Adding upstream version 4.19.249.upstream/4.19.249upstream

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

1 files changed, 2606 insertions, 0 deletions

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
new file mode 100644
index 000000000..f06629bf2
--- /dev/null
+++ b/arch/arm64/kvm/sys_regs.c
@@ -0,0 +1,2606 @@
+/*
+ * Copyright (C) 2012,2013 - ARM Ltd
+ * Author: Marc Zyngier <marc.zyngier@arm.com>
+ *
+ * Derived from arch/arm/kvm/coproc.c:
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Authors: Rusty Russell <rusty@rustcorp.com.au>
+ *          Christoffer Dall <c.dall@virtualopensystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/bsearch.h>
+#include <linux/kvm_host.h>
+#include <linux/mm.h>
+#include <linux/printk.h>
+#include <linux/uaccess.h>
+
+#include <asm/cacheflush.h>
+#include <asm/cputype.h>
+#include <asm/debug-monitors.h>
+#include <asm/esr.h>
+#include <asm/kvm_arm.h>
+#include <asm/kvm_coproc.h>
+#include <asm/kvm_emulate.h>
+#include <asm/kvm_host.h>
+#include <asm/kvm_hyp.h>
+#include <asm/kvm_mmu.h>
+#include <asm/perf_event.h>
+#include <asm/sysreg.h>
+
+#include <trace/events/kvm.h>
+
+#include "sys_regs.h"
+
+#include "trace.h"
+
+/*
+ * All of this file is extremly similar to the ARM coproc.c, but the
+ * types are different. My gut feeling is that it should be pretty
+ * easy to merge, but that would be an ABI breakage -- again. VFP
+ * would also need to be abstracted.
+ *
+ * For AArch32, we only take care of what is being trapped. Anything
+ * that has to do with init and userspace access has to go via the
+ * 64bit interface.
+ */
+
+static bool read_from_write_only(struct kvm_vcpu *vcpu,
+				 struct sys_reg_params *params,
+				 const struct sys_reg_desc *r)
+{
+	WARN_ONCE(1, "Unexpected sys_reg read to write-only register\n");
+	print_sys_reg_instr(params);
+	kvm_inject_undefined(vcpu);
+	return false;
+}
+
+static bool write_to_read_only(struct kvm_vcpu *vcpu,
+			       struct sys_reg_params *params,
+			       const struct sys_reg_desc *r)
+{
+	WARN_ONCE(1, "Unexpected sys_reg write to read-only register\n");
+	print_sys_reg_instr(params);
+	kvm_inject_undefined(vcpu);
+	return false;
+}
+
+u64 vcpu_read_sys_reg(struct kvm_vcpu *vcpu, int reg)
+{
+	if (!vcpu->arch.sysregs_loaded_on_cpu)
+		goto immediate_read;
+
+	/*
+	 * System registers listed in the switch are not saved on every
+	 * exit from the guest but are only saved on vcpu_put.
+	 *
+	 * Note that MPIDR_EL1 for the guest is set by KVM via VMPIDR_EL2 but
+	 * should never be listed below, because the guest cannot modify its
+	 * own MPIDR_EL1 and MPIDR_EL1 is accessed for VCPU A from VCPU B's
+	 * thread when emulating cross-VCPU communication.
+	 */
+	switch (reg) {
+	case CSSELR_EL1:	return read_sysreg_s(SYS_CSSELR_EL1);
+	case SCTLR_EL1:		return read_sysreg_s(sctlr_EL12);
+	case ACTLR_EL1:		return read_sysreg_s(SYS_ACTLR_EL1);
+	case CPACR_EL1:		return read_sysreg_s(cpacr_EL12);
+	case TTBR0_EL1:		return read_sysreg_s(ttbr0_EL12);
+	case TTBR1_EL1:		return read_sysreg_s(ttbr1_EL12);
+	case TCR_EL1:		return read_sysreg_s(tcr_EL12);
+	case ESR_EL1:		return read_sysreg_s(esr_EL12);
+	case AFSR0_EL1:		return read_sysreg_s(afsr0_EL12);
+	case AFSR1_EL1:		return read_sysreg_s(afsr1_EL12);
+	case FAR_EL1:		return read_sysreg_s(far_EL12);
+	case MAIR_EL1:		return read_sysreg_s(mair_EL12);
+	case VBAR_EL1:		return read_sysreg_s(vbar_EL12);
+	case CONTEXTIDR_EL1:	return read_sysreg_s(contextidr_EL12);
+	case TPIDR_EL0:		return read_sysreg_s(SYS_TPIDR_EL0);
+	case TPIDRRO_EL0:	return read_sysreg_s(SYS_TPIDRRO_EL0);
+	case TPIDR_EL1:		return read_sysreg_s(SYS_TPIDR_EL1);
+	case AMAIR_EL1:		return read_sysreg_s(amair_EL12);
+	case CNTKCTL_EL1:	return read_sysreg_s(cntkctl_EL12);
+	case PAR_EL1:		return read_sysreg_s(SYS_PAR_EL1);
+	case DACR32_EL2:	return read_sysreg_s(SYS_DACR32_EL2);
+	case IFSR32_EL2:	return read_sysreg_s(SYS_IFSR32_EL2);
+	case DBGVCR32_EL2:	return read_sysreg_s(SYS_DBGVCR32_EL2);
+	}
+
+immediate_read:
+	return __vcpu_sys_reg(vcpu, reg);
+}
+
+void vcpu_write_sys_reg(struct kvm_vcpu *vcpu, u64 val, int reg)
+{
+	if (!vcpu->arch.sysregs_loaded_on_cpu)
+		goto immediate_write;
+
+	/*
+	 * System registers listed in the switch are not restored on every
+	 * entry to the guest but are only restored on vcpu_load.
+	 *
+	 * Note that MPIDR_EL1 for the guest is set by KVM via VMPIDR_EL2 but
+	 * should never be listed below, because the the MPIDR should only be
+	 * set once, before running the VCPU, and never changed later.
+	 */
+	switch (reg) {
+	case CSSELR_EL1:	write_sysreg_s(val, SYS_CSSELR_EL1);	return;
+	case SCTLR_EL1:		write_sysreg_s(val, sctlr_EL12);	return;
+	case ACTLR_EL1:		write_sysreg_s(val, SYS_ACTLR_EL1);	return;
+	case CPACR_EL1:		write_sysreg_s(val, cpacr_EL12);	return;
+	case TTBR0_EL1:		write_sysreg_s(val, ttbr0_EL12);	return;
+	case TTBR1_EL1:		write_sysreg_s(val, ttbr1_EL12);	return;
+	case TCR_EL1:		write_sysreg_s(val, tcr_EL12);		return;
+	case ESR_EL1:		write_sysreg_s(val, esr_EL12);		return;
+	case AFSR0_EL1:		write_sysreg_s(val, afsr0_EL12);	return;
+	case AFSR1_EL1:		write_sysreg_s(val, afsr1_EL12);	return;
+	case FAR_EL1:		write_sysreg_s(val, far_EL12);		return;
+	case MAIR_EL1:		write_sysreg_s(val, mair_EL12);		return;
+	case VBAR_EL1:		write_sysreg_s(val, vbar_EL12);		return;
+	case CONTEXTIDR_EL1:	write_sysreg_s(val, contextidr_EL12);	return;
+	case TPIDR_EL0:		write_sysreg_s(val, SYS_TPIDR_EL0);	return;
+	case TPIDRRO_EL0:	write_sysreg_s(val, SYS_TPIDRRO_EL0);	return;
+	case TPIDR_EL1:		write_sysreg_s(val, SYS_TPIDR_EL1);	return;
+	case AMAIR_EL1:		write_sysreg_s(val, amair_EL12);	return;
+	case CNTKCTL_EL1:	write_sysreg_s(val, cntkctl_EL12);	return;
+	case PAR_EL1:		write_sysreg_s(val, SYS_PAR_EL1);	return;
+	case DACR32_EL2:	write_sysreg_s(val, SYS_DACR32_EL2);	return;
+	case IFSR32_EL2:	write_sysreg_s(val, SYS_IFSR32_EL2);	return;
+	case DBGVCR32_EL2:	write_sysreg_s(val, SYS_DBGVCR32_EL2);	return;
+	}
+
+immediate_write:
+	 __vcpu_sys_reg(vcpu, reg) = val;
+}
+
+/* 3 bits per cache level, as per CLIDR, but non-existent caches always 0 */
+static u32 cache_levels;
+
+/* CSSELR values; used to index KVM_REG_ARM_DEMUX_ID_CCSIDR */
+#define CSSELR_MAX 12
+
+/* Which cache CCSIDR represents depends on CSSELR value. */
+static u32 get_ccsidr(u32 csselr)
+{
+	u32 ccsidr;
+
+	/* Make sure noone else changes CSSELR during this! */
+	local_irq_disable();
+	write_sysreg(csselr, csselr_el1);
+	isb();
+	ccsidr = read_sysreg(ccsidr_el1);
+	local_irq_enable();
+
+	return ccsidr;
+}
+
+/*
+ * See note at ARMv7 ARM B1.14.4 (TL;DR: S/W ops are not easily virtualized).
+ */
+static bool access_dcsw(struct kvm_vcpu *vcpu,
+			struct sys_reg_params *p,
+			const struct sys_reg_desc *r)
+{
+	if (!p->is_write)
+		return read_from_write_only(vcpu, p, r);
+
+	/*
+	 * Only track S/W ops if we don't have FWB. It still indicates
+	 * that the guest is a bit broken (S/W operations should only
+	 * be done by firmware, knowing that there is only a single
+	 * CPU left in the system, and certainly not from non-secure
+	 * software).
+	 */
+	if (!cpus_have_const_cap(ARM64_HAS_STAGE2_FWB))
+		kvm_set_way_flush(vcpu);
+
+	return true;
+}
+
+/*
+ * Generic accessor for VM registers. Only called as long as HCR_TVM
+ * is set. If the guest enables the MMU, we stop trapping the VM
+ * sys_regs and leave it in complete control of the caches.
+ */
+static bool access_vm_reg(struct kvm_vcpu *vcpu,
+			  struct sys_reg_params *p,
+			  const struct sys_reg_desc *r)
+{
+	bool was_enabled = vcpu_has_cache_enabled(vcpu);
+	u64 val;
+	int reg = r->reg;
+
+	BUG_ON(!p->is_write);
+
+	/* See the 32bit mapping in kvm_host.h */
+	if (p->is_aarch32)
+		reg = r->reg / 2;
+
+	if (!p->is_aarch32 || !p->is_32bit) {
+		val = p->regval;
+	} else {
+		val = vcpu_read_sys_reg(vcpu, reg);
+		if (r->reg % 2)
+			val = (p->regval << 32) | (u64)lower_32_bits(val);
+		else
+			val = ((u64)upper_32_bits(val) << 32) |
+				lower_32_bits(p->regval);
+	}
+	vcpu_write_sys_reg(vcpu, val, reg);
+
+	kvm_toggle_cache(vcpu, was_enabled);
+	return true;
+}
+
+/*
+ * Trap handler for the GICv3 SGI generation system register.
+ * Forward the request to the VGIC emulation.
+ * The cp15_64 code makes sure this automatically works
+ * for both AArch64 and AArch32 accesses.
+ */
+static bool access_gic_sgi(struct kvm_vcpu *vcpu,
+			   struct sys_reg_params *p,
+			   const struct sys_reg_desc *r)
+{
+	bool g1;
+
+	if (!p->is_write)
+		return read_from_write_only(vcpu, p, r);
+
+	/*
+	 * In a system where GICD_CTLR.DS=1, a ICC_SGI0R_EL1 access generates
+	 * Group0 SGIs only, while ICC_SGI1R_EL1 can generate either group,
+	 * depending on the SGI configuration. ICC_ASGI1R_EL1 is effectively
+	 * equivalent to ICC_SGI0R_EL1, as there is no "alternative" secure
+	 * group.
+	 */
+	if (p->is_aarch32) {
+		switch (p->Op1) {
+		default:		/* Keep GCC quiet */
+		case 0:			/* ICC_SGI1R */
+			g1 = true;
+			break;
+		case 1:			/* ICC_ASGI1R */
+		case 2:			/* ICC_SGI0R */
+			g1 = false;
+			break;
+		}
+	} else {
+		switch (p->Op2) {
+		default:		/* Keep GCC quiet */
+		case 5:			/* ICC_SGI1R_EL1 */
+			g1 = true;
+			break;
+		case 6:			/* ICC_ASGI1R_EL1 */
+		case 7:			/* ICC_SGI0R_EL1 */
+			g1 = false;
+			break;
+		}
+	}
+
+	vgic_v3_dispatch_sgi(vcpu, p->regval, g1);
+
+	return true;
+}
+
+static bool access_gic_sre(struct kvm_vcpu *vcpu,
+			   struct sys_reg_params *p,
+			   const struct sys_reg_desc *r)
+{
+	if (p->is_write)
+		return ignore_write(vcpu, p);
+
+	p->regval = vcpu->arch.vgic_cpu.vgic_v3.vgic_sre;
+	return true;
+}
+
+static bool trap_raz_wi(struct kvm_vcpu *vcpu,
+			struct sys_reg_params *p,
+			const struct sys_reg_desc *r)
+{
+	if (p->is_write)
+		return ignore_write(vcpu, p);
+	else
+		return read_zero(vcpu, p);
+}
+
+static bool trap_undef(struct kvm_vcpu *vcpu,
+		       struct sys_reg_params *p,
+		       const struct sys_reg_desc *r)
+{
+	kvm_inject_undefined(vcpu);
+	return false;
+}
+
+static bool trap_oslsr_el1(struct kvm_vcpu *vcpu,
+			   struct sys_reg_params *p,
+			   const struct sys_reg_desc *r)
+{
+	if (p->is_write) {
+		return ignore_write(vcpu, p);
+	} else {
+		p->regval = (1 << 3);
+		return true;
+	}
+}
+
+static bool trap_dbgauthstatus_el1(struct kvm_vcpu *vcpu,
+				   struct sys_reg_params *p,
+				   const struct sys_reg_desc *r)
+{
+	if (p->is_write) {
+		return ignore_write(vcpu, p);
+	} else {
+		p->regval = read_sysreg(dbgauthstatus_el1);
+		return true;
+	}
+}
+
+/*
+ * We want to avoid world-switching all the DBG registers all the
+ * time:
+ * 
+ * - If we've touched any debug register, it is likely that we're
+ *   going to touch more of them. It then makes sense to disable the
+ *   traps and start doing the save/restore dance
+ * - If debug is active (DBG_MDSCR_KDE or DBG_MDSCR_MDE set), it is
+ *   then mandatory to save/restore the registers, as the guest
+ *   depends on them.
+ * 
+ * For this, we use a DIRTY bit, indicating the guest has modified the
+ * debug registers, used as follow:
+ *
+ * On guest entry:
+ * - If the dirty bit is set (because we're coming back from trapping),
+ *   disable the traps, save host registers, restore guest registers.
+ * - If debug is actively in use (DBG_MDSCR_KDE or DBG_MDSCR_MDE set),
+ *   set the dirty bit, disable the traps, save host registers,
+ *   restore guest registers.
+ * - Otherwise, enable the traps
+ *
+ * On guest exit:
+ * - If the dirty bit is set, save guest registers, restore host
+ *   registers and clear the dirty bit. This ensure that the host can
+ *   now use the debug registers.
+ */
+static bool trap_debug_regs(struct kvm_vcpu *vcpu,
+			    struct sys_reg_params *p,
+			    const struct sys_reg_desc *r)
+{
+	if (p->is_write) {
+		vcpu_write_sys_reg(vcpu, p->regval, r->reg);
+		vcpu->arch.flags |= KVM_ARM64_DEBUG_DIRTY;
+	} else {
+		p->regval = vcpu_read_sys_reg(vcpu, r->reg);
+	}
+
+	trace_trap_reg(__func__, r->reg, p->is_write, p->regval);
+
+	return true;
+}
+
+/*
+ * reg_to_dbg/dbg_to_reg
+ *
+ * A 32 bit write to a debug register leave top bits alone
+ * A 32 bit read from a debug register only returns the bottom bits
+ *
+ * All writes will set the KVM_ARM64_DEBUG_DIRTY flag to ensure the
+ * hyp.S code switches between host and guest values in future.
+ */
+static void reg_to_dbg(struct kvm_vcpu *vcpu,
+		       struct sys_reg_params *p,
+		       u64 *dbg_reg)
+{
+	u64 val = p->regval;
+
+	if (p->is_32bit) {
+		val &= 0xffffffffUL;
+		val |= ((*dbg_reg >> 32) << 32);
+	}
+
+	*dbg_reg = val;
+	vcpu->arch.flags |= KVM_ARM64_DEBUG_DIRTY;
+}
+
+static void dbg_to_reg(struct kvm_vcpu *vcpu,
+		       struct sys_reg_params *p,
+		       u64 *dbg_reg)
+{
+	p->regval = *dbg_reg;
+	if (p->is_32bit)
+		p->regval &= 0xffffffffUL;
+}
+
+static bool trap_bvr(struct kvm_vcpu *vcpu,
+		     struct sys_reg_params *p,
+		     const struct sys_reg_desc *rd)
+{
+	u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_bvr[rd->CRm];
+
+	if (p->is_write)
+		reg_to_dbg(vcpu, p, dbg_reg);
+	else
+		dbg_to_reg(vcpu, p, dbg_reg);
+
+	trace_trap_reg(__func__, rd->CRm, p->is_write, *dbg_reg);
+
+	return true;
+}
+
+static int set_bvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
+		const struct kvm_one_reg *reg, void __user *uaddr)
+{
+	__u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bvr[rd->CRm];
+
+	if (copy_from_user(r, uaddr, KVM_REG_SIZE(reg->id)) != 0)
+		return -EFAULT;
+	return 0;
+}
+
+static int get_bvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
+	const struct kvm_one_reg *reg, void __user *uaddr)
+{
+	__u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bvr[rd->CRm];
+
+	if (copy_to_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0)
+		return -EFAULT;
+	return 0;
+}
+
+static void reset_bvr(struct kvm_vcpu *vcpu,
+		      const struct sys_reg_desc *rd)
+{
+	vcpu->arch.vcpu_debug_state.dbg_bvr[rd->CRm] = rd->val;
+}
+
+static bool trap_bcr(struct kvm_vcpu *vcpu,
+		     struct sys_reg_params *p,
+		     const struct sys_reg_desc *rd)
+{
+	u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_bcr[rd->CRm];
+
+	if (p->is_write)
+		reg_to_dbg(vcpu, p, dbg_reg);
+	else
+		dbg_to_reg(vcpu, p, dbg_reg);
+
+	trace_trap_reg(__func__, rd->CRm, p->is_write, *dbg_reg);
+
+	return true;
+}
+
+static int set_bcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
+		const struct kvm_one_reg *reg, void __user *uaddr)
+{
+	__u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bcr[rd->CRm];
+
+	if (copy_from_user(r, uaddr, KVM_REG_SIZE(reg->id)) != 0)
+		return -EFAULT;
+
+	return 0;
+}
+
+static int get_bcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
+	const struct kvm_one_reg *reg, void __user *uaddr)
+{
+	__u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bcr[rd->CRm];
+
+	if (copy_to_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0)
+		return -EFAULT;
+	return 0;
+}
+
+static void reset_bcr(struct kvm_vcpu *vcpu,
+		      const struct sys_reg_desc *rd)
+{
+	vcpu->arch.vcpu_debug_state.dbg_bcr[rd->CRm] = rd->val;
+}
+
+static bool trap_wvr(struct kvm_vcpu *vcpu,
+		     struct sys_reg_params *p,
+		     const struct sys_reg_desc *rd)
+{
+	u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_wvr[rd->CRm];
+
+	if (p->is_write)
+		reg_to_dbg(vcpu, p, dbg_reg);
+	else
+		dbg_to_reg(vcpu, p, dbg_reg);
+
+	trace_trap_reg(__func__, rd->CRm, p->is_write,
+		vcpu->arch.vcpu_debug_state.dbg_wvr[rd->CRm]);
+
+	return true;
+}
+
+static int set_wvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
+		const struct kvm_one_reg *reg, void __user *uaddr)
+{
+	__u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wvr[rd->CRm];
+
+	if (copy_from_user(r, uaddr, KVM_REG_SIZE(reg->id)) != 0)
+		return -EFAULT;
+	return 0;
+}
+
+static int get_wvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
+	const struct kvm_one_reg *reg, void __user *uaddr)
+{
+	__u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wvr[rd->CRm];
+
+	if (copy_to_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0)
+		return -EFAULT;
+	return 0;
+}
+
+static void reset_wvr(struct kvm_vcpu *vcpu,
+		      const struct sys_reg_desc *rd)
+{
+	vcpu->arch.vcpu_debug_state.dbg_wvr[rd->CRm] = rd->val;
+}
+
+static bool trap_wcr(struct kvm_vcpu *vcpu,
+		     struct sys_reg_params *p,
+		     const struct sys_reg_desc *rd)
+{
+	u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_wcr[rd->CRm];
+
+	if (p->is_write)
+		reg_to_dbg(vcpu, p, dbg_reg);
+	else
+		dbg_to_reg(vcpu, p, dbg_reg);
+
+	trace_trap_reg(__func__, rd->CRm, p->is_write, *dbg_reg);
+
+	return true;
+}
+
+static int set_wcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
+		const struct kvm_one_reg *reg, void __user *uaddr)
+{
+	__u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wcr[rd->CRm];
+
+	if (copy_from_user(r, uaddr, KVM_REG_SIZE(reg->id)) != 0)
+		return -EFAULT;
+	return 0;
+}
+
+static int get_wcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
+	const struct kvm_one_reg *reg, void __user *uaddr)
+{
+	__u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wcr[rd->CRm];
+
+	if (copy_to_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0)
+		return -EFAULT;
+	return 0;
+}
+
+static void reset_wcr(struct kvm_vcpu *vcpu,
+		      const struct sys_reg_desc *rd)
+{
+	vcpu->arch.vcpu_debug_state.dbg_wcr[rd->CRm] = rd->val;
+}
+
+static void reset_amair_el1(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
+{
+	u64 amair = read_sysreg(amair_el1);
+	vcpu_write_sys_reg(vcpu, amair, AMAIR_EL1);
+}
+
+static void reset_mpidr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
+{
+	u64 mpidr;
+
+	/*
+	 * Map the vcpu_id into the first three affinity level fields of
+	 * the MPIDR. We limit the number of VCPUs in level 0 due to a
+	 * limitation to 16 CPUs in that level in the ICC_SGIxR registers
+	 * of the GICv3 to be able to address each CPU directly when
+	 * sending IPIs.
+	 */
+	mpidr = (vcpu->vcpu_id & 0x0f) << MPIDR_LEVEL_SHIFT(0);
+	mpidr |= ((vcpu->vcpu_id >> 4) & 0xff) << MPIDR_LEVEL_SHIFT(1);
+	mpidr |= ((vcpu->vcpu_id >> 12) & 0xff) << MPIDR_LEVEL_SHIFT(2);
+	vcpu_write_sys_reg(vcpu, (1ULL << 31) | mpidr, MPIDR_EL1);
+}
+
+static void reset_pmcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
+{
+	u64 pmcr, val;
+
+	/* No PMU available, PMCR_EL0 may UNDEF... */
+	if (!kvm_arm_support_pmu_v3())
+		return;
+
+	pmcr = read_sysreg(pmcr_el0);
+	/*
+	 * Writable bits of PMCR_EL0 (ARMV8_PMU_PMCR_MASK) are reset to UNKNOWN
+	 * except PMCR.E resetting to zero.
+	 */
+	val = ((pmcr & ~ARMV8_PMU_PMCR_MASK)
+	       | (ARMV8_PMU_PMCR_MASK & 0xdecafbad)) & (~ARMV8_PMU_PMCR_E);
+	__vcpu_sys_reg(vcpu, r->reg) = val;
+}
+
+static bool check_pmu_access_disabled(struct kvm_vcpu *vcpu, u64 flags)
+{
+	u64 reg = __vcpu_sys_reg(vcpu, PMUSERENR_EL0);
+	bool enabled = (reg & flags) || vcpu_mode_priv(vcpu);
+
+	if (!enabled)
+		kvm_inject_undefined(vcpu);
+
+	return !enabled;
+}
+
+static bool pmu_access_el0_disabled(struct kvm_vcpu *vcpu)
+{
+	return check_pmu_access_disabled(vcpu, ARMV8_PMU_USERENR_EN);
+}
+
+static bool pmu_write_swinc_el0_disabled(struct kvm_vcpu *vcpu)
+{
+	return check_pmu_access_disabled(vcpu, ARMV8_PMU_USERENR_SW | ARMV8_PMU_USERENR_EN);
+}
+
+static bool pmu_access_cycle_counter_el0_disabled(struct kvm_vcpu *vcpu)
+{
+	return check_pmu_access_disabled(vcpu, ARMV8_PMU_USERENR_CR | ARMV8_PMU_USERENR_EN);
+}
+
+static bool pmu_access_event_counter_el0_disabled(struct kvm_vcpu *vcpu)
+{
+	return check_pmu_access_disabled(vcpu, ARMV8_PMU_USERENR_ER | ARMV8_PMU_USERENR_EN);
+}
+
+static bool access_pmcr(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
+			const struct sys_reg_desc *r)
+{
+	u64 val;
+
+	if (!kvm_arm_pmu_v3_ready(vcpu))
+		return trap_raz_wi(vcpu, p, r);
+
+	if (pmu_access_el0_disabled(vcpu))
+		return false;
+
+	if (p->is_write) {
+		/* Only update writeable bits of PMCR */
+		val = __vcpu_sys_reg(vcpu, PMCR_EL0);
+		val &= ~ARMV8_PMU_PMCR_MASK;
+		val |= p->regval & ARMV8_PMU_PMCR_MASK;
+		__vcpu_sys_reg(vcpu, PMCR_EL0) = val;
+		kvm_pmu_handle_pmcr(vcpu, val);
+	} else {
+		/* PMCR.P & PMCR.C are RAZ */
+		val = __vcpu_sys_reg(vcpu, PMCR_EL0)
+		      & ~(ARMV8_PMU_PMCR_P | ARMV8_PMU_PMCR_C);
+		p->regval = val;
+	}
+
+	return true;
+}
+
+static bool access_pmselr(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
+			  const struct sys_reg_desc *r)
+{
+	if (!kvm_arm_pmu_v3_ready(vcpu))
+		return trap_raz_wi(vcpu, p, r);
+
+	if (pmu_access_event_counter_el0_disabled(vcpu))
+		return false;
+
+	if (p->is_write)
+		__vcpu_sys_reg(vcpu, PMSELR_EL0) = p->regval;
+	else
+		/* return PMSELR.SEL field */
+		p->regval = __vcpu_sys_reg(vcpu, PMSELR_EL0)
+			    & ARMV8_PMU_COUNTER_MASK;
+
+	return true;
+}
+
+static bool access_pmceid(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
+			  const struct sys_reg_desc *r)
+{
+	u64 pmceid;
+
+	if (!kvm_arm_pmu_v3_ready(vcpu))
+		return trap_raz_wi(vcpu, p, r);
+
+	BUG_ON(p->is_write);
+
+	if (pmu_access_el0_disabled(vcpu))
+		return false;
+
+	if (!(p->Op2 & 1))
+		pmceid = read_sysreg(pmceid0_el0);
+	else
+		pmceid = read_sysreg(pmceid1_el0);
+
+	p->regval = pmceid;
+
+	return true;
+}
+
+static bool pmu_counter_idx_valid(struct kvm_vcpu *vcpu, u64 idx)
+{
+	u64 pmcr, val;
+
+	pmcr = __vcpu_sys_reg(vcpu, PMCR_EL0);
+	val = (pmcr >> ARMV8_PMU_PMCR_N_SHIFT) & ARMV8_PMU_PMCR_N_MASK;
+	if (idx >= val && idx != ARMV8_PMU_CYCLE_IDX) {
+		kvm_inject_undefined(vcpu);
+		return false;
+	}
+
+	return true;
+}
+
+static bool access_pmu_evcntr(struct kvm_vcpu *vcpu,
+			      struct sys_reg_params *p,
+			      const struct sys_reg_desc *r)
+{
+	u64 idx;
+
+	if (!kvm_arm_pmu_v3_ready(vcpu))
+		return trap_raz_wi(vcpu, p, r);
+
+	if (r->CRn == 9 && r->CRm == 13) {
+		if (r->Op2 == 2) {
+			/* PMXEVCNTR_EL0 */
+			if (pmu_access_event_counter_el0_disabled(vcpu))
+				return false;
+
+			idx = __vcpu_sys_reg(vcpu, PMSELR_EL0)
+			      & ARMV8_PMU_COUNTER_MASK;
+		} else if (r->Op2 == 0) {
+			/* PMCCNTR_EL0 */
+			if (pmu_access_cycle_counter_el0_disabled(vcpu))
+				return false;
+
+			idx = ARMV8_PMU_CYCLE_IDX;
+		} else {
+			return false;
+		}
+	} else if (r->CRn == 0 && r->CRm == 9) {
+		/* PMCCNTR */
+		if (pmu_access_event_counter_el0_disabled(vcpu))
+			return false;
+
+		idx = ARMV8_PMU_CYCLE_IDX;
+	} else if (r->CRn == 14 && (r->CRm & 12) == 8) {
+		/* PMEVCNTRn_EL0 */
+		if (pmu_access_event_counter_el0_disabled(vcpu))
+			return false;
+
+		idx = ((r->CRm & 3) << 3) | (r->Op2 & 7);
+	} else {
+		return false;
+	}
+
+	if (!pmu_counter_idx_valid(vcpu, idx))
+		return false;
+
+	if (p->is_write) {
+		if (pmu_access_el0_disabled(vcpu))
+			return false;
+
+		kvm_pmu_set_counter_value(vcpu, idx, p->regval);
+	} else {
+		p->regval = kvm_pmu_get_counter_value(vcpu, idx);
+	}
+
+	return true;
+}
+
+static bool access_pmu_evtyper(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
+			       const struct sys_reg_desc *r)
+{
+	u64 idx, reg;
+
+	if (!kvm_arm_pmu_v3_ready(vcpu))
+		return trap_raz_wi(vcpu, p, r);
+
+	if (pmu_access_el0_disabled(vcpu))
+		return false;
+
+	if (r->CRn == 9 && r->CRm == 13 && r->Op2 == 1) {
+		/* PMXEVTYPER_EL0 */
+		idx = __vcpu_sys_reg(vcpu, PMSELR_EL0) & ARMV8_PMU_COUNTER_MASK;
+		reg = PMEVTYPER0_EL0 + idx;
+	} else if (r->CRn == 14 && (r->CRm & 12) == 12) {
+		idx = ((r->CRm & 3) << 3) | (r->Op2 & 7);
+		if (idx == ARMV8_PMU_CYCLE_IDX)
+			reg = PMCCFILTR_EL0;
+		else
+			/* PMEVTYPERn_EL0 */
+			reg = PMEVTYPER0_EL0 + idx;
+	} else {
+		BUG();
+	}
+
+	if (!pmu_counter_idx_valid(vcpu, idx))
+		return false;
+
+	if (p->is_write) {
+		kvm_pmu_set_counter_event_type(vcpu, p->regval, idx);
+		__vcpu_sys_reg(vcpu, reg) = p->regval & ARMV8_PMU_EVTYPE_MASK;
+	} else {
+		p->regval = __vcpu_sys_reg(vcpu, reg) & ARMV8_PMU_EVTYPE_MASK;
+	}
+
+	return true;
+}
+
+static bool access_pmcnten(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
+			   const struct sys_reg_desc *r)
+{
+	u64 val, mask;
+
+	if (!kvm_arm_pmu_v3_ready(vcpu))
+		return trap_raz_wi(vcpu, p, r);
+
+	if (pmu_access_el0_disabled(vcpu))
+		return false;
+
+	mask = kvm_pmu_valid_counter_mask(vcpu);
+	if (p->is_write) {
+		val = p->regval & mask;
+		if (r->Op2 & 0x1) {
+			/* accessing PMCNTENSET_EL0 */
+			__vcpu_sys_reg(vcpu, PMCNTENSET_EL0) |= val;
+			kvm_pmu_enable_counter(vcpu, val);
+		} else {
+			/* accessing PMCNTENCLR_EL0 */
+			__vcpu_sys_reg(vcpu, PMCNTENSET_EL0) &= ~val;
+			kvm_pmu_disable_counter(vcpu, val);
+		}
+	} else {
+		p->regval = __vcpu_sys_reg(vcpu, PMCNTENSET_EL0) & mask;
+	}
+
+	return true;
+}
+
+static bool access_pminten(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
+			   const struct sys_reg_desc *r)
+{
+	u64 mask = kvm_pmu_valid_counter_mask(vcpu);
+
+	if (!kvm_arm_pmu_v3_ready(vcpu))
+		return trap_raz_wi(vcpu, p, r);
+
+	if (!vcpu_mode_priv(vcpu)) {
+		kvm_inject_undefined(vcpu);
+		return false;
+	}
+
+	if (p->is_write) {
+		u64 val = p->regval & mask;
+
+		if (r->Op2 & 0x1)
+			/* accessing PMINTENSET_EL1 */
+			__vcpu_sys_reg(vcpu, PMINTENSET_EL1) |= val;
+		else
+			/* accessing PMINTENCLR_EL1 */
+			__vcpu_sys_reg(vcpu, PMINTENSET_EL1) &= ~val;
+	} else {
+		p->regval = __vcpu_sys_reg(vcpu, PMINTENSET_EL1) & mask;
+	}
+
+	return true;
+}
+
+static bool access_pmovs(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
+			 const struct sys_reg_desc *r)
+{
+	u64 mask = kvm_pmu_valid_counter_mask(vcpu);
+
+	if (!kvm_arm_pmu_v3_ready(vcpu))
+		return trap_raz_wi(vcpu, p, r);
+
+	if (pmu_access_el0_disabled(vcpu))
+		return false;
+
+	if (p->is_write) {
+		if (r->CRm & 0x2)
+			/* accessing PMOVSSET_EL0 */
+			__vcpu_sys_reg(vcpu, PMOVSSET_EL0) |= (p->regval & mask);
+		else
+			/* accessing PMOVSCLR_EL0 */
+			__vcpu_sys_reg(vcpu, PMOVSSET_EL0) &= ~(p->regval & mask);
+	} else {
+		p->regval = __vcpu_sys_reg(vcpu, PMOVSSET_EL0) & mask;
+	}
+
+	return true;
+}
+
+static bool access_pmswinc(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
+			   const struct sys_reg_desc *r)
+{
+	u64 mask;
+
+	if (!kvm_arm_pmu_v3_ready(vcpu))
+		return trap_raz_wi(vcpu, p, r);
+
+	if (!p->is_write)
+		return read_from_write_only(vcpu, p, r);
+
+	if (pmu_write_swinc_el0_disabled(vcpu))
+		return false;
+
+	mask = kvm_pmu_valid_counter_mask(vcpu);
+	kvm_pmu_software_increment(vcpu, p->regval & mask);
+	return true;
+}
+
+static bool access_pmuserenr(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
+			     const struct sys_reg_desc *r)
+{
+	if (!kvm_arm_pmu_v3_ready(vcpu))
+		return trap_raz_wi(vcpu, p, r);
+
+	if (p->is_write) {
+		if (!vcpu_mode_priv(vcpu)) {
+			kvm_inject_undefined(vcpu);
+			return false;
+		}
+
+		__vcpu_sys_reg(vcpu, PMUSERENR_EL0) =
+			       p->regval & ARMV8_PMU_USERENR_MASK;
+	} else {
+		p->regval = __vcpu_sys_reg(vcpu, PMUSERENR_EL0)
+			    & ARMV8_PMU_USERENR_MASK;
+	}
+
+	return true;
+}
+
+/* Silly macro to expand the DBG{BCR,BVR,WVR,WCR}n_EL1 registers in one go */
+#define DBG_BCR_BVR_WCR_WVR_EL1(n)					\
+	{ SYS_DESC(SYS_DBGBVRn_EL1(n)),					\
+	  trap_bvr, reset_bvr, 0, 0, get_bvr, set_bvr },		\
+	{ SYS_DESC(SYS_DBGBCRn_EL1(n)),					\
+	  trap_bcr, reset_bcr, 0, 0, get_bcr, set_bcr },		\
+	{ SYS_DESC(SYS_DBGWVRn_EL1(n)),					\
+	  trap_wvr, reset_wvr, 0, 0,  get_wvr, set_wvr },		\
+	{ SYS_DESC(SYS_DBGWCRn_EL1(n)),					\
+	  trap_wcr, reset_wcr, 0, 0,  get_wcr, set_wcr }
+
+/* Macro to expand the PMEVCNTRn_EL0 register */
+#define PMU_PMEVCNTR_EL0(n)						\
+	{ SYS_DESC(SYS_PMEVCNTRn_EL0(n)),					\
+	  access_pmu_evcntr, reset_unknown, (PMEVCNTR0_EL0 + n), }
+
+/* Macro to expand the PMEVTYPERn_EL0 register */
+#define PMU_PMEVTYPER_EL0(n)						\
+	{ SYS_DESC(SYS_PMEVTYPERn_EL0(n)),					\
+	  access_pmu_evtyper, reset_unknown, (PMEVTYPER0_EL0 + n), }
+
+static bool access_cntp_tval(struct kvm_vcpu *vcpu,
+		struct sys_reg_params *p,
+		const struct sys_reg_desc *r)
+{
+	u64 now = kvm_phys_timer_read();
+	u64 cval;
+
+	if (p->is_write) {
+		kvm_arm_timer_set_reg(vcpu, KVM_REG_ARM_PTIMER_CVAL,
+				      p->regval + now);
+	} else {
+		cval = kvm_arm_timer_get_reg(vcpu, KVM_REG_ARM_PTIMER_CVAL);
+		p->regval = cval - now;
+	}
+
+	return true;
+}
+
+static bool access_cntp_ctl(struct kvm_vcpu *vcpu,
+		struct sys_reg_params *p,
+		const struct sys_reg_desc *r)
+{
+	if (p->is_write)
+		kvm_arm_timer_set_reg(vcpu, KVM_REG_ARM_PTIMER_CTL, p->regval);
+	else
+		p->regval = kvm_arm_timer_get_reg(vcpu, KVM_REG_ARM_PTIMER_CTL);
+
+	return true;
+}
+
+static bool access_cntp_cval(struct kvm_vcpu *vcpu,
+		struct sys_reg_params *p,
+		const struct sys_reg_desc *r)
+{
+	if (p->is_write)
+		kvm_arm_timer_set_reg(vcpu, KVM_REG_ARM_PTIMER_CVAL, p->regval);
+	else
+		p->regval = kvm_arm_timer_get_reg(vcpu, KVM_REG_ARM_PTIMER_CVAL);
+
+	return true;
+}
+
+/* Read a sanitised cpufeature ID register by sys_reg_desc */
+static u64 read_id_reg(struct sys_reg_desc const *r, bool raz)
+{
+	u32 id = sys_reg((u32)r->Op0, (u32)r->Op1,
+			 (u32)r->CRn, (u32)r->CRm, (u32)r->Op2);
+	u64 val = raz ? 0 : read_sanitised_ftr_reg(id);
+
+	if (id == SYS_ID_AA64PFR0_EL1) {
+		if (val & (0xfUL << ID_AA64PFR0_SVE_SHIFT))
+			kvm_debug("SVE unsupported for guests, suppressing\n");
+
+		val &= ~(0xfUL << ID_AA64PFR0_SVE_SHIFT);
+	} else if (id == SYS_ID_AA64MMFR1_EL1) {
+		if (val & (0xfUL << ID_AA64MMFR1_LOR_SHIFT))
+			kvm_debug("LORegions unsupported for guests, suppressing\n");
+
+		val &= ~(0xfUL << ID_AA64MMFR1_LOR_SHIFT);
+	}
+
+	return val;
+}
+
+/* cpufeature ID register access trap handlers */
+
+static bool __access_id_reg(struct kvm_vcpu *vcpu,
+			    struct sys_reg_params *p,
+			    const struct sys_reg_desc *r,
+			    bool raz)
+{
+	if (p->is_write)
+		return write_to_read_only(vcpu, p, r);
+
+	p->regval = read_id_reg(r, raz);
+	return true;
+}
+
+static bool access_id_reg(struct kvm_vcpu *vcpu,
+			  struct sys_reg_params *p,
+			  const struct sys_reg_desc *r)
+{
+	return __access_id_reg(vcpu, p, r, false);
+}
+
+static bool access_raz_id_reg(struct kvm_vcpu *vcpu,
+			      struct sys_reg_params *p,
+			      const struct sys_reg_desc *r)
+{
+	return __access_id_reg(vcpu, p, r, true);
+}
+
+static int reg_from_user(u64 *val, const void __user *uaddr, u64 id);
+static int reg_to_user(void __user *uaddr, const u64 *val, u64 id);
+static u64 sys_reg_to_index(const struct sys_reg_desc *reg);
+
+/*
+ * cpufeature ID register user accessors
+ *
+ * For now, these registers are immutable for userspace, so no values
+ * are stored, and for set_id_reg() we don't allow the effective value
+ * to be changed.
+ */
+static int __get_id_reg(const struct sys_reg_desc *rd, void __user *uaddr,
+			bool raz)
+{
+	const u64 id = sys_reg_to_index(rd);
+	const u64 val = read_id_reg(rd, raz);
+
+	return reg_to_user(uaddr, &val, id);
+}
+
+static int __set_id_reg(const struct sys_reg_desc *rd, void __user *uaddr,
+			bool raz)
+{
+	const u64 id = sys_reg_to_index(rd);
+	int err;
+	u64 val;
+
+	err = reg_from_user(&val, uaddr, id);
+	if (err)
+		return err;
+
+	/* This is what we mean by invariant: you can't change it. */
+	if (val != read_id_reg(rd, raz))
+		return -EINVAL;
+
+	return 0;
+}
+
+static int get_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
+		      const struct kvm_one_reg *reg, void __user *uaddr)
+{
+	return __get_id_reg(rd, uaddr, false);
+}
+
+static int set_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
+		      const struct kvm_one_reg *reg, void __user *uaddr)
+{
+	return __set_id_reg(rd, uaddr, false);
+}
+
+static int get_raz_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
+			  const struct kvm_one_reg *reg, void __user *uaddr)
+{
+	return __get_id_reg(rd, uaddr, true);
+}
+
+static int set_raz_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
+			  const struct kvm_one_reg *reg, void __user *uaddr)
+{
+	return __set_id_reg(rd, uaddr, true);
+}
+
+/* sys_reg_desc initialiser for known cpufeature ID registers */
+#define ID_SANITISED(name) {			\
+	SYS_DESC(SYS_##name),			\
+	.access	= access_id_reg,		\
+	.get_user = get_id_reg,			\
+	.set_user = set_id_reg,			\
+}
+
+/*
+ * sys_reg_desc initialiser for architecturally unallocated cpufeature ID
+ * register with encoding Op0=3, Op1=0, CRn=0, CRm=crm, Op2=op2
+ * (1 <= crm < 8, 0 <= Op2 < 8).
+ */
+#define ID_UNALLOCATED(crm, op2) {			\
+	Op0(3), Op1(0), CRn(0), CRm(crm), Op2(op2),	\
+	.access = access_raz_id_reg,			\
+	.get_user = get_raz_id_reg,			\
+	.set_user = set_raz_id_reg,			\
+}
+
+/*
+ * sys_reg_desc initialiser for known ID registers that we hide from guests.
+ * For now, these are exposed just like unallocated ID regs: they appear
+ * RAZ for the guest.
+ */
+#define ID_HIDDEN(name) {			\
+	SYS_DESC(SYS_##name),			\
+	.access = access_raz_id_reg,		\
+	.get_user = get_raz_id_reg,		\
+	.set_user = set_raz_id_reg,		\
+}
+
+/*
+ * Architected system registers.
+ * Important: Must be sorted ascending by Op0, Op1, CRn, CRm, Op2
+ *
+ * Debug handling: We do trap most, if not all debug related system
+ * registers. The implementation is good enough to ensure that a guest
+ * can use these with minimal performance degradation. The drawback is
+ * that we don't implement any of the external debug, none of the
+ * OSlock protocol. This should be revisited if we ever encounter a
+ * more demanding guest...
+ */
+static const struct sys_reg_desc sys_reg_descs[] = {
+	{ SYS_DESC(SYS_DC_ISW), access_dcsw },
+	{ SYS_DESC(SYS_DC_CSW), access_dcsw },
+	{ SYS_DESC(SYS_DC_CISW), access_dcsw },
+
+	DBG_BCR_BVR_WCR_WVR_EL1(0),
+	DBG_BCR_BVR_WCR_WVR_EL1(1),
+	{ SYS_DESC(SYS_MDCCINT_EL1), trap_debug_regs, reset_val, MDCCINT_EL1, 0 },
+	{ SYS_DESC(SYS_MDSCR_EL1), trap_debug_regs, reset_val, MDSCR_EL1, 0 },
+	DBG_BCR_BVR_WCR_WVR_EL1(2),
+	DBG_BCR_BVR_WCR_WVR_EL1(3),
+	DBG_BCR_BVR_WCR_WVR_EL1(4),
+	DBG_BCR_BVR_WCR_WVR_EL1(5),
+	DBG_BCR_BVR_WCR_WVR_EL1(6),
+	DBG_BCR_BVR_WCR_WVR_EL1(7),
+	DBG_BCR_BVR_WCR_WVR_EL1(8),
+	DBG_BCR_BVR_WCR_WVR_EL1(9),
+	DBG_BCR_BVR_WCR_WVR_EL1(10),
+	DBG_BCR_BVR_WCR_WVR_EL1(11),
+	DBG_BCR_BVR_WCR_WVR_EL1(12),
+	DBG_BCR_BVR_WCR_WVR_EL1(13),
+	DBG_BCR_BVR_WCR_WVR_EL1(14),
+	DBG_BCR_BVR_WCR_WVR_EL1(15),
+
+	{ SYS_DESC(SYS_MDRAR_EL1), trap_raz_wi },
+	{ SYS_DESC(SYS_OSLAR_EL1), trap_raz_wi },
+	{ SYS_DESC(SYS_OSLSR_EL1), trap_oslsr_el1 },
+	{ SYS_DESC(SYS_OSDLR_EL1), trap_raz_wi },
+	{ SYS_DESC(SYS_DBGPRCR_EL1), trap_raz_wi },
+	{ SYS_DESC(SYS_DBGCLAIMSET_EL1), trap_raz_wi },
+	{ SYS_DESC(SYS_DBGCLAIMCLR_EL1), trap_raz_wi },
+	{ SYS_DESC(SYS_DBGAUTHSTATUS_EL1), trap_dbgauthstatus_el1 },
+
+	{ SYS_DESC(SYS_MDCCSR_EL0), trap_raz_wi },
+	{ SYS_DESC(SYS_DBGDTR_EL0), trap_raz_wi },
+	// DBGDTR[TR]X_EL0 share the same encoding
+	{ SYS_DESC(SYS_DBGDTRTX_EL0), trap_raz_wi },
+
+	{ SYS_DESC(SYS_DBGVCR32_EL2), NULL, reset_val, DBGVCR32_EL2, 0 },
+
+	{ SYS_DESC(SYS_MPIDR_EL1), NULL, reset_mpidr, MPIDR_EL1 },
+
+	/*
+	 * ID regs: all ID_SANITISED() entries here must have corresponding
+	 * entries in arm64_ftr_regs[].
+	 */
+
+	/* AArch64 mappings of the AArch32 ID registers */
+	/* CRm=1 */
+	ID_SANITISED(ID_PFR0_EL1),
+	ID_SANITISED(ID_PFR1_EL1),
+	ID_SANITISED(ID_DFR0_EL1),
+	ID_HIDDEN(ID_AFR0_EL1),
+	ID_SANITISED(ID_MMFR0_EL1),
+	ID_SANITISED(ID_MMFR1_EL1),
+	ID_SANITISED(ID_MMFR2_EL1),
+	ID_SANITISED(ID_MMFR3_EL1),
+
+	/* CRm=2 */
+	ID_SANITISED(ID_ISAR0_EL1),
+	ID_SANITISED(ID_ISAR1_EL1),
+	ID_SANITISED(ID_ISAR2_EL1),
+	ID_SANITISED(ID_ISAR3_EL1),
+	ID_SANITISED(ID_ISAR4_EL1),
+	ID_SANITISED(ID_ISAR5_EL1),
+	ID_SANITISED(ID_MMFR4_EL1),
+	ID_UNALLOCATED(2,7),
+
+	/* CRm=3 */
+	ID_SANITISED(MVFR0_EL1),
+	ID_SANITISED(MVFR1_EL1),
+	ID_SANITISED(MVFR2_EL1),
+	ID_UNALLOCATED(3,3),
+	ID_UNALLOCATED(3,4),
+	ID_UNALLOCATED(3,5),
+	ID_UNALLOCATED(3,6),
+	ID_UNALLOCATED(3,7),
+
+	/* AArch64 ID registers */
+	/* CRm=4 */
+	ID_SANITISED(ID_AA64PFR0_EL1),
+	ID_SANITISED(ID_AA64PFR1_EL1),
+	ID_UNALLOCATED(4,2),
+	ID_UNALLOCATED(4,3),
+	ID_UNALLOCATED(4,4),
+	ID_UNALLOCATED(4,5),
+	ID_UNALLOCATED(4,6),
+	ID_UNALLOCATED(4,7),
+
+	/* CRm=5 */
+	ID_SANITISED(ID_AA64DFR0_EL1),
+	ID_SANITISED(ID_AA64DFR1_EL1),
+	ID_UNALLOCATED(5,2),
+	ID_UNALLOCATED(5,3),
+	ID_HIDDEN(ID_AA64AFR0_EL1),
+	ID_HIDDEN(ID_AA64AFR1_EL1),
+	ID_UNALLOCATED(5,6),
+	ID_UNALLOCATED(5,7),
+
+	/* CRm=6 */
+	ID_SANITISED(ID_AA64ISAR0_EL1),
+	ID_SANITISED(ID_AA64ISAR1_EL1),
+	ID_SANITISED(ID_AA64ISAR2_EL1),
+	ID_UNALLOCATED(6,3),
+	ID_UNALLOCATED(6,4),
+	ID_UNALLOCATED(6,5),
+	ID_UNALLOCATED(6,6),
+	ID_UNALLOCATED(6,7),
+
+	/* CRm=7 */
+	ID_SANITISED(ID_AA64MMFR0_EL1),
+	ID_SANITISED(ID_AA64MMFR1_EL1),
+	ID_SANITISED(ID_AA64MMFR2_EL1),
+	ID_UNALLOCATED(7,3),
+	ID_UNALLOCATED(7,4),
+	ID_UNALLOCATED(7,5),
+	ID_UNALLOCATED(7,6),
+	ID_UNALLOCATED(7,7),
+
+	{ SYS_DESC(SYS_SCTLR_EL1), access_vm_reg, reset_val, SCTLR_EL1, 0x00C50078 },
+	{ SYS_DESC(SYS_CPACR_EL1), NULL, reset_val, CPACR_EL1, 0 },
+	{ SYS_DESC(SYS_TTBR0_EL1), access_vm_reg, reset_unknown, TTBR0_EL1 },
+	{ SYS_DESC(SYS_TTBR1_EL1), access_vm_reg, reset_unknown, TTBR1_EL1 },
+	{ SYS_DESC(SYS_TCR_EL1), access_vm_reg, reset_val, TCR_EL1, 0 },
+
+	{ SYS_DESC(SYS_AFSR0_EL1), access_vm_reg, reset_unknown, AFSR0_EL1 },
+	{ SYS_DESC(SYS_AFSR1_EL1), access_vm_reg, reset_unknown, AFSR1_EL1 },
+	{ SYS_DESC(SYS_ESR_EL1), access_vm_reg, reset_unknown, ESR_EL1 },
+
+	{ SYS_DESC(SYS_ERRIDR_EL1), trap_raz_wi },
+	{ SYS_DESC(SYS_ERRSELR_EL1), trap_raz_wi },
+	{ SYS_DESC(SYS_ERXFR_EL1), trap_raz_wi },
+	{ SYS_DESC(SYS_ERXCTLR_EL1), trap_raz_wi },
+	{ SYS_DESC(SYS_ERXSTATUS_EL1), trap_raz_wi },
+	{ SYS_DESC(SYS_ERXADDR_EL1), trap_raz_wi },
+	{ SYS_DESC(SYS_ERXMISC0_EL1), trap_raz_wi },
+	{ SYS_DESC(SYS_ERXMISC1_EL1), trap_raz_wi },
+
+	{ SYS_DESC(SYS_FAR_EL1), access_vm_reg, reset_unknown, FAR_EL1 },
+	{ SYS_DESC(SYS_PAR_EL1), NULL, reset_unknown, PAR_EL1 },
+
+	{ SYS_DESC(SYS_PMINTENSET_EL1), access_pminten, reset_unknown, PMINTENSET_EL1 },
+	{ SYS_DESC(SYS_PMINTENCLR_EL1), access_pminten, NULL, PMINTENSET_EL1 },
+
+	{ SYS_DESC(SYS_MAIR_EL1), access_vm_reg, reset_unknown, MAIR_EL1 },
+	{ SYS_DESC(SYS_AMAIR_EL1), access_vm_reg, reset_amair_el1, AMAIR_EL1 },
+
+	{ SYS_DESC(SYS_LORSA_EL1), trap_undef },
+	{ SYS_DESC(SYS_LOREA_EL1), trap_undef },
+	{ SYS_DESC(SYS_LORN_EL1), trap_undef },
+	{ SYS_DESC(SYS_LORC_EL1), trap_undef },
+	{ SYS_DESC(SYS_LORID_EL1), trap_undef },
+
+	{ SYS_DESC(SYS_VBAR_EL1), NULL, reset_val, VBAR_EL1, 0 },
+	{ SYS_DESC(SYS_DISR_EL1), NULL, reset_val, DISR_EL1, 0 },
+
+	{ SYS_DESC(SYS_ICC_IAR0_EL1), write_to_read_only },
+	{ SYS_DESC(SYS_ICC_EOIR0_EL1), read_from_write_only },
+	{ SYS_DESC(SYS_ICC_HPPIR0_EL1), write_to_read_only },
+	{ SYS_DESC(SYS_ICC_DIR_EL1), read_from_write_only },
+	{ SYS_DESC(SYS_ICC_RPR_EL1), write_to_read_only },
+	{ SYS_DESC(SYS_ICC_SGI1R_EL1), access_gic_sgi },
+	{ SYS_DESC(SYS_ICC_ASGI1R_EL1), access_gic_sgi },
+	{ SYS_DESC(SYS_ICC_SGI0R_EL1), access_gic_sgi },
+	{ SYS_DESC(SYS_ICC_IAR1_EL1), write_to_read_only },
+	{ SYS_DESC(SYS_ICC_EOIR1_EL1), read_from_write_only },
+	{ SYS_DESC(SYS_ICC_HPPIR1_EL1), write_to_read_only },
+	{ SYS_DESC(SYS_ICC_SRE_EL1), access_gic_sre },
+
+	{ SYS_DESC(SYS_CONTEXTIDR_EL1), access_vm_reg, reset_val, CONTEXTIDR_EL1, 0 },
+	{ SYS_DESC(SYS_TPIDR_EL1), NULL, reset_unknown, TPIDR_EL1 },
+
+	{ SYS_DESC(SYS_CNTKCTL_EL1), NULL, reset_val, CNTKCTL_EL1, 0},
+
+	{ SYS_DESC(SYS_CSSELR_EL1), NULL, reset_unknown, CSSELR_EL1 },
+
+	{ SYS_DESC(SYS_PMCR_EL0), access_pmcr, reset_pmcr, PMCR_EL0 },
+	{ SYS_DESC(SYS_PMCNTENSET_EL0), access_pmcnten, reset_unknown, PMCNTENSET_EL0 },
+	{ SYS_DESC(SYS_PMCNTENCLR_EL0), access_pmcnten, NULL, PMCNTENSET_EL0 },
+	{ SYS_DESC(SYS_PMOVSCLR_EL0), access_pmovs, NULL, PMOVSSET_EL0 },
+	{ SYS_DESC(SYS_PMSWINC_EL0), access_pmswinc, reset_unknown, PMSWINC_EL0 },
+	{ SYS_DESC(SYS_PMSELR_EL0), access_pmselr, reset_unknown, PMSELR_EL0 },
+	{ SYS_DESC(SYS_PMCEID0_EL0), access_pmceid },
+	{ SYS_DESC(SYS_PMCEID1_EL0), access_pmceid },
+	{ SYS_DESC(SYS_PMCCNTR_EL0), access_pmu_evcntr, reset_unknown, PMCCNTR_EL0 },
+	{ SYS_DESC(SYS_PMXEVTYPER_EL0), access_pmu_evtyper },
+	{ SYS_DESC(SYS_PMXEVCNTR_EL0), access_pmu_evcntr },
+	/*
+	 * PMUSERENR_EL0 resets as unknown in 64bit mode while it resets as zero
+	 * in 32bit mode. Here we choose to reset it as zero for consistency.
+	 */
+	{ SYS_DESC(SYS_PMUSERENR_EL0), access_pmuserenr, reset_val, PMUSERENR_EL0, 0 },
+	{ SYS_DESC(SYS_PMOVSSET_EL0), access_pmovs, reset_unknown, PMOVSSET_EL0 },
+
+	{ SYS_DESC(SYS_TPIDR_EL0), NULL, reset_unknown, TPIDR_EL0 },
+	{ SYS_DESC(SYS_TPIDRRO_EL0), NULL, reset_unknown, TPIDRRO_EL0 },
+
+	{ SYS_DESC(SYS_CNTP_TVAL_EL0), access_cntp_tval },
+	{ SYS_DESC(SYS_CNTP_CTL_EL0), access_cntp_ctl },
+	{ SYS_DESC(SYS_CNTP_CVAL_EL0), access_cntp_cval },
+
+	/* PMEVCNTRn_EL0 */
+	PMU_PMEVCNTR_EL0(0),
+	PMU_PMEVCNTR_EL0(1),
+	PMU_PMEVCNTR_EL0(2),
+	PMU_PMEVCNTR_EL0(3),
+	PMU_PMEVCNTR_EL0(4),
+	PMU_PMEVCNTR_EL0(5),
+	PMU_PMEVCNTR_EL0(6),
+	PMU_PMEVCNTR_EL0(7),
+	PMU_PMEVCNTR_EL0(8),
+	PMU_PMEVCNTR_EL0(9),
+	PMU_PMEVCNTR_EL0(10),
+	PMU_PMEVCNTR_EL0(11),
+	PMU_PMEVCNTR_EL0(12),
+	PMU_PMEVCNTR_EL0(13),
+	PMU_PMEVCNTR_EL0(14),
+	PMU_PMEVCNTR_EL0(15),
+	PMU_PMEVCNTR_EL0(16),
+	PMU_PMEVCNTR_EL0(17),
+	PMU_PMEVCNTR_EL0(18),
+	PMU_PMEVCNTR_EL0(19),
+	PMU_PMEVCNTR_EL0(20),
+	PMU_PMEVCNTR_EL0(21),
+	PMU_PMEVCNTR_EL0(22),
+	PMU_PMEVCNTR_EL0(23),
+	PMU_PMEVCNTR_EL0(24),
+	PMU_PMEVCNTR_EL0(25),
+	PMU_PMEVCNTR_EL0(26),
+	PMU_PMEVCNTR_EL0(27),
+	PMU_PMEVCNTR_EL0(28),
+	PMU_PMEVCNTR_EL0(29),
+	PMU_PMEVCNTR_EL0(30),
+	/* PMEVTYPERn_EL0 */
+	PMU_PMEVTYPER_EL0(0),
+	PMU_PMEVTYPER_EL0(1),
+	PMU_PMEVTYPER_EL0(2),
+	PMU_PMEVTYPER_EL0(3),
+	PMU_PMEVTYPER_EL0(4),
+	PMU_PMEVTYPER_EL0(5),
+	PMU_PMEVTYPER_EL0(6),
+	PMU_PMEVTYPER_EL0(7),
+	PMU_PMEVTYPER_EL0(8),
+	PMU_PMEVTYPER_EL0(9),
+	PMU_PMEVTYPER_EL0(10),
+	PMU_PMEVTYPER_EL0(11),
+	PMU_PMEVTYPER_EL0(12),
+	PMU_PMEVTYPER_EL0(13),
+	PMU_PMEVTYPER_EL0(14),
+	PMU_PMEVTYPER_EL0(15),
+	PMU_PMEVTYPER_EL0(16),
+	PMU_PMEVTYPER_EL0(17),
+	PMU_PMEVTYPER_EL0(18),
+	PMU_PMEVTYPER_EL0(19),
+	PMU_PMEVTYPER_EL0(20),
+	PMU_PMEVTYPER_EL0(21),
+	PMU_PMEVTYPER_EL0(22),
+	PMU_PMEVTYPER_EL0(23),
+	PMU_PMEVTYPER_EL0(24),
+	PMU_PMEVTYPER_EL0(25),
+	PMU_PMEVTYPER_EL0(26),
+	PMU_PMEVTYPER_EL0(27),
+	PMU_PMEVTYPER_EL0(28),
+	PMU_PMEVTYPER_EL0(29),
+	PMU_PMEVTYPER_EL0(30),
+	/*
+	 * PMCCFILTR_EL0 resets as unknown in 64bit mode while it resets as zero
+	 * in 32bit mode. Here we choose to reset it as zero for consistency.
+	 */
+	{ SYS_DESC(SYS_PMCCFILTR_EL0), access_pmu_evtyper, reset_val, PMCCFILTR_EL0, 0 },
+
+	{ SYS_DESC(SYS_DACR32_EL2), NULL, reset_unknown, DACR32_EL2 },
+	{ SYS_DESC(SYS_IFSR32_EL2), NULL, reset_unknown, IFSR32_EL2 },
+	{ SYS_DESC(SYS_FPEXC32_EL2), NULL, reset_val, FPEXC32_EL2, 0x700 },
+};
+
+static bool trap_dbgidr(struct kvm_vcpu *vcpu,
+			struct sys_reg_params *p,
+			const struct sys_reg_desc *r)
+{
+	if (p->is_write) {
+		return ignore_write(vcpu, p);
+	} else {
+		u64 dfr = read_sanitised_ftr_reg(SYS_ID_AA64DFR0_EL1);
+		u64 pfr = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
+		u32 el3 = !!cpuid_feature_extract_unsigned_field(pfr, ID_AA64PFR0_EL3_SHIFT);
+
+		p->regval = ((((dfr >> ID_AA64DFR0_WRPS_SHIFT) & 0xf) << 28) |
+			     (((dfr >> ID_AA64DFR0_BRPS_SHIFT) & 0xf) << 24) |
+			     (((dfr >> ID_AA64DFR0_CTX_CMPS_SHIFT) & 0xf) << 20)
+			     | (6 << 16) | (el3 << 14) | (el3 << 12));
+		return true;
+	}
+}
+
+static bool trap_debug32(struct kvm_vcpu *vcpu,
+			 struct sys_reg_params *p,
+			 const struct sys_reg_desc *r)
+{
+	if (p->is_write) {
+		vcpu_cp14(vcpu, r->reg) = p->regval;
+		vcpu->arch.flags |= KVM_ARM64_DEBUG_DIRTY;
+	} else {
+		p->regval = vcpu_cp14(vcpu, r->reg);
+	}
+
+	return true;
+}
+
+/* AArch32 debug register mappings
+ *
+ * AArch32 DBGBVRn is mapped to DBGBVRn_EL1[31:0]
+ * AArch32 DBGBXVRn is mapped to DBGBVRn_EL1[63:32]
+ *
+ * All control registers and watchpoint value registers are mapped to
+ * the lower 32 bits of their AArch64 equivalents. We share the trap
+ * handlers with the above AArch64 code which checks what mode the
+ * system is in.
+ */
+
+static bool trap_xvr(struct kvm_vcpu *vcpu,
+		     struct sys_reg_params *p,
+		     const struct sys_reg_desc *rd)
+{
+	u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg];
+
+	if (p->is_write) {
+		u64 val = *dbg_reg;
+
+		val &= 0xffffffffUL;
+		val |= p->regval << 32;
+		*dbg_reg = val;
+
+		vcpu->arch.flags |= KVM_ARM64_DEBUG_DIRTY;
+	} else {
+		p->regval = *dbg_reg >> 32;
+	}
+
+	trace_trap_reg(__func__, rd->reg, p->is_write, *dbg_reg);
+
+	return true;
+}
+
+#define DBG_BCR_BVR_WCR_WVR(n)						\
+	/* DBGBVRn */							\
+	{ Op1( 0), CRn( 0), CRm((n)), Op2( 4), trap_bvr, NULL, n }, 	\
+	/* DBGBCRn */							\
+	{ Op1( 0), CRn( 0), CRm((n)), Op2( 5), trap_bcr, NULL, n },	\
+	/* DBGWVRn */							\
+	{ Op1( 0), CRn( 0), CRm((n)), Op2( 6), trap_wvr, NULL, n },	\
+	/* DBGWCRn */							\
+	{ Op1( 0), CRn( 0), CRm((n)), Op2( 7), trap_wcr, NULL, n }
+
+#define DBGBXVR(n)							\
+	{ Op1( 0), CRn( 1), CRm((n)), Op2( 1), trap_xvr, NULL, n }
+
+/*
+ * Trapped cp14 registers. We generally ignore most of the external
+ * debug, on the principle that they don't really make sense to a
+ * guest. Revisit this one day, would this principle change.
+ */
+static const struct sys_reg_desc cp14_regs[] = {
+	/* DBGIDR */
+	{ Op1( 0), CRn( 0), CRm( 0), Op2( 0), trap_dbgidr },
+	/* DBGDTRRXext */
+	{ Op1( 0), CRn( 0), CRm( 0), Op2( 2), trap_raz_wi },
+
+	DBG_BCR_BVR_WCR_WVR(0),
+	/* DBGDSCRint */
+	{ Op1( 0), CRn( 0), CRm( 1), Op2( 0), trap_raz_wi },
+	DBG_BCR_BVR_WCR_WVR(1),
+	/* DBGDCCINT */
+	{ Op1( 0), CRn( 0), CRm( 2), Op2( 0), trap_debug32, NULL, cp14_DBGDCCINT },
+	/* DBGDSCRext */
+	{ Op1( 0), CRn( 0), CRm( 2), Op2( 2), trap_debug32, NULL, cp14_DBGDSCRext },
+	DBG_BCR_BVR_WCR_WVR(2),
+	/* DBGDTR[RT]Xint */
+	{ Op1( 0), CRn( 0), CRm( 3), Op2( 0), trap_raz_wi },
+	/* DBGDTR[RT]Xext */
+	{ Op1( 0), CRn( 0), CRm( 3), Op2( 2), trap_raz_wi },
+	DBG_BCR_BVR_WCR_WVR(3),
+	DBG_BCR_BVR_WCR_WVR(4),
+	DBG_BCR_BVR_WCR_WVR(5),
+	/* DBGWFAR */
+	{ Op1( 0), CRn( 0), CRm( 6), Op2( 0), trap_raz_wi },
+	/* DBGOSECCR */
+	{ Op1( 0), CRn( 0), CRm( 6), Op2( 2), trap_raz_wi },
+	DBG_BCR_BVR_WCR_WVR(6),
+	/* DBGVCR */
+	{ Op1( 0), CRn( 0), CRm( 7), Op2( 0), trap_debug32, NULL, cp14_DBGVCR },
+	DBG_BCR_BVR_WCR_WVR(7),
+	DBG_BCR_BVR_WCR_WVR(8),
+	DBG_BCR_BVR_WCR_WVR(9),
+	DBG_BCR_BVR_WCR_WVR(10),
+	DBG_BCR_BVR_WCR_WVR(11),
+	DBG_BCR_BVR_WCR_WVR(12),
+	DBG_BCR_BVR_WCR_WVR(13),
+	DBG_BCR_BVR_WCR_WVR(14),
+	DBG_BCR_BVR_WCR_WVR(15),
+
+	/* DBGDRAR (32bit) */
+	{ Op1( 0), CRn( 1), CRm( 0), Op2( 0), trap_raz_wi },
+
+	DBGBXVR(0),
+	/* DBGOSLAR */
+	{ Op1( 0), CRn( 1), CRm( 0), Op2( 4), trap_raz_wi },
+	DBGBXVR(1),
+	/* DBGOSLSR */
+	{ Op1( 0), CRn( 1), CRm( 1), Op2( 4), trap_oslsr_el1 },
+	DBGBXVR(2),
+	DBGBXVR(3),
+	/* DBGOSDLR */
+	{ Op1( 0), CRn( 1), CRm( 3), Op2( 4), trap_raz_wi },
+	DBGBXVR(4),
+	/* DBGPRCR */
+	{ Op1( 0), CRn( 1), CRm( 4), Op2( 4), trap_raz_wi },
+	DBGBXVR(5),
+	DBGBXVR(6),
+	DBGBXVR(7),
+	DBGBXVR(8),
+	DBGBXVR(9),
+	DBGBXVR(10),
+	DBGBXVR(11),
+	DBGBXVR(12),
+	DBGBXVR(13),
+	DBGBXVR(14),
+	DBGBXVR(15),
+
+	/* DBGDSAR (32bit) */
+	{ Op1( 0), CRn( 2), CRm( 0), Op2( 0), trap_raz_wi },
+
+	/* DBGDEVID2 */
+	{ Op1( 0), CRn( 7), CRm( 0), Op2( 7), trap_raz_wi },
+	/* DBGDEVID1 */
+	{ Op1( 0), CRn( 7), CRm( 1), Op2( 7), trap_raz_wi },
+	/* DBGDEVID */
+	{ Op1( 0), CRn( 7), CRm( 2), Op2( 7), trap_raz_wi },
+	/* DBGCLAIMSET */
+	{ Op1( 0), CRn( 7), CRm( 8), Op2( 6), trap_raz_wi },
+	/* DBGCLAIMCLR */
+	{ Op1( 0), CRn( 7), CRm( 9), Op2( 6), trap_raz_wi },
+	/* DBGAUTHSTATUS */
+	{ Op1( 0), CRn( 7), CRm(14), Op2( 6), trap_dbgauthstatus_el1 },
+};
+
+/* Trapped cp14 64bit registers */
+static const struct sys_reg_desc cp14_64_regs[] = {
+	/* DBGDRAR (64bit) */
+	{ Op1( 0), CRm( 1), .access = trap_raz_wi },
+
+	/* DBGDSAR (64bit) */
+	{ Op1( 0), CRm( 2), .access = trap_raz_wi },
+};
+
+/* Macro to expand the PMEVCNTRn register */
+#define PMU_PMEVCNTR(n)							\
+	/* PMEVCNTRn */							\
+	{ Op1(0), CRn(0b1110),						\
+	  CRm((0b1000 | (((n) >> 3) & 0x3))), Op2(((n) & 0x7)),		\
+	  access_pmu_evcntr }
+
+/* Macro to expand the PMEVTYPERn register */
+#define PMU_PMEVTYPER(n)						\
+	/* PMEVTYPERn */						\
+	{ Op1(0), CRn(0b1110),						\
+	  CRm((0b1100 | (((n) >> 3) & 0x3))), Op2(((n) & 0x7)),		\
+	  access_pmu_evtyper }
+
+/*
+ * Trapped cp15 registers. TTBR0/TTBR1 get a double encoding,
+ * depending on the way they are accessed (as a 32bit or a 64bit
+ * register).
+ */
+static const struct sys_reg_desc cp15_regs[] = {
+	{ Op1( 0), CRn( 1), CRm( 0), Op2( 0), access_vm_reg, NULL, c1_SCTLR },
+	{ Op1( 0), CRn( 2), CRm( 0), Op2( 0), access_vm_reg, NULL, c2_TTBR0 },
+	{ Op1( 0), CRn( 2), CRm( 0), Op2( 1), access_vm_reg, NULL, c2_TTBR1 },
+	{ Op1( 0), CRn( 2), CRm( 0), Op2( 2), access_vm_reg, NULL, c2_TTBCR },
+	{ Op1( 0), CRn( 2), CRm( 0), Op2( 3), access_vm_reg, NULL, c2_TTBCR2 },
+	{ Op1( 0), CRn( 3), CRm( 0), Op2( 0), access_vm_reg, NULL, c3_DACR },
+	{ Op1( 0), CRn( 5), CRm( 0), Op2( 0), access_vm_reg, NULL, c5_DFSR },
+	{ Op1( 0), CRn( 5), CRm( 0), Op2( 1), access_vm_reg, NULL, c5_IFSR },
+	{ Op1( 0), CRn( 5), CRm( 1), Op2( 0), access_vm_reg, NULL, c5_ADFSR },
+	{ Op1( 0), CRn( 5), CRm( 1), Op2( 1), access_vm_reg, NULL, c5_AIFSR },
+	{ Op1( 0), CRn( 6), CRm( 0), Op2( 0), access_vm_reg, NULL, c6_DFAR },
+	{ Op1( 0), CRn( 6), CRm( 0), Op2( 2), access_vm_reg, NULL, c6_IFAR },
+
+	/*
+	 * DC{C,I,CI}SW operations:
+	 */
+	{ Op1( 0), CRn( 7), CRm( 6), Op2( 2), access_dcsw },
+	{ Op1( 0), CRn( 7), CRm(10), Op2( 2), access_dcsw },
+	{ Op1( 0), CRn( 7), CRm(14), Op2( 2), access_dcsw },
+
+	/* PMU */
+	{ Op1( 0), CRn( 9), CRm(12), Op2( 0), access_pmcr },
+	{ Op1( 0), CRn( 9), CRm(12), Op2( 1), access_pmcnten },
+	{ Op1( 0), CRn( 9), CRm(12), Op2( 2), access_pmcnten },
+	{ Op1( 0), CRn( 9), CRm(12), Op2( 3), access_pmovs },
+	{ Op1( 0), CRn( 9), CRm(12), Op2( 4), access_pmswinc },
+	{ Op1( 0), CRn( 9), CRm(12), Op2( 5), access_pmselr },
+	{ Op1( 0), CRn( 9), CRm(12), Op2( 6), access_pmceid },
+	{ Op1( 0), CRn( 9), CRm(12), Op2( 7), access_pmceid },
+	{ Op1( 0), CRn( 9), CRm(13), Op2( 0), access_pmu_evcntr },
+	{ Op1( 0), CRn( 9), CRm(13), Op2( 1), access_pmu_evtyper },
+	{ Op1( 0), CRn( 9), CRm(13), Op2( 2), access_pmu_evcntr },
+	{ Op1( 0), CRn( 9), CRm(14), Op2( 0), access_pmuserenr },
+	{ Op1( 0), CRn( 9), CRm(14), Op2( 1), access_pminten },
+	{ Op1( 0), CRn( 9), CRm(14), Op2( 2), access_pminten },
+	{ Op1( 0), CRn( 9), CRm(14), Op2( 3), access_pmovs },
+
+	{ Op1( 0), CRn(10), CRm( 2), Op2( 0), access_vm_reg, NULL, c10_PRRR },
+	{ Op1( 0), CRn(10), CRm( 2), Op2( 1), access_vm_reg, NULL, c10_NMRR },
+	{ Op1( 0), CRn(10), CRm( 3), Op2( 0), access_vm_reg, NULL, c10_AMAIR0 },
+	{ Op1( 0), CRn(10), CRm( 3), Op2( 1), access_vm_reg, NULL, c10_AMAIR1 },
+
+	/* ICC_SRE */
+	{ Op1( 0), CRn(12), CRm(12), Op2( 5), access_gic_sre },
+
+	{ Op1( 0), CRn(13), CRm( 0), Op2( 1), access_vm_reg, NULL, c13_CID },
+
+	/* CNTP_TVAL */
+	{ Op1( 0), CRn(14), CRm( 2), Op2( 0), access_cntp_tval },
+	/* CNTP_CTL */
+	{ Op1( 0), CRn(14), CRm( 2), Op2( 1), access_cntp_ctl },
+
+	/* PMEVCNTRn */
+	PMU_PMEVCNTR(0),
+	PMU_PMEVCNTR(1),
+	PMU_PMEVCNTR(2),
+	PMU_PMEVCNTR(3),
+	PMU_PMEVCNTR(4),
+	PMU_PMEVCNTR(5),
+	PMU_PMEVCNTR(6),
+	PMU_PMEVCNTR(7),
+	PMU_PMEVCNTR(8),
+	PMU_PMEVCNTR(9),
+	PMU_PMEVCNTR(10),
+	PMU_PMEVCNTR(11),
+	PMU_PMEVCNTR(12),
+	PMU_PMEVCNTR(13),
+	PMU_PMEVCNTR(14),
+	PMU_PMEVCNTR(15),
+	PMU_PMEVCNTR(16),
+	PMU_PMEVCNTR(17),
+	PMU_PMEVCNTR(18),
+	PMU_PMEVCNTR(19),
+	PMU_PMEVCNTR(20),
+	PMU_PMEVCNTR(21),
+	PMU_PMEVCNTR(22),
+	PMU_PMEVCNTR(23),
+	PMU_PMEVCNTR(24),
+	PMU_PMEVCNTR(25),
+	PMU_PMEVCNTR(26),
+	PMU_PMEVCNTR(27),
+	PMU_PMEVCNTR(28),
+	PMU_PMEVCNTR(29),
+	PMU_PMEVCNTR(30),
+	/* PMEVTYPERn */
+	PMU_PMEVTYPER(0),
+	PMU_PMEVTYPER(1),
+	PMU_PMEVTYPER(2),
+	PMU_PMEVTYPER(3),
+	PMU_PMEVTYPER(4),
+	PMU_PMEVTYPER(5),
+	PMU_PMEVTYPER(6),
+	PMU_PMEVTYPER(7),
+	PMU_PMEVTYPER(8),
+	PMU_PMEVTYPER(9),
+	PMU_PMEVTYPER(10),
+	PMU_PMEVTYPER(11),
+	PMU_PMEVTYPER(12),
+	PMU_PMEVTYPER(13),
+	PMU_PMEVTYPER(14),
+	PMU_PMEVTYPER(15),
+	PMU_PMEVTYPER(16),
+	PMU_PMEVTYPER(17),
+	PMU_PMEVTYPER(18),
+	PMU_PMEVTYPER(19),
+	PMU_PMEVTYPER(20),
+	PMU_PMEVTYPER(21),
+	PMU_PMEVTYPER(22),
+	PMU_PMEVTYPER(23),
+	PMU_PMEVTYPER(24),
+	PMU_PMEVTYPER(25),
+	PMU_PMEVTYPER(26),
+	PMU_PMEVTYPER(27),
+	PMU_PMEVTYPER(28),
+	PMU_PMEVTYPER(29),
+	PMU_PMEVTYPER(30),
+	/* PMCCFILTR */
+	{ Op1(0), CRn(14), CRm(15), Op2(7), access_pmu_evtyper },
+};
+
+static const struct sys_reg_desc cp15_64_regs[] = {
+	{ Op1( 0), CRn( 0), CRm( 2), Op2( 0), access_vm_reg, NULL, c2_TTBR0 },
+	{ Op1( 0), CRn( 0), CRm( 9), Op2( 0), access_pmu_evcntr },
+	{ Op1( 0), CRn( 0), CRm(12), Op2( 0), access_gic_sgi }, /* ICC_SGI1R */
+	{ Op1( 1), CRn( 0), CRm( 2), Op2( 0), access_vm_reg, NULL, c2_TTBR1 },
+	{ Op1( 1), CRn( 0), CRm(12), Op2( 0), access_gic_sgi }, /* ICC_ASGI1R */
+	{ Op1( 2), CRn( 0), CRm(12), Op2( 0), access_gic_sgi }, /* ICC_SGI0R */
+	{ Op1( 2), CRn( 0), CRm(14), Op2( 0), access_cntp_cval },
+};
+
+/* Target specific emulation tables */
+static struct kvm_sys_reg_target_table *target_tables[KVM_ARM_NUM_TARGETS];
+
+void kvm_register_target_sys_reg_table(unsigned int target,
+				       struct kvm_sys_reg_target_table *table)
+{
+	target_tables[target] = table;
+}
+
+/* Get specific register table for this target. */
+static const struct sys_reg_desc *get_target_table(unsigned target,
+						   bool mode_is_64,
+						   size_t *num)
+{
+	struct kvm_sys_reg_target_table *table;
+
+	table = target_tables[target];
+	if (mode_is_64) {
+		*num = table->table64.num;
+		return table->table64.table;
+	} else {
+		*num = table->table32.num;
+		return table->table32.table;
+	}
+}
+
+#define reg_to_match_value(x)						\
+	({								\
+		unsigned long val;					\
+		val  = (x)->Op0 << 14;					\
+		val |= (x)->Op1 << 11;					\
+		val |= (x)->CRn << 7;					\
+		val |= (x)->CRm << 3;					\
+		val |= (x)->Op2;					\
+		val;							\
+	 })
+
+static int match_sys_reg(const void *key, const void *elt)
+{
+	const unsigned long pval = (unsigned long)key;
+	const struct sys_reg_desc *r = elt;
+
+	return pval - reg_to_match_value(r);
+}
+
+static const struct sys_reg_desc *find_reg(const struct sys_reg_params *params,
+					 const struct sys_reg_desc table[],
+					 unsigned int num)
+{
+	unsigned long pval = reg_to_match_value(params);
+
+	return bsearch((void *)pval, table, num, sizeof(table[0]), match_sys_reg);
+}
+
+int kvm_handle_cp14_load_store(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+	kvm_inject_undefined(vcpu);
+	return 1;
+}
+
+static void perform_access(struct kvm_vcpu *vcpu,
+			   struct sys_reg_params *params,
+			   const struct sys_reg_desc *r)
+{
+	/*
+	 * Not having an accessor means that we have configured a trap
+	 * that we don't know how to handle. This certainly qualifies
+	 * as a gross bug that should be fixed right away.
+	 */
+	BUG_ON(!r->access);
+
+	/* Skip instruction if instructed so */
+	if (likely(r->access(vcpu, params, r)))
+		kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
+}
+
+/*
+ * emulate_cp --  tries to match a sys_reg access in a handling table, and
+ *                call the corresponding trap handler.
+ *
+ * @params: pointer to the descriptor of the access
+ * @table: array of trap descriptors
+ * @num: size of the trap descriptor array
+ *
+ * Return 0 if the access has been handled, and -1 if not.
+ */
+static int emulate_cp(struct kvm_vcpu *vcpu,
+		      struct sys_reg_params *params,
+		      const struct sys_reg_desc *table,
+		      size_t num)
+{
+	const struct sys_reg_desc *r;
+
+	if (!table)
+		return -1;	/* Not handled */
+
+	r = find_reg(params, table, num);
+
+	if (r) {
+		perform_access(vcpu, params, r);
+		return 0;
+	}
+
+	/* Not handled */
+	return -1;
+}
+
+static void unhandled_cp_access(struct kvm_vcpu *vcpu,
+				struct sys_reg_params *params)
+{
+	u8 hsr_ec = kvm_vcpu_trap_get_class(vcpu);
+	int cp = -1;
+
+	switch(hsr_ec) {
+	case ESR_ELx_EC_CP15_32:
+	case ESR_ELx_EC_CP15_64:
+		cp = 15;
+		break;
+	case ESR_ELx_EC_CP14_MR:
+	case ESR_ELx_EC_CP14_64:
+		cp = 14;
+		break;
+	default:
+		WARN_ON(1);
+	}
+
+	kvm_err("Unsupported guest CP%d access at: %08lx\n",
+		cp, *vcpu_pc(vcpu));
+	print_sys_reg_instr(params);
+	kvm_inject_undefined(vcpu);
+}
+
+/**
+ * kvm_handle_cp_64 -- handles a mrrc/mcrr trap on a guest CP14/CP15 access
+ * @vcpu: The VCPU pointer
+ * @run:  The kvm_run struct
+ */
+static int kvm_handle_cp_64(struct kvm_vcpu *vcpu,
+			    const struct sys_reg_desc *global,
+			    size_t nr_global,
+			    const struct sys_reg_desc *target_specific,
+			    size_t nr_specific)
+{
+	struct sys_reg_params params;
+	u32 hsr = kvm_vcpu_get_hsr(vcpu);
+	int Rt = kvm_vcpu_sys_get_rt(vcpu);
+	int Rt2 = (hsr >> 10) & 0x1f;
+
+	params.is_aarch32 = true;
+	params.is_32bit = false;
+	params.CRm = (hsr >> 1) & 0xf;
+	params.is_write = ((hsr & 1) == 0);
+
+	params.Op0 = 0;
+	params.Op1 = (hsr >> 16) & 0xf;
+	params.Op2 = 0;
+	params.CRn = 0;
+
+	/*
+	 * Make a 64-bit value out of Rt and Rt2. As we use the same trap
+	 * backends between AArch32 and AArch64, we get away with it.
+	 */
+	if (params.is_write) {
+		params.regval = vcpu_get_reg(vcpu, Rt) & 0xffffffff;
+		params.regval |= vcpu_get_reg(vcpu, Rt2) << 32;
+	}
+
+	/*
+	 * Try to emulate the coprocessor access using the target
+	 * specific table first, and using the global table afterwards.
+	 * If either of the tables contains a handler, handle the
+	 * potential register operation in the case of a read and return
+	 * with success.
+	 */
+	if (!emulate_cp(vcpu, &params, target_specific, nr_specific) ||
+	    !emulate_cp(vcpu, &params, global, nr_global)) {
+		/* Split up the value between registers for the read side */
+		if (!params.is_write) {
+			vcpu_set_reg(vcpu, Rt, lower_32_bits(params.regval));
+			vcpu_set_reg(vcpu, Rt2, upper_32_bits(params.regval));
+		}
+
+		return 1;
+	}
+
+	unhandled_cp_access(vcpu, &params);
+	return 1;
+}
+
+/**
+ * kvm_handle_cp_32 -- handles a mrc/mcr trap on a guest CP14/CP15 access
+ * @vcpu: The VCPU pointer
+ * @run:  The kvm_run struct
+ */
+static int kvm_handle_cp_32(struct kvm_vcpu *vcpu,
+			    const struct sys_reg_desc *global,
+			    size_t nr_global,
+			    const struct sys_reg_desc *target_specific,
+			    size_t nr_specific)
+{
+	struct sys_reg_params params;
+	u32 hsr = kvm_vcpu_get_hsr(vcpu);
+	int Rt  = kvm_vcpu_sys_get_rt(vcpu);
+
+	params.is_aarch32 = true;
+	params.is_32bit = true;
+	params.CRm = (hsr >> 1) & 0xf;
+	params.regval = vcpu_get_reg(vcpu, Rt);
+	params.is_write = ((hsr & 1) == 0);
+	params.CRn = (hsr >> 10) & 0xf;
+	params.Op0 = 0;
+	params.Op1 = (hsr >> 14) & 0x7;
+	params.Op2 = (hsr >> 17) & 0x7;
+
+	if (!emulate_cp(vcpu, &params, target_specific, nr_specific) ||
+	    !emulate_cp(vcpu, &params, global, nr_global)) {
+		if (!params.is_write)
+			vcpu_set_reg(vcpu, Rt, params.regval);
+		return 1;
+	}
+
+	unhandled_cp_access(vcpu, &params);
+	return 1;
+}
+
+int kvm_handle_cp15_64(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+	const struct sys_reg_desc *target_specific;
+	size_t num;
+
+	target_specific = get_target_table(vcpu->arch.target, false, &num);
+	return kvm_handle_cp_64(vcpu,
+				cp15_64_regs, ARRAY_SIZE(cp15_64_regs),
+				target_specific, num);
+}
+
+int kvm_handle_cp15_32(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+	const struct sys_reg_desc *target_specific;
+	size_t num;
+
+	target_specific = get_target_table(vcpu->arch.target, false, &num);
+	return kvm_handle_cp_32(vcpu,
+				cp15_regs, ARRAY_SIZE(cp15_regs),
+				target_specific, num);
+}
+
+int kvm_handle_cp14_64(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+	return kvm_handle_cp_64(vcpu,
+				cp14_64_regs, ARRAY_SIZE(cp14_64_regs),
+				NULL, 0);
+}
+
+int kvm_handle_cp14_32(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+	return kvm_handle_cp_32(vcpu,
+				cp14_regs, ARRAY_SIZE(cp14_regs),
+				NULL, 0);
+}
+
+static int emulate_sys_reg(struct kvm_vcpu *vcpu,
+			   struct sys_reg_params *params)
+{
+	size_t num;
+	const struct sys_reg_desc *table, *r;
+
+	table = get_target_table(vcpu->arch.target, true, &num);
+
+	/* Search target-specific then generic table. */
+	r = find_reg(params, table, num);
+	if (!r)
+		r = find_reg(params, sys_reg_descs, ARRAY_SIZE(sys_reg_descs));
+
+	if (likely(r)) {
+		perform_access(vcpu, params, r);
+	} else {
+		kvm_err("Unsupported guest sys_reg access at: %lx\n",
+			*vcpu_pc(vcpu));
+		print_sys_reg_instr(params);
+		kvm_inject_undefined(vcpu);
+	}
+	return 1;
+}
+
+static void reset_sys_reg_descs(struct kvm_vcpu *vcpu,
+				const struct sys_reg_desc *table, size_t num,
+				unsigned long *bmap)
+{
+	unsigned long i;
+
+	for (i = 0; i < num; i++)
+		if (table[i].reset) {
+			int reg = table[i].reg;
+
+			table[i].reset(vcpu, &table[i]);
+			if (reg > 0 && reg < NR_SYS_REGS)
+				set_bit(reg, bmap);
+		}
+}
+
+/**
+ * kvm_handle_sys_reg -- handles a mrs/msr trap on a guest sys_reg access
+ * @vcpu: The VCPU pointer
+ * @run:  The kvm_run struct
+ */
+int kvm_handle_sys_reg(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+	struct sys_reg_params params;
+	unsigned long esr = kvm_vcpu_get_hsr(vcpu);
+	int Rt = kvm_vcpu_sys_get_rt(vcpu);
+	int ret;
+
+	trace_kvm_handle_sys_reg(esr);
+
+	params.is_aarch32 = false;
+	params.is_32bit = false;
+	params.Op0 = (esr >> 20) & 3;
+	params.Op1 = (esr >> 14) & 0x7;
+	params.CRn = (esr >> 10) & 0xf;
+	params.CRm = (esr >> 1) & 0xf;
+	params.Op2 = (esr >> 17) & 0x7;
+	params.regval = vcpu_get_reg(vcpu, Rt);
+	params.is_write = !(esr & 1);
+
+	ret = emulate_sys_reg(vcpu, &params);
+
+	if (!params.is_write)
+		vcpu_set_reg(vcpu, Rt, params.regval);
+	return ret;
+}
+
+/******************************************************************************
+ * Userspace API
+ *****************************************************************************/
+
+static bool index_to_params(u64 id, struct sys_reg_params *params)
+{
+	switch (id & KVM_REG_SIZE_MASK) {
+	case KVM_REG_SIZE_U64:
+		/* Any unused index bits means it's not valid. */
+		if (id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK
+			      | KVM_REG_ARM_COPROC_MASK
+			      | KVM_REG_ARM64_SYSREG_OP0_MASK
+			      | KVM_REG_ARM64_SYSREG_OP1_MASK
+			      | KVM_REG_ARM64_SYSREG_CRN_MASK
+			      | KVM_REG_ARM64_SYSREG_CRM_MASK
+			      | KVM_REG_ARM64_SYSREG_OP2_MASK))
+			return false;
+		params->Op0 = ((id & KVM_REG_ARM64_SYSREG_OP0_MASK)
+			       >> KVM_REG_ARM64_SYSREG_OP0_SHIFT);
+		params->Op1 = ((id & KVM_REG_ARM64_SYSREG_OP1_MASK)
+			       >> KVM_REG_ARM64_SYSREG_OP1_SHIFT);
+		params->CRn = ((id & KVM_REG_ARM64_SYSREG_CRN_MASK)
+			       >> KVM_REG_ARM64_SYSREG_CRN_SHIFT);
+		params->CRm = ((id & KVM_REG_ARM64_SYSREG_CRM_MASK)
+			       >> KVM_REG_ARM64_SYSREG_CRM_SHIFT);
+		params->Op2 = ((id & KVM_REG_ARM64_SYSREG_OP2_MASK)
+			       >> KVM_REG_ARM64_SYSREG_OP2_SHIFT);
+		return true;
+	default:
+		return false;
+	}
+}
+
+const struct sys_reg_desc *find_reg_by_id(u64 id,
+					  struct sys_reg_params *params,
+					  const struct sys_reg_desc table[],
+					  unsigned int num)
+{
+	if (!index_to_params(id, params))
+		return NULL;
+
+	return find_reg(params, table, num);
+}
+
+/* Decode an index value, and find the sys_reg_desc entry. */
+static const struct sys_reg_desc *index_to_sys_reg_desc(struct kvm_vcpu *vcpu,
+						    u64 id)
+{
+	size_t num;
+	const struct sys_reg_desc *table, *r;
+	struct sys_reg_params params;
+
+	/* We only do sys_reg for now. */
+	if ((id & KVM_REG_ARM_COPROC_MASK) != KVM_REG_ARM64_SYSREG)
+		return NULL;
+
+	if (!index_to_params(id, &params))
+		return NULL;
+
+	table = get_target_table(vcpu->arch.target, true, &num);
+	r = find_reg(&params, table, num);
+	if (!r)
+		r = find_reg(&params, sys_reg_descs, ARRAY_SIZE(sys_reg_descs));
+
+	/* Not saved in the sys_reg array and not otherwise accessible? */
+	if (r && !(r->reg || r->get_user))
+		r = NULL;
+
+	return r;
+}
+
+/*
+ * These are the invariant sys_reg registers: we let the guest see the
+ * host versions of these, so they're part of the guest state.
+ *
+ * A future CPU may provide a mechanism to present different values to
+ * the guest, or a future kvm may trap them.
+ */
+
+#define FUNCTION_INVARIANT(reg)						\
+	static void get_##reg(struct kvm_vcpu *v,			\
+			      const struct sys_reg_desc *r)		\
+	{								\
+		((struct sys_reg_desc *)r)->val = read_sysreg(reg);	\
+	}
+
+FUNCTION_INVARIANT(midr_el1)
+FUNCTION_INVARIANT(ctr_el0)
+FUNCTION_INVARIANT(revidr_el1)
+FUNCTION_INVARIANT(clidr_el1)
+FUNCTION_INVARIANT(aidr_el1)
+
+/* ->val is filled in by kvm_sys_reg_table_init() */
+static struct sys_reg_desc invariant_sys_regs[] = {
+	{ SYS_DESC(SYS_MIDR_EL1), NULL, get_midr_el1 },
+	{ SYS_DESC(SYS_REVIDR_EL1), NULL, get_revidr_el1 },
+	{ SYS_DESC(SYS_CLIDR_EL1), NULL, get_clidr_el1 },
+	{ SYS_DESC(SYS_AIDR_EL1), NULL, get_aidr_el1 },
+	{ SYS_DESC(SYS_CTR_EL0), NULL, get_ctr_el0 },
+};
+
+static int reg_from_user(u64 *val, const void __user *uaddr, u64 id)
+{
+	if (copy_from_user(val, uaddr, KVM_REG_SIZE(id)) != 0)
+		return -EFAULT;
+	return 0;
+}
+
+static int reg_to_user(void __user *uaddr, const u64 *val, u64 id)
+{
+	if (copy_to_user(uaddr, val, KVM_REG_SIZE(id)) != 0)
+		return -EFAULT;
+	return 0;
+}
+
+static int get_invariant_sys_reg(u64 id, void __user *uaddr)
+{
+	struct sys_reg_params params;
+	const struct sys_reg_desc *r;
+
+	r = find_reg_by_id(id, &params, invariant_sys_regs,
+			   ARRAY_SIZE(invariant_sys_regs));
+	if (!r)
+		return -ENOENT;
+
+	return reg_to_user(uaddr, &r->val, id);
+}
+
+static int set_invariant_sys_reg(u64 id, void __user *uaddr)
+{
+	struct sys_reg_params params;
+	const struct sys_reg_desc *r;
+	int err;
+	u64 val = 0; /* Make sure high bits are 0 for 32-bit regs */
+
+	r = find_reg_by_id(id, &params, invariant_sys_regs,
+			   ARRAY_SIZE(invariant_sys_regs));
+	if (!r)
+		return -ENOENT;
+
+	err = reg_from_user(&val, uaddr, id);
+	if (err)
+		return err;
+
+	/* This is what we mean by invariant: you can't change it. */
+	if (r->val != val)
+		return -EINVAL;
+
+	return 0;
+}
+
+static bool is_valid_cache(u32 val)
+{
+	u32 level, ctype;
+
+	if (val >= CSSELR_MAX)
+		return false;
+
+	/* Bottom bit is Instruction or Data bit.  Next 3 bits are level. */
+	level = (val >> 1);
+	ctype = (cache_levels >> (level * 3)) & 7;
+
+	switch (ctype) {
+	case 0: /* No cache */
+		return false;
+	case 1: /* Instruction cache only */
+		return (val & 1);
+	case 2: /* Data cache only */
+	case 4: /* Unified cache */
+		return !(val & 1);
+	case 3: /* Separate instruction and data caches */
+		return true;
+	default: /* Reserved: we can't know instruction or data. */
+		return false;
+	}
+}
+
+static int demux_c15_get(u64 id, void __user *uaddr)
+{
+	u32 val;
+	u32 __user *uval = uaddr;
+
+	/* Fail if we have unknown bits set. */
+	if (id & ~(KVM_REG_ARCH_MASK|KVM_REG_SIZE_MASK|KVM_REG_ARM_COPROC_MASK
+		   | ((1 << KVM_REG_ARM_COPROC_SHIFT)-1)))
+		return -ENOENT;
+
+	switch (id & KVM_REG_ARM_DEMUX_ID_MASK) {
+	case KVM_REG_ARM_DEMUX_ID_CCSIDR:
+		if (KVM_REG_SIZE(id) != 4)
+			return -ENOENT;
+		val = (id & KVM_REG_ARM_DEMUX_VAL_MASK)
+			>> KVM_REG_ARM_DEMUX_VAL_SHIFT;
+		if (!is_valid_cache(val))
+			return -ENOENT;
+
+		return put_user(get_ccsidr(val), uval);
+	default:
+		return -ENOENT;
+	}
+}
+
+static int demux_c15_set(u64 id, void __user *uaddr)
+{
+	u32 val, newval;
+	u32 __user *uval = uaddr;
+
+	/* Fail if we have unknown bits set. */
+	if (id & ~(KVM_REG_ARCH_MASK|KVM_REG_SIZE_MASK|KVM_REG_ARM_COPROC_MASK
+		   | ((1 << KVM_REG_ARM_COPROC_SHIFT)-1)))
+		return -ENOENT;
+
+	switch (id & KVM_REG_ARM_DEMUX_ID_MASK) {
+	case KVM_REG_ARM_DEMUX_ID_CCSIDR:
+		if (KVM_REG_SIZE(id) != 4)
+			return -ENOENT;
+		val = (id & KVM_REG_ARM_DEMUX_VAL_MASK)
+			>> KVM_REG_ARM_DEMUX_VAL_SHIFT;
+		if (!is_valid_cache(val))
+			return -ENOENT;
+
+		if (get_user(newval, uval))
+			return -EFAULT;
+
+		/* This is also invariant: you can't change it. */
+		if (newval != get_ccsidr(val))
+			return -EINVAL;
+		return 0;
+	default:
+		return -ENOENT;
+	}
+}
+
+int kvm_arm_sys_reg_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
+{
+	const struct sys_reg_desc *r;
+	void __user *uaddr = (void __user *)(unsigned long)reg->addr;
+
+	if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_DEMUX)
+		return demux_c15_get(reg->id, uaddr);
+
+	if (KVM_REG_SIZE(reg->id) != sizeof(__u64))
+		return -ENOENT;
+
+	r = index_to_sys_reg_desc(vcpu, reg->id);
+	if (!r)
+		return get_invariant_sys_reg(reg->id, uaddr);
+
+	if (r->get_user)
+		return (r->get_user)(vcpu, r, reg, uaddr);
+
+	return reg_to_user(uaddr, &__vcpu_sys_reg(vcpu, r->reg), reg->id);
+}
+
+int kvm_arm_sys_reg_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
+{
+	const struct sys_reg_desc *r;
+	void __user *uaddr = (void __user *)(unsigned long)reg->addr;
+
+	if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_DEMUX)
+		return demux_c15_set(reg->id, uaddr);
+
+	if (KVM_REG_SIZE(reg->id) != sizeof(__u64))
+		return -ENOENT;
+
+	r = index_to_sys_reg_desc(vcpu, reg->id);
+	if (!r)
+		return set_invariant_sys_reg(reg->id, uaddr);
+
+	if (r->set_user)
+		return (r->set_user)(vcpu, r, reg, uaddr);
+
+	return reg_from_user(&__vcpu_sys_reg(vcpu, r->reg), uaddr, reg->id);
+}
+
+static unsigned int num_demux_regs(void)
+{
+	unsigned int i, count = 0;
+
+	for (i = 0; i < CSSELR_MAX; i++)
+		if (is_valid_cache(i))
+			count++;
+
+	return count;
+}
+
+static int write_demux_regids(u64 __user *uindices)
+{
+	u64 val = KVM_REG_ARM64 | KVM_REG_SIZE_U32 | KVM_REG_ARM_DEMUX;
+	unsigned int i;
+
+	val |= KVM_REG_ARM_DEMUX_ID_CCSIDR;
+	for (i = 0; i < CSSELR_MAX; i++) {
+		if (!is_valid_cache(i))
+			continue;
+		if (put_user(val | i, uindices))
+			return -EFAULT;
+		uindices++;
+	}
+	return 0;
+}
+
+static u64 sys_reg_to_index(const struct sys_reg_desc *reg)
+{
+	return (KVM_REG_ARM64 | KVM_REG_SIZE_U64 |
+		KVM_REG_ARM64_SYSREG |
+		(reg->Op0 << KVM_REG_ARM64_SYSREG_OP0_SHIFT) |
+		(reg->Op1 << KVM_REG_ARM64_SYSREG_OP1_SHIFT) |
+		(reg->CRn << KVM_REG_ARM64_SYSREG_CRN_SHIFT) |
+		(reg->CRm << KVM_REG_ARM64_SYSREG_CRM_SHIFT) |
+		(reg->Op2 << KVM_REG_ARM64_SYSREG_OP2_SHIFT));
+}
+
+static bool copy_reg_to_user(const struct sys_reg_desc *reg, u64 __user **uind)
+{
+	if (!*uind)
+		return true;
+
+	if (put_user(sys_reg_to_index(reg), *uind))
+		return false;
+
+	(*uind)++;
+	return true;
+}
+
+static int walk_one_sys_reg(const struct sys_reg_desc *rd,
+			    u64 __user **uind,
+			    unsigned int *total)
+{
+	/*
+	 * Ignore registers we trap but don't save,
+	 * and for which no custom user accessor is provided.
+	 */
+	if (!(rd->reg || rd->get_user))
+		return 0;
+
+	if (!copy_reg_to_user(rd, uind))
+		return -EFAULT;
+
+	(*total)++;
+	return 0;
+}
+
+/* Assumed ordered tables, see kvm_sys_reg_table_init. */
+static int walk_sys_regs(struct kvm_vcpu *vcpu, u64 __user *uind)
+{
+	const struct sys_reg_desc *i1, *i2, *end1, *end2;
+	unsigned int total = 0;
+	size_t num;
+	int err;
+
+	/* We check for duplicates here, to allow arch-specific overrides. */
+	i1 = get_target_table(vcpu->arch.target, true, &num);
+	end1 = i1 + num;
+	i2 = sys_reg_descs;
+	end2 = sys_reg_descs + ARRAY_SIZE(sys_reg_descs);
+
+	BUG_ON(i1 == end1 || i2 == end2);
+
+	/* Walk carefully, as both tables may refer to the same register. */
+	while (i1 || i2) {
+		int cmp = cmp_sys_reg(i1, i2);
+		/* target-specific overrides generic entry. */
+		if (cmp <= 0)
+			err = walk_one_sys_reg(i1, &uind, &total);
+		else
+			err = walk_one_sys_reg(i2, &uind, &total);
+
+		if (err)
+			return err;
+
+		if (cmp <= 0 && ++i1 == end1)
+			i1 = NULL;
+		if (cmp >= 0 && ++i2 == end2)
+			i2 = NULL;
+	}
+	return total;
+}
+
+unsigned long kvm_arm_num_sys_reg_descs(struct kvm_vcpu *vcpu)
+{
+	return ARRAY_SIZE(invariant_sys_regs)
+		+ num_demux_regs()
+		+ walk_sys_regs(vcpu, (u64 __user *)NULL);
+}
+
+int kvm_arm_copy_sys_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
+{
+	unsigned int i;
+	int err;
+
+	/* Then give them all the invariant registers' indices. */
+	for (i = 0; i < ARRAY_SIZE(invariant_sys_regs); i++) {
+		if (put_user(sys_reg_to_index(&invariant_sys_regs[i]), uindices))
+			return -EFAULT;
+		uindices++;
+	}
+
+	err = walk_sys_regs(vcpu, uindices);
+	if (err < 0)
+		return err;
+	uindices += err;
+
+	return write_demux_regids(uindices);
+}
+
+static int check_sysreg_table(const struct sys_reg_desc *table, unsigned int n)
+{
+	unsigned int i;
+
+	for (i = 1; i < n; i++) {
+		if (cmp_sys_reg(&table[i-1], &table[i]) >= 0) {
+			kvm_err("sys_reg table %p out of order (%d)\n", table, i - 1);
+			return 1;
+		}
+	}
+
+	return 0;
+}
+
+void kvm_sys_reg_table_init(void)
+{
+	unsigned int i;
+	struct sys_reg_desc clidr;
+
+	/* Make sure tables are unique and in order. */
+	BUG_ON(check_sysreg_table(sys_reg_descs, ARRAY_SIZE(sys_reg_descs)));
+	BUG_ON(check_sysreg_table(cp14_regs, ARRAY_SIZE(cp14_regs)));
+	BUG_ON(check_sysreg_table(cp14_64_regs, ARRAY_SIZE(cp14_64_regs)));
+	BUG_ON(check_sysreg_table(cp15_regs, ARRAY_SIZE(cp15_regs)));
+	BUG_ON(check_sysreg_table(cp15_64_regs, ARRAY_SIZE(cp15_64_regs)));
+	BUG_ON(check_sysreg_table(invariant_sys_regs, ARRAY_SIZE(invariant_sys_regs)));
+
+	/* We abuse the reset function to overwrite the table itself. */
+	for (i = 0; i < ARRAY_SIZE(invariant_sys_regs); i++)
+		invariant_sys_regs[i].reset(NULL, &invariant_sys_regs[i]);
+
+	/*
+	 * CLIDR format is awkward, so clean it up.  See ARM B4.1.20:
+	 *
+	 *   If software reads the Cache Type fields from Ctype1
+	 *   upwards, once it has seen a value of 0b000, no caches
+	 *   exist at further-out levels of the hierarchy. So, for
+	 *   example, if Ctype3 is the first Cache Type field with a
+	 *   value of 0b000, the values of Ctype4 to Ctype7 must be
+	 *   ignored.
+	 */
+	get_clidr_el1(NULL, &clidr); /* Ugly... */
+	cache_levels = clidr.val;
+	for (i = 0; i < 7; i++)
+		if (((cache_levels >> (i*3)) & 7) == 0)
+			break;
+	/* Clear all higher bits. */
+	cache_levels &= (1 << (i*3))-1;
+}
+
+/**
+ * kvm_reset_sys_regs - sets system registers to reset value
+ * @vcpu: The VCPU pointer
+ *
+ * This function finds the right table above and sets the registers on the
+ * virtual CPU struct to their architecturally defined reset values.
+ */
+void kvm_reset_sys_regs(struct kvm_vcpu *vcpu)
+{
+	size_t num;
+	const struct sys_reg_desc *table;
+	DECLARE_BITMAP(bmap, NR_SYS_REGS) = { 0, };
+
+	/* Generic chip reset first (so target could override). */
+	reset_sys_reg_descs(vcpu, sys_reg_descs, ARRAY_SIZE(sys_reg_descs), bmap);
+
+	table = get_target_table(vcpu->arch.target, true, &num);
+	reset_sys_reg_descs(vcpu, table, num, bmap);
+
+	for (num = 1; num < NR_SYS_REGS; num++) {
+		if (WARN(!test_bit(num, bmap),
+			 "Didn't reset __vcpu_sys_reg(%zi)\n", num))
+			break;
+	}
+}