte_t *new_pte;
+
+		if (!cache)
+			return NULL;
+		new_pte = kvm_mmu_memory_cache_alloc(cache);
+		clear_page(new_pte);
+		pmd_populate_kernel(NULL, pmd, new_pte);
+	}
+	return pte_offset_kernel(pmd, addr);
+}
+
+/* Caller must hold kvm->mm_lock */
+static pte_t *kvm_mips_pte_for_gpa(struct kvm *kvm,
+				   struct kvm_mmu_memory_cache *cache,
+				   unsigned long addr)
+{
+	return kvm_mips_walk_pgd(kvm->arch.gpa_mm.pgd, cache, addr);
+}
+
+/*
+ * kvm_mips_flush_gpa_{pte,pmd,pud,pgd,pt}.
+ * Flush a range of guest physical address space from the VM's GPA page tables.
+ */
+
+static bool kvm_mips_flush_gpa_pte(pte_t *pte, unsigned long start_gpa,
+				   unsigned long end_gpa)
+{
+	int i_min = pte_index(start_gpa);
+	int i_max = pte_index(end_gpa);
+	bool safe_to_remove = (i_min == 0 && i_max == PTRS_PER_PTE - 1);
+	int i;
+
+	for (i = i_min; i <= i_max; ++i) {
+		if (!pte_present(pte[i]))
+			continue;
+
+		set_pte(pte + i, __pte(0));
+	}
+	return safe_to_remove;
+}
+
+static bool kvm_mips_flush_gpa_pmd(pmd_t *pmd, unsigned long start_gpa,
+				   unsigned long end_gpa)
+{
+	pte_t *pte;
+	unsigned long end = ~0ul;
+	int i_min = pmd_index(start_gpa);
+	int i_max = pmd_index(end_gpa);
+	bool safe_to_remove = (i_min == 0 && i_max == PTRS_PER_PMD - 1);
+	int i;
+
+	for (i = i_min; i <= i_max; ++i, start_gpa = 0) {
+		if (!pmd_present(pmd[i]))
+			continue;
+
+		pte = pte_offset_kernel(pmd + i, 0);
+		if (i == i_max)
+			end = end_gpa;
+
+		if (kvm_mips_flush_gpa_pte(pte, start_gpa, end)) {
+			pmd_clear(pmd + i);
+			pte_free_kernel(NULL, pte);
+		} else {
+			safe_to_remove = false;
+		}
+	}
+	return safe_to_remove;
+}
+
+static bool kvm_mips_flush_gpa_pud(pud_t *pud, unsigned long start_gpa,
+				   unsigned long end_gpa)
+{
+	pmd_t *pmd;
+	unsigned long end = ~0ul;
+	int i_min = pud_index(start_gpa);
+	int i_max = pud_index(end_gpa);
+	bool safe_to_remove = (i_min == 0 && i_max == PTRS_PER_PUD - 1);
+	int i;
+
+	for (i = i_min; i <= i_max; ++i, start_gpa = 0) {
+		if (!pud_present(pud[i]))
+			continue;
+
+		pmd = pmd_offset(pud + i, 0);
+		if (i == i_max)
+			end = end_gpa;
+
+		if (kvm_mips_flush_gpa_pmd(pmd, start_gpa, end)) {
+			pud_clear(pud + i);
+			pmd_free(NULL, pmd);
+		} else {
+			safe_to_remove = false;
+		}
+	}
+	return safe_to_remove;
+}
+
+static bool kvm_mips_flush_gpa_pgd(pgd_t *pgd, unsigned long start_gpa,
+				   unsigned long end_gpa)
+{
+	p4d_t *p4d;
+	pud_t *pud;
+	unsigned long end = ~0ul;
+	int i_min = pgd_index(start_gpa);
+	int i_max = pgd_index(end_gpa);
+	bool safe_to_remove = (i_min == 0 && i_max == PTRS_PER_PGD - 1);
+	int i;
+
+	for (i = i_min; i <= i_max; ++i, start_gpa = 0) {
+		if (!pgd_present(pgd[i]))
+			continue;
+
+		p4d = p4d_offset(pgd, 0);
+		pud = pud_offset(p4d + i, 0);
+		if (i == i_max)
+			end = end_gpa;
+
+		if (kvm_mips_flush_gpa_pud(pud, start_gpa, end)) {
+			pgd_clear(pgd + i);
+			pud_free(NULL, pud);
+		} else {
+			safe_to_remove = false;
+		}
+	}
+	return safe_to_remove;
+}
+
+/**
+ * kvm_mips_flush_gpa_pt() - Flush a range of guest physical addresses.
+ * @kvm:	KVM pointer.
+ * @start_gfn:	Guest frame number of first page in GPA range to flush.
+ * @end_gfn:	Guest frame number of last page in GPA range to flush.
+ *
+ * Flushes a range of GPA mappings from the GPA page tables.
+ *
+ * The caller must hold the @kvm->mmu_lock spinlock.
+ *
+ * Returns:	Whether its safe to remove the top level page directory because
+ *		all lower levels have been removed.
+ */
+bool kvm_mips_flush_gpa_pt(struct kvm *kvm, gfn_t start_gfn, gfn_t end_gfn)
+{
+	return kvm_mips_flush_gpa_pgd(kvm->arch.gpa_mm.pgd,
+				      start_gfn << PAGE_SHIFT,
+				      end_gfn << PAGE_SHIFT);
+}
+
+#define BUILD_PTE_RANGE_OP(name, op)					\
+static int kvm_mips_##name##_pte(pte_t *pte, unsigned long start,	\
+				 unsigned long end)			\
+{									\
+	int ret = 0;							\
+	int i_min = pte_index(start);				\
+	int i_max = pte_index(end);					\
+	int i;								\
+	pte_t old, new;							\
+									\
+	for (i = i_min; i <= i_max; ++i) {				\
+		if (!pte_present(pte[i]))				\
+			continue;					\
+									\
+		old = pte[i];						\
+		new = op(old);						\
+		if (pte_val(new) == pte_val(old))			\
+			continue;					\
+		set_pte(pte + i, new);					\
+		ret = 1;						\
+	}								\
+	return ret;							\
+}									\
+									\
+/* returns true if anything was done */					\
+static int kvm_mips_##name##_pmd(pmd_t *pmd, unsigned long start,	\
+				 unsigned long end)			\
+{									\
+	int ret = 0;							\
+	pte_t *pte;							\
+	unsigned long cur_end = ~0ul;					\
+	int i_min = pmd_index(start);				\
+	int i_max = pmd_index(end);					\
+	int i;								\
+									\
+	for (i = i_min; i <= i_max; ++i, start = 0) {			\
+		if (!pmd_present(pmd[i]))				\
+			continue;					\
+									\
+		pte = pte_offset_kernel(pmd + i, 0);				\
+		if (i == i_max)						\
+			cur_end = end;					\
+									\
+		ret |= kvm_mips_##name##_pte(pte, start, cur_end);	\
+	}								\
+	return ret;							\
+}									\
+									\
+static int kvm_mips_##name##_pud(pud_t *pud, unsigned long start,	\
+				 unsigned long end)			\
+{									\
+	int ret = 0;							\
+	pmd_t *pmd;							\
+	unsigned long cur_end = ~0ul;					\
+	int i_min = pud_index(start);				\
+	int i_max = pud_index(end);					\
+	int i;								\
+									\
+	for (i = i_min; i <= i_max; ++i, start = 0) {			\
+		if (!pud_present(pud[i]))				\
+			continue;					\
+									\
+		pmd = pmd_offset(pud + i, 0);				\
+		if (i == i_max)						\
+			cur_end = end;					\
+									\
+		ret |= kvm_mips_##name##_pmd(pmd, start, cur_end);	\
+	}								\
+	return ret;							\
+}									\
+									\
+static int kvm_mips_##name##_pgd(pgd_t *pgd, unsigned long start,	\
+				 unsigned long end)			\
+{									\
+	int ret = 0;							\
+	p4d_t *p4d;							\
+	pud_t *pud;							\
+	unsigned long cur_end = ~0ul;					\
+	int i_min = pgd_index(start);					\
+	int i_max = pgd_index(end);					\
+	int i;								\
+									\
+	for (i = i_min; i <= i_max; ++i, start = 0) {			\
+		if (!pgd_present(pgd[i]))				\
+			continue;					\
+									\
+		p4d = p4d_offset(pgd, 0);				\
+		pud = pud_offset(p4d + i, 0);				\
+		if (i == i_max)						\
+			cur_end = end;					\
+									\
+		ret |= kvm_mips_##name##_pud(pud, start, cur_end);	\
+	}								\
+	return ret;							\
+}
+
+/*
+ * kvm_mips_mkclean_gpa_pt.
+ * Mark a range of guest physical address space clean (writes fault) in the VM's
+ * GPA page table to allow dirty page tracking.
+ */
+
+BUILD_PTE_RANGE_OP(mkclean, pte_mkclean)
+
+/**
+ * kvm_mips_mkclean_gpa_pt() - Make a range of guest physical addresses clean.
+ * @kvm:	KVM pointer.
+ * @start_gfn:	Guest frame number of first page in GPA range to flush.
+ * @end_gfn:	Guest frame number of last page in GPA range to flush.
+ *
+ * Make a range of GPA mappings clean so that guest writes will fault and
+ * trigger dirty page logging.
+ *
+ * The caller must hold the @kvm->mmu_lock spinlock.
+ *
+ * Returns:	Whether any GPA mappings were modified, which would require
+ *		derived mappings (GVA page tables & TLB enties) to be
+ *		invalidated.
+ */
+int kvm_mips_mkclean_gpa_pt(struct kvm *kvm, gfn_t start_gfn, gfn_t end_gfn)
+{
+	return kvm_mips_mkclean_pgd(kvm->arch.gpa_mm.pgd,
+				    start_gfn << PAGE_SHIFT,
+				    end_gfn << PAGE_SHIFT);
+}
+
+/**
+ * kvm_arch_mmu_enable_log_dirty_pt_masked() - write protect dirty pages
+ * @kvm:	The KVM pointer
+ * @slot:	The memory slot associated with mask
+ * @gfn_offset:	The gfn offset in memory slot
+ * @mask:	The mask of dirty pages at offset 'gfn_offset' in this memory
+ *		slot to be write protected
+ *
+ * Walks bits set in mask write protects the associated pte's. Caller must
+ * acquire @kvm->mmu_lock.
+ */
+void kvm_arch_mmu_enable_log_dirty_pt_masked(struct kvm *kvm,
+		struct kvm_memory_slot *slot,
+		gfn_t gfn_offset, unsigned long mask)
+{
+	gfn_t base_gfn = slot->base_gfn + gfn_offset;
+	gfn_t start = base_gfn +  __ffs(mask);
+	gfn_t end = base_gfn + __fls(mask);
+
+	kvm_mips_mkclean_gpa_pt(kvm, start, end);
+}
+
+/*
+ * kvm_mips_mkold_gpa_pt.
+ * Mark a range of guest physical address space old (all accesses fault) in the
+ * VM's GPA page table to allow detection of commonly used pages.
+ */
+
+BUILD_PTE_RANGE_OP(mkold, pte_mkold)
+
+static int kvm_mips_mkold_gpa_pt(struct kvm *kvm, gfn_t start_gfn,
+				 gfn_t end_gfn)
+{
+	return kvm_mips_mkold_pgd(kvm->arch.gpa_mm.pgd,
+				  start_gfn << PAGE_SHIFT,
+				  end_gfn << PAGE_SHIFT);
+}
+
+bool kvm_unmap_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range)
+{
+	kvm_mips_flush_gpa_pt(kvm, range->start, range->end);
+	return true;
+}
+
+bool kvm_set_spte_gfn(struct kvm *kvm, struct kvm_gfn_range *range)
+{
+	gpa_t gpa = range->start << PAGE_SHIFT;
+	pte_t hva_pte = range->arg.pte;
+	pte_t *gpa_pte = kvm_mips_pte_for_gpa(kvm, NULL, gpa);
+	pte_t old_pte;
+
+	if (!gpa_pte)
+		return false;
+
+	/* Mapping may need adjusting depending on memslot flags */
+	old_pte = *gpa_pte;
+	if (range->slot->flags & KVM_MEM_LOG_DIRTY_PAGES && !pte_dirty(old_pte))
+		hva_pte = pte_mkclean(hva_pte);
+	else if (range->slot->flags & KVM_MEM_READONLY)
+		hva_pte = pte_wrprotect(hva_pte);
+
+	set_pte(gpa_pte, hva_pte);
+
+	/* Replacing an absent or old page doesn't need flushes */
+	if (!pte_present(old_pte) || !pte_young(old_pte))
+		return false;
+
+	/* Pages swapped, aged, moved, or cleaned require flushes */
+	return !pte_present(hva_pte) ||
+	       !pte_young(hva_pte) ||
+	       pte_pfn(old_pte) != pte_pfn(hva_pte) ||
+	       (pte_dirty(old_pte) && !pte_dirty(hva_pte));
+}
+
+bool kvm_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range)
+{
+	return kvm_mips_mkold_gpa_pt(kvm, range->start, range->end);
+}
+
+bool kvm_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range)
+{
+	gpa_t gpa = range->start << PAGE_SHIFT;
+	pte_t *gpa_pte = kvm_mips_pte_for_gpa(kvm, NULL, gpa);
+
+	if (!gpa_pte)
+		return false;
+	return pte_young(*gpa_pte);
+}
+
+/**
+ * _kvm_mips_map_page_fast() - Fast path GPA fault handler.
+ * @vcpu:		VCPU pointer.
+ * @gpa:		Guest physical address of fault.
+ * @write_fault:	Whether the fault was due to a write.
+ * @out_entry:		New PTE for @gpa (written on success unless NULL).
+ * @out_buddy:		New PTE for @gpa's buddy (written on success unless
+ *			NULL).
+ *
+ * Perform fast path GPA fault handling, doing all that can be done without
+ * calling into KVM. This handles marking old pages young (for idle page
+ * tracking), and dirtying of clean pages (for dirty page logging).
+ *
+ * Returns:	0 on success, in which case we can update derived mappings and
+ *		resume guest execution.
+ *		-EFAULT on failure due to absent GPA mapping or write to
+ *		read-only page, in which case KVM must be consulted.
+ */
+static int _kvm_mips_map_page_fast(struct kvm_vcpu *vcpu, unsigned long gpa,
+				   bool write_fault,
+				   pte_t *out_entry, pte_t *out_buddy)
+{
+	struct kvm *kvm = vcpu->kvm;
+	gfn_t gfn = gpa >> PAGE_SHIFT;
+	pte_t *ptep;
+	kvm_pfn_t pfn = 0;	/* silence bogus GCC warning */
+	bool pfn_valid = false;
+	int ret = 0;
+
+	spin_lock(&kvm->mmu_lock);
+
+	/* Fast path - just check GPA page table for an existing entry */
+	ptep = kvm_mips_pte_for_gpa(kvm, NULL, gpa);
+	if (!ptep || !pte_present(*ptep)) {
+		ret = -EFAULT;
+		goto out;
+	}
+
+	/* Track access to pages marked old */
+	if (!pte_young(*ptep)) {
+		set_pte(ptep, pte_mkyoung(*ptep));
+		pfn = pte_pfn(*ptep);
+		pfn_valid = true;
+		/* call kvm_set_pfn_accessed() after unlock */
+	}
+	if (write_fault && !pte_dirty(*ptep)) {
+		if (!pte_write(*ptep)) {
+			ret = -EFAULT;
+			goto out;
+		}
+
+		/* Track dirtying of writeable pages */
+		set_pte(ptep, pte_mkdirty(*ptep));
+		pfn = pte_pfn(*ptep);
+		mark_page_dirty(kvm, gfn);
+		kvm_set_pfn_dirty(pfn);
+	}
+
+	if (out_entry)
+		*out_entry = *ptep;
+	if (out_buddy)
+		*out_buddy = *ptep_buddy(ptep);
+
+out:
+	spin_unlock(&kvm->mmu_lock);
+	if (pfn_valid)
+		kvm_set_pfn_accessed(pfn);
+	return ret;
+}
+
+/**
+ * kvm_mips_map_page() - Map a guest physical page.
+ * @vcpu:		VCPU pointer.
+ * @gpa:		Guest physical address of fault.
+ * @write_fault:	Whether the fault was due to a write.
+ * @out_entry:		New PTE for @gpa (written on success unless NULL).
+ * @out_buddy:		New PTE for @gpa's buddy (written on success unless
+ *			NULL).
+ *
+ * Handle GPA faults by creating a new GPA mapping (or updating an existing
+ * one).
+ *
+ * This takes care of marking pages young or dirty (idle/dirty page tracking),
+ * asking KVM for the corresponding PFN, and creating a mapping in the GPA page
+ * tables. Derived mappings (GVA page tables and TLBs) must be handled by the
+ * caller.
+ *
+ * Returns:	0 on success, in which case the caller may use the @out_entry
+ *		and @out_buddy PTEs to update derived mappings and resume guest
+ *		execution.
+ *		-EFAULT if there is no memory region at @gpa or a write was
+ *		attempted to a read-only memory region. This is usually handled
+ *		as an MMIO access.
+ */
+static int kvm_mips_map_page(struct kvm_vcpu *vcpu, unsigned long gpa,
+			     bool write_fault,
+			     pte_t *out_entry, pte_t *out_buddy)
+{
+	struct kvm *kvm = vcpu->kvm;
+	struct kvm_mmu_memory_cache *memcache = &vcpu->arch.mmu_page_cache;
+	gfn_t gfn = gpa >> PAGE_SHIFT;
+	int srcu_idx, err;
+	kvm_pfn_t pfn;
+	pte_t *ptep, entry;
+	bool writeable;
+	unsigned long prot_bits;
+	unsigned long mmu_seq;
+
+	/* Try the fast path to handle old / clean pages */
+	srcu_idx = srcu_read_lock(&kvm->srcu);
+	err = _kvm_mips_map_page_fast(vcpu, gpa, write_fault, out_entry,
+				      out_buddy);
+	if (!err)
+		goto out;
+
+	/* We need a minimum of cached pages ready for page table creation */
+	err = kvm_mmu_topup_memory_cache(memcache, KVM_MMU_CACHE_MIN_PAGES);
+	if (err)
+		goto out;
+
+retry:
+	/*
+	 * Used to check for invalidations in progress, of the pfn that is
+	 * returned by pfn_to_pfn_prot below.
+	 */
+	mmu_seq = kvm->mmu_invalidate_seq;
+	/*
+	 * Ensure the read of mmu_invalidate_seq isn't reordered with PTE reads
+	 * in gfn_to_pfn_prot() (which calls get_user_pages()), so that we don't
+	 * risk the page we get a reference to getting unmapped before we have a
+	 * chance to grab the mmu_lock without mmu_invalidate_retry() noticing.
+	 *
+	 * This smp_rmb() pairs with the effective smp_wmb() of the combination
+	 * of the pte_unmap_unlock() after the PTE is zapped, and the
+	 * spin_lock() in kvm_mmu_notifier_invalidate_<page|range_end>() before
+	 * mmu_invalidate_seq is incremented.
+	 */
+	smp_rmb();
+
+	/* Slow path - ask KVM core whether we can access this GPA */
+	pfn = gfn_to_pfn_prot(kvm, gfn, write_fault, &writeable);
+	if (is_error_noslot_pfn(pfn)) {
+		err = -EFAULT;
+		goto out;
+	}
+
+	spin_lock(&kvm->mmu_lock);
+	/* Check if an invalidation has taken place since we got pfn */
+	if (mmu_invalidate_retry(kvm, mmu_seq)) {
+		/*
+		 * This can happen when mappings are changed asynchronously, but
+		 * also synchronously if a COW is triggered by
+		 * gfn_to_pfn_prot().
+		 */
+		spin_unlock(&kvm->mmu_lock);
+		kvm_release_pfn_clean(pfn);
+		goto retry;
+	}
+
+	/* Ensure page tables are allocated */
+	ptep = kvm_mips_pte_for_gpa(kvm, memcache, gpa);
+
+	/* Set up the PTE */
+	prot_bits = _PAGE_PRESENT | __READABLE | _page_cachable_default;
+	if (writeable) {
+		prot_bits |= _PAGE_WRITE;
+		if (write_fault) {
+			prot_bits |= __WRITEABLE;
+			mark_page_dirty(kvm, gfn);
+			kvm_set_pfn_dirty(pfn);
+		}
+	}
+	entry = pfn_pte(pfn, __pgprot(prot_bits));
+
+	/* Write the PTE */
+	set_pte(ptep, entry);
+
+	err = 0;
+	if (out_entry)
+		*out_entry = *ptep;
+	if (out_buddy)
+		*out_buddy = *ptep_buddy(ptep);
+
+	spin_unlock(&kvm->mmu_lock);
+	kvm_release_pfn_clean(pfn);
+	kvm_set_pfn_accessed(pfn);
+out:
+	srcu_read_unlock(&kvm->srcu, srcu_idx);
+	return err;
+}
+
+int kvm_mips_handle_vz_root_tlb_fault(unsigned long badvaddr,
+				      struct kvm_vcpu *vcpu,
+				      bool write_fault)
+{
+	int ret;
+
+	ret = kvm_mips_map_page(vcpu, badvaddr, write_fault, NULL, NULL);
+	if (ret)
+		return ret;
+
+	/* Invalidate this entry in the TLB */
+	return kvm_vz_host_tlb_inv(vcpu, badvaddr);
+}
+
+/**
+ * kvm_mips_migrate_count() - Migrate timer.
+ * @vcpu:	Virtual CPU.
+ *
+ * Migrate CP0_Count hrtimer to the current CPU by cancelling and restarting it
+ * if it was running prior to being cancelled.
+ *
+ * Must be called when the VCPU is migrated to a different CPU to ensure that
+ * timer expiry during guest execution interrupts the guest and causes the
+ * interrupt to be delivered in a timely manner.
+ */
+static void kvm_mips_migrate_count(struct kvm_vcpu *vcpu)
+{
+	if (hrtimer_cancel(&vcpu->arch.comparecount_timer))
+		hrtimer_restart(&vcpu->arch.comparecount_timer);
+}
+
+/* Restore ASID once we are scheduled back after preemption */
+void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
+{
+	unsigned long flags;
+
+	kvm_debug("%s: vcpu %p, cpu: %d\n", __func__, vcpu, cpu);
+
+	local_irq_save(flags);
+
+	vcpu->cpu = cpu;
+	if (vcpu->arch.last_sched_cpu != cpu) {
+		kvm_debug("[%d->%d]KVM VCPU[%d] switch\n",
+			  vcpu->arch.last_sched_cpu, cpu, vcpu->vcpu_id);
+		/*
+		 * Migrate the timer interrupt to the current CPU so that it
+		 * always interrupts the guest and synchronously triggers a
+		 * guest timer interrupt.
+		 */
+		kvm_mips_migrate_count(vcpu);
+	}
+
+	/* restore guest state to registers */
+	kvm_mips_callbacks->vcpu_load(vcpu, cpu);
+
+	local_irq_restore(flags);
+}
+
+/* ASID can change if another task is scheduled during preemption */
+void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
+{
+	unsigned long flags;
+	int cpu;
+
+	local_irq_save(flags);
+
+	cpu = smp_processor_id();
+	vcpu->arch.last_sched_cpu = cpu;
+	vcpu->cpu = -1;
+
+	/* save guest state in registers */
+	kvm_mips_callbacks->vcpu_put(vcpu, cpu);
+
+	local_irq_restore(flags);
+}
diff --git a/arch/mips/kvm/msa.S b/arch/mips/kvm/msa.S
new file mode 100644
index 000000000..d02f0c6cc
--- /dev/null
+++ b/arch/mips/kvm/msa.S
@@ -0,0 +1,161 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * MIPS SIMD Architecture (MSA) context handling code for KVM.
+ *
+ * Copyright (C) 2015 Imagination Technologies Ltd.
+ */
+
+#include <asm/asm.h>
+#include <asm/asm-offsets.h>
+#include <asm/asmmacro.h>
+#include <asm/regdef.h>
+
+	.set	noreorder
+	.set	noat
+
+LEAF(__kvm_save_msa)
+	st_d	0,  VCPU_FPR0,  a0
+	st_d	1,  VCPU_FPR1,  a0
+	st_d	2,  VCPU_FPR2,  a0
+	st_d	3,  VCPU_FPR3,  a0
+	st_d	4,  VCPU_FPR4,  a0
+	st_d	5,  VCPU_FPR5,  a0
+	st_d	6,  VCPU_FPR6,  a0
+	st_d	7,  VCPU_FPR7,  a0
+	st_d	8,  VCPU_FPR8,  a0
+	st_d	9,  VCPU_FPR9,  a0
+	st_d	10, VCPU_FPR10, a0
+	st_d	11, VCPU_FPR11, a0
+	st_d	12, VCPU_FPR12, a0
+	st_d	13, VCPU_FPR13, a0
+	st_d	14, VCPU_FPR14, a0
+	st_d	15, VCPU_FPR15, a0
+	st_d	16, VCPU_FPR16, a0
+	st_d	17, VCPU_FPR17, a0
+	st_d	18, VCPU_FPR18, a0
+	st_d	19, VCPU_FPR19, a0
+	st_d	20, VCPU_FPR20, a0
+	st_d	21, VCPU_FPR21, a0
+	st_d	22, VCPU_FPR22, a0
+	st_d	23, VCPU_FPR23, a0
+	st_d	24, VCPU_FPR24, a0
+	st_d	25, VCPU_FPR25, a0
+	st_d	26, VCPU_FPR26, a0
+	st_d	27, VCPU_FPR27, a0
+	st_d	28, VCPU_FPR28, a0
+	st_d	29, VCPU_FPR29, a0
+	st_d	30, VCPU_FPR30, a0
+	st_d	31, VCPU_FPR31, a0
+	jr	ra
+	 nop
+	END(__kvm_save_msa)
+
+LEAF(__kvm_restore_msa)
+	ld_d	0,  VCPU_FPR0,  a0
+	ld_d	1,  VCPU_FPR1,  a0
+	ld_d	2,  VCPU_FPR2,  a0
+	ld_d	3,  VCPU_FPR3,  a0
+	ld_d	4,  VCPU_FPR4,  a0
+	ld_d	5,  VCPU_FPR5,  a0
+	ld_d	6,  VCPU_FPR6,  a0
+	ld_d	7,  VCPU_FPR7,  a0
+	ld_d	8,  VCPU_FPR8,  a0
+	ld_d	9,  VCPU_FPR9,  a0
+	ld_d	10, VCPU_FPR10, a0
+	ld_d	11, VCPU_FPR11, a0
+	ld_d	12, VCPU_FPR12, a0
+	ld_d	13, VCPU_FPR13, a0
+	ld_d	14, VCPU_FPR14, a0
+	ld_d	15, VCPU_FPR15, a0
+	ld_d	16, VCPU_FPR16, a0
+	ld_d	17, VCPU_FPR17, a0
+	ld_d	18, VCPU_FPR18, a0
+	ld_d	19, VCPU_FPR19, a0
+	ld_d	20, VCPU_FPR20, a0
+	ld_d	21, VCPU_FPR21, a0
+	ld_d	22, VCPU_FPR22, a0
+	ld_d	23, VCPU_FPR23, a0
+	ld_d	24, VCPU_FPR24, a0
+	ld_d	25, VCPU_FPR25, a0
+	ld_d	26, VCPU_FPR26, a0
+	ld_d	27, VCPU_FPR27, a0
+	ld_d	28, VCPU_FPR28, a0
+	ld_d	29, VCPU_FPR29, a0
+	ld_d	30, VCPU_FPR30, a0
+	ld_d	31, VCPU_FPR31, a0
+	jr	ra
+	 nop
+	END(__kvm_restore_msa)
+
+	.macro	kvm_restore_msa_upper	wr, off, base
+	.set	push
+	.set	noat
+#ifdef CONFIG_64BIT
+	ld	$1, \off(\base)
+	insert_d \wr, 1
+#elif defined(CONFIG_CPU_LITTLE_ENDIAN)
+	lw	$1, \off(\base)
+	insert_w \wr, 2
+	lw	$1, (\off+4)(\base)
+	insert_w \wr, 3
+#else /* CONFIG_CPU_BIG_ENDIAN */
+	lw	$1, (\off+4)(\base)
+	insert_w \wr, 2
+	lw	$1, \off(\base)
+	insert_w \wr, 3
+#endif
+	.set	pop
+	.endm
+
+LEAF(__kvm_restore_msa_upper)
+	kvm_restore_msa_upper	0,  VCPU_FPR0 +8, a0
+	kvm_restore_msa_upper	1,  VCPU_FPR1 +8, a0
+	kvm_restore_msa_upper	2,  VCPU_FPR2 +8, a0
+	kvm_restore_msa_upper	3,  VCPU_FPR3 +8, a0
+	kvm_restore_msa_upper	4,  VCPU_FPR4 +8, a0
+	kvm_restore_msa_upper	5,  VCPU_FPR5 +8, a0
+	kvm_restore_msa_upper	6,  VCPU_FPR6 +8, a0
+	kvm_restore_msa_upper	7,  VCPU_FPR7 +8, a0
+	kvm_restore_msa_upper	8,  VCPU_FPR8 +8, a0
+	kvm_restore_msa_upper	9,  VCPU_FPR9 +8, a0
+	kvm_restore_msa_upper	10, VCPU_FPR10+8, a0
+	kvm_restore_msa_upper	11, VCPU_FPR11+8, a0
+	kvm_restore_msa_upper	12, VCPU_FPR12+8, a0
+	kvm_restore_msa_upper	13, VCPU_FPR13+8, a0
+	kvm_restore_msa_upper	14, VCPU_FPR14+8, a0
+	kvm_restore_msa_upper	15, VCPU_FPR15+8, a0
+	kvm_restore_msa_upper	16, VCPU_FPR16+8, a0
+	kvm_restore_msa_upper	17, VCPU_FPR17+8, a0
+	kvm_restore_msa_upper	18, VCPU_FPR18+8, a0
+	kvm_restore_msa_upper	19, VCPU_FPR19+8, a0
+	kvm_restore_msa_upper	20, VCPU_FPR20+8, a0
+	kvm_restore_msa_upper	21, VCPU_FPR21+8, a0
+	kvm_restore_msa_upper	22, VCPU_FPR22+8, a0
+	kvm_restore_msa_upper	23, VCPU_FPR23+8, a0
+	kvm_restore_msa_upper	24, VCPU_FPR24+8, a0
+	kvm_restore_msa_upper	25, VCPU_FPR25+8, a0
+	kvm_restore_msa_upper	26, VCPU_FPR26+8, a0
+	kvm_restore_msa_upper	27, VCPU_FPR27+8, a0
+	kvm_restore_msa_upper	28, VCPU_FPR28+8, a0
+	kvm_restore_msa_upper	29, VCPU_FPR29+8, a0
+	kvm_restore_msa_upper	30, VCPU_FPR30+8, a0
+	kvm_restore_msa_upper	31, VCPU_FPR31+8, a0
+	jr	ra
+	 nop
+	END(__kvm_restore_msa_upper)
+
+LEAF(__kvm_restore_msacsr)
+	lw	t0, VCPU_MSA_CSR(a0)
+	/*
+	 * The ctcmsa must stay at this offset in __kvm_restore_msacsr.
+	 * See kvm_mips_csr_die_notify() which handles t0 containing a value
+	 * which triggers an MSA FP Exception, which must be stepped over and
+	 * ignored since the set cause bits must remain there for the guest.
+	 */
+	_ctcmsa	MSA_CSR, t0
+	jr	ra
+	 nop
+	END(__kvm_restore_msacsr)
diff --git a/arch/mips/kvm/stats.c b/arch/mips/kvm/stats.c
new file mode 100644
index 000000000..3e6682018
--- /dev/null
+++ b/arch/mips/kvm/stats.c
@@ -0,0 +1,63 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * KVM/MIPS: COP0 access histogram
+ *
+ * Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.
+ * Authors: Sanjay Lal <sanjayl@kymasys.com>
+ */
+
+#include <linux/kvm_host.h>
+
+char *kvm_cop0_str[N_MIPS_COPROC_REGS] = {
+	"Index",
+	"Random",
+	"EntryLo0",
+	"EntryLo1",
+	"Context",
+	"PG Mask",
+	"Wired",
+	"HWREna",
+	"BadVAddr",
+	"Count",
+	"EntryHI",
+	"Compare",
+	"Status",
+	"Cause",
+	"EXC PC",
+	"PRID",
+	"Config",
+	"LLAddr",
+	"Watch Lo",
+	"Watch Hi",
+	"X Context",
+	"Reserved",
+	"Impl Dep",
+	"Debug",
+	"DEPC",
+	"PerfCnt",
+	"ErrCtl",
+	"CacheErr",
+	"TagLo",
+	"TagHi",
+	"ErrorEPC",
+	"DESAVE"
+};
+
+void kvm_mips_dump_stats(struct kvm_vcpu *vcpu)
+{
+#ifdef CONFIG_KVM_MIPS_DEBUG_COP0_COUNTERS
+	int i, j;
+
+	kvm_info("\nKVM VCPU[%d] COP0 Access Profile:\n", vcpu->vcpu_id);
+	for (i = 0; i < N_MIPS_COPROC_REGS; i++) {
+		for (j = 0; j < N_MIPS_COPROC_SEL; j++) {
+			if (vcpu->arch.cop0.stat[i][j])
+				kvm_info("%s[%d]: %lu\n", kvm_cop0_str[i], j,
+					 vcpu->arch.cop0.stat[i][j]);
+		}
+	}
+#endif
+}
diff --git a/arch/mips/kvm/tlb.c b/arch/mips/kvm/tlb.c
new file mode 100644
index 000000000..4e91971da
--- /dev/null
+++ b/arch/mips/kvm/tlb.c
@@ -0,0 +1,525 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * KVM/MIPS TLB handling, this file is part of the Linux host kernel so that
+ * TLB handlers run from KSEG0
+ *
+ * Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.
+ * Authors: Sanjay Lal <sanjayl@kymasys.com>
+ */
+
+#include <linux/sched.h>
+#include <linux/smp.h>
+#include <linux/mm.h>
+#include <linux/delay.h>
+#include <linux/export.h>
+#include <linux/kvm_host.h>
+#include <linux/srcu.h>
+
+#include <asm/cpu.h>
+#include <asm/bootinfo.h>
+#include <asm/mipsregs.h>
+#include <asm/mmu_context.h>
+#include <asm/cacheflush.h>
+#include <asm/tlb.h>
+#include <asm/tlbdebug.h>
+
+#undef CONFIG_MIPS_MT
+#include <asm/r4kcache.h>
+#define CONFIG_MIPS_MT
+
+unsigned long GUESTID_MASK;
+EXPORT_SYMBOL_GPL(GUESTID_MASK);
+unsigned long GUESTID_FIRST_VERSION;
+EXPORT_SYMBOL_GPL(GUESTID_FIRST_VERSION);
+unsigned long GUESTID_VERSION_MASK;
+EXPORT_SYMBOL_GPL(GUESTID_VERSION_MASK);
+
+static u32 kvm_mips_get_root_asid(struct kvm_vcpu *vcpu)
+{
+	struct mm_struct *gpa_mm = &vcpu->kvm->arch.gpa_mm;
+
+	if (cpu_has_guestid)
+		return 0;
+	else
+		return cpu_asid(smp_processor_id(), gpa_mm);
+}
+
+static int _kvm_mips_host_tlb_inv(unsigned long entryhi)
+{
+	int idx;
+
+	write_c0_entryhi(entryhi);
+	mtc0_tlbw_hazard();
+
+	tlb_probe();
+	tlb_probe_hazard();
+	idx = read_c0_index();
+
+	BUG_ON(idx >= current_cpu_data.tlbsize);
+
+	if (idx >= 0) {
+		write_c0_entryhi(UNIQUE_ENTRYHI(idx));
+		write_c0_entrylo0(0);
+		write_c0_entrylo1(0);
+		mtc0_tlbw_hazard();
+
+		tlb_write_indexed();
+		tlbw_use_hazard();
+	}
+
+	return idx;
+}
+
+/* GuestID management */
+
+/**
+ * clear_root_gid() - Set GuestCtl1.RID for normal root operation.
+ */
+static inline void clear_root_gid(void)
+{
+	if (cpu_has_guestid) {
+		clear_c0_guestctl1(MIPS_GCTL1_RID);
+		mtc0_tlbw_hazard();
+	}
+}
+
+/**
+ * set_root_gid_to_guest_gid() - Set GuestCtl1.RID to match GuestCtl1.ID.
+ *
+ * Sets the root GuestID to match the current guest GuestID, for TLB operation
+ * on the GPA->RPA mappings in the root TLB.
+ *
+ * The caller must be sure to disable HTW while the root GID is set, and
+ * possibly longer if TLB registers are modified.
+ */
+static inline void set_root_gid_to_guest_gid(void)
+{
+	unsigned int guestctl1;
+
+	if (cpu_has_guestid) {
+		back_to_back_c0_hazard();
+		guestctl1 = read_c0_guestctl1();
+		guestctl1 = (guestctl1 & ~MIPS_GCTL1_RID) |
+			((guestctl1 & MIPS_GCTL1_ID) >> MIPS_GCTL1_ID_SHIFT)
+						     << MIPS_GCTL1_RID_SHIFT;
+		write_c0_guestctl1(guestctl1);
+		mtc0_tlbw_hazard();
+	}
+}
+
+int kvm_vz_host_tlb_inv(struct kvm_vcpu *vcpu, unsigned long va)
+{
+	int idx;
+	unsigned long flags, old_entryhi;
+
+	local_irq_save(flags);
+	htw_stop();
+
+	/* Set root GuestID for root probe and write of guest TLB entry */
+	set_root_gid_to_guest_gid();
+
+	old_entryhi = read_c0_entryhi();
+
+	idx = _kvm_mips_host_tlb_inv((va & VPN2_MASK) |
+				     kvm_mips_get_root_asid(vcpu));
+
+	write_c0_entryhi(old_entryhi);
+	clear_root_gid();
+	mtc0_tlbw_hazard();
+
+	htw_start();
+	local_irq_restore(flags);
+
+	/*
+	 * We don't want to get reserved instruction exceptions for missing tlb
+	 * entries.
+	 */
+	if (cpu_has_vtag_icache)
+		flush_icache_all();
+
+	if (idx > 0)
+		kvm_debug("%s: Invalidated root entryhi %#lx @ idx %d\n",
+			  __func__, (va & VPN2_MASK) |
+				    kvm_mips_get_root_asid(vcpu), idx);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(kvm_vz_host_tlb_inv);
+
+/**
+ * kvm_vz_guest_tlb_lookup() - Lookup a guest VZ TLB mapping.
+ * @vcpu:	KVM VCPU pointer.
+ * @gpa:	Guest virtual address in a TLB mapped guest segment.
+ * @gpa:	Pointer to output guest physical address it maps to.
+ *
+ * Converts a guest virtual address in a guest TLB mapped segment to a guest
+ * physical address, by probing the guest TLB.
+ *
+ * Returns:	0 if guest TLB mapping exists for @gva. *@gpa will have been
+ *		written.
+ *		-EFAULT if no guest TLB mapping exists for @gva. *@gpa may not
+ *		have been written.
+ */
+int kvm_vz_guest_tlb_lookup(struct kvm_vcpu *vcpu, unsigned long gva,
+			    unsigned long *gpa)
+{
+	unsigned long o_entryhi, o_entrylo[2], o_pagemask;
+	unsigned int o_index;
+	unsigned long entrylo[2], pagemask, pagemaskbit, pa;
+	unsigned long flags;
+	int index;
+
+	/* Probe the guest TLB for a mapping */
+	local_irq_save(flags);
+	/* Set root GuestID for root probe of guest TLB entry */
+	htw_stop();
+	set_root_gid_to_guest_gid();
+
+	o_entryhi = read_gc0_entryhi();
+	o_index = read_gc0_index();
+
+	write_gc0_entryhi((o_entryhi & 0x3ff) | (gva & ~0xfffl));
+	mtc0_tlbw_hazard();
+	guest_tlb_probe();
+	tlb_probe_hazard();
+
+	index = read_gc0_index();
+	if (index < 0) {
+		/* No match, fail */
+		write_gc0_entryhi(o_entryhi);
+		write_gc0_index(o_index);
+
+		clear_root_gid();
+		htw_start();
+		local_irq_restore(flags);
+		return -EFAULT;
+	}
+
+	/* Match! read the TLB entry */
+	o_entrylo[0] = read_gc0_entrylo0();
+	o_entrylo[1] = read_gc0_entrylo1();
+	o_pagemask = read_gc0_pagemask();
+
+	mtc0_tlbr_hazard();
+	guest_tlb_read();
+	tlb_read_hazard();
+
+	entrylo[0] = read_gc0_entrylo0();
+	entrylo[1] = read_gc0_entrylo1();
+	pagemask = ~read_gc0_pagemask() & ~0x1fffl;
+
+	write_gc0_entryhi(o_entryhi);
+	write_gc0_index(o_index);
+	write_gc0_entrylo0(o_entrylo[0]);
+	write_gc0_entrylo1(o_entrylo[1]);
+	write_gc0_pagemask(o_pagemask);
+
+	clear_root_gid();
+	htw_start();
+	local_irq_restore(flags);
+
+	/* Select one of the EntryLo values and interpret the GPA */
+	pagemaskbit = (pagemask ^ (pagemask & (pagemask - 1))) >> 1;
+	pa = entrylo[!!(gva & pagemaskbit)];
+
+	/*
+	 * TLB entry may have become invalid since TLB probe if physical FTLB
+	 * entries are shared between threads (e.g. I6400).
+	 */
+	if (!(pa & ENTRYLO_V))
+		return -EFAULT;
+
+	/*
+	 * Note, this doesn't take guest MIPS32 XPA into account, where PFN is
+	 * split with XI/RI in the middle.
+	 */
+	pa = (pa << 6) & ~0xfffl;
+	pa |= gva & ~(pagemask | pagemaskbit);
+
+	*gpa = pa;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(kvm_vz_guest_tlb_lookup);
+
+/**
+ * kvm_vz_local_flush_roottlb_all_guests() - Flush all root TLB entries for
+ * guests.
+ *
+ * Invalidate all entries in root tlb which are GPA mappings.
+ */
+void kvm_vz_local_flush_roottlb_all_guests(void)
+{
+	unsigned long flags;
+	unsigned long old_entryhi, old_pagemask, old_guestctl1;
+	int entry;
+
+	if (WARN_ON(!cpu_has_guestid))
+		return;
+
+	local_irq_save(flags);
+	htw_stop();
+
+	/* TLBR may clobber EntryHi.ASID, PageMask, and GuestCtl1.RID */
+	old_entryhi = read_c0_entryhi();
+	old_pagemask = read_c0_pagemask();
+	old_guestctl1 = read_c0_guestctl1();
+
+	/*
+	 * Invalidate guest entries in root TLB while leaving root entries
+	 * intact when possible.
+	 */
+	for (entry = 0; entry < current_cpu_data.tlbsize; entry++) {
+		write_c0_index(entry);
+		mtc0_tlbw_hazard();
+		tlb_read();
+		tlb_read_hazard();
+
+		/* Don't invalidate non-guest (RVA) mappings in the root TLB */
+		if (!(read_c0_guestctl1() & MIPS_GCTL1_RID))
+			continue;
+
+		/* Make sure all entries differ. */
+		write_c0_entryhi(UNIQUE_ENTRYHI(entry));
+		write_c0_entrylo0(0);
+		write_c0_entrylo1(0);
+		write_c0_guestctl1(0);
+		mtc0_tlbw_hazard();
+		tlb_write_indexed();
+	}
+
+	write_c0_entryhi(old_entryhi);
+	write_c0_pagemask(old_pagemask);
+	write_c0_guestctl1(old_guestctl1);
+	tlbw_use_hazard();
+
+	htw_start();
+	local_irq_restore(flags);
+}
+EXPORT_SYMBOL_GPL(kvm_vz_local_flush_roottlb_all_guests);
+
+/**
+ * kvm_vz_local_flush_guesttlb_all() - Flush all guest TLB entries.
+ *
+ * Invalidate all entries in guest tlb irrespective of guestid.
+ */
+void kvm_vz_local_flush_guesttlb_all(void)
+{
+	unsigned long flags;
+	unsigned long old_index;
+	unsigned long old_entryhi;
+	unsigned long old_entrylo[2];
+	unsigned long old_pagemask;
+	int entry;
+	u64 cvmmemctl2 = 0;
+
+	local_irq_save(flags);
+
+	/* Preserve all clobbered guest registers */
+	old_index = read_gc0_index();
+	old_entryhi = read_gc0_entryhi();
+	old_entrylo[0] = read_gc0_entrylo0();
+	old_entrylo[1] = read_gc0_entrylo1();
+	old_pagemask = read_gc0_pagemask();
+
+	switch (current_cpu_type()) {
+	case CPU_CAVIUM_OCTEON3:
+		/* Inhibit machine check due to multiple matching TLB entries */
+		cvmmemctl2 = read_c0_cvmmemctl2();
+		cvmmemctl2 |= CVMMEMCTL2_INHIBITTS;
+		write_c0_cvmmemctl2(cvmmemctl2);
+		break;
+	}
+
+	/* Invalidate guest entries in guest TLB */
+	write_gc0_entrylo0(0);
+	write_gc0_entrylo1(0);
+	write_gc0_pagemask(0);
+	for (entry = 0; entry < current_cpu_data.guest.tlbsize; entry++) {
+		/* Make sure all entries differ. */
+		write_gc0_index(entry);
+		write_gc0_entryhi(UNIQUE_GUEST_ENTRYHI(entry));
+		mtc0_tlbw_hazard();
+		guest_tlb_write_indexed();
+	}
+
+	if (cvmmemctl2) {
+		cvmmemctl2 &= ~CVMMEMCTL2_INHIBITTS;
+		write_c0_cvmmemctl2(cvmmemctl2);
+	}
+
+	write_gc0_index(old_index);
+	write_gc0_entryhi(old_entryhi);
+	write_gc0_entrylo0(old_entrylo[0]);
+	write_gc0_entrylo1(old_entrylo[1]);
+	write_gc0_pagemask(old_pagemask);
+	tlbw_use_hazard();
+
+	local_irq_restore(flags);
+}
+EXPORT_SYMBOL_GPL(kvm_vz_local_flush_guesttlb_all);
+
+/**
+ * kvm_vz_save_guesttlb() - Save a range of guest TLB entries.
+ * @buf:	Buffer to write TLB entries into.
+ * @index:	Start index.
+ * @count:	Number of entries to save.
+ *
+ * Save a range of guest TLB entries. The caller must ensure interrupts are
+ * disabled.
+ */
+void kvm_vz_save_guesttlb(struct kvm_mips_tlb *buf, unsigned int index,
+			  unsigned int count)
+{
+	unsigned int end = index + count;
+	unsigned long old_entryhi, old_entrylo0, old_entrylo1, old_pagemask;
+	unsigned int guestctl1 = 0;
+	int old_index, i;
+
+	/* Save registers we're about to clobber */
+	old_index = read_gc0_index();
+	old_entryhi = read_gc0_entryhi();
+	old_entrylo0 = read_gc0_entrylo0();
+	old_entrylo1 = read_gc0_entrylo1();
+	old_pagemask = read_gc0_pagemask();
+
+	/* Set root GuestID for root probe */
+	htw_stop();
+	set_root_gid_to_guest_gid();
+	if (cpu_has_guestid)
+		guestctl1 = read_c0_guestctl1();
+
+	/* Read each entry from guest TLB */
+	for (i = index; i < end; ++i, ++buf) {
+		write_gc0_index(i);
+
+		mtc0_tlbr_hazard();
+		guest_tlb_read();
+		tlb_read_hazard();
+
+		if (cpu_has_guestid &&
+		    (read_c0_guestctl1() ^ guestctl1) & MIPS_GCTL1_RID) {
+			/* Entry invalid or belongs to another guest */
+			buf->tlb_hi = UNIQUE_GUEST_ENTRYHI(i);
+			buf->tlb_lo[0] = 0;
+			buf->tlb_lo[1] = 0;
+			buf->tlb_mask = 0;
+		} else {
+			/* Entry belongs to the right guest */
+			buf->tlb_hi = read_gc0_entryhi();
+			buf->tlb_lo[0] = read_gc0_entrylo0();
+			buf->tlb_lo[1] = read_gc0_entrylo1();
+			buf->tlb_mask = read_gc0_pagemask();
+		}
+	}
+
+	/* Clear root GuestID again */
+	clear_root_gid();
+	htw_start();
+
+	/* Restore clobbered registers */
+	write_gc0_index(old_index);
+	write_gc0_entryhi(old_entryhi);
+	write_gc0_entrylo0(old_entrylo0);
+	write_gc0_entrylo1(old_entrylo1);
+	write_gc0_pagemask(old_pagemask);
+
+	tlbw_use_hazard();
+}
+EXPORT_SYMBOL_GPL(kvm_vz_save_guesttlb);
+
+/**
+ * kvm_vz_load_guesttlb() - Save a range of guest TLB entries.
+ * @buf:	Buffer to read TLB entries from.
+ * @index:	Start index.
+ * @count:	Number of entries to load.
+ *
+ * Load a range of guest TLB entries. The caller must ensure interrupts are
+ * disabled.
+ */
+void kvm_vz_load_guesttlb(const struct kvm_mips_tlb *buf, unsigned int index,
+			  unsigned int count)
+{
+	unsigned int end = index + count;
+	unsigned long old_entryhi, old_entrylo0, old_entrylo1, old_pagemask;
+	int old_index, i;
+
+	/* Save registers we're about to clobber */
+	old_index = read_gc0_index();
+	old_entryhi = read_gc0_entryhi();
+	old_entrylo0 = read_gc0_entrylo0();
+	old_entrylo1 = read_gc0_entrylo1();
+	old_pagemask = read_gc0_pagemask();
+
+	/* Set root GuestID for root probe */
+	htw_stop();
+	set_root_gid_to_guest_gid();
+
+	/* Write each entry to guest TLB */
+	for (i = index; i < end; ++i, ++buf) {
+		write_gc0_index(i);
+		write_gc0_entryhi(buf->tlb_hi);
+		write_gc0_entrylo0(buf->tlb_lo[0]);
+		write_gc0_entrylo1(buf->tlb_lo[1]);
+		write_gc0_pagemask(buf->tlb_mask);
+
+		mtc0_tlbw_hazard();
+		guest_tlb_write_indexed();
+	}
+
+	/* Clear root GuestID again */
+	clear_root_gid();
+	htw_start();
+
+	/* Restore clobbered registers */
+	write_gc0_index(old_index);
+	write_gc0_entryhi(old_entryhi);
+	write_gc0_entrylo0(old_entrylo0);
+	write_gc0_entrylo1(old_entrylo1);
+	write_gc0_pagemask(old_pagemask);
+
+	tlbw_use_hazard();
+}
+EXPORT_SYMBOL_GPL(kvm_vz_load_guesttlb);
+
+#ifdef CONFIG_CPU_LOONGSON64
+void kvm_loongson_clear_guest_vtlb(void)
+{
+	int idx = read_gc0_index();
+
+	/* Set root GuestID for root probe and write of guest TLB entry */
+	set_root_gid_to_guest_gid();
+
+	write_gc0_index(0);
+	guest_tlbinvf();
+	write_gc0_index(idx);
+
+	clear_root_gid();
+	set_c0_diag(LOONGSON_DIAG_ITLB | LOONGSON_DIAG_DTLB);
+}
+EXPORT_SYMBOL_GPL(kvm_loongson_clear_guest_vtlb);
+
+void kvm_loongson_clear_guest_ftlb(void)
+{
+	int i;
+	int idx = read_gc0_index();
+
+	/* Set root GuestID for root probe and write of guest TLB entry */
+	set_root_gid_to_guest_gid();
+
+	for (i = current_cpu_data.tlbsizevtlb;
+	     i < (current_cpu_data.tlbsizevtlb +
+		     current_cpu_data.tlbsizeftlbsets);
+	     i++) {
+		write_gc0_index(i);
+		guest_tlbinvf();
+	}
+	write_gc0_index(idx);
+
+	clear_root_gid();
+	set_c0_diag(LOONGSON_DIAG_ITLB | LOONGSON_DIAG_DTLB);
+}
+EXPORT_SYMBOL_GPL(kvm_loongson_clear_guest_ftlb);
+#endif
diff --git a/arch/mips/kvm/trace.h b/arch/mips/kvm/trace.h
new file mode 100644
index 000000000..136c3535a
--- /dev/null
+++ b/arch/mips/kvm/trace.h
@@ -0,0 +1,346 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.
+ * Authors: Sanjay Lal <sanjayl@kymasys.com>
+ */
+
+#if !defined(_TRACE_KVM_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_KVM_H
+
+#include <linux/tracepoint.h>
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM kvm
+#define TRACE_INCLUDE_PATH .
+#define TRACE_INCLUDE_FILE trace
+
+/*
+ * arch/mips/kvm/mips.c
+ */
+extern bool kvm_trace_guest_mode_change;
+int kvm_guest_mode_change_trace_reg(void);
+void kvm_guest_mode_change_trace_unreg(void);
+
+/*
+ * Tracepoints for VM enters
+ */
+DECLARE_EVENT_CLASS(kvm_transition,
+	TP_PROTO(struct kvm_vcpu *vcpu),
+	TP_ARGS(vcpu),
+	TP_STRUCT__entry(
+		__field(unsigned long, pc)
+	),
+
+	TP_fast_assign(
+		__entry->pc = vcpu->arch.pc;
+	),
+
+	TP_printk("PC: 0x%08lx",
+		  __entry->pc)
+);
+
+DEFINE_EVENT(kvm_transition, kvm_enter,
+	     TP_PROTO(struct kvm_vcpu *vcpu),
+	     TP_ARGS(vcpu));
+
+DEFINE_EVENT(kvm_transition, kvm_reenter,
+	     TP_PROTO(struct kvm_vcpu *vcpu),
+	     TP_ARGS(vcpu));
+
+DEFINE_EVENT(kvm_transition, kvm_out,
+	     TP_PROTO(struct kvm_vcpu *vcpu),
+	     TP_ARGS(vcpu));
+
+/* The first 32 exit reasons correspond to Cause.ExcCode */
+#define KVM_TRACE_EXIT_INT		 0
+#define KVM_TRACE_EXIT_TLBMOD		 1
+#define KVM_TRACE_EXIT_TLBMISS_LD	 2
+#define KVM_TRACE_EXIT_TLBMISS_ST	 3
+#define KVM_TRACE_EXIT_ADDRERR_LD	 4
+#define KVM_TRACE_EXIT_ADDRERR_ST	 5
+#define KVM_TRACE_EXIT_SYSCALL		 8
+#define KVM_TRACE_EXIT_BREAK_INST	 9
+#define KVM_TRACE_EXIT_RESVD_INST	10
+#define KVM_TRACE_EXIT_COP_UNUSABLE	11
+#define KVM_TRACE_EXIT_TRAP_INST	13
+#define KVM_TRACE_EXIT_MSA_FPE		14
+#define KVM_TRACE_EXIT_FPE		15
+#define KVM_TRACE_EXIT_MSA_DISABLED	21
+#define KVM_TRACE_EXIT_GUEST_EXIT	27
+/* Further exit reasons */
+#define KVM_TRACE_EXIT_WAIT		32
+#define KVM_TRACE_EXIT_CACHE		33
+#define KVM_TRACE_EXIT_SIGNAL		34
+/* 32 exit reasons correspond to GuestCtl0.GExcCode (VZ) */
+#define KVM_TRACE_EXIT_GEXCCODE_BASE	64
+#define KVM_TRACE_EXIT_GPSI		64	/*  0 */
+#define KVM_TRACE_EXIT_GSFC		65	/*  1 */
+#define KVM_TRACE_EXIT_HC		66	/*  2 */
+#define KVM_TRACE_EXIT_GRR		67	/*  3 */
+#define KVM_TRACE_EXIT_GVA		72	/*  8 */
+#define KVM_TRACE_EXIT_GHFC		73	/*  9 */
+#define KVM_TRACE_EXIT_GPA		74	/* 10 */
+
+/* Tracepoints for VM exits */
+#define kvm_trace_symbol_exit_types				\
+	{ KVM_TRACE_EXIT_INT,		"Interrupt" },		\
+	{ KVM_TRACE_EXIT_TLBMOD,	"TLB Mod" },		\
+	{ KVM_TRACE_EXIT_TLBMISS_LD,	"TLB Miss (LD)" },	\
+	{ KVM_TRACE_EXIT_TLBMISS_ST,	"TLB Miss (ST)" },	\
+	{ KVM_TRACE_EXIT_ADDRERR_LD,	"Address Error (LD)" },	\
+	{ KVM_TRACE_EXIT_ADDRERR_ST,	"Address Err (ST)" },	\
+	{ KVM_TRACE_EXIT_SYSCALL,	"System Call" },	\
+	{ KVM_TRACE_EXIT_BREAK_INST,	"Break Inst" },		\
+	{ KVM_TRACE_EXIT_RESVD_INST,	"Reserved Inst" },	\
+	{ KVM_TRACE_EXIT_COP_UNUSABLE,	"COP0/1 Unusable" },	\
+	{ KVM_TRACE_EXIT_TRAP_INST,	"Trap Inst" },		\
+	{ KVM_TRACE_EXIT_MSA_FPE,	"MSA FPE" },		\
+	{ KVM_TRACE_EXIT_FPE,		"FPE" },		\
+	{ KVM_TRACE_EXIT_MSA_DISABLED,	"MSA Disabled" },	\
+	{ KVM_TRACE_EXIT_GUEST_EXIT,	"Guest Exit" },		\
+	{ KVM_TRACE_EXIT_WAIT,		"WAIT" },		\
+	{ KVM_TRACE_EXIT_CACHE,		"CACHE" },		\
+	{ KVM_TRACE_EXIT_SIGNAL,	"Signal" },		\
+	{ KVM_TRACE_EXIT_GPSI,		"GPSI" },		\
+	{ KVM_TRACE_EXIT_GSFC,		"GSFC" },		\
+	{ KVM_TRACE_EXIT_HC,		"HC" },			\
+	{ KVM_TRACE_EXIT_GRR,		"GRR" },		\
+	{ KVM_TRACE_EXIT_GVA,		"GVA" },		\
+	{ KVM_TRACE_EXIT_GHFC,		"GHFC" },		\
+	{ KVM_TRACE_EXIT_GPA,		"GPA" }
+
+TRACE_EVENT(kvm_exit,
+	    TP_PROTO(struct kvm_vcpu *vcpu, unsigned int reason),
+	    TP_ARGS(vcpu, reason),
+	    TP_STRUCT__entry(
+			__field(unsigned long, pc)
+			__field(unsigned int, reason)
+	    ),
+
+	    TP_fast_assign(
+			__entry->pc = vcpu->arch.pc;
+			__entry->reason = reason;
+	    ),
+
+	    TP_printk("[%s]PC: 0x%08lx",
+		      __print_symbolic(__entry->reason,
+				       kvm_trace_symbol_exit_types),
+		      __entry->pc)
+);
+
+#define KVM_TRACE_MFC0		0
+#define KVM_TRACE_MTC0		1
+#define KVM_TRACE_DMFC0		2
+#define KVM_TRACE_DMTC0		3
+#define KVM_TRACE_RDHWR		4
+
+#define KVM_TRACE_HWR_COP0	0
+#define KVM_TRACE_HWR_HWR	1
+
+#define KVM_TRACE_COP0(REG, SEL)	((KVM_TRACE_HWR_COP0 << 8) |	\
+					 ((REG) << 3) | (SEL))
+#define KVM_TRACE_HWR(REG, SEL)		((KVM_TRACE_HWR_HWR  << 8) |	\
+					 ((REG) << 3) | (SEL))
+
+#define kvm_trace_symbol_hwr_ops				\
+	{ KVM_TRACE_MFC0,		"MFC0" },		\
+	{ KVM_TRACE_MTC0,		"MTC0" },		\
+	{ KVM_TRACE_DMFC0,		"DMFC0" },		\
+	{ KVM_TRACE_DMTC0,		"DMTC0" },		\
+	{ KVM_TRACE_RDHWR,		"RDHWR" }
+
+#define kvm_trace_symbol_hwr_cop				\
+	{ KVM_TRACE_HWR_COP0,		"COP0" },		\
+	{ KVM_TRACE_HWR_HWR,		"HWR" }
+
+#define kvm_trace_symbol_hwr_regs				\
+	{ KVM_TRACE_COP0( 0, 0),	"Index" },		\
+	{ KVM_TRACE_COP0( 2, 0),	"EntryLo0" },		\
+	{ KVM_TRACE_COP0( 3, 0),	"EntryLo1" },		\
+	{ KVM_TRACE_COP0( 4, 0),	"Context" },		\
+	{ KVM_TRACE_COP0( 4, 2),	"UserLocal" },		\
+	{ KVM_TRACE_COP0( 5, 0),	"PageMask" },		\
+	{ KVM_TRACE_COP0( 6, 0),	"Wired" },		\
+	{ KVM_TRACE_COP0( 7, 0),	"HWREna" },		\
+	{ KVM_TRACE_COP0( 8, 0),	"BadVAddr" },		\
+	{ KVM_TRACE_COP0( 9, 0),	"Count" },		\
+	{ KVM_TRACE_COP0(10, 0),	"EntryHi" },		\
+	{ KVM_TRACE_COP0(11, 0),	"Compare" },		\
+	{ KVM_TRACE_COP0(12, 0),	"Status" },		\
+	{ KVM_TRACE_COP0(12, 1),	"IntCtl" },		\
+	{ KVM_TRACE_COP0(12, 2),	"SRSCtl" },		\
+	{ KVM_TRACE_COP0(13, 0),	"Cause" },		\
+	{ KVM_TRACE_COP0(14, 0),	"EPC" },		\
+	{ KVM_TRACE_COP0(15, 0),	"PRId" },		\
+	{ KVM_TRACE_COP0(15, 1),	"EBase" },		\
+	{ KVM_TRACE_COP0(16, 0),	"Config" },		\
+	{ KVM_TRACE_COP0(16, 1),	"Config1" },		\
+	{ KVM_TRACE_COP0(16, 2),	"Config2" },		\
+	{ KVM_TRACE_COP0(16, 3),	"Config3" },		\
+	{ KVM_TRACE_COP0(16, 4),	"Config4" },		\
+	{ KVM_TRACE_COP0(16, 5),	"Config5" },		\
+	{ KVM_TRACE_COP0(16, 7),	"Config7" },		\
+	{ KVM_TRACE_COP0(17, 1),	"MAAR" },		\
+	{ KVM_TRACE_COP0(17, 2),	"MAARI" },		\
+	{ KVM_TRACE_COP0(26, 0),	"ECC" },		\
+	{ KVM_TRACE_COP0(30, 0),	"ErrorEPC" },		\
+	{ KVM_TRACE_COP0(31, 2),	"KScratch1" },		\
+	{ KVM_TRACE_COP0(31, 3),	"KScratch2" },		\
+	{ KVM_TRACE_COP0(31, 4),	"KScratch3" },		\
+	{ KVM_TRACE_COP0(31, 5),	"KScratch4" },		\
+	{ KVM_TRACE_COP0(31, 6),	"KScratch5" },		\
+	{ KVM_TRACE_COP0(31, 7),	"KScratch6" },		\
+	{ KVM_TRACE_HWR( 0, 0),		"CPUNum" },		\
+	{ KVM_TRACE_HWR( 1, 0),		"SYNCI_Step" },		\
+	{ KVM_TRACE_HWR( 2, 0),		"CC" },			\
+	{ KVM_TRACE_HWR( 3, 0),		"CCRes" },		\
+	{ KVM_TRACE_HWR(29, 0),		"ULR" }
+
+TRACE_EVENT(kvm_hwr,
+	    TP_PROTO(struct kvm_vcpu *vcpu, unsigned int op, unsigned int reg,
+		     unsigned long val),
+	    TP_ARGS(vcpu, op, reg, val),
+	    TP_STRUCT__entry(
+			__field(unsigned long, val)
+			__field(u16, reg)
+			__field(u8, op)
+	    ),
+
+	    TP_fast_assign(
+			__entry->val = val;
+			__entry->reg = reg;
+			__entry->op = op;
+	    ),
+
+	    TP_printk("%s %s (%s:%u:%u) 0x%08lx",
+		      __print_symbolic(__entry->op,
+				       kvm_trace_symbol_hwr_ops),
+		      __print_symbolic(__entry->reg,
+				       kvm_trace_symbol_hwr_regs),
+		      __print_symbolic(__entry->reg >> 8,
+				       kvm_trace_symbol_hwr_cop),
+		      (__entry->reg >> 3) & 0x1f,
+		      __entry->reg & 0x7,
+		      __entry->val)
+);
+
+#define KVM_TRACE_AUX_RESTORE		0
+#define KVM_TRACE_AUX_SAVE		1
+#define KVM_TRACE_AUX_ENABLE		2
+#define KVM_TRACE_AUX_DISABLE		3
+#define KVM_TRACE_AUX_DISCARD		4
+
+#define KVM_TRACE_AUX_FPU		1
+#define KVM_TRACE_AUX_MSA		2
+#define KVM_TRACE_AUX_FPU_MSA		3
+
+#define kvm_trace_symbol_aux_op		\
+	{ KVM_TRACE_AUX_RESTORE, "restore" },	\
+	{ KVM_TRACE_AUX_SAVE,    "save" },	\
+	{ KVM_TRACE_AUX_ENABLE,  "enable" },	\
+	{ KVM_TRACE_AUX_DISABLE, "disable" },	\
+	{ KVM_TRACE_AUX_DISCARD, "discard" }
+
+#define kvm_trace_symbol_aux_state		\
+	{ KVM_TRACE_AUX_FPU,     "FPU" },	\
+	{ KVM_TRACE_AUX_MSA,     "MSA" },	\
+	{ KVM_TRACE_AUX_FPU_MSA, "FPU & MSA" }
+
+TRACE_EVENT(kvm_aux,
+	    TP_PROTO(struct kvm_vcpu *vcpu, unsigned int op,
+		     unsigned int state),
+	    TP_ARGS(vcpu, op, state),
+	    TP_STRUCT__entry(
+			__field(unsigned long, pc)
+			__field(u8, op)
+			__field(u8, state)
+	    ),
+
+	    TP_fast_assign(
+			__entry->pc = vcpu->arch.pc;
+			__entry->op = op;
+			__entry->state = state;
+	    ),
+
+	    TP_printk("%s %s PC: 0x%08lx",
+		      __print_symbolic(__entry->op,
+				       kvm_trace_symbol_aux_op),
+		      __print_symbolic(__entry->state,
+				       kvm_trace_symbol_aux_state),
+		      __entry->pc)
+);
+
+TRACE_EVENT(kvm_asid_change,
+	    TP_PROTO(struct kvm_vcpu *vcpu, unsigned int old_asid,
+		     unsigned int new_asid),
+	    TP_ARGS(vcpu, old_asid, new_asid),
+	    TP_STRUCT__entry(
+			__field(unsigned long, pc)
+			__field(u8, old_asid)
+			__field(u8, new_asid)
+	    ),
+
+	    TP_fast_assign(
+			__entry->pc = vcpu->arch.pc;
+			__entry->old_asid = old_asid;
+			__entry->new_asid = new_asid;
+	    ),
+
+	    TP_printk("PC: 0x%08lx old: 0x%02x new: 0x%02x",
+		      __entry->pc,
+		      __entry->old_asid,
+		      __entry->new_asid)
+);
+
+TRACE_EVENT(kvm_guestid_change,
+	    TP_PROTO(struct kvm_vcpu *vcpu, unsigned int guestid),
+	    TP_ARGS(vcpu, guestid),
+	    TP_STRUCT__entry(
+			__field(unsigned int, guestid)
+	    ),
+
+	    TP_fast_assign(
+			__entry->guestid = guestid;
+	    ),
+
+	    TP_printk("GuestID: 0x%02x",
+		      __entry->guestid)
+);
+
+TRACE_EVENT_FN(kvm_guest_mode_change,
+	    TP_PROTO(struct kvm_vcpu *vcpu),
+	    TP_ARGS(vcpu),
+	    TP_STRUCT__entry(
+			__field(unsigned long, epc)
+			__field(unsigned long, pc)
+			__field(unsigned long, badvaddr)
+			__field(unsigned int, status)
+			__field(unsigned int, cause)
+	    ),
+
+	    TP_fast_assign(
+			__entry->epc = kvm_read_c0_guest_epc(&vcpu->arch.cop0);
+			__entry->pc = vcpu->arch.pc;
+			__entry->badvaddr = kvm_read_c0_guest_badvaddr(&vcpu->arch.cop0);
+			__entry->status = kvm_read_c0_guest_status(&vcpu->arch.cop0);
+			__entry->cause = kvm_read_c0_guest_cause(&vcpu->arch.cop0);
+	    ),
+
+	    TP_printk("EPC: 0x%08lx PC: 0x%08lx Status: 0x%08x Cause: 0x%08x BadVAddr: 0x%08lx",
+		      __entry->epc,
+		      __entry->pc,
+		      __entry->status,
+		      __entry->cause,
+		      __entry->badvaddr),
+
+	    kvm_guest_mode_change_trace_reg,
+	    kvm_guest_mode_change_trace_unreg
+);
+
+#endif /* _TRACE_KVM_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
diff --git a/arch/mips/kvm/vz.c b/arch/mips/kvm/vz.c
new file mode 100644
index 000000000..99d5a71e4
--- /dev/null
+++ b/arch/mips/kvm/vz.c
@@ -0,0 +1,3325 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * KVM/MIPS: Support for hardware virtualization extensions
+ *
+ * Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.
+ * Authors: Yann Le Du <ledu@kymasys.com>
+ */
+
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/preempt.h>
+#include <linux/vmalloc.h>
+#include <asm/cacheflush.h>
+#include <asm/cacheops.h>
+#include <asm/cmpxchg.h>
+#include <asm/fpu.h>
+#include <asm/hazards.h>
+#include <asm/inst.h>
+#include <asm/mmu_context.h>
+#include <asm/r4kcache.h>
+#include <asm/time.h>
+#include <asm/tlb.h>
+#include <asm/tlbex.h>
+
+#include <linux/kvm_host.h>
+
+#include "interrupt.h"
+#ifdef CONFIG_CPU_LOONGSON64
+#include "loongson_regs.h"
+#endif
+
+#include "trace.h"
+
+/* Pointers to last VCPU loaded on each physical CPU */
+static struct kvm_vcpu *last_vcpu[NR_CPUS];
+/* Pointers to last VCPU executed on each physical CPU */
+static struct kvm_vcpu *last_exec_vcpu[NR_CPUS];
+
+/*
+ * Number of guest VTLB entries to use, so we can catch inconsistency between
+ * CPUs.
+ */
+static unsigned int kvm_vz_guest_vtlb_size;
+
+static inline long kvm_vz_read_gc0_ebase(void)
+{
+	if (sizeof(long) == 8 && cpu_has_ebase_wg)
+		return read_gc0_ebase_64();
+	else
+		return read_gc0_ebase();
+}
+
+static inline void kvm_vz_write_gc0_ebase(long v)
+{
+	/*
+	 * First write with WG=1 to write upper bits, then write again in case
+	 * WG should be left at 0.
+	 * write_gc0_ebase_64() is no longer UNDEFINED since R6.
+	 */
+	if (sizeof(long) == 8 &&
+	    (cpu_has_mips64r6 || cpu_has_ebase_wg)) {
+		write_gc0_ebase_64(v | MIPS_EBASE_WG);
+		write_gc0_ebase_64(v);
+	} else {
+		write_gc0_ebase(v | MIPS_EBASE_WG);
+		write_gc0_ebase(v);
+	}
+}
+
+/*
+ * These Config bits may be writable by the guest:
+ * Config:	[K23, KU] (!TLB), K0
+ * Config1:	(none)
+ * Config2:	[TU, SU] (impl)
+ * Config3:	ISAOnExc
+ * Config4:	FTLBPageSize
+ * Config5:	K, CV, MSAEn, UFE, FRE, SBRI, UFR
+ */
+
+static inline unsigned int kvm_vz_config_guest_wrmask(struct kvm_vcpu *vcpu)
+{
+	return CONF_CM_CMASK;
+}
+
+static inline unsigned int kvm_vz_config1_guest_wrmask(struct kvm_vcpu *vcpu)
+{
+	return 0;
+}
+
+static inline unsigned int kvm_vz_config2_guest_wrmask(struct kvm_vcpu *vcpu)
+{
+	return 0;
+}
+
+static inline unsigned int kvm_vz_config3_guest_wrmask(struct kvm_vcpu *vcpu)
+{
+	return MIPS_CONF3_ISA_OE;
+}
+
+static inline unsigned int kvm_vz_config4_guest_wrmask(struct kvm_vcpu *vcpu)
+{
+	/* no need to be exact */
+	return MIPS_CONF4_VFTLBPAGESIZE;
+}
+
+static inline unsigned int kvm_vz_config5_guest_wrmask(struct kvm_vcpu *vcpu)
+{
+	unsigned int mask = MIPS_CONF5_K | MIPS_CONF5_CV | MIPS_CONF5_SBRI;
+
+	/* Permit MSAEn changes if MSA supported and enabled */
+	if (kvm_mips_guest_has_msa(&vcpu->arch))
+		mask |= MIPS_CONF5_MSAEN;
+
+	/*
+	 * Permit guest FPU mode changes if FPU is enabled and the relevant
+	 * feature exists according to FIR register.
+	 */
+	if (kvm_mips_guest_has_fpu(&vcpu->arch)) {
+		if (cpu_has_ufr)
+			mask |= MIPS_CONF5_UFR;
+		if (cpu_has_fre)
+			mask |= MIPS_CONF5_FRE | MIPS_CONF5_UFE;
+	}
+
+	return mask;
+}
+
+static inline unsigned int kvm_vz_config6_guest_wrmask(struct kvm_vcpu *vcpu)
+{
+	return LOONGSON_CONF6_INTIMER | LOONGSON_CONF6_EXTIMER;
+}
+
+/*
+ * VZ optionally allows these additional Config bits to be written by root:
+ * Config:	M, [MT]
+ * Config1:	M, [MMUSize-1, C2, MD, PC, WR, CA], FP
+ * Config2:	M
+ * Config3:	M, MSAP, [BPG], ULRI, [DSP2P, DSPP], CTXTC, [ITL, LPA, VEIC,
+ *		VInt, SP, CDMM, MT, SM, TL]
+ * Config4:	M, [VTLBSizeExt, MMUSizeExt]
+ * Config5:	MRP
+ */
+
+static inline unsigned int kvm_vz_config_user_wrmask(struct kvm_vcpu *vcpu)
+{
+	return kvm_vz_config_guest_wrmask(vcpu) | MIPS_CONF_M;
+}
+
+static inline unsigned int kvm_vz_config1_user_wrmask(struct kvm_vcpu *vcpu)
+{
+	unsigned int mask = kvm_vz_config1_guest_wrmask(vcpu) | MIPS_CONF_M;
+
+	/* Permit FPU to be present if FPU is supported */
+	if (kvm_mips_guest_can_have_fpu(&vcpu->arch))
+		mask |= MIPS_CONF1_FP;
+
+	return mask;
+}
+
+static inline unsigned int kvm_vz_config2_user_wrmask(struct kvm_vcpu *vcpu)
+{
+	return kvm_vz_config2_guest_wrmask(vcpu) | MIPS_CONF_M;
+}
+
+static inline unsigned int kvm_vz_config3_user_wrmask(struct kvm_vcpu *vcpu)
+{
+	unsigned int mask = kvm_vz_config3_guest_wrmask(vcpu) | MIPS_CONF_M |
+		MIPS_CONF3_ULRI | MIPS_CONF3_CTXTC;
+
+	/* Permit MSA to be present if MSA is supported */
+	if (kvm_mips_guest_can_have_msa(&vcpu->arch))
+		mask |= MIPS_CONF3_MSA;
+
+	return mask;
+}
+
+static inline unsigned int kvm_vz_config4_user_wrmask(struct kvm_vcpu *vcpu)
+{
+	return kvm_vz_config4_guest_wrmask(vcpu) | MIPS_CONF_M;
+}
+
+static inline unsigned int kvm_vz_config5_user_wrmask(struct kvm_vcpu *vcpu)
+{
+	return kvm_vz_config5_guest_wrmask(vcpu) | MIPS_CONF5_MRP;
+}
+
+static inline unsigned int kvm_vz_config6_user_wrmask(struct kvm_vcpu *vcpu)
+{
+	return kvm_vz_config6_guest_wrmask(vcpu) |
+		LOONGSON_CONF6_SFBEN | LOONGSON_CONF6_FTLBDIS;
+}
+
+static gpa_t kvm_vz_gva_to_gpa_cb(gva_t gva)
+{
+	/* VZ guest has already converted gva to gpa */
+	return gva;
+}
+
+static void kvm_vz_queue_irq(struct kvm_vcpu *vcpu, unsigned int priority)
+{
+	set_bit(priority, &vcpu->arch.pending_exceptions);
+	clear_bit(priority, &vcpu->arch.pending_exceptions_clr);
+}
+
+static void kvm_vz_dequeue_irq(struct kvm_vcpu *vcpu, unsigned int priority)
+{
+	clear_bit(priority, &vcpu->arch.pending_exceptions);
+	set_bit(priority, &vcpu->arch.pending_exceptions_clr);
+}
+
+static void kvm_vz_queue_timer_int_cb(struct kvm_vcpu *vcpu)
+{
+	/*
+	 * timer expiry is asynchronous to vcpu execution therefore defer guest
+	 * cp0 accesses
+	 */
+	kvm_vz_queue_irq(vcpu, MIPS_EXC_INT_TIMER);
+}
+
+static void kvm_vz_dequeue_timer_int_cb(struct kvm_vcpu *vcpu)
+{
+	/*
+	 * timer expiry is asynchronous to vcpu execution therefore defer guest
+	 * cp0 accesses
+	 */
+	kvm_vz_dequeue_irq(vcpu, MIPS_EXC_INT_TIMER);
+}
+
+static void kvm_vz_queue_io_int_cb(struct kvm_vcpu *vcpu,
+				   struct kvm_mips_interrupt *irq)
+{
+	int intr = (int)irq->irq;
+
+	/*
+	 * interrupts are asynchronous to vcpu execution therefore defer guest
+	 * cp0 accesses
+	 */
+	kvm_vz_queue_irq(vcpu, kvm_irq_to_priority(intr));
+}
+
+static void kvm_vz_dequeue_io_int_cb(struct kvm_vcpu *vcpu,
+				     struct kvm_mips_interrupt *irq)
+{
+	int intr = (int)irq->irq;
+
+	/*
+	 * interrupts are asynchronous to vcpu execution therefore defer guest
+	 * cp0 accesses
+	 */
+	kvm_vz_dequeue_irq(vcpu, kvm_irq_to_priority(-intr));
+}
+
+static int kvm_vz_irq_deliver_cb(struct kvm_vcpu *vcpu, unsigned int priority,
+				 u32 cause)
+{
+	u32 irq = (priority < MIPS_EXC_MAX) ?
+		kvm_priority_to_irq[priority] : 0;
+
+	switch (priority) {
+	case MIPS_EXC_INT_TIMER:
+		set_gc0_cause(C_TI);
+		break;
+
+	case MIPS_EXC_INT_IO_1:
+	case MIPS_EXC_INT_IO_2:
+	case MIPS_EXC_INT_IPI_1:
+	case MIPS_EXC_INT_IPI_2:
+		if (cpu_has_guestctl2)
+			set_c0_guestctl2(irq);
+		else
+			set_gc0_cause(irq);
+		break;
+
+	default:
+		break;
+	}
+
+	clear_bit(priority, &vcpu->arch.pending_exceptions);
+	return 1;
+}
+
+static int kvm_vz_irq_clear_cb(struct kvm_vcpu *vcpu, unsigned int priority,
+			       u32 cause)
+{
+	u32 irq = (priority < MIPS_EXC_MAX) ?
+		kvm_priority_to_irq[priority] : 0;
+
+	switch (priority) {
+	case MIPS_EXC_INT_TIMER:
+		/*
+		 * Explicitly clear irq associated with Cause.IP[IPTI]
+		 * if GuestCtl2 virtual interrupt register not
+		 * supported or if not using GuestCtl2 Hardware Clear.
+		 */
+		if (cpu_has_guestctl2) {
+			if (!(read_c0_guestctl2() & (irq << 14)))
+				clear_c0_guestctl2(irq);
+		} else {
+			clear_gc0_cause(irq);
+		}
+		break;
+
+	case MIPS_EXC_INT_IO_1:
+	case MIPS_EXC_INT_IO_2:
+	case MIPS_EXC_INT_IPI_1:
+	case MIPS_EXC_INT_IPI_2:
+		/* Clear GuestCtl2.VIP irq if not using Hardware Clear */
+		if (cpu_has_guestctl2) {
+			if (!(read_c0_guestctl2() & (irq << 14)))
+				clear_c0_guestctl2(irq);
+		} else {
+			clear_gc0_cause(irq);
+		}
+		break;
+
+	default:
+		break;
+	}
+
+	clear_bit(priority, &vcpu->arch.pending_exceptions_clr);
+	return 1;
+}
+
+/*
+ * VZ guest timer handling.
+ */
+
+/**
+ * kvm_vz_should_use_htimer() - Find whether to use the VZ hard guest timer.
+ * @vcpu:	Virtual CPU.
+ *
+ * Returns:	true if the VZ GTOffset & real guest CP0_Count should be used
+ *		instead of software emulation of guest timer.
+ *		false otherwise.
+ */
+static bool kvm_vz_should_use_htimer(struct kvm_vcpu *vcpu)
+{
+	if (kvm_mips_count_disabled(vcpu))
+		return false;
+
+	/* Chosen frequency must match real frequency */
+	if (mips_hpt_frequency != vcpu->arch.count_hz)
+		return false;
+
+	/* We don't support a CP0_GTOffset with fewer bits than CP0_Count */
+	if (current_cpu_data.gtoffset_mask != 0xffffffff)
+		return false;
+
+	return true;
+}
+
+/**
+ * _kvm_vz_restore_stimer() - Restore soft timer state.
+ * @vcpu:	Virtual CPU.
+ * @compare:	CP0_Compare register value, restored by caller.
+ * @cause:	CP0_Cause register to restore.
+ *
+ * Restore VZ state relating to the soft timer. The hard timer can be enabled
+ * later.
+ */
+static void _kvm_vz_restore_stimer(struct kvm_vcpu *vcpu, u32 compare,
+				   u32 cause)
+{
+	/*
+	 * Avoid spurious counter interrupts by setting Guest CP0_Count to just
+	 * after Guest CP0_Compare.
+	 */
+	write_c0_gtoffset(compare - read_c0_count());
+
+	back_to_back_c0_hazard();
+	write_gc0_cause(cause);
+}
+
+/**
+ * _kvm_vz_restore_htimer() - Restore hard timer state.
+ * @vcpu:	Virtual CPU.
+ * @compare:	CP0_Compare register value, restored by caller.
+ * @cause:	CP0_Cause register to restore.
+ *
+ * Restore hard timer Guest.Count & Guest.Cause taking care to preserve the
+ * value of Guest.CP0_Cause.TI while restoring Guest.CP0_Cause.
+ */
+static void _kvm_vz_restore_htimer(struct kvm_vcpu *vcpu,
+				   u32 compare, u32 cause)
+{
+	u32 start_count, after_count;
+	unsigned long flags;
+
+	/*
+	 * Freeze the soft-timer and sync the guest CP0_Count with it. We do
+	 * this with interrupts disabled to avoid latency.
+	 */
+	local_irq_save(flags);
+	kvm_mips_freeze_hrtimer(vcpu, &start_count);
+	write_c0_gtoffset(start_count - read_c0_count());
+	local_irq_restore(flags);
+
+	/* restore guest CP0_Cause, as TI may already be set */
+	back_to_back_c0_hazard();
+	write_gc0_cause(cause);
+
+	/*
+	 * The above sequence isn't atomic and would result in lost timer
+	 * interrupts if we're not careful. Detect if a timer interrupt is due
+	 * and assert it.
+	 */
+	back_to_back_c0_hazard();
+	after_count = read_gc0_count();
+	if (after_count - start_count > compare - start_count - 1)
+		kvm_vz_queue_irq(vcpu, MIPS_EXC_INT_TIMER);
+}
+
+/**
+ * kvm_vz_restore_timer() - Restore timer state.
+ * @vcpu:	Virtual CPU.
+ *
+ * Restore soft timer state from saved context.
+ */
+static void kvm_vz_restore_timer(struct kvm_vcpu *vcpu)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+	u32 cause, compare;
+
+	compare = kvm_read_sw_gc0_compare(cop0);
+	cause = kvm_read_sw_gc0_cause(cop0);
+
+	write_gc0_compare(compare);
+	_kvm_vz_restore_stimer(vcpu, compare, cause);
+}
+
+/**
+ * kvm_vz_acquire_htimer() - Switch to hard timer state.
+ * @vcpu:	Virtual CPU.
+ *
+ * Restore hard timer state on top of existing soft timer state if possible.
+ *
+ * Since hard timer won't remain active over preemption, preemption should be
+ * disabled by the caller.
+ */
+void kvm_vz_acquire_htimer(struct kvm_vcpu *vcpu)
+{
+	u32 gctl0;
+
+	gctl0 = read_c0_guestctl0();
+	if (!(gctl0 & MIPS_GCTL0_GT) && kvm_vz_should_use_htimer(vcpu)) {
+		/* enable guest access to hard timer */
+		write_c0_guestctl0(gctl0 | MIPS_GCTL0_GT);
+
+		_kvm_vz_restore_htimer(vcpu, read_gc0_compare(),
+				       read_gc0_cause());
+	}
+}
+
+/**
+ * _kvm_vz_save_htimer() - Switch to software emulation of guest timer.
+ * @vcpu:	Virtual CPU.
+ * @out_compare: Pointer to write compare value to.
+ * @out_cause:	Pointer to write cause value to.
+ *
+ * Save VZ guest timer state and switch to software emulation of guest CP0
+ * timer. The hard timer must already be in use, so preemption should be
+ * disabled.
+ */
+static void _kvm_vz_save_htimer(struct kvm_vcpu *vcpu,
+				u32 *out_compare, u32 *out_cause)
+{
+	u32 cause, compare, before_count, end_count;
+	ktime_t before_time;
+
+	compare = read_gc0_compare();
+	*out_compare = compare;
+
+	before_time = ktime_get();
+
+	/*
+	 * Record the CP0_Count *prior* to saving CP0_Cause, so we have a time
+	 * at which no pending timer interrupt is missing.
+	 */
+	before_count = read_gc0_count();
+	back_to_back_c0_hazard();
+	cause = read_gc0_cause();
+	*out_cause = cause;
+
+	/*
+	 * Record a final CP0_Count which we will transfer to the soft-timer.
+	 * This is recorded *after* saving CP0_Cause, so we don't get any timer
+	 * interrupts from just after the final CP0_Count point.
+	 */
+	back_to_back_c0_hazard();
+	end_count = read_gc0_count();
+
+	/*
+	 * The above sequence isn't atomic, so we could miss a timer interrupt
+	 * between reading CP0_Cause and end_count. Detect and record any timer
+	 * interrupt due between before_count and end_count.
+	 */
+	if (end_count - before_count > compare - before_count - 1)
+		kvm_vz_queue_irq(vcpu, MIPS_EXC_INT_TIMER);
+
+	/*
+	 * Restore soft-timer, ignoring a small amount of negative drift due to
+	 * delay between freeze_hrtimer and setting CP0_GTOffset.
+	 */
+	kvm_mips_restore_hrtimer(vcpu, before_time, end_count, -0x10000);
+}
+
+/**
+ * kvm_vz_save_timer() - Save guest timer state.
+ * @vcpu:	Virtual CPU.
+ *
+ * Save VZ guest timer state and switch to soft guest timer if hard timer was in
+ * use.
+ */
+static void kvm_vz_save_timer(struct kvm_vcpu *vcpu)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+	u32 gctl0, compare, cause;
+
+	gctl0 = read_c0_guestctl0();
+	if (gctl0 & MIPS_GCTL0_GT) {
+		/* disable guest use of hard timer */
+		write_c0_guestctl0(gctl0 & ~MIPS_GCTL0_GT);
+
+		/* save hard timer state */
+		_kvm_vz_save_htimer(vcpu, &compare, &cause);
+	} else {
+		compare = read_gc0_compare();
+		cause = read_gc0_cause();
+	}
+
+	/* save timer-related state to VCPU context */
+	kvm_write_sw_gc0_cause(cop0, cause);
+	kvm_write_sw_gc0_compare(cop0, compare);
+}
+
+/**
+ * kvm_vz_lose_htimer() - Ensure hard guest timer is not in use.
+ * @vcpu:	Virtual CPU.
+ *
+ * Transfers the state of the hard guest timer to the soft guest timer, leaving
+ * guest state intact so it can continue to be used with the soft timer.
+ */
+void kvm_vz_lose_htimer(struct kvm_vcpu *vcpu)
+{
+	u32 gctl0, compare, cause;
+
+	preempt_disable();
+	gctl0 = read_c0_guestctl0();
+	if (gctl0 & MIPS_GCTL0_GT) {
+		/* disable guest use of timer */
+		write_c0_guestctl0(gctl0 & ~MIPS_GCTL0_GT);
+
+		/* switch to soft timer */
+		_kvm_vz_save_htimer(vcpu, &compare, &cause);
+
+		/* leave soft timer in usable state */
+		_kvm_vz_restore_stimer(vcpu, compare, cause);
+	}
+	preempt_enable();
+}
+
+/**
+ * is_eva_access() - Find whether an instruction is an EVA memory accessor.
+ * @inst:	32-bit instruction encoding.
+ *
+ * Finds whether @inst encodes an EVA memory access instruction, which would
+ * indicate that emulation of it should access the user mode address space
+ * instead of the kernel mode address space. This matters for MUSUK segments
+ * which are TLB mapped for user mode but unmapped for kernel mode.
+ *
+ * Returns:	Whether @inst encodes an EVA accessor instruction.
+ */
+static bool is_eva_access(union mips_instruction inst)
+{
+	if (inst.spec3_format.opcode != spec3_op)
+		return false;
+
+	switch (inst.spec3_format.func) {
+	case lwle_op:
+	case lwre_op:
+	case cachee_op:
+	case sbe_op:
+	case she_op:
+	case sce_op:
+	case swe_op:
+	case swle_op:
+	case swre_op:
+	case prefe_op:
+	case lbue_op:
+	case lhue_op:
+	case lbe_op:
+	case lhe_op:
+	case lle_op:
+	case lwe_op:
+		return true;
+	default:
+		return false;
+	}
+}
+
+/**
+ * is_eva_am_mapped() - Find whether an access mode is mapped.
+ * @vcpu:	KVM VCPU state.
+ * @am:		3-bit encoded access mode.
+ * @eu:		Segment becomes unmapped and uncached when Status.ERL=1.
+ *
+ * Decode @am to find whether it encodes a mapped segment for the current VCPU
+ * state. Where necessary @eu and the actual instruction causing the fault are
+ * taken into account to make the decision.
+ *
+ * Returns:	Whether the VCPU faulted on a TLB mapped address.
+ */
+static bool is_eva_am_mapped(struct kvm_vcpu *vcpu, unsigned int am, bool eu)
+{
+	u32 am_lookup;
+	int err;
+
+	/*
+	 * Interpret access control mode. We assume address errors will already
+	 * have been caught by the guest, leaving us with:
+	 *      AM      UM  SM  KM  31..24 23..16
+	 * UK    0 000          Unm   0      0
+	 * MK    1 001          TLB   1
+	 * MSK   2 010      TLB TLB   1
+	 * MUSK  3 011  TLB TLB TLB   1
+	 * MUSUK 4 100  TLB TLB Unm   0      1
+	 * USK   5 101      Unm Unm   0      0
+	 * -     6 110                0      0
+	 * UUSK  7 111  Unm Unm Unm   0      0
+	 *
+	 * We shift a magic value by AM across the sign bit to find if always
+	 * TLB mapped, and if not shift by 8 again to find if it depends on KM.
+	 */
+	am_lookup = 0x70080000 << am;
+	if ((s32)am_lookup < 0) {
+		/*
+		 * MK, MSK, MUSK
+		 * Always TLB mapped, unless SegCtl.EU && ERL
+		 */
+		if (!eu || !(read_gc0_status() & ST0_ERL))
+			return true;
+	} else {
+		am_lookup <<= 8;
+		if ((s32)am_lookup < 0) {
+			union mips_instruction inst;
+			unsigned int status;
+			u32 *opc;
+
+			/*
+			 * MUSUK
+			 * TLB mapped if not in kernel mode
+			 */
+			status = read_gc0_status();
+			if (!(status & (ST0_EXL | ST0_ERL)) &&
+			    (status & ST0_KSU))
+				return true;
+			/*
+			 * EVA access instructions in kernel
+			 * mode access user address space.
+			 */
+			opc = (u32 *)vcpu->arch.pc;
+			if (vcpu->arch.host_cp0_cause & CAUSEF_BD)
+				opc += 1;
+			err = kvm_get_badinstr(opc, vcpu, &inst.word);
+			if (!err && is_eva_access(inst))
+				return true;
+		}
+	}
+
+	return false;
+}
+
+/**
+ * kvm_vz_gva_to_gpa() - Convert valid GVA to GPA.
+ * @vcpu:	KVM VCPU state.
+ * @gva:	Guest virtual address to convert.
+ * @gpa:	Output guest physical address.
+ *
+ * Convert a guest virtual address (GVA) which is valid according to the guest
+ * context, to a guest physical address (GPA).
+ *
+ * Returns:	0 on success.
+ *		-errno on failure.
+ */
+static int kvm_vz_gva_to_gpa(struct kvm_vcpu *vcpu, unsigned long gva,
+			     unsigned long *gpa)
+{
+	u32 gva32 = gva;
+	unsigned long segctl;
+
+	if ((long)gva == (s32)gva32) {
+		/* Handle canonical 32-bit virtual address */
+		if (cpu_guest_has_segments) {
+			unsigned long mask, pa;
+
+			switch (gva32 >> 29) {
+			case 0:
+			case 1: /* CFG5 (1GB) */
+				segctl = read_gc0_segctl2() >> 16;
+				mask = (unsigned long)0xfc0000000ull;
+				break;
+			case 2:
+			case 3: /* CFG4 (1GB) */
+				segctl = read_gc0_segctl2();
+				mask = (unsigned long)0xfc0000000ull;
+				break;
+			case 4: /* CFG3 (512MB) */
+				segctl = read_gc0_segctl1() >> 16;
+				mask = (unsigned long)0xfe0000000ull;
+				break;
+			case 5: /* CFG2 (512MB) */
+				segctl = read_gc0_segctl1();
+				mask = (unsigned long)0xfe0000000ull;
+				break;
+			case 6: /* CFG1 (512MB) */
+				segctl = read_gc0_segctl0() >> 16;
+				mask = (unsigned long)0xfe0000000ull;
+				break;
+			case 7: /* CFG0 (512MB) */
+				segctl = read_gc0_segctl0();
+				mask = (unsigned long)0xfe0000000ull;
+				break;
+			default:
+				/*
+				 * GCC 4.9 isn't smart enough to figure out that
+				 * segctl and mask are always initialised.
+				 */
+				unreachable();
+			}
+
+			if (is_eva_am_mapped(vcpu, (segctl >> 4) & 0x7,
+					     segctl & 0x0008))
+				goto tlb_mapped;
+
+			/* Unmapped, find guest physical address */
+			pa = (segctl << 20) & mask;
+			pa |= gva32 & ~mask;
+			*gpa = pa;
+			return 0;
+		} else if ((s32)gva32 < (s32)0xc0000000) {
+			/* legacy unmapped KSeg0 or KSeg1 */
+			*gpa = gva32 & 0x1fffffff;
+			return 0;
+		}
+#ifdef CONFIG_64BIT
+	} else if ((gva & 0xc000000000000000) == 0x8000000000000000) {
+		/* XKPHYS */
+		if (cpu_guest_has_segments) {
+			/*
+			 * Each of the 8 regions can be overridden by SegCtl2.XR
+			 * to use SegCtl1.XAM.
+			 */
+			segctl = read_gc0_segctl2();
+			if (segctl & (1ull << (56 + ((gva >> 59) & 0x7)))) {
+				segctl = read_gc0_segctl1();
+				if (is_eva_am_mapped(vcpu, (segctl >> 59) & 0x7,
+						     0))
+					goto tlb_mapped;
+			}
+
+		}
+		/*
+		 * Traditionally fully unmapped.
+		 * Bits 61:59 specify the CCA, which we can just mask off here.
+		 * Bits 58:PABITS should be zero, but we shouldn't have got here
+		 * if it wasn't.
+		 */
+		*gpa = gva & 0x07ffffffffffffff;
+		return 0;
+#endif
+	}
+
+tlb_mapped:
+	return kvm_vz_guest_tlb_lookup(vcpu, gva, gpa);
+}
+
+/**
+ * kvm_vz_badvaddr_to_gpa() - Convert GVA BadVAddr from root exception to GPA.
+ * @vcpu:	KVM VCPU state.
+ * @badvaddr:	Root BadVAddr.
+ * @gpa:	Output guest physical address.
+ *
+ * VZ implementations are permitted to report guest virtual addresses (GVA) in
+ * BadVAddr on a root exception during guest execution, instead of the more
+ * convenient guest physical addresses (GPA). When we get a GVA, this function
+ * converts it to a GPA, taking into account guest segmentation and guest TLB
+ * state.
+ *
+ * Returns:	0 on success.
+ *		-errno on failure.
+ */
+static int kvm_vz_badvaddr_to_gpa(struct kvm_vcpu *vcpu, unsigned long badvaddr,
+				  unsigned long *gpa)
+{
+	unsigned int gexccode = (vcpu->arch.host_cp0_guestctl0 &
+				 MIPS_GCTL0_GEXC) >> MIPS_GCTL0_GEXC_SHIFT;
+
+	/* If BadVAddr is GPA, then all is well in the world */
+	if (likely(gexccode == MIPS_GCTL0_GEXC_GPA)) {
+		*gpa = badvaddr;
+		return 0;
+	}
+
+	/* Otherwise we'd expect it to be GVA ... */
+	if (WARN(gexccode != MIPS_GCTL0_GEXC_GVA,
+		 "Unexpected gexccode %#x\n", gexccode))
+		return -EINVAL;
+
+	/* ... and we need to perform the GVA->GPA translation in software */
+	return kvm_vz_gva_to_gpa(vcpu, badvaddr, gpa);
+}
+
+static int kvm_trap_vz_no_handler(struct kvm_vcpu *vcpu)
+{
+	u32 *opc = (u32 *) vcpu->arch.pc;
+	u32 cause = vcpu->arch.host_cp0_cause;
+	u32 exccode = (cause & CAUSEF_EXCCODE) >> CAUSEB_EXCCODE;
+	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
+	u32 inst = 0;
+
+	/*
+	 *  Fetch the instruction.
+	 */
+	if (cause & CAUSEF_BD)
+		opc += 1;
+	kvm_get_badinstr(opc, vcpu, &inst);
+
+	kvm_err("Exception Code: %d not handled @ PC: %p, inst: 0x%08x BadVaddr: %#lx Status: %#x\n",
+		exccode, opc, inst, badvaddr,
+		read_gc0_status());
+	kvm_arch_vcpu_dump_regs(vcpu);
+	vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+	return RESUME_HOST;
+}
+
+static unsigned long mips_process_maar(unsigned int op, unsigned long val)
+{
+	/* Mask off unused bits */
+	unsigned long mask = 0xfffff000 | MIPS_MAAR_S | MIPS_MAAR_VL;
+
+	if (read_gc0_pagegrain() & PG_ELPA)
+		mask |= 0x00ffffff00000000ull;
+	if (cpu_guest_has_mvh)
+		mask |= MIPS_MAAR_VH;
+
+	/* Set or clear VH */
+	if (op == mtc_op) {
+		/* clear VH */
+		val &= ~MIPS_MAAR_VH;
+	} else if (op == dmtc_op) {
+		/* set VH to match VL */
+		val &= ~MIPS_MAAR_VH;
+		if (val & MIPS_MAAR_VL)
+			val |= MIPS_MAAR_VH;
+	}
+
+	return val & mask;
+}
+
+static void kvm_write_maari(struct kvm_vcpu *vcpu, unsigned long val)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+
+	val &= MIPS_MAARI_INDEX;
+	if (val == MIPS_MAARI_INDEX)
+		kvm_write_sw_gc0_maari(cop0, ARRAY_SIZE(vcpu->arch.maar) - 1);
+	else if (val < ARRAY_SIZE(vcpu->arch.maar))
+		kvm_write_sw_gc0_maari(cop0, val);
+}
+
+static enum emulation_result kvm_vz_gpsi_cop0(union mips_instruction inst,
+					      u32 *opc, u32 cause,
+					      struct kvm_vcpu *vcpu)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+	enum emulation_result er = EMULATE_DONE;
+	u32 rt, rd, sel;
+	unsigned long curr_pc;
+	unsigned long val;
+
+	/*
+	 * Update PC and hold onto current PC in case there is
+	 * an error and we want to rollback the PC
+	 */
+	curr_pc = vcpu->arch.pc;
+	er = update_pc(vcpu, cause);
+	if (er == EMULATE_FAIL)
+		return er;
+
+	if (inst.co_format.co) {
+		switch (inst.co_format.func) {
+		case wait_op:
+			er = kvm_mips_emul_wait(vcpu);
+			break;
+		default:
+			er = EMULATE_FAIL;
+		}
+	} else {
+		rt = inst.c0r_format.rt;
+		rd = inst.c0r_format.rd;
+		sel = inst.c0r_format.sel;
+
+		switch (inst.c0r_format.rs) {
+		case dmfc_op:
+		case mfc_op:
+#ifdef CONFIG_KVM_MIPS_DEBUG_COP0_COUNTERS
+			cop0->stat[rd][sel]++;
+#endif
+			if (rd == MIPS_CP0_COUNT &&
+			    sel == 0) {			/* Count */
+				val = kvm_mips_read_count(vcpu);
+			} else if (rd == MIPS_CP0_COMPARE &&
+				   sel == 0) {		/* Compare */
+				val = read_gc0_compare();
+			} else if (rd == MIPS_CP0_LLADDR &&
+				   sel == 0) {		/* LLAddr */
+				if (cpu_guest_has_rw_llb)
+					val = read_gc0_lladdr() &
+						MIPS_LLADDR_LLB;
+				else
+					val = 0;
+			} else if (rd == MIPS_CP0_LLADDR &&
+				   sel == 1 &&		/* MAAR */
+				   cpu_guest_has_maar &&
+				   !cpu_guest_has_dyn_maar) {
+				/* MAARI must be in range */
+				BUG_ON(kvm_read_sw_gc0_maari(cop0) >=
+						ARRAY_SIZE(vcpu->arch.maar));
+				val = vcpu->arch.maar[
+					kvm_read_sw_gc0_maari(cop0)];
+			} else if ((rd == MIPS_CP0_PRID &&
+				    (sel == 0 ||	/* PRid */
+				     sel == 2 ||	/* CDMMBase */
+				     sel == 3)) ||	/* CMGCRBase */
+				   (rd == MIPS_CP0_STATUS &&
+				    (sel == 2 ||	/* SRSCtl */
+				     sel == 3)) ||	/* SRSMap */
+				   (rd == MIPS_CP0_CONFIG &&
+				    (sel == 6 ||	/* Config6 */
+				     sel == 7)) ||	/* Config7 */
+				   (rd == MIPS_CP0_LLADDR &&
+				    (sel == 2) &&	/* MAARI */
+				    cpu_guest_has_maar &&
+				    !cpu_guest_has_dyn_maar) ||
+				   (rd == MIPS_CP0_ERRCTL &&
+				    (sel == 0))) {	/* ErrCtl */
+				val = cop0->reg[rd][sel];
+#ifdef CONFIG_CPU_LOONGSON64
+			} else if (rd == MIPS_CP0_DIAG &&
+				   (sel == 0)) {	/* Diag */
+				val = cop0->reg[rd][sel];
+#endif
+			} else {
+				val = 0;
+				er = EMULATE_FAIL;
+			}
+
+			if (er != EMULATE_FAIL) {
+				/* Sign extend */
+				if (inst.c0r_format.rs == mfc_op)
+					val = (int)val;
+				vcpu->arch.gprs[rt] = val;
+			}
+
+			trace_kvm_hwr(vcpu, (inst.c0r_format.rs == mfc_op) ?
+					KVM_TRACE_MFC0 : KVM_TRACE_DMFC0,
+				      KVM_TRACE_COP0(rd, sel), val);
+			break;
+
+		case dmtc_op:
+		case mtc_op:
+#ifdef CONFIG_KVM_MIPS_DEBUG_COP0_COUNTERS
+			cop0->stat[rd][sel]++;
+#endif
+			val = vcpu->arch.gprs[rt];
+			trace_kvm_hwr(vcpu, (inst.c0r_format.rs == mtc_op) ?
+					KVM_TRACE_MTC0 : KVM_TRACE_DMTC0,
+				      KVM_TRACE_COP0(rd, sel), val);
+
+			if (rd == MIPS_CP0_COUNT &&
+			    sel == 0) {			/* Count */
+				kvm_vz_lose_htimer(vcpu);
+				kvm_mips_write_count(vcpu, vcpu->arch.gprs[rt]);
+			} else if (rd == MIPS_CP0_COMPARE &&
+				   sel == 0) {		/* Compare */
+				kvm_mips_write_compare(vcpu,
+						       vcpu->arch.gprs[rt],
+						       true);
+			} else if (rd == MIPS_CP0_LLADDR &&
+				   sel == 0) {		/* LLAddr */
+				/*
+				 * P5600 generates GPSI on guest MTC0 LLAddr.
+				 * Only allow the guest to clear LLB.
+				 */
+				if (cpu_guest_has_rw_llb &&
+				    !(val & MIPS_LLADDR_LLB))
+					write_gc0_lladdr(0);
+			} else if (rd == MIPS_CP0_LLADDR &&
+				   sel == 1 &&		/* MAAR */
+				   cpu_guest_has_maar &&
+				   !cpu_guest_has_dyn_maar) {
+				val = mips_process_maar(inst.c0r_format.rs,
+							val);
+
+				/* MAARI must be in range */
+				BUG_ON(kvm_read_sw_gc0_maari(cop0) >=
+						ARRAY_SIZE(vcpu->arch.maar));
+				vcpu->arch.maar[kvm_read_sw_gc0_maari(cop0)] =
+									val;
+			} else if (rd == MIPS_CP0_LLADDR &&
+				   (sel == 2) &&	/* MAARI */
+				   cpu_guest_has_maar &&
+				   !cpu_guest_has_dyn_maar) {
+				kvm_write_maari(vcpu, val);
+			} else if (rd == MIPS_CP0_CONFIG &&
+				   (sel == 6)) {
+				cop0->reg[rd][sel] = (int)val;
+			} else if (rd == MIPS_CP0_ERRCTL &&
+				   (sel == 0)) {	/* ErrCtl */
+				/* ignore the written value */
+#ifdef CONFIG_CPU_LOONGSON64
+			} else if (rd == MIPS_CP0_DIAG &&
+				   (sel == 0)) {	/* Diag */
+				unsigned long flags;
+
+				local_irq_save(flags);
+				if (val & LOONGSON_DIAG_BTB) {
+					/* Flush BTB */
+					set_c0_diag(LOONGSON_DIAG_BTB);
+				}
+				if (val & LOONGSON_DIAG_ITLB) {
+					/* Flush ITLB */
+					set_c0_diag(LOONGSON_DIAG_ITLB);
+				}
+				if (val & LOONGSON_DIAG_DTLB) {
+					/* Flush DTLB */
+					set_c0_diag(LOONGSON_DIAG_DTLB);
+				}
+				if (val & LOONGSON_DIAG_VTLB) {
+					/* Flush VTLB */
+					kvm_loongson_clear_guest_vtlb();
+				}
+				if (val & LOONGSON_DIAG_FTLB) {
+					/* Flush FTLB */
+					kvm_loongson_clear_guest_ftlb();
+				}
+				local_irq_restore(flags);
+#endif
+			} else {
+				er = EMULATE_FAIL;
+			}
+			break;
+
+		default:
+			er = EMULATE_FAIL;
+			break;
+		}
+	}
+	/* Rollback PC only if emulation was unsuccessful */
+	if (er == EMULATE_FAIL) {
+		kvm_err("[%#lx]%s: unsupported cop0 instruction 0x%08x\n",
+			curr_pc, __func__, inst.word);
+
+		vcpu->arch.pc = curr_pc;
+	}
+
+	return er;
+}
+
+static enum emulation_result kvm_vz_gpsi_cache(union mips_instruction inst,
+					       u32 *opc, u32 cause,
+					       struct kvm_vcpu *vcpu)
+{
+	enum emulation_result er = EMULATE_DONE;
+	u32 cache, op_inst, op, base;
+	s16 offset;
+	struct kvm_vcpu_arch *arch = &vcpu->arch;
+	unsigned long va, curr_pc;
+
+	/*
+	 * Update PC and hold onto current PC in case there is
+	 * an error and we want to rollback the PC
+	 */
+	curr_pc = vcpu->arch.pc;
+	er = update_pc(vcpu, cause);
+	if (er == EMULATE_FAIL)
+		return er;
+
+	base = inst.i_format.rs;
+	op_inst = inst.i_format.rt;
+	if (cpu_has_mips_r6)
+		offset = inst.spec3_format.simmediate;
+	else
+		offset = inst.i_format.simmediate;
+	cache = op_inst & CacheOp_Cache;
+	op = op_inst & CacheOp_Op;
+
+	va = arch->gprs[base] + offset;
+
+	kvm_debug("CACHE (cache: %#x, op: %#x, base[%d]: %#lx, offset: %#x\n",
+		  cache, op, base, arch->gprs[base], offset);
+
+	/* Secondary or tirtiary cache ops ignored */
+	if (cache != Cache_I && cache != Cache_D)
+		return EMULATE_DONE;
+
+	switch (op_inst) {
+	case Index_Invalidate_I:
+		flush_icache_line_indexed(va);
+		return EMULATE_DONE;
+	case Index_Writeback_Inv_D:
+		flush_dcache_line_indexed(va);
+		return EMULATE_DONE;
+	case Hit_Invalidate_I:
+	case Hit_Invalidate_D:
+	case Hit_Writeback_Inv_D:
+		if (boot_cpu_type() == CPU_CAVIUM_OCTEON3) {
+			/* We can just flush entire icache */
+			local_flush_icache_range(0, 0);
+			return EMULATE_DONE;
+		}
+
+		/* So far, other platforms support guest hit cache ops */
+		break;
+	default:
+		break;
+	}
+
+	kvm_err("@ %#lx/%#lx CACHE (cache: %#x, op: %#x, base[%d]: %#lx, offset: %#x\n",
+		curr_pc, vcpu->arch.gprs[31], cache, op, base, arch->gprs[base],
+		offset);
+	/* Rollback PC */
+	vcpu->arch.pc = curr_pc;
+
+	return EMULATE_FAIL;
+}
+
+#ifdef CONFIG_CPU_LOONGSON64
+static enum emulation_result kvm_vz_gpsi_lwc2(union mips_instruction inst,
+					      u32 *opc, u32 cause,
+					      struct kvm_vcpu *vcpu)
+{
+	unsigned int rs, rd;
+	unsigned int hostcfg;
+	unsigned long curr_pc;
+	enum emulation_result er = EMULATE_DONE;
+
+	/*
+	 * Update PC and hold onto current PC in case there is
+	 * an error and we want to rollback the PC
+	 */
+	curr_pc = vcpu->arch.pc;
+	er = update_pc(vcpu, cause);
+	if (er == EMULATE_FAIL)
+		return er;
+
+	rs = inst.loongson3_lscsr_format.rs;
+	rd = inst.loongson3_lscsr_format.rd;
+	switch (inst.loongson3_lscsr_format.fr) {
+	case 0x8:  /* Read CPUCFG */
+		++vcpu->stat.vz_cpucfg_exits;
+		hostcfg = read_cpucfg(vcpu->arch.gprs[rs]);
+
+		switch (vcpu->arch.gprs[rs]) {
+		case LOONGSON_CFG0:
+			vcpu->arch.gprs[rd] = 0x14c000;
+			break;
+		case LOONGSON_CFG1:
+			hostcfg &= (LOONGSON_CFG1_FP | LOONGSON_CFG1_MMI |
+				    LOONGSON_CFG1_MSA1 | LOONGSON_CFG1_MSA2 |
+				    LOONGSON_CFG1_SFBP);
+			vcpu->arch.gprs[rd] = hostcfg;
+			break;
+		case LOONGSON_CFG2:
+			hostcfg &= (LOONGSON_CFG2_LEXT1 | LOONGSON_CFG2_LEXT2 |
+				    LOONGSON_CFG2_LEXT3 | LOONGSON_CFG2_LSPW);
+			vcpu->arch.gprs[rd] = hostcfg;
+			break;
+		case LOONGSON_CFG3:
+			vcpu->arch.gprs[rd] = hostcfg;
+			break;
+		default:
+			/* Don't export any other advanced features to guest */
+			vcpu->arch.gprs[rd] = 0;
+			break;
+		}
+		break;
+
+	default:
+		kvm_err("lwc2 emulate not impl %d rs %lx @%lx\n",
+			inst.loongson3_lscsr_format.fr, vcpu->arch.gprs[rs], curr_pc);
+		er = EMULATE_FAIL;
+		break;
+	}
+
+	/* Rollback PC only if emulation was unsuccessful */
+	if (er == EMULATE_FAIL) {
+		kvm_err("[%#lx]%s: unsupported lwc2 instruction 0x%08x 0x%08x\n",
+			curr_pc, __func__, inst.word, inst.loongson3_lscsr_format.fr);
+
+		vcpu->arch.pc = curr_pc;
+	}
+
+	return er;
+}
+#endif
+
+static enum emulation_result kvm_trap_vz_handle_gpsi(u32 cause, u32 *opc,
+						     struct kvm_vcpu *vcpu)
+{
+	enum emulation_result er = EMULATE_DONE;
+	struct kvm_vcpu_arch *arch = &vcpu->arch;
+	union mips_instruction inst;
+	int rd, rt, sel;
+	int err;
+
+	/*
+	 *  Fetch the instruction.
+	 */
+	if (cause & CAUSEF_BD)
+		opc += 1;
+	err = kvm_get_badinstr(opc, vcpu, &inst.word);
+	if (err)
+		return EMULATE_FAIL;
+
+	switch (inst.r_format.opcode) {
+	case cop0_op:
+		er = kvm_vz_gpsi_cop0(inst, opc, cause, vcpu);
+		break;
+#ifndef CONFIG_CPU_MIPSR6
+	case cache_op:
+		trace_kvm_exit(vcpu, KVM_TRACE_EXIT_CACHE);
+		er = kvm_vz_gpsi_cache(inst, opc, cause, vcpu);
+		break;
+#endif
+#ifdef CONFIG_CPU_LOONGSON64
+	case lwc2_op:
+		er = kvm_vz_gpsi_lwc2(inst, opc, cause, vcpu);
+		break;
+#endif
+	case spec3_op:
+		switch (inst.spec3_format.func) {
+#ifdef CONFIG_CPU_MIPSR6
+		case cache6_op:
+			trace_kvm_exit(vcpu, KVM_TRACE_EXIT_CACHE);
+			er = kvm_vz_gpsi_cache(inst, opc, cause, vcpu);
+			break;
+#endif
+		case rdhwr_op:
+			if (inst.r_format.rs || (inst.r_format.re >> 3))
+				goto unknown;
+
+			rd = inst.r_format.rd;
+			rt = inst.r_format.rt;
+			sel = inst.r_format.re & 0x7;
+
+			switch (rd) {
+			case MIPS_HWR_CC:	/* Read count register */
+				arch->gprs[rt] =
+					(long)(int)kvm_mips_read_count(vcpu);
+				break;
+			default:
+				trace_kvm_hwr(vcpu, KVM_TRACE_RDHWR,
+					      KVM_TRACE_HWR(rd, sel), 0);
+				goto unknown;
+			}
+
+			trace_kvm_hwr(vcpu, KVM_TRACE_RDHWR,
+				      KVM_TRACE_HWR(rd, sel), arch->gprs[rt]);
+
+			er = update_pc(vcpu, cause);
+			break;
+		default:
+			goto unknown;
+		}
+		break;
+unknown:
+
+	default:
+		kvm_err("GPSI exception not supported (%p/%#x)\n",
+				opc, inst.word);
+		kvm_arch_vcpu_dump_regs(vcpu);
+		er = EMULATE_FAIL;
+		break;
+	}
+
+	return er;
+}
+
+static enum emulation_result kvm_trap_vz_handle_gsfc(u32 cause, u32 *opc,
+						     struct kvm_vcpu *vcpu)
+{
+	enum emulation_result er = EMULATE_DONE;
+	struct kvm_vcpu_arch *arch = &vcpu->arch;
+	union mips_instruction inst;
+	int err;
+
+	/*
+	 *  Fetch the instruction.
+	 */
+	if (cause & CAUSEF_BD)
+		opc += 1;
+	err = kvm_get_badinstr(opc, vcpu, &inst.word);
+	if (err)
+		return EMULATE_FAIL;
+
+	/* complete MTC0 on behalf of guest and advance EPC */
+	if (inst.c0r_format.opcode == cop0_op &&
+	    inst.c0r_format.rs == mtc_op &&
+	    inst.c0r_format.z == 0) {
+		int rt = inst.c0r_format.rt;
+		int rd = inst.c0r_format.rd;
+		int sel = inst.c0r_format.sel;
+		unsigned int val = arch->gprs[rt];
+		unsigned int old_val, change;
+
+		trace_kvm_hwr(vcpu, KVM_TRACE_MTC0, KVM_TRACE_COP0(rd, sel),
+			      val);
+
+		if ((rd == MIPS_CP0_STATUS) && (sel == 0)) {
+			/* FR bit should read as zero if no FPU */
+			if (!kvm_mips_guest_has_fpu(&vcpu->arch))
+				val &= ~(ST0_CU1 | ST0_FR);
+
+			/*
+			 * Also don't allow FR to be set if host doesn't support
+			 * it.
+			 */
+			if (!(boot_cpu_data.fpu_id & MIPS_FPIR_F64))
+				val &= ~ST0_FR;
+
+			old_val = read_gc0_status();
+			change = val ^ old_val;
+
+			if (change & ST0_FR) {
+				/*
+				 * FPU and Vector register state is made
+				 * UNPREDICTABLE by a change of FR, so don't
+				 * even bother saving it.
+				 */
+				kvm_drop_fpu(vcpu);
+			}
+
+			/*
+			 * If MSA state is already live, it is undefined how it
+			 * interacts with FR=0 FPU state, and we don't want to
+			 * hit reserved instruction exceptions trying to save
+			 * the MSA state later when CU=1 && FR=1, so play it
+			 * safe and save it first.
+			 */
+			if (change & ST0_CU1 && !(val & ST0_FR) &&
+			    vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA)
+				kvm_lose_fpu(vcpu);
+
+			write_gc0_status(val);
+		} else if ((rd == MIPS_CP0_CAUSE) && (sel == 0)) {
+			u32 old_cause = read_gc0_cause();
+			u32 change = old_cause ^ val;
+
+			/* DC bit enabling/disabling timer? */
+			if (change & CAUSEF_DC) {
+				if (val & CAUSEF_DC) {
+					kvm_vz_lose_htimer(vcpu);
+					kvm_mips_count_disable_cause(vcpu);
+				} else {
+					kvm_mips_count_enable_cause(vcpu);
+				}
+			}
+
+			/* Only certain bits are RW to the guest */
+			change &= (CAUSEF_DC | CAUSEF_IV | CAUSEF_WP |
+				   CAUSEF_IP0 | CAUSEF_IP1);
+
+			/* WP can only be cleared */
+			change &= ~CAUSEF_WP | old_cause;
+
+			write_gc0_cause(old_cause ^ change);
+		} else if ((rd == MIPS_CP0_STATUS) && (sel == 1)) { /* IntCtl */
+			write_gc0_intctl(val);
+		} else if ((rd == MIPS_CP0_CONFIG) && (sel == 5)) {
+			old_val = read_gc0_config5();
+			change = val ^ old_val;
+			/* Handle changes in FPU/MSA modes */
+			preempt_disable();
+
+			/*
+			 * Propagate FRE changes immediately if the FPU
+			 * context is already loaded.
+			 */
+			if (change & MIPS_CONF5_FRE &&
+			    vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU)
+				change_c0_config5(MIPS_CONF5_FRE, val);
+
+			preempt_enable();
+
+			val = old_val ^
+				(change & kvm_vz_config5_guest_wrmask(vcpu));
+			write_gc0_config5(val);
+		} else {
+			kvm_err("Handle GSFC, unsupported field change @ %p: %#x\n",
+			    opc, inst.word);
+			er = EMULATE_FAIL;
+		}
+
+		if (er != EMULATE_FAIL)
+			er = update_pc(vcpu, cause);
+	} else {
+		kvm_err("Handle GSFC, unrecognized instruction @ %p: %#x\n",
+			opc, inst.word);
+		er = EMULATE_FAIL;
+	}
+
+	return er;
+}
+
+static enum emulation_result kvm_trap_vz_handle_ghfc(u32 cause, u32 *opc,
+						     struct kvm_vcpu *vcpu)
+{
+	/*
+	 * Presumably this is due to MC (guest mode change), so lets trace some
+	 * relevant info.
+	 */
+	trace_kvm_guest_mode_change(vcpu);
+
+	return EMULATE_DONE;
+}
+
+static enum emulation_result kvm_trap_vz_handle_hc(u32 cause, u32 *opc,
+						   struct kvm_vcpu *vcpu)
+{
+	enum emulation_result er;
+	union mips_instruction inst;
+	unsigned long curr_pc;
+	int err;
+
+	if (cause & CAUSEF_BD)
+		opc += 1;
+	err = kvm_get_badinstr(opc, vcpu, &inst.word);
+	if (err)
+		return EMULATE_FAIL;
+
+	/*
+	 * Update PC and hold onto current PC in case there is
+	 * an error and we want to rollback the PC
+	 */
+	curr_pc = vcpu->arch.pc;
+	er = update_pc(vcpu, cause);
+	if (er == EMULATE_FAIL)
+		return er;
+
+	er = kvm_mips_emul_hypcall(vcpu, inst);
+	if (er == EMULATE_FAIL)
+		vcpu->arch.pc = curr_pc;
+
+	return er;
+}
+
+static enum emulation_result kvm_trap_vz_no_handler_guest_exit(u32 gexccode,
+							u32 cause,
+							u32 *opc,
+							struct kvm_vcpu *vcpu)
+{
+	u32 inst;
+
+	/*
+	 *  Fetch the instruction.
+	 */
+	if (cause & CAUSEF_BD)
+		opc += 1;
+	kvm_get_badinstr(opc, vcpu, &inst);
+
+	kvm_err("Guest Exception Code: %d not yet handled @ PC: %p, inst: 0x%08x  Status: %#x\n",
+		gexccode, opc, inst, read_gc0_status());
+
+	return EMULATE_FAIL;
+}
+
+static int kvm_trap_vz_handle_guest_exit(struct kvm_vcpu *vcpu)
+{
+	u32 *opc = (u32 *) vcpu->arch.pc;
+	u32 cause = vcpu->arch.host_cp0_cause;
+	enum emulation_result er = EMULATE_DONE;
+	u32 gexccode = (vcpu->arch.host_cp0_guestctl0 &
+			MIPS_GCTL0_GEXC) >> MIPS_GCTL0_GEXC_SHIFT;
+	int ret = RESUME_GUEST;
+
+	trace_kvm_exit(vcpu, KVM_TRACE_EXIT_GEXCCODE_BASE + gexccode);
+	switch (gexccode) {
+	case MIPS_GCTL0_GEXC_GPSI:
+		++vcpu->stat.vz_gpsi_exits;
+		er = kvm_trap_vz_handle_gpsi(cause, opc, vcpu);
+		break;
+	case MIPS_GCTL0_GEXC_GSFC:
+		++vcpu->stat.vz_gsfc_exits;
+		er = kvm_trap_vz_handle_gsfc(cause, opc, vcpu);
+		break;
+	case MIPS_GCTL0_GEXC_HC:
+		++vcpu->stat.vz_hc_exits;
+		er = kvm_trap_vz_handle_hc(cause, opc, vcpu);
+		break;
+	case MIPS_GCTL0_GEXC_GRR:
+		++vcpu->stat.vz_grr_exits;
+		er = kvm_trap_vz_no_handler_guest_exit(gexccode, cause, opc,
+						       vcpu);
+		break;
+	case MIPS_GCTL0_GEXC_GVA:
+		++vcpu->stat.vz_gva_exits;
+		er = kvm_trap_vz_no_handler_guest_exit(gexccode, cause, opc,
+						       vcpu);
+		break;
+	case MIPS_GCTL0_GEXC_GHFC:
+		++vcpu->stat.vz_ghfc_exits;
+		er = kvm_trap_vz_handle_ghfc(cause, opc, vcpu);
+		break;
+	case MIPS_GCTL0_GEXC_GPA:
+		++vcpu->stat.vz_gpa_exits;
+		er = kvm_trap_vz_no_handler_guest_exit(gexccode, cause, opc,
+						       vcpu);
+		break;
+	default:
+		++vcpu->stat.vz_resvd_exits;
+		er = kvm_trap_vz_no_handler_guest_exit(gexccode, cause, opc,
+						       vcpu);
+		break;
+
+	}
+
+	if (er == EMULATE_DONE) {
+		ret = RESUME_GUEST;
+	} else if (er == EMULATE_HYPERCALL) {
+		ret = kvm_mips_handle_hypcall(vcpu);
+	} else {
+		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+		ret = RESUME_HOST;
+	}
+	return ret;
+}
+
+/**
+ * kvm_trap_vz_handle_cop_unusable() - Guest used unusable coprocessor.
+ * @vcpu:	Virtual CPU context.
+ *
+ * Handle when the guest attempts to use a coprocessor which hasn't been allowed
+ * by the root context.
+ *
+ * Return: value indicating whether to resume the host or the guest
+ * 	   (RESUME_HOST or RESUME_GUEST)
+ */
+static int kvm_trap_vz_handle_cop_unusable(struct kvm_vcpu *vcpu)
+{
+	u32 cause = vcpu->arch.host_cp0_cause;
+	enum emulation_result er = EMULATE_FAIL;
+	int ret = RESUME_GUEST;
+
+	if (((cause & CAUSEF_CE) >> CAUSEB_CE) == 1) {
+		/*
+		 * If guest FPU not present, the FPU operation should have been
+		 * treated as a reserved instruction!
+		 * If FPU already in use, we shouldn't get this at all.
+		 */
+		if (WARN_ON(!kvm_mips_guest_has_fpu(&vcpu->arch) ||
+			    vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU)) {
+			preempt_enable();
+			return EMULATE_FAIL;
+		}
+
+		kvm_own_fpu(vcpu);
+		er = EMULATE_DONE;
+	}
+	/* other coprocessors not handled */
+
+	switch (er) {
+	case EMULATE_DONE:
+		ret = RESUME_GUEST;
+		break;
+
+	case EMULATE_FAIL:
+		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+		ret = RESUME_HOST;
+		break;
+
+	default:
+		BUG();
+	}
+	return ret;
+}
+
+/**
+ * kvm_trap_vz_handle_msa_disabled() - Guest used MSA while disabled in root.
+ * @vcpu:	Virtual CPU context.
+ *
+ * Handle when the guest attempts to use MSA when it is disabled in the root
+ * context.
+ *
+ * Return: value indicating whether to resume the host or the guest
+ * 	   (RESUME_HOST or RESUME_GUEST)
+ */
+static int kvm_trap_vz_handle_msa_disabled(struct kvm_vcpu *vcpu)
+{
+	/*
+	 * If MSA not present or not exposed to guest or FR=0, the MSA operation
+	 * should have been treated as a reserved instruction!
+	 * Same if CU1=1, FR=0.
+	 * If MSA already in use, we shouldn't get this at all.
+	 */
+	if (!kvm_mips_guest_has_msa(&vcpu->arch) ||
+	    (read_gc0_status() & (ST0_CU1 | ST0_FR)) == ST0_CU1 ||
+	    !(read_gc0_config5() & MIPS_CONF5_MSAEN) ||
+	    vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
+		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+		return RESUME_HOST;
+	}
+
+	kvm_own_msa(vcpu);
+
+	return RESUME_GUEST;
+}
+
+static int kvm_trap_vz_handle_tlb_ld_miss(struct kvm_vcpu *vcpu)
+{
+	struct kvm_run *run = vcpu->run;
+	u32 *opc = (u32 *) vcpu->arch.pc;
+	u32 cause = vcpu->arch.host_cp0_cause;
+	ulong badvaddr = vcpu->arch.host_cp0_badvaddr;
+	union mips_instruction inst;
+	enum emulation_result er = EMULATE_DONE;
+	int err, ret = RESUME_GUEST;
+
+	if (kvm_mips_handle_vz_root_tlb_fault(badvaddr, vcpu, false)) {
+		/* A code fetch fault doesn't count as an MMIO */
+		if (kvm_is_ifetch_fault(&vcpu->arch)) {
+			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+			return RESUME_HOST;
+		}
+
+		/* Fetch the instruction */
+		if (cause & CAUSEF_BD)
+			opc += 1;
+		err = kvm_get_badinstr(opc, vcpu, &inst.word);
+		if (err) {
+			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+			return RESUME_HOST;
+		}
+
+		/* Treat as MMIO */
+		er = kvm_mips_emulate_load(inst, cause, vcpu);
+		if (er == EMULATE_FAIL) {
+			kvm_err("Guest Emulate Load from MMIO space failed: PC: %p, BadVaddr: %#lx\n",
+				opc, badvaddr);
+			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+		}
+	}
+
+	if (er == EMULATE_DONE) {
+		ret = RESUME_GUEST;
+	} else if (er == EMULATE_DO_MMIO) {
+		run->exit_reason = KVM_EXIT_MMIO;
+		ret = RESUME_HOST;
+	} else {
+		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+		ret = RESUME_HOST;
+	}
+	return ret;
+}
+
+static int kvm_trap_vz_handle_tlb_st_miss(struct kvm_vcpu *vcpu)
+{
+	struct kvm_run *run = vcpu->run;
+	u32 *opc = (u32 *) vcpu->arch.pc;
+	u32 cause = vcpu->arch.host_cp0_cause;
+	ulong badvaddr = vcpu->arch.host_cp0_badvaddr;
+	union mips_instruction inst;
+	enum emulation_result er = EMULATE_DONE;
+	int err;
+	int ret = RESUME_GUEST;
+
+	/* Just try the access again if we couldn't do the translation */
+	if (kvm_vz_badvaddr_to_gpa(vcpu, badvaddr, &badvaddr))
+		return RESUME_GUEST;
+	vcpu->arch.host_cp0_badvaddr = badvaddr;
+
+	if (kvm_mips_handle_vz_root_tlb_fault(badvaddr, vcpu, true)) {
+		/* Fetch the instruction */
+		if (cause & CAUSEF_BD)
+			opc += 1;
+		err = kvm_get_badinstr(opc, vcpu, &inst.word);
+		if (err) {
+			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+			return RESUME_HOST;
+		}
+
+		/* Treat as MMIO */
+		er = kvm_mips_emulate_store(inst, cause, vcpu);
+		if (er == EMULATE_FAIL) {
+			kvm_err("Guest Emulate Store to MMIO space failed: PC: %p, BadVaddr: %#lx\n",
+				opc, badvaddr);
+			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+		}
+	}
+
+	if (er == EMULATE_DONE) {
+		ret = RESUME_GUEST;
+	} else if (er == EMULATE_DO_MMIO) {
+		run->exit_reason = KVM_EXIT_MMIO;
+		ret = RESUME_HOST;
+	} else {
+		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+		ret = RESUME_HOST;
+	}
+	return ret;
+}
+
+static u64 kvm_vz_get_one_regs[] = {
+	KVM_REG_MIPS_CP0_INDEX,
+	KVM_REG_MIPS_CP0_ENTRYLO0,
+	KVM_REG_MIPS_CP0_ENTRYLO1,
+	KVM_REG_MIPS_CP0_CONTEXT,
+	KVM_REG_MIPS_CP0_PAGEMASK,
+	KVM_REG_MIPS_CP0_PAGEGRAIN,
+	KVM_REG_MIPS_CP0_WIRED,
+	KVM_REG_MIPS_CP0_HWRENA,
+	KVM_REG_MIPS_CP0_BADVADDR,
+	KVM_REG_MIPS_CP0_COUNT,
+	KVM_REG_MIPS_CP0_ENTRYHI,
+	KVM_REG_MIPS_CP0_COMPARE,
+	KVM_REG_MIPS_CP0_STATUS,
+	KVM_REG_MIPS_CP0_INTCTL,
+	KVM_REG_MIPS_CP0_CAUSE,
+	KVM_REG_MIPS_CP0_EPC,
+	KVM_REG_MIPS_CP0_PRID,
+	KVM_REG_MIPS_CP0_EBASE,
+	KVM_REG_MIPS_CP0_CONFIG,
+	KVM_REG_MIPS_CP0_CONFIG1,
+	KVM_REG_MIPS_CP0_CONFIG2,
+	KVM_REG_MIPS_CP0_CONFIG3,
+	KVM_REG_MIPS_CP0_CONFIG4,
+	KVM_REG_MIPS_CP0_CONFIG5,
+	KVM_REG_MIPS_CP0_CONFIG6,
+#ifdef CONFIG_64BIT
+	KVM_REG_MIPS_CP0_XCONTEXT,
+#endif
+	KVM_REG_MIPS_CP0_ERROREPC,
+
+	KVM_REG_MIPS_COUNT_CTL,
+	KVM_REG_MIPS_COUNT_RESUME,
+	KVM_REG_MIPS_COUNT_HZ,
+};
+
+static u64 kvm_vz_get_one_regs_contextconfig[] = {
+	KVM_REG_MIPS_CP0_CONTEXTCONFIG,
+#ifdef CONFIG_64BIT
+	KVM_REG_MIPS_CP0_XCONTEXTCONFIG,
+#endif
+};
+
+static u64 kvm_vz_get_one_regs_segments[] = {
+	KVM_REG_MIPS_CP0_SEGCTL0,
+	KVM_REG_MIPS_CP0_SEGCTL1,
+	KVM_REG_MIPS_CP0_SEGCTL2,
+};
+
+static u64 kvm_vz_get_one_regs_htw[] = {
+	KVM_REG_MIPS_CP0_PWBASE,
+	KVM_REG_MIPS_CP0_PWFIELD,
+	KVM_REG_MIPS_CP0_PWSIZE,
+	KVM_REG_MIPS_CP0_PWCTL,
+};
+
+static u64 kvm_vz_get_one_regs_kscratch[] = {
+	KVM_REG_MIPS_CP0_KSCRATCH1,
+	KVM_REG_MIPS_CP0_KSCRATCH2,
+	KVM_REG_MIPS_CP0_KSCRATCH3,
+	KVM_REG_MIPS_CP0_KSCRATCH4,
+	KVM_REG_MIPS_CP0_KSCRATCH5,
+	KVM_REG_MIPS_CP0_KSCRATCH6,
+};
+
+static unsigned long kvm_vz_num_regs(struct kvm_vcpu *vcpu)
+{
+	unsigned long ret;
+
+	ret = ARRAY_SIZE(kvm_vz_get_one_regs);
+	if (cpu_guest_has_userlocal)
+		++ret;
+	if (cpu_guest_has_badinstr)
+		++ret;
+	if (cpu_guest_has_badinstrp)
+		++ret;
+	if (cpu_guest_has_contextconfig)
+		ret += ARRAY_SIZE(kvm_vz_get_one_regs_contextconfig);
+	if (cpu_guest_has_segments)
+		ret += ARRAY_SIZE(kvm_vz_get_one_regs_segments);
+	if (cpu_guest_has_htw || cpu_guest_has_ldpte)
+		ret += ARRAY_SIZE(kvm_vz_get_one_regs_htw);
+	if (cpu_guest_has_maar && !cpu_guest_has_dyn_maar)
+		ret += 1 + ARRAY_SIZE(vcpu->arch.maar);
+	ret += __arch_hweight8(cpu_data[0].guest.kscratch_mask);
+
+	return ret;
+}
+
+static int kvm_vz_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices)
+{
+	u64 index;
+	unsigned int i;
+
+	if (copy_to_user(indices, kvm_vz_get_one_regs,
+			 sizeof(kvm_vz_get_one_regs)))
+		return -EFAULT;
+	indices += ARRAY_SIZE(kvm_vz_get_one_regs);
+
+	if (cpu_guest_has_userlocal) {
+		index = KVM_REG_MIPS_CP0_USERLOCAL;
+		if (copy_to_user(indices, &index, sizeof(index)))
+			return -EFAULT;
+		++indices;
+	}
+	if (cpu_guest_has_badinstr) {
+		index = KVM_REG_MIPS_CP0_BADINSTR;
+		if (copy_to_user(indices, &index, sizeof(index)))
+			return -EFAULT;
+		++indices;
+	}
+	if (cpu_guest_has_badinstrp) {
+		index = KVM_REG_MIPS_CP0_BADINSTRP;
+		if (copy_to_user(indices, &index, sizeof(index)))
+			return -EFAULT;
+		++indices;
+	}
+	if (cpu_guest_has_contextconfig) {
+		if (copy_to_user(indices, kvm_vz_get_one_regs_contextconfig,
+				 sizeof(kvm_vz_get_one_regs_contextconfig)))
+			return -EFAULT;
+		indices += ARRAY_SIZE(kvm_vz_get_one_regs_contextconfig);
+	}
+	if (cpu_guest_has_segments) {
+		if (copy_to_user(indices, kvm_vz_get_one_regs_segments,
+				 sizeof(kvm_vz_get_one_regs_segments)))
+			return -EFAULT;
+		indices += ARRAY_SIZE(kvm_vz_get_one_regs_segments);
+	}
+	if (cpu_guest_has_htw || cpu_guest_has_ldpte) {
+		if (copy_to_user(indices, kvm_vz_get_one_regs_htw,
+				 sizeof(kvm_vz_get_one_regs_htw)))
+			return -EFAULT;
+		indices += ARRAY_SIZE(kvm_vz_get_one_regs_htw);
+	}
+	if (cpu_guest_has_maar && !cpu_guest_has_dyn_maar) {
+		for (i = 0; i < ARRAY_SIZE(vcpu->arch.maar); ++i) {
+			index = KVM_REG_MIPS_CP0_MAAR(i);
+			if (copy_to_user(indices, &index, sizeof(index)))
+				return -EFAULT;
+			++indices;
+		}
+
+		index = KVM_REG_MIPS_CP0_MAARI;
+		if (copy_to_user(indices, &index, sizeof(index)))
+			return -EFAULT;
+		++indices;
+	}
+	for (i = 0; i < 6; ++i) {
+		if (!cpu_guest_has_kscr(i + 2))
+			continue;
+
+		if (copy_to_user(indices, &kvm_vz_get_one_regs_kscratch[i],
+				 sizeof(kvm_vz_get_one_regs_kscratch[i])))
+			return -EFAULT;
+		++indices;
+	}
+
+	return 0;
+}
+
+static inline s64 entrylo_kvm_to_user(unsigned long v)
+{
+	s64 mask, ret = v;
+
+	if (BITS_PER_LONG == 32) {
+		/*
+		 * KVM API exposes 64-bit version of the register, so move the
+		 * RI/XI bits up into place.
+		 */
+		mask = MIPS_ENTRYLO_RI | MIPS_ENTRYLO_XI;
+		ret &= ~mask;
+		ret |= ((s64)v & mask) << 32;
+	}
+	return ret;
+}
+
+static inline unsigned long entrylo_user_to_kvm(s64 v)
+{
+	unsigned long mask, ret = v;
+
+	if (BITS_PER_LONG == 32) {
+		/*
+		 * KVM API exposes 64-bit versiono of the register, so move the
+		 * RI/XI bits down into place.
+		 */
+		mask = MIPS_ENTRYLO_RI | MIPS_ENTRYLO_XI;
+		ret &= ~mask;
+		ret |= (v >> 32) & mask;
+	}
+	return ret;
+}
+
+static int kvm_vz_get_one_reg(struct kvm_vcpu *vcpu,
+			      const struct kvm_one_reg *reg,
+			      s64 *v)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+	unsigned int idx;
+
+	switch (reg->id) {
+	case KVM_REG_MIPS_CP0_INDEX:
+		*v = (long)read_gc0_index();
+		break;
+	case KVM_REG_MIPS_CP0_ENTRYLO0:
+		*v = entrylo_kvm_to_user(read_gc0_entrylo0());
+		break;
+	case KVM_REG_MIPS_CP0_ENTRYLO1:
+		*v = entrylo_kvm_to_user(read_gc0_entrylo1());
+		break;
+	case KVM_REG_MIPS_CP0_CONTEXT:
+		*v = (long)read_gc0_context();
+		break;
+	case KVM_REG_MIPS_CP0_CONTEXTCONFIG:
+		if (!cpu_guest_has_contextconfig)
+			return -EINVAL;
+		*v = read_gc0_contextconfig();
+		break;
+	case KVM_REG_MIPS_CP0_USERLOCAL:
+		if (!cpu_guest_has_userlocal)
+			return -EINVAL;
+		*v = read_gc0_userlocal();
+		break;
+#ifdef CONFIG_64BIT
+	case KVM_REG_MIPS_CP0_XCONTEXTCONFIG:
+		if (!cpu_guest_has_contextconfig)
+			return -EINVAL;
+		*v = read_gc0_xcontextconfig();
+		break;
+#endif
+	case KVM_REG_MIPS_CP0_PAGEMASK:
+		*v = (long)read_gc0_pagemask();
+		break;
+	case KVM_REG_MIPS_CP0_PAGEGRAIN:
+		*v = (long)read_gc0_pagegrain();
+		break;
+	case KVM_REG_MIPS_CP0_SEGCTL0:
+		if (!cpu_guest_has_segments)
+			return -EINVAL;
+		*v = read_gc0_segctl0();
+		break;
+	case KVM_REG_MIPS_CP0_SEGCTL1:
+		if (!cpu_guest_has_segments)
+			return -EINVAL;
+		*v = read_gc0_segctl1();
+		break;
+	case KVM_REG_MIPS_CP0_SEGCTL2:
+		if (!cpu_guest_has_segments)
+			return -EINVAL;
+		*v = read_gc0_segctl2();
+		break;
+	case KVM_REG_MIPS_CP0_PWBASE:
+		if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
+			return -EINVAL;
+		*v = read_gc0_pwbase();
+		break;
+	case KVM_REG_MIPS_CP0_PWFIELD:
+		if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
+			return -EINVAL;
+		*v = read_gc0_pwfield();
+		break;
+	case KVM_REG_MIPS_CP0_PWSIZE:
+		if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
+			return -EINVAL;
+		*v = read_gc0_pwsize();
+		break;
+	case KVM_REG_MIPS_CP0_WIRED:
+		*v = (long)read_gc0_wired();
+		break;
+	case KVM_REG_MIPS_CP0_PWCTL:
+		if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
+			return -EINVAL;
+		*v = read_gc0_pwctl();
+		break;
+	case KVM_REG_MIPS_CP0_HWRENA:
+		*v = (long)read_gc0_hwrena();
+		break;
+	case KVM_REG_MIPS_CP0_BADVADDR:
+		*v = (long)read_gc0_badvaddr();
+		break;
+	case KVM_REG_MIPS_CP0_BADINSTR:
+		if (!cpu_guest_has_badinstr)
+			return -EINVAL;
+		*v = read_gc0_badinstr();
+		break;
+	case KVM_REG_MIPS_CP0_BADINSTRP:
+		if (!cpu_guest_has_badinstrp)
+			return -EINVAL;
+		*v = read_gc0_badinstrp();
+		break;
+	case KVM_REG_MIPS_CP0_COUNT:
+		*v = kvm_mips_read_count(vcpu);
+		break;
+	case KVM_REG_MIPS_CP0_ENTRYHI:
+		*v = (long)read_gc0_entryhi();
+		break;
+	case KVM_REG_MIPS_CP0_COMPARE:
+		*v = (long)read_gc0_compare();
+		break;
+	case KVM_REG_MIPS_CP0_STATUS:
+		*v = (long)read_gc0_status();
+		break;
+	case KVM_REG_MIPS_CP0_INTCTL:
+		*v = read_gc0_intctl();
+		break;
+	case KVM_REG_MIPS_CP0_CAUSE:
+		*v = (long)read_gc0_cause();
+		break;
+	case KVM_REG_MIPS_CP0_EPC:
+		*v = (long)read_gc0_epc();
+		break;
+	case KVM_REG_MIPS_CP0_PRID:
+		switch (boot_cpu_type()) {
+		case CPU_CAVIUM_OCTEON3:
+			/* Octeon III has a read-only guest.PRid */
+			*v = read_gc0_prid();
+			break;
+		default:
+			*v = (long)kvm_read_c0_guest_prid(cop0);
+			break;
+		}
+		break;
+	case KVM_REG_MIPS_CP0_EBASE:
+		*v = kvm_vz_read_gc0_ebase();
+		break;
+	case KVM_REG_MIPS_CP0_CONFIG:
+		*v = read_gc0_config();
+		break;
+	case KVM_REG_MIPS_CP0_CONFIG1:
+		if (!cpu_guest_has_conf1)
+			return -EINVAL;
+		*v = read_gc0_config1();
+		break;
+	case KVM_REG_MIPS_CP0_CONFIG2:
+		if (!cpu_guest_has_conf2)
+			return -EINVAL;
+		*v = read_gc0_config2();
+		break;
+	case KVM_REG_MIPS_CP0_CONFIG3:
+		if (!cpu_guest_has_conf3)
+			return -EINVAL;
+		*v = read_gc0_config3();
+		break;
+	case KVM_REG_MIPS_CP0_CONFIG4:
+		if (!cpu_guest_has_conf4)
+			return -EINVAL;
+		*v = read_gc0_config4();
+		break;
+	case KVM_REG_MIPS_CP0_CONFIG5:
+		if (!cpu_guest_has_conf5)
+			return -EINVAL;
+		*v = read_gc0_config5();
+		break;
+	case KVM_REG_MIPS_CP0_CONFIG6:
+		*v = kvm_read_sw_gc0_config6(cop0);
+		break;
+	case KVM_REG_MIPS_CP0_MAAR(0) ... KVM_REG_MIPS_CP0_MAAR(0x3f):
+		if (!cpu_guest_has_maar || cpu_guest_has_dyn_maar)
+			return -EINVAL;
+		idx = reg->id - KVM_REG_MIPS_CP0_MAAR(0);
+		if (idx >= ARRAY_SIZE(vcpu->arch.maar))
+			return -EINVAL;
+		*v = vcpu->arch.maar[idx];
+		break;
+	case KVM_REG_MIPS_CP0_MAARI:
+		if (!cpu_guest_has_maar || cpu_guest_has_dyn_maar)
+			return -EINVAL;
+		*v = kvm_read_sw_gc0_maari(&vcpu->arch.cop0);
+		break;
+#ifdef CONFIG_64BIT
+	case KVM_REG_MIPS_CP0_XCONTEXT:
+		*v = read_gc0_xcontext();
+		break;
+#endif
+	case KVM_REG_MIPS_CP0_ERROREPC:
+		*v = (long)read_gc0_errorepc();
+		break;
+	case KVM_REG_MIPS_CP0_KSCRATCH1 ... KVM_REG_MIPS_CP0_KSCRATCH6:
+		idx = reg->id - KVM_REG_MIPS_CP0_KSCRATCH1 + 2;
+		if (!cpu_guest_has_kscr(idx))
+			return -EINVAL;
+		switch (idx) {
+		case 2:
+			*v = (long)read_gc0_kscratch1();
+			break;
+		case 3:
+			*v = (long)read_gc0_kscratch2();
+			break;
+		case 4:
+			*v = (long)read_gc0_kscratch3();
+			break;
+		case 5:
+			*v = (long)read_gc0_kscratch4();
+			break;
+		case 6:
+			*v = (long)read_gc0_kscratch5();
+			break;
+		case 7:
+			*v = (long)read_gc0_kscratch6();
+			break;
+		}
+		break;
+	case KVM_REG_MIPS_COUNT_CTL:
+		*v = vcpu->arch.count_ctl;
+		break;
+	case KVM_REG_MIPS_COUNT_RESUME:
+		*v = ktime_to_ns(vcpu->arch.count_resume);
+		break;
+	case KVM_REG_MIPS_COUNT_HZ:
+		*v = vcpu->arch.count_hz;
+		break;
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static int kvm_vz_set_one_reg(struct kvm_vcpu *vcpu,
+			      const struct kvm_one_reg *reg,
+			      s64 v)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+	unsigned int idx;
+	int ret = 0;
+	unsigned int cur, change;
+
+	switch (reg->id) {
+	case KVM_REG_MIPS_CP0_INDEX:
+		write_gc0_index(v);
+		break;
+	case KVM_REG_MIPS_CP0_ENTRYLO0:
+		write_gc0_entrylo0(entrylo_user_to_kvm(v));
+		break;
+	case KVM_REG_MIPS_CP0_ENTRYLO1:
+		write_gc0_entrylo1(entrylo_user_to_kvm(v));
+		break;
+	case KVM_REG_MIPS_CP0_CONTEXT:
+		write_gc0_context(v);
+		break;
+	case KVM_REG_MIPS_CP0_CONTEXTCONFIG:
+		if (!cpu_guest_has_contextconfig)
+			return -EINVAL;
+		write_gc0_contextconfig(v);
+		break;
+	case KVM_REG_MIPS_CP0_USERLOCAL:
+		if (!cpu_guest_has_userlocal)
+			return -EINVAL;
+		write_gc0_userlocal(v);
+		break;
+#ifdef CONFIG_64BIT
+	case KVM_REG_MIPS_CP0_XCONTEXTCONFIG:
+		if (!cpu_guest_has_contextconfig)
+			return -EINVAL;
+		write_gc0_xcontextconfig(v);
+		break;
+#endif
+	case KVM_REG_MIPS_CP0_PAGEMASK:
+		write_gc0_pagemask(v);
+		break;
+	case KVM_REG_MIPS_CP0_PAGEGRAIN:
+		write_gc0_pagegrain(v);
+		break;
+	case KVM_REG_MIPS_CP0_SEGCTL0:
+		if (!cpu_guest_has_segments)
+			return -EINVAL;
+		write_gc0_segctl0(v);
+		break;
+	case KVM_REG_MIPS_CP0_SEGCTL1:
+		if (!cpu_guest_has_segments)
+			return -EINVAL;
+		write_gc0_segctl1(v);
+		break;
+	case KVM_REG_MIPS_CP0_SEGCTL2:
+		if (!cpu_guest_has_segments)
+			return -EINVAL;
+		write_gc0_segctl2(v);
+		break;
+	case KVM_REG_MIPS_CP0_PWBASE:
+		if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
+			return -EINVAL;
+		write_gc0_pwbase(v);
+		break;
+	case KVM_REG_MIPS_CP0_PWFIELD:
+		if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
+			return -EINVAL;
+		write_gc0_pwfield(v);
+		break;
+	case KVM_REG_MIPS_CP0_PWSIZE:
+		if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
+			return -EINVAL;
+		write_gc0_pwsize(v);
+		break;
+	case KVM_REG_MIPS_CP0_WIRED:
+		change_gc0_wired(MIPSR6_WIRED_WIRED, v);
+		break;
+	case KVM_REG_MIPS_CP0_PWCTL:
+		if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
+			return -EINVAL;
+		write_gc0_pwctl(v);
+		break;
+	case KVM_REG_MIPS_CP0_HWRENA:
+		write_gc0_hwrena(v);
+		break;
+	case KVM_REG_MIPS_CP0_BADVADDR:
+		write_gc0_badvaddr(v);
+		break;
+	case KVM_REG_MIPS_CP0_BADINSTR:
+		if (!cpu_guest_has_badinstr)
+			return -EINVAL;
+		write_gc0_badinstr(v);
+		break;
+	case KVM_REG_MIPS_CP0_BADINSTRP:
+		if (!cpu_guest_has_badinstrp)
+			return -EINVAL;
+		write_gc0_badinstrp(v);
+		break;
+	case KVM_REG_MIPS_CP0_COUNT:
+		kvm_mips_write_count(vcpu, v);
+		break;
+	case KVM_REG_MIPS_CP0_ENTRYHI:
+		write_gc0_entryhi(v);
+		break;
+	case KVM_REG_MIPS_CP0_COMPARE:
+		kvm_mips_write_compare(vcpu, v, false);
+		break;
+	case KVM_REG_MIPS_CP0_STATUS:
+		write_gc0_status(v);
+		break;
+	case KVM_REG_MIPS_CP0_INTCTL:
+		write_gc0_intctl(v);
+		break;
+	case KVM_REG_MIPS_CP0_CAUSE:
+		/*
+		 * If the timer is stopped or started (DC bit) it must look
+		 * atomic with changes to the timer interrupt pending bit (TI).
+		 * A timer interrupt should not happen in between.
+		 */
+		if ((read_gc0_cause() ^ v) & CAUSEF_DC) {
+			if (v & CAUSEF_DC) {
+				/* disable timer first */
+				kvm_mips_count_disable_cause(vcpu);
+				change_gc0_cause((u32)~CAUSEF_DC, v);
+			} else {
+				/* enable timer last */
+				change_gc0_cause((u32)~CAUSEF_DC, v);
+				kvm_mips_count_enable_cause(vcpu);
+			}
+		} else {
+			write_gc0_cause(v);
+		}
+		break;
+	case KVM_REG_MIPS_CP0_EPC:
+		write_gc0_epc(v);
+		break;
+	case KVM_REG_MIPS_CP0_PRID:
+		switch (boot_cpu_type()) {
+		case CPU_CAVIUM_OCTEON3:
+			/* Octeon III has a guest.PRid, but its read-only */
+			break;
+		default:
+			kvm_write_c0_guest_prid(cop0, v);
+			break;
+		}
+		break;
+	case KVM_REG_MIPS_CP0_EBASE:
+		kvm_vz_write_gc0_ebase(v);
+		break;
+	case KVM_REG_MIPS_CP0_CONFIG:
+		cur = read_gc0_config();
+		change = (cur ^ v) & kvm_vz_config_user_wrmask(vcpu);
+		if (change) {
+			v = cur ^ change;
+			write_gc0_config(v);
+		}
+		break;
+	case KVM_REG_MIPS_CP0_CONFIG1:
+		if (!cpu_guest_has_conf1)
+			break;
+		cur = read_gc0_config1();
+		change = (cur ^ v) & kvm_vz_config1_user_wrmask(vcpu);
+		if (change) {
+			v = cur ^ change;
+			write_gc0_config1(v);
+		}
+		break;
+	case KVM_REG_MIPS_CP0_CONFIG2:
+		if (!cpu_guest_has_conf2)
+			break;
+		cur = read_gc0_config2();
+		change = (cur ^ v) & kvm_vz_config2_user_wrmask(vcpu);
+		if (change) {
+			v = cur ^ change;
+			write_gc0_config2(v);
+		}
+		break;
+	case KVM_REG_MIPS_CP0_CONFIG3:
+		if (!cpu_guest_has_conf3)
+			break;
+		cur = read_gc0_config3();
+		change = (cur ^ v) & kvm_vz_config3_user_wrmask(vcpu);
+		if (change) {
+			v = cur ^ change;
+			write_gc0_config3(v);
+		}
+		break;
+	case KVM_REG_MIPS_CP0_CONFIG4:
+		if (!cpu_guest_has_conf4)
+			break;
+		cur = read_gc0_config4();
+		change = (cur ^ v) & kvm_vz_config4_user_wrmask(vcpu);
+		if (change) {
+			v = cur ^ change;
+			write_gc0_config4(v);
+		}
+		break;
+	case KVM_REG_MIPS_CP0_CONFIG5:
+		if (!cpu_guest_has_conf5)
+			break;
+		cur = read_gc0_config5();
+		change = (cur ^ v) & kvm_vz_config5_user_wrmask(vcpu);
+		if (change) {
+			v = cur ^ change;
+			write_gc0_config5(v);
+		}
+		break;
+	case KVM_REG_MIPS_CP0_CONFIG6:
+		cur = kvm_read_sw_gc0_config6(cop0);
+		change = (cur ^ v) & kvm_vz_config6_user_wrmask(vcpu);
+		if (change) {
+			v = cur ^ change;
+			kvm_write_sw_gc0_config6(cop0, (int)v);
+		}
+		break;
+	case KVM_REG_MIPS_CP0_MAAR(0) ... KVM_REG_MIPS_CP0_MAAR(0x3f):
+		if (!cpu_guest_has_maar || cpu_guest_has_dyn_maar)
+			return -EINVAL;
+		idx = reg->id - KVM_REG_MIPS_CP0_MAAR(0);
+		if (idx >= ARRAY_SIZE(vcpu->arch.maar))
+			return -EINVAL;
+		vcpu->arch.maar[idx] = mips_process_maar(dmtc_op, v);
+		break;
+	case KVM_REG_MIPS_CP0_MAARI:
+		if (!cpu_guest_has_maar || cpu_guest_has_dyn_maar)
+			return -EINVAL;
+		kvm_write_maari(vcpu, v);
+		break;
+#ifdef CONFIG_64BIT
+	case KVM_REG_MIPS_CP0_XCONTEXT:
+		write_gc0_xcontext(v);
+		break;
+#endif
+	case KVM_REG_MIPS_CP0_ERROREPC:
+		write_gc0_errorepc(v);
+		break;
+	case KVM_REG_MIPS_CP0_KSCRATCH1 ... KVM_REG_MIPS_CP0_KSCRATCH6:
+		idx = reg->id - KVM_REG_MIPS_CP0_KSCRATCH1 + 2;
+		if (!cpu_guest_has_kscr(idx))
+			return -EINVAL;
+		switch (idx) {
+		case 2:
+			write_gc0_kscratch1(v);
+			break;
+		case 3:
+			write_gc0_kscratch2(v);
+			break;
+		case 4:
+			write_gc0_kscratch3(v);
+			break;
+		case 5:
+			write_gc0_kscratch4(v);
+			break;
+		case 6:
+			write_gc0_kscratch5(v);
+			break;
+		case 7:
+			write_gc0_kscratch6(v);
+			break;
+		}
+		break;
+	case KVM_REG_MIPS_COUNT_CTL:
+		ret = kvm_mips_set_count_ctl(vcpu, v);
+		break;
+	case KVM_REG_MIPS_COUNT_RESUME:
+		ret = kvm_mips_set_count_resume(vcpu, v);
+		break;
+	case KVM_REG_MIPS_COUNT_HZ:
+		ret = kvm_mips_set_count_hz(vcpu, v);
+		break;
+	default:
+		return -EINVAL;
+	}
+	return ret;
+}
+
+#define guestid_cache(cpu)	(cpu_data[cpu].guestid_cache)
+static void kvm_vz_get_new_guestid(unsigned long cpu, struct kvm_vcpu *vcpu)
+{
+	unsigned long guestid = guestid_cache(cpu);
+
+	if (!(++guestid & GUESTID_MASK)) {
+		if (cpu_has_vtag_icache)
+			flush_icache_all();
+
+		if (!guestid)		/* fix version if needed */
+			guestid = GUESTID_FIRST_VERSION;
+
+		++guestid;		/* guestid 0 reserved for root */
+
+		/* start new guestid cycle */
+		kvm_vz_local_flush_roottlb_all_guests();
+		kvm_vz_local_flush_guesttlb_all();
+	}
+
+	guestid_cache(cpu) = guestid;
+}
+
+/* Returns 1 if the guest TLB may be clobbered */
+static int kvm_vz_check_requests(struct kvm_vcpu *vcpu, int cpu)
+{
+	int ret = 0;
+	int i;
+
+	if (!kvm_request_pending(vcpu))
+		return 0;
+
+	if (kvm_check_request(KVM_REQ_TLB_FLUSH, vcpu)) {
+		if (cpu_has_guestid) {
+			/* Drop all GuestIDs for this VCPU */
+			for_each_possible_cpu(i)
+				vcpu->arch.vzguestid[i] = 0;
+			/* This will clobber guest TLB contents too */
+			ret = 1;
+		}
+		/*
+		 * For Root ASID Dealias (RAD) we don't do anything here, but we
+		 * still need the request to ensure we recheck asid_flush_mask.
+		 * We can still return 0 as only the root TLB will be affected
+		 * by a root ASID flush.
+		 */
+	}
+
+	return ret;
+}
+
+static void kvm_vz_vcpu_save_wired(struct kvm_vcpu *vcpu)
+{
+	unsigned int wired = read_gc0_wired();
+	struct kvm_mips_tlb *tlbs;
+	int i;
+
+	/* Expand the wired TLB array if necessary */
+	wired &= MIPSR6_WIRED_WIRED;
+	if (wired > vcpu->arch.wired_tlb_limit) {
+		tlbs = krealloc(vcpu->arch.wired_tlb, wired *
+				sizeof(*vcpu->arch.wired_tlb), GFP_ATOMIC);
+		if (WARN_ON(!tlbs)) {
+			/* Save whatever we can */
+			wired = vcpu->arch.wired_tlb_limit;
+		} else {
+			vcpu->arch.wired_tlb = tlbs;
+			vcpu->arch.wired_tlb_limit = wired;
+		}
+	}
+
+	if (wired)
+		/* Save wired entries from the guest TLB */
+		kvm_vz_save_guesttlb(vcpu->arch.wired_tlb, 0, wired);
+	/* Invalidate any dropped entries since last time */
+	for (i = wired; i < vcpu->arch.wired_tlb_used; ++i) {
+		vcpu->arch.wired_tlb[i].tlb_hi = UNIQUE_GUEST_ENTRYHI(i);
+		vcpu->arch.wired_tlb[i].tlb_lo[0] = 0;
+		vcpu->arch.wired_tlb[i].tlb_lo[1] = 0;
+		vcpu->arch.wired_tlb[i].tlb_mask = 0;
+	}
+	vcpu->arch.wired_tlb_used = wired;
+}
+
+static void kvm_vz_vcpu_load_wired(struct kvm_vcpu *vcpu)
+{
+	/* Load wired entries into the guest TLB */
+	if (vcpu->arch.wired_tlb)
+		kvm_vz_load_guesttlb(vcpu->arch.wired_tlb, 0,
+				     vcpu->arch.wired_tlb_used);
+}
+
+static void kvm_vz_vcpu_load_tlb(struct kvm_vcpu *vcpu, int cpu)
+{
+	struct kvm *kvm = vcpu->kvm;
+	struct mm_struct *gpa_mm = &kvm->arch.gpa_mm;
+	bool migrated;
+
+	/*
+	 * Are we entering guest context on a different CPU to last time?
+	 * If so, the VCPU's guest TLB state on this CPU may be stale.
+	 */
+	migrated = (vcpu->arch.last_exec_cpu != cpu);
+	vcpu->arch.last_exec_cpu = cpu;
+
+	/*
+	 * A vcpu's GuestID is set in GuestCtl1.ID when the vcpu is loaded and
+	 * remains set until another vcpu is loaded in.  As a rule GuestRID
+	 * remains zeroed when in root context unless the kernel is busy
+	 * manipulating guest tlb entries.
+	 */
+	if (cpu_has_guestid) {
+		/*
+		 * Check if our GuestID is of an older version and thus invalid.
+		 *
+		 * We also discard the stored GuestID if we've executed on
+		 * another CPU, as the guest mappings may have changed without
+		 * hypervisor knowledge.
+		 */
+		if (migrated ||
+		    (vcpu->arch.vzguestid[cpu] ^ guestid_cache(cpu)) &
+					GUESTID_VERSION_MASK) {
+			kvm_vz_get_new_guestid(cpu, vcpu);
+			vcpu->arch.vzguestid[cpu] = guestid_cache(cpu);
+			trace_kvm_guestid_change(vcpu,
+						 vcpu->arch.vzguestid[cpu]);
+		}
+
+		/* Restore GuestID */
+		change_c0_guestctl1(GUESTID_MASK, vcpu->arch.vzguestid[cpu]);
+	} else {
+		/*
+		 * The Guest TLB only stores a single guest's TLB state, so
+		 * flush it if another VCPU has executed on this CPU.
+		 *
+		 * We also flush if we've executed on another CPU, as the guest
+		 * mappings may have changed without hypervisor knowledge.
+		 */
+		if (migrated || last_exec_vcpu[cpu] != vcpu)
+			kvm_vz_local_flush_guesttlb_all();
+		last_exec_vcpu[cpu] = vcpu;
+
+		/*
+		 * Root ASID dealiases guest GPA mappings in the root TLB.
+		 * Allocate new root ASID if needed.
+		 */
+		if (cpumask_test_and_clear_cpu(cpu, &kvm->arch.asid_flush_mask))
+			get_new_mmu_context(gpa_mm);
+		else
+			check_mmu_context(gpa_mm);
+	}
+}
+
+static int kvm_vz_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+	bool migrated, all;
+
+	/*
+	 * Have we migrated to a different CPU?
+	 * If so, any old guest TLB state may be stale.
+	 */
+	migrated = (vcpu->arch.last_sched_cpu != cpu);
+
+	/*
+	 * Was this the last VCPU to run on this CPU?
+	 * If not, any old guest state from this VCPU will have been clobbered.
+	 */
+	all = migrated || (last_vcpu[cpu] != vcpu);
+	last_vcpu[cpu] = vcpu;
+
+	/*
+	 * Restore CP0_Wired unconditionally as we clear it after use, and
+	 * restore wired guest TLB entries (while in guest context).
+	 */
+	kvm_restore_gc0_wired(cop0);
+	if (current->flags & PF_VCPU) {
+		tlbw_use_hazard();
+		kvm_vz_vcpu_load_tlb(vcpu, cpu);
+		kvm_vz_vcpu_load_wired(vcpu);
+	}
+
+	/*
+	 * Restore timer state regardless, as e.g. Cause.TI can change over time
+	 * if left unmaintained.
+	 */
+	kvm_vz_restore_timer(vcpu);
+
+	/* Set MC bit if we want to trace guest mode changes */
+	if (kvm_trace_guest_mode_change)
+		set_c0_guestctl0(MIPS_GCTL0_MC);
+	else
+		clear_c0_guestctl0(MIPS_GCTL0_MC);
+
+	/* Don't bother restoring registers multiple times unless necessary */
+	if (!all)
+		return 0;
+
+	/*
+	 * Restore config registers first, as some implementations restrict
+	 * writes to other registers when the corresponding feature bits aren't
+	 * set. For example Status.CU1 cannot be set unless Config1.FP is set.
+	 */
+	kvm_restore_gc0_config(cop0);
+	if (cpu_guest_has_conf1)
+		kvm_restore_gc0_config1(cop0);
+	if (cpu_guest_has_conf2)
+		kvm_restore_gc0_config2(cop0);
+	if (cpu_guest_has_conf3)
+		kvm_restore_gc0_config3(cop0);
+	if (cpu_guest_has_conf4)
+		kvm_restore_gc0_config4(cop0);
+	if (cpu_guest_has_conf5)
+		kvm_restore_gc0_config5(cop0);
+	if (cpu_guest_has_conf6)
+		kvm_restore_gc0_config6(cop0);
+	if (cpu_guest_has_conf7)
+		kvm_restore_gc0_config7(cop0);
+
+	kvm_restore_gc0_index(cop0);
+	kvm_restore_gc0_entrylo0(cop0);
+	kvm_restore_gc0_entrylo1(cop0);
+	kvm_restore_gc0_context(cop0);
+	if (cpu_guest_has_contextconfig)
+		kvm_restore_gc0_contextconfig(cop0);
+#ifdef CONFIG_64BIT
+	kvm_restore_gc0_xcontext(cop0);
+	if (cpu_guest_has_contextconfig)
+		kvm_restore_gc0_xcontextconfig(cop0);
+#endif
+	kvm_restore_gc0_pagemask(cop0);
+	kvm_restore_gc0_pagegrain(cop0);
+	kvm_restore_gc0_hwrena(cop0);
+	kvm_restore_gc0_badvaddr(cop0);
+	kvm_restore_gc0_entryhi(cop0);
+	kvm_restore_gc0_status(cop0);
+	kvm_restore_gc0_intctl(cop0);
+	kvm_restore_gc0_epc(cop0);
+	kvm_vz_write_gc0_ebase(kvm_read_sw_gc0_ebase(cop0));
+	if (cpu_guest_has_userlocal)
+		kvm_restore_gc0_userlocal(cop0);
+
+	kvm_restore_gc0_errorepc(cop0);
+
+	/* restore KScratch registers if enabled in guest */
+	if (cpu_guest_has_conf4) {
+		if (cpu_guest_has_kscr(2))
+			kvm_restore_gc0_kscratch1(cop0);
+		if (cpu_guest_has_kscr(3))
+			kvm_restore_gc0_kscratch2(cop0);
+		if (cpu_guest_has_kscr(4))
+			kvm_restore_gc0_kscratch3(cop0);
+		if (cpu_guest_has_kscr(5))
+			kvm_restore_gc0_kscratch4(cop0);
+		if (cpu_guest_has_kscr(6))
+			kvm_restore_gc0_kscratch5(cop0);
+		if (cpu_guest_has_kscr(7))
+			kvm_restore_gc0_kscratch6(cop0);
+	}
+
+	if (cpu_guest_has_badinstr)
+		kvm_restore_gc0_badinstr(cop0);
+	if (cpu_guest_has_badinstrp)
+		kvm_restore_gc0_badinstrp(cop0);
+
+	if (cpu_guest_has_segments) {
+		kvm_restore_gc0_segctl0(cop0);
+		kvm_restore_gc0_segctl1(cop0);
+		kvm_restore_gc0_segctl2(cop0);
+	}
+
+	/* restore HTW registers */
+	if (cpu_guest_has_htw || cpu_guest_has_ldpte) {
+		kvm_restore_gc0_pwbase(cop0);
+		kvm_restore_gc0_pwfield(cop0);
+		kvm_restore_gc0_pwsize(cop0);
+		kvm_restore_gc0_pwctl(cop0);
+	}
+
+	/* restore Root.GuestCtl2 from unused Guest guestctl2 register */
+	if (cpu_has_guestctl2)
+		write_c0_guestctl2(
+			cop0->reg[MIPS_CP0_GUESTCTL2][MIPS_CP0_GUESTCTL2_SEL]);
+
+	/*
+	 * We should clear linked load bit to break interrupted atomics. This
+	 * prevents a SC on the next VCPU from succeeding by matching a LL on
+	 * the previous VCPU.
+	 */
+	if (vcpu->kvm->created_vcpus > 1)
+		write_gc0_lladdr(0);
+
+	return 0;
+}
+
+static int kvm_vz_vcpu_put(struct kvm_vcpu *vcpu, int cpu)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+
+	if (current->flags & PF_VCPU)
+		kvm_vz_vcpu_save_wired(vcpu);
+
+	kvm_lose_fpu(vcpu);
+
+	kvm_save_gc0_index(cop0);
+	kvm_save_gc0_entrylo0(cop0);
+	kvm_save_gc0_entrylo1(cop0);
+	kvm_save_gc0_context(cop0);
+	if (cpu_guest_has_contextconfig)
+		kvm_save_gc0_contextconfig(cop0);
+#ifdef CONFIG_64BIT
+	kvm_save_gc0_xcontext(cop0);
+	if (cpu_guest_has_contextconfig)
+		kvm_save_gc0_xcontextconfig(cop0);
+#endif
+	kvm_save_gc0_pagemask(cop0);
+	kvm_save_gc0_pagegrain(cop0);
+	kvm_save_gc0_wired(cop0);
+	/* allow wired TLB entries to be overwritten */
+	clear_gc0_wired(MIPSR6_WIRED_WIRED);
+	kvm_save_gc0_hwrena(cop0);
+	kvm_save_gc0_badvaddr(cop0);
+	kvm_save_gc0_entryhi(cop0);
+	kvm_save_gc0_status(cop0);
+	kvm_save_gc0_intctl(cop0);
+	kvm_save_gc0_epc(cop0);
+	kvm_write_sw_gc0_ebase(cop0, kvm_vz_read_gc0_ebase());
+	if (cpu_guest_has_userlocal)
+		kvm_save_gc0_userlocal(cop0);
+
+	/* only save implemented config registers */
+	kvm_save_gc0_config(cop0);
+	if (cpu_guest_has_conf1)
+		kvm_save_gc0_config1(cop0);
+	if (cpu_guest_has_conf2)
+		kvm_save_gc0_config2(cop0);
+	if (cpu_guest_has_conf3)
+		kvm_save_gc0_config3(cop0);
+	if (cpu_guest_has_conf4)
+		kvm_save_gc0_config4(cop0);
+	if (cpu_guest_has_conf5)
+		kvm_save_gc0_config5(cop0);
+	if (cpu_guest_has_conf6)
+		kvm_save_gc0_config6(cop0);
+	if (cpu_guest_has_conf7)
+		kvm_save_gc0_config7(cop0);
+
+	kvm_save_gc0_errorepc(cop0);
+
+	/* save KScratch registers if enabled in guest */
+	if (cpu_guest_has_conf4) {
+		if (cpu_guest_has_kscr(2))
+			kvm_save_gc0_kscratch1(cop0);
+		if (cpu_guest_has_kscr(3))
+			kvm_save_gc0_kscratch2(cop0);
+		if (cpu_guest_has_kscr(4))
+			kvm_save_gc0_kscratch3(cop0);
+		if (cpu_guest_has_kscr(5))
+			kvm_save_gc0_kscratch4(cop0);
+		if (cpu_guest_has_kscr(6))
+			kvm_save_gc0_kscratch5(cop0);
+		if (cpu_guest_has_kscr(7))
+			kvm_save_gc0_kscratch6(cop0);
+	}
+
+	if (cpu_guest_has_badinstr)
+		kvm_save_gc0_badinstr(cop0);
+	if (cpu_guest_has_badinstrp)
+		kvm_save_gc0_badinstrp(cop0);
+
+	if (cpu_guest_has_segments) {
+		kvm_save_gc0_segctl0(cop0);
+		kvm_save_gc0_segctl1(cop0);
+		kvm_save_gc0_segctl2(cop0);
+	}
+
+	/* save HTW registers if enabled in guest */
+	if (cpu_guest_has_ldpte || (cpu_guest_has_htw &&
+	    kvm_read_sw_gc0_config3(cop0) & MIPS_CONF3_PW)) {
+		kvm_save_gc0_pwbase(cop0);
+		kvm_save_gc0_pwfield(cop0);
+		kvm_save_gc0_pwsize(cop0);
+		kvm_save_gc0_pwctl(cop0);
+	}
+
+	kvm_vz_save_timer(vcpu);
+
+	/* save Root.GuestCtl2 in unused Guest guestctl2 register */
+	if (cpu_has_guestctl2)
+		cop0->reg[MIPS_CP0_GUESTCTL2][MIPS_CP0_GUESTCTL2_SEL] =
+			read_c0_guestctl2();
+
+	return 0;
+}
+
+/**
+ * kvm_vz_resize_guest_vtlb() - Attempt to resize guest VTLB.
+ * @size:	Number of guest VTLB entries (0 < @size <= root VTLB entries).
+ *
+ * Attempt to resize the guest VTLB by writing guest Config registers. This is
+ * necessary for cores with a shared root/guest TLB to avoid overlap with wired
+ * entries in the root VTLB.
+ *
+ * Returns:	The resulting guest VTLB size.
+ */
+static unsigned int kvm_vz_resize_guest_vtlb(unsigned int size)
+{
+	unsigned int config4 = 0, ret = 0, limit;
+
+	/* Write MMUSize - 1 into guest Config registers */
+	if (cpu_guest_has_conf1)
+		change_gc0_config1(MIPS_CONF1_TLBS,
+				   (size - 1) << MIPS_CONF1_TLBS_SHIFT);
+	if (cpu_guest_has_conf4) {
+		config4 = read_gc0_config4();
+		if (cpu_has_mips_r6 || (config4 & MIPS_CONF4_MMUEXTDEF) ==
+		    MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT) {
+			config4 &= ~MIPS_CONF4_VTLBSIZEEXT;
+			config4 |= ((size - 1) >> MIPS_CONF1_TLBS_SIZE) <<
+				MIPS_CONF4_VTLBSIZEEXT_SHIFT;
+		} else if ((config4 & MIPS_CONF4_MMUEXTDEF) ==
+			   MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT) {
+			config4 &= ~MIPS_CONF4_MMUSIZEEXT;
+			config4 |= ((size - 1) >> MIPS_CONF1_TLBS_SIZE) <<
+				MIPS_CONF4_MMUSIZEEXT_SHIFT;
+		}
+		write_gc0_config4(config4);
+	}
+
+	/*
+	 * Set Guest.Wired.Limit = 0 (no limit up to Guest.MMUSize-1), unless it
+	 * would exceed Root.Wired.Limit (clearing Guest.Wired.Wired so write
+	 * not dropped)
+	 */
+	if (cpu_has_mips_r6) {
+		limit = (read_c0_wired() & MIPSR6_WIRED_LIMIT) >>
+						MIPSR6_WIRED_LIMIT_SHIFT;
+		if (size - 1 <= limit)
+			limit = 0;
+		write_gc0_wired(limit << MIPSR6_WIRED_LIMIT_SHIFT);
+	}
+
+	/* Read back MMUSize - 1 */
+	back_to_back_c0_hazard();
+	if (cpu_guest_has_conf1)
+		ret = (read_gc0_config1() & MIPS_CONF1_TLBS) >>
+						MIPS_CONF1_TLBS_SHIFT;
+	if (config4) {
+		if (cpu_has_mips_r6 || (config4 & MIPS_CONF4_MMUEXTDEF) ==
+		    MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT)
+			ret |= ((config4 & MIPS_CONF4_VTLBSIZEEXT) >>
+				MIPS_CONF4_VTLBSIZEEXT_SHIFT) <<
+				MIPS_CONF1_TLBS_SIZE;
+		else if ((config4 & MIPS_CONF4_MMUEXTDEF) ==
+			 MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT)
+			ret |= ((config4 & MIPS_CONF4_MMUSIZEEXT) >>
+				MIPS_CONF4_MMUSIZEEXT_SHIFT) <<
+				MIPS_CONF1_TLBS_SIZE;
+	}
+	return ret + 1;
+}
+
+static int kvm_vz_hardware_enable(void)
+{
+	unsigned int mmu_size, guest_mmu_size, ftlb_size;
+	u64 guest_cvmctl, cvmvmconfig;
+
+	switch (current_cpu_type()) {
+	case CPU_CAVIUM_OCTEON3:
+		/* Set up guest timer/perfcount IRQ lines */
+		guest_cvmctl = read_gc0_cvmctl();
+		guest_cvmctl &= ~CVMCTL_IPTI;
+		guest_cvmctl |= 7ull << CVMCTL_IPTI_SHIFT;
+		guest_cvmctl &= ~CVMCTL_IPPCI;
+		guest_cvmctl |= 6ull << CVMCTL_IPPCI_SHIFT;
+		write_gc0_cvmctl(guest_cvmctl);
+
+		cvmvmconfig = read_c0_cvmvmconfig();
+		/* No I/O hole translation. */
+		cvmvmconfig |= CVMVMCONF_DGHT;
+		/* Halve the root MMU size */
+		mmu_size = ((cvmvmconfig & CVMVMCONF_MMUSIZEM1)
+			    >> CVMVMCONF_MMUSIZEM1_S) + 1;
+		guest_mmu_size = mmu_size / 2;
+		mmu_size -= guest_mmu_size;
+		cvmvmconfig &= ~CVMVMCONF_RMMUSIZEM1;
+		cvmvmconfig |= mmu_size - 1;
+		write_c0_cvmvmconfig(cvmvmconfig);
+
+		/* Update our records */
+		current_cpu_data.tlbsize = mmu_size;
+		current_cpu_data.tlbsizevtlb = mmu_size;
+		current_cpu_data.guest.tlbsize = guest_mmu_size;
+
+		/* Flush moved entries in new (guest) context */
+		kvm_vz_local_flush_guesttlb_all();
+		break;
+	default:
+		/*
+		 * ImgTec cores tend to use a shared root/guest TLB. To avoid
+		 * overlap of root wired and guest entries, the guest TLB may
+		 * need resizing.
+		 */
+		mmu_size = current_cpu_data.tlbsizevtlb;
+		ftlb_size = current_cpu_data.tlbsize - mmu_size;
+
+		/* Try switching to maximum guest VTLB size for flush */
+		guest_mmu_size = kvm_vz_resize_guest_vtlb(mmu_size);
+		current_cpu_data.guest.tlbsize = guest_mmu_size + ftlb_size;
+		kvm_vz_local_flush_guesttlb_all();
+
+		/*
+		 * Reduce to make space for root wired entries and at least 2
+		 * root non-wired entries. This does assume that long-term wired
+		 * entries won't be added later.
+		 */
+		guest_mmu_size = mmu_size - num_wired_entries() - 2;
+		guest_mmu_size = kvm_vz_resize_guest_vtlb(guest_mmu_size);
+		current_cpu_data.guest.tlbsize = guest_mmu_size + ftlb_size;
+
+		/*
+		 * Write the VTLB size, but if another CPU has already written,
+		 * check it matches or we won't provide a consistent view to the
+		 * guest. If this ever happens it suggests an asymmetric number
+		 * of wired entries.
+		 */
+		if (cmpxchg(&kvm_vz_guest_vtlb_size, 0, guest_mmu_size) &&
+		    WARN(guest_mmu_size != kvm_vz_guest_vtlb_size,
+			 "Available guest VTLB size mismatch"))
+			return -EINVAL;
+		break;
+	}
+
+	/*
+	 * Enable virtualization features granting guest direct control of
+	 * certain features:
+	 * CP0=1:	Guest coprocessor 0 context.
+	 * AT=Guest:	Guest MMU.
+	 * CG=1:	Hit (virtual address) CACHE operations (optional).
+	 * CF=1:	Guest Config registers.
+	 * CGI=1:	Indexed flush CACHE operations (optional).
+	 */
+	write_c0_guestctl0(MIPS_GCTL0_CP0 |
+			   (MIPS_GCTL0_AT_GUEST << MIPS_GCTL0_AT_SHIFT) |
+			   MIPS_GCTL0_CG | MIPS_GCTL0_CF);
+	if (cpu_has_guestctl0ext) {
+		if (current_cpu_type() != CPU_LOONGSON64)
+			set_c0_guestctl0ext(MIPS_GCTL0EXT_CGI);
+		else
+			clear_c0_guestctl0ext(MIPS_GCTL0EXT_CGI);
+	}
+
+	if (cpu_has_guestid) {
+		write_c0_guestctl1(0);
+		kvm_vz_local_flush_roottlb_all_guests();
+
+		GUESTID_MASK = current_cpu_data.guestid_mask;
+		GUESTID_FIRST_VERSION = GUESTID_MASK + 1;
+		GUESTID_VERSION_MASK = ~GUESTID_MASK;
+
+		current_cpu_data.guestid_cache = GUESTID_FIRST_VERSION;
+	}
+
+	/* clear any pending injected virtual guest interrupts */
+	if (cpu_has_guestctl2)
+		clear_c0_guestctl2(0x3f << 10);
+
+#ifdef CONFIG_CPU_LOONGSON64
+	/* Control guest CCA attribute */
+	if (cpu_has_csr())
+		csr_writel(csr_readl(0xffffffec) | 0x1, 0xffffffec);
+#endif
+
+	return 0;
+}
+
+static void kvm_vz_hardware_disable(void)
+{
+	u64 cvmvmconfig;
+	unsigned int mmu_size;
+
+	/* Flush any remaining guest TLB entries */
+	kvm_vz_local_flush_guesttlb_all();
+
+	switch (current_cpu_type()) {
+	case CPU_CAVIUM_OCTEON3:
+		/*
+		 * Allocate whole TLB for root. Existing guest TLB entries will
+		 * change ownership to the root TLB. We should be safe though as
+		 * they've already been flushed above while in guest TLB.
+		 */
+		cvmvmconfig = read_c0_cvmvmconfig();
+		mmu_size = ((cvmvmconfig & CVMVMCONF_MMUSIZEM1)
+			    >> CVMVMCONF_MMUSIZEM1_S) + 1;
+		cvmvmconfig &= ~CVMVMCONF_RMMUSIZEM1;
+		cvmvmconfig |= mmu_size - 1;
+		write_c0_cvmvmconfig(cvmvmconfig);
+
+		/* Update our records */
+		current_cpu_data.tlbsize = mmu_size;
+		current_cpu_data.tlbsizevtlb = mmu_size;
+		current_cpu_data.guest.tlbsize = 0;
+
+		/* Flush moved entries in new (root) context */
+		local_flush_tlb_all();
+		break;
+	}
+
+	if (cpu_has_guestid) {
+		write_c0_guestctl1(0);
+		kvm_vz_local_flush_roottlb_all_guests();
+	}
+}
+
+static int kvm_vz_check_extension(struct kvm *kvm, long ext)
+{
+	int r;
+
+	switch (ext) {
+	case KVM_CAP_MIPS_VZ:
+		/* we wouldn't be here unless cpu_has_vz */
+		r = 1;
+		break;
+#ifdef CONFIG_64BIT
+	case KVM_CAP_MIPS_64BIT:
+		/* We support 64-bit registers/operations and addresses */
+		r = 2;
+		break;
+#endif
+	case KVM_CAP_IOEVENTFD:
+		r = 1;
+		break;
+	default:
+		r = 0;
+		break;
+	}
+
+	return r;
+}
+
+static int kvm_vz_vcpu_init(struct kvm_vcpu *vcpu)
+{
+	int i;
+
+	for_each_possible_cpu(i)
+		vcpu->arch.vzguestid[i] = 0;
+
+	return 0;
+}
+
+static void kvm_vz_vcpu_uninit(struct kvm_vcpu *vcpu)
+{
+	int cpu;
+
+	/*
+	 * If the VCPU is freed and reused as another VCPU, we don't want the
+	 * matching pointer wrongly hanging around in last_vcpu[] or
+	 * last_exec_vcpu[].
+	 */
+	for_each_possible_cpu(cpu) {
+		if (last_vcpu[cpu] == vcpu)
+			last_vcpu[cpu] = NULL;
+		if (last_exec_vcpu[cpu] == vcpu)
+			last_exec_vcpu[cpu] = NULL;
+	}
+}
+
+static int kvm_vz_vcpu_setup(struct kvm_vcpu *vcpu)
+{
+	struct mips_coproc *cop0 = &vcpu->arch.cop0;
+	unsigned long count_hz = 100*1000*1000; /* default to 100 MHz */
+
+	/*
+	 * Start off the timer at the same frequency as the host timer, but the
+	 * soft timer doesn't handle frequencies greater than 1GHz yet.
+	 */
+	if (mips_hpt_frequency && mips_hpt_frequency <= NSEC_PER_SEC)
+		count_hz = mips_hpt_frequency;
+	kvm_mips_init_count(vcpu, count_hz);
+
+	/*
+	 * Initialize guest register state to valid architectural reset state.
+	 */
+
+	/* PageGrain */
+	if (cpu_has_mips_r5 || cpu_has_mips_r6)
+		kvm_write_sw_gc0_pagegrain(cop0, PG_RIE | PG_XIE | PG_IEC);
+	/* Wired */
+	if (cpu_has_mips_r6)
+		kvm_write_sw_gc0_wired(cop0,
+				       read_gc0_wired() & MIPSR6_WIRED_LIMIT);
+	/* Status */
+	kvm_write_sw_gc0_status(cop0, ST0_BEV | ST0_ERL);
+	if (cpu_has_mips_r5 || cpu_has_mips_r6)
+		kvm_change_sw_gc0_status(cop0, ST0_FR, read_gc0_status());
+	/* IntCtl */
+	kvm_write_sw_gc0_intctl(cop0, read_gc0_intctl() &
+				(INTCTLF_IPFDC | INTCTLF_IPPCI | INTCTLF_IPTI));
+	/* PRId */
+	kvm_write_sw_gc0_prid(cop0, boot_cpu_data.processor_id);
+	/* EBase */
+	kvm_write_sw_gc0_ebase(cop0, (s32)0x80000000 | vcpu->vcpu_id);
+	/* Config */
+	kvm_save_gc0_config(cop0);
+	/* architecturally writable (e.g. from guest) */
+	kvm_change_sw_gc0_config(cop0, CONF_CM_CMASK,
+				 _page_cachable_default >> _CACHE_SHIFT);
+	/* architecturally read only, but maybe writable from root */
+	kvm_change_sw_gc0_config(cop0, MIPS_CONF_MT, read_c0_config());
+	if (cpu_guest_has_conf1) {
+		kvm_set_sw_gc0_config(cop0, MIPS_CONF_M);
+		/* Config1 */
+		kvm_save_gc0_config1(cop0);
+		/* architecturally read only, but maybe writable from root */
+		kvm_clear_sw_gc0_config1(cop0, MIPS_CONF1_C2	|
+					       MIPS_CONF1_MD	|
+					       MIPS_CONF1_PC	|
+					       MIPS_CONF1_WR	|
+					       MIPS_CONF1_CA	|
+					       MIPS_CONF1_FP);
+	}
+	if (cpu_guest_has_conf2) {
+		kvm_set_sw_gc0_config1(cop0, MIPS_CONF_M);
+		/* Config2 */
+		kvm_save_gc0_config2(cop0);
+	}
+	if (cpu_guest_has_conf3) {
+		kvm_set_sw_gc0_config2(cop0, MIPS_CONF_M);
+		/* Config3 */
+		kvm_save_gc0_config3(cop0);
+		/* architecturally writable (e.g. from guest) */
+		kvm_clear_sw_gc0_config3(cop0, MIPS_CONF3_ISA_OE);
+		/* architecturally read only, but maybe writable from root */
+		kvm_clear_sw_gc0_config3(cop0, MIPS_CONF3_MSA	|
+					       MIPS_CONF3_BPG	|
+					       MIPS_CONF3_ULRI	|
+					       MIPS_CONF3_DSP	|
+					       MIPS_CONF3_CTXTC	|
+					       MIPS_CONF3_ITL	|
+					       MIPS_CONF3_LPA	|
+					       MIPS_CONF3_VEIC	|
+					       MIPS_CONF3_VINT	|
+					       MIPS_CONF3_SP	|
+					       MIPS_CONF3_CDMM	|
+					       MIPS_CONF3_MT	|
+					       MIPS_CONF3_SM	|
+					       MIPS_CONF3_TL);
+	}
+	if (cpu_guest_has_conf4) {
+		kvm_set_sw_gc0_config3(cop0, MIPS_CONF_M);
+		/* Config4 */
+		kvm_save_gc0_config4(cop0);
+	}
+	if (cpu_guest_has_conf5) {
+		kvm_set_sw_gc0_config4(cop0, MIPS_CONF_M);
+		/* Config5 */
+		kvm_save_gc0_config5(cop0);
+		/* architecturally writable (e.g. from guest) */
+		kvm_clear_sw_gc0_config5(cop0, MIPS_CONF5_K	|
+					       MIPS_CONF5_CV	|
+					       MIPS_CONF5_MSAEN	|
+					       MIPS_CONF5_UFE	|
+					       MIPS_CONF5_FRE	|
+					       MIPS_CONF5_SBRI	|
+					       MIPS_CONF5_UFR);
+		/* architecturally read only, but maybe writable from root */
+		kvm_clear_sw_gc0_config5(cop0, MIPS_CONF5_MRP);
+	}
+
+	if (cpu_guest_has_contextconfig) {
+		/* ContextConfig */
+		kvm_write_sw_gc0_contextconfig(cop0, 0x007ffff0);
+#ifdef CONFIG_64BIT
+		/* XContextConfig */
+		/* bits SEGBITS-13+3:4 set */
+		kvm_write_sw_gc0_xcontextconfig(cop0,
+					((1ull << (cpu_vmbits - 13)) - 1) << 4);
+#endif
+	}
+
+	/* Implementation dependent, use the legacy layout */
+	if (cpu_guest_has_segments) {
+		/* SegCtl0, SegCtl1, SegCtl2 */
+		kvm_write_sw_gc0_segctl0(cop0, 0x00200010);
+		kvm_write_sw_gc0_segctl1(cop0, 0x00000002 |
+				(_page_cachable_default >> _CACHE_SHIFT) <<
+						(16 + MIPS_SEGCFG_C_SHIFT));
+		kvm_write_sw_gc0_segctl2(cop0, 0x00380438);
+	}
+
+	/* reset HTW registers */
+	if (cpu_guest_has_htw && (cpu_has_mips_r5 || cpu_has_mips_r6)) {
+		/* PWField */
+		kvm_write_sw_gc0_pwfield(cop0, 0x0c30c302);
+		/* PWSize */
+		kvm_write_sw_gc0_pwsize(cop0, 1 << MIPS_PWSIZE_PTW_SHIFT);
+	}
+
+	/* start with no pending virtual guest interrupts */
+	if (cpu_has_guestctl2)
+		cop0->reg[MIPS_CP0_GUESTCTL2][MIPS_CP0_GUESTCTL2_SEL] = 0;
+
+	/* Put PC at reset vector */
+	vcpu->arch.pc = CKSEG1ADDR(0x1fc00000);
+
+	return 0;
+}
+
+static void kvm_vz_prepare_flush_shadow(struct kvm *kvm)
+{
+	if (!cpu_has_guestid) {
+		/*
+		 * For each CPU there is a single GPA ASID used by all VCPUs in
+		 * the VM, so it doesn't make sense for the VCPUs to handle
+		 * invalidation of these ASIDs individually.
+		 *
+		 * Instead mark all CPUs as needing ASID invalidation in
+		 * asid_flush_mask, and kvm_flush_remote_tlbs(kvm) will
+		 * kick any running VCPUs so they check asid_flush_mask.
+		 */
+		cpumask_setall(&kvm->arch.asid_flush_mask);
+	}
+}
+
+static void kvm_vz_vcpu_reenter(struct kvm_vcpu *vcpu)
+{
+	int cpu = smp_processor_id();
+	int preserve_guest_tlb;
+
+	preserve_guest_tlb = kvm_vz_check_requests(vcpu, cpu);
+
+	if (preserve_guest_tlb)
+		kvm_vz_vcpu_save_wired(vcpu);
+
+	kvm_vz_vcpu_load_tlb(vcpu, cpu);
+
+	if (preserve_guest_tlb)
+		kvm_vz_vcpu_load_wired(vcpu);
+}
+
+static int kvm_vz_vcpu_run(struct kvm_vcpu *vcpu)
+{
+	int cpu = smp_processor_id();
+	int r;
+
+	kvm_vz_acquire_htimer(vcpu);
+	/* Check if we have any exceptions/interrupts pending */
+	kvm_mips_deliver_interrupts(vcpu, read_gc0_cause());
+
+	kvm_vz_check_requests(vcpu, cpu);
+	kvm_vz_vcpu_load_tlb(vcpu, cpu);
+	kvm_vz_vcpu_load_wired(vcpu);
+
+	r = vcpu->arch.vcpu_run(vcpu);
+
+	kvm_vz_vcpu_save_wired(vcpu);
+
+	return r;
+}
+
+static struct kvm_mips_callbacks kvm_vz_callbacks = {
+	.handle_cop_unusable = kvm_trap_vz_handle_cop_unusable,
+	.handle_tlb_mod = kvm_trap_vz_handle_tlb_st_miss,
+	.handle_tlb_ld_miss = kvm_trap_vz_handle_tlb_ld_miss,
+	.handle_tlb_st_miss = kvm_trap_vz_handle_tlb_st_miss,
+	.handle_addr_err_st = kvm_trap_vz_no_handler,
+	.handle_addr_err_ld = kvm_trap_vz_no_handler,
+	.handle_syscall = kvm_trap_vz_no_handler,
+	.handle_res_inst = kvm_trap_vz_no_handler,
+	.handle_break = kvm_trap_vz_no_handler,
+	.handle_msa_disabled = kvm_trap_vz_handle_msa_disabled,
+	.handle_guest_exit = kvm_trap_vz_handle_guest_exit,
+
+	.hardware_enable = kvm_vz_hardware_enable,
+	.hardware_disable = kvm_vz_hardware_disable,
+	.check_extension = kvm_vz_check_extension,
+	.vcpu_init = kvm_vz_vcpu_init,
+	.vcpu_uninit = kvm_vz_vcpu_uninit,
+	.vcpu_setup = kvm_vz_vcpu_setup,
+	.prepare_flush_shadow = kvm_vz_prepare_flush_shadow,
+	.gva_to_gpa = kvm_vz_gva_to_gpa_cb,
+	.queue_timer_int = kvm_vz_queue_timer_int_cb,
+	.dequeue_timer_int = kvm_vz_dequeue_timer_int_cb,
+	.queue_io_int = kvm_vz_queue_io_int_cb,
+	.dequeue_io_int = kvm_vz_dequeue_io_int_cb,
+	.irq_deliver = kvm_vz_irq_deliver_cb,
+	.irq_clear = kvm_vz_irq_clear_cb,
+	.num_regs = kvm_vz_num_regs,
+	.copy_reg_indices = kvm_vz_copy_reg_indices,
+	.get_one_reg = kvm_vz_get_one_reg,
+	.set_one_reg = kvm_vz_set_one_reg,
+	.vcpu_load = kvm_vz_vcpu_load,
+	.vcpu_put = kvm_vz_vcpu_put,
+	.vcpu_run = kvm_vz_vcpu_run,
+	.vcpu_reenter = kvm_vz_vcpu_reenter,
+};
+
+/* FIXME: Get rid of the callbacks now that trap-and-emulate is gone. */
+const struct kvm_mips_callbacks * const kvm_mips_callbacks = &kvm_vz_callbacks;
+
+int kvm_mips_emulation_init(void)
+{
+	if (!cpu_has_vz)
+		return -ENODEV;
+
+	/*
+	 * VZ requires at least 2 KScratch registers, so it should have been
+	 * possible to allocate pgd_reg.
+	 */
+	if (WARN(pgd_reg == -1,
+		 "pgd_reg not allocated even though cpu_has_vz\n"))
+		return -ENODEV;
+
+	pr_info("Starting KVM with MIPS VZ extensions\n");
+	return 0;
+}