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-rw-r--r--arch/arm64/kvm/inject_fault.c254
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diff --git a/arch/arm64/kvm/inject_fault.c b/arch/arm64/kvm/inject_fault.c
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+++ b/arch/arm64/kvm/inject_fault.c
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+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Fault injection for both 32 and 64bit guests.
+ *
+ * Copyright (C) 2012,2013 - ARM Ltd
+ * Author: Marc Zyngier <marc.zyngier@arm.com>
+ *
+ * Based on arch/arm/kvm/emulate.c
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Author: Christoffer Dall <c.dall@virtualopensystems.com>
+ */
+
+#include <linux/kvm_host.h>
+#include <asm/kvm_emulate.h>
+#include <asm/kvm_nested.h>
+#include <asm/esr.h>
+
+static void pend_sync_exception(struct kvm_vcpu *vcpu)
+{
+ /* If not nesting, EL1 is the only possible exception target */
+ if (likely(!vcpu_has_nv(vcpu))) {
+ kvm_pend_exception(vcpu, EXCEPT_AA64_EL1_SYNC);
+ return;
+ }
+
+ /*
+ * With NV, we need to pick between EL1 and EL2. Note that we
+ * never deal with a nesting exception here, hence never
+ * changing context, and the exception itself can be delayed
+ * until the next entry.
+ */
+ switch(*vcpu_cpsr(vcpu) & PSR_MODE_MASK) {
+ case PSR_MODE_EL2h:
+ case PSR_MODE_EL2t:
+ kvm_pend_exception(vcpu, EXCEPT_AA64_EL2_SYNC);
+ break;
+ case PSR_MODE_EL1h:
+ case PSR_MODE_EL1t:
+ kvm_pend_exception(vcpu, EXCEPT_AA64_EL1_SYNC);
+ break;
+ case PSR_MODE_EL0t:
+ if (vcpu_el2_tge_is_set(vcpu))
+ kvm_pend_exception(vcpu, EXCEPT_AA64_EL2_SYNC);
+ else
+ kvm_pend_exception(vcpu, EXCEPT_AA64_EL1_SYNC);
+ break;
+ default:
+ BUG();
+ }
+}
+
+static bool match_target_el(struct kvm_vcpu *vcpu, unsigned long target)
+{
+ return (vcpu_get_flag(vcpu, EXCEPT_MASK) == target);
+}
+
+static void inject_abt64(struct kvm_vcpu *vcpu, bool is_iabt, unsigned long addr)
+{
+ unsigned long cpsr = *vcpu_cpsr(vcpu);
+ bool is_aarch32 = vcpu_mode_is_32bit(vcpu);
+ u64 esr = 0;
+
+ pend_sync_exception(vcpu);
+
+ /*
+ * Build an {i,d}abort, depending on the level and the
+ * instruction set. Report an external synchronous abort.
+ */
+ if (kvm_vcpu_trap_il_is32bit(vcpu))
+ esr |= ESR_ELx_IL;
+
+ /*
+ * Here, the guest runs in AArch64 mode when in EL1. If we get
+ * an AArch32 fault, it means we managed to trap an EL0 fault.
+ */
+ if (is_aarch32 || (cpsr & PSR_MODE_MASK) == PSR_MODE_EL0t)
+ esr |= (ESR_ELx_EC_IABT_LOW << ESR_ELx_EC_SHIFT);
+ else
+ esr |= (ESR_ELx_EC_IABT_CUR << ESR_ELx_EC_SHIFT);
+
+ if (!is_iabt)
+ esr |= ESR_ELx_EC_DABT_LOW << ESR_ELx_EC_SHIFT;
+
+ esr |= ESR_ELx_FSC_EXTABT;
+
+ if (match_target_el(vcpu, unpack_vcpu_flag(EXCEPT_AA64_EL1_SYNC))) {
+ vcpu_write_sys_reg(vcpu, addr, FAR_EL1);
+ vcpu_write_sys_reg(vcpu, esr, ESR_EL1);
+ } else {
+ vcpu_write_sys_reg(vcpu, addr, FAR_EL2);
+ vcpu_write_sys_reg(vcpu, esr, ESR_EL2);
+ }
+}
+
+static void inject_undef64(struct kvm_vcpu *vcpu)
+{
+ u64 esr = (ESR_ELx_EC_UNKNOWN << ESR_ELx_EC_SHIFT);
+
+ pend_sync_exception(vcpu);
+
+ /*
+ * Build an unknown exception, depending on the instruction
+ * set.
+ */
+ if (kvm_vcpu_trap_il_is32bit(vcpu))
+ esr |= ESR_ELx_IL;
+
+ if (match_target_el(vcpu, unpack_vcpu_flag(EXCEPT_AA64_EL1_SYNC)))
+ vcpu_write_sys_reg(vcpu, esr, ESR_EL1);
+ else
+ vcpu_write_sys_reg(vcpu, esr, ESR_EL2);
+}
+
+#define DFSR_FSC_EXTABT_LPAE 0x10
+#define DFSR_FSC_EXTABT_nLPAE 0x08
+#define DFSR_LPAE BIT(9)
+#define TTBCR_EAE BIT(31)
+
+static void inject_undef32(struct kvm_vcpu *vcpu)
+{
+ kvm_pend_exception(vcpu, EXCEPT_AA32_UND);
+}
+
+/*
+ * Modelled after TakeDataAbortException() and TakePrefetchAbortException
+ * pseudocode.
+ */
+static void inject_abt32(struct kvm_vcpu *vcpu, bool is_pabt, u32 addr)
+{
+ u64 far;
+ u32 fsr;
+
+ /* Give the guest an IMPLEMENTATION DEFINED exception */
+ if (vcpu_read_sys_reg(vcpu, TCR_EL1) & TTBCR_EAE) {
+ fsr = DFSR_LPAE | DFSR_FSC_EXTABT_LPAE;
+ } else {
+ /* no need to shuffle FS[4] into DFSR[10] as its 0 */
+ fsr = DFSR_FSC_EXTABT_nLPAE;
+ }
+
+ far = vcpu_read_sys_reg(vcpu, FAR_EL1);
+
+ if (is_pabt) {
+ kvm_pend_exception(vcpu, EXCEPT_AA32_IABT);
+ far &= GENMASK(31, 0);
+ far |= (u64)addr << 32;
+ vcpu_write_sys_reg(vcpu, fsr, IFSR32_EL2);
+ } else { /* !iabt */
+ kvm_pend_exception(vcpu, EXCEPT_AA32_DABT);
+ far &= GENMASK(63, 32);
+ far |= addr;
+ vcpu_write_sys_reg(vcpu, fsr, ESR_EL1);
+ }
+
+ vcpu_write_sys_reg(vcpu, far, FAR_EL1);
+}
+
+/**
+ * kvm_inject_dabt - inject a data abort into the guest
+ * @vcpu: The VCPU to receive the data abort
+ * @addr: The address to report in the DFAR
+ *
+ * It is assumed that this code is called from the VCPU thread and that the
+ * VCPU therefore is not currently executing guest code.
+ */
+void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr)
+{
+ if (vcpu_el1_is_32bit(vcpu))
+ inject_abt32(vcpu, false, addr);
+ else
+ inject_abt64(vcpu, false, addr);
+}
+
+/**
+ * kvm_inject_pabt - inject a prefetch abort into the guest
+ * @vcpu: The VCPU to receive the prefetch abort
+ * @addr: The address to report in the DFAR
+ *
+ * It is assumed that this code is called from the VCPU thread and that the
+ * VCPU therefore is not currently executing guest code.
+ */
+void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr)
+{
+ if (vcpu_el1_is_32bit(vcpu))
+ inject_abt32(vcpu, true, addr);
+ else
+ inject_abt64(vcpu, true, addr);
+}
+
+void kvm_inject_size_fault(struct kvm_vcpu *vcpu)
+{
+ unsigned long addr, esr;
+
+ addr = kvm_vcpu_get_fault_ipa(vcpu);
+ addr |= kvm_vcpu_get_hfar(vcpu) & GENMASK(11, 0);
+
+ if (kvm_vcpu_trap_is_iabt(vcpu))
+ kvm_inject_pabt(vcpu, addr);
+ else
+ kvm_inject_dabt(vcpu, addr);
+
+ /*
+ * If AArch64 or LPAE, set FSC to 0 to indicate an Address
+ * Size Fault at level 0, as if exceeding PARange.
+ *
+ * Non-LPAE guests will only get the external abort, as there
+ * is no way to describe the ASF.
+ */
+ if (vcpu_el1_is_32bit(vcpu) &&
+ !(vcpu_read_sys_reg(vcpu, TCR_EL1) & TTBCR_EAE))
+ return;
+
+ esr = vcpu_read_sys_reg(vcpu, ESR_EL1);
+ esr &= ~GENMASK_ULL(5, 0);
+ vcpu_write_sys_reg(vcpu, esr, ESR_EL1);
+}
+
+/**
+ * kvm_inject_undefined - inject an undefined instruction into the guest
+ * @vcpu: The vCPU in which to inject the exception
+ *
+ * It is assumed that this code is called from the VCPU thread and that the
+ * VCPU therefore is not currently executing guest code.
+ */
+void kvm_inject_undefined(struct kvm_vcpu *vcpu)
+{
+ if (vcpu_el1_is_32bit(vcpu))
+ inject_undef32(vcpu);
+ else
+ inject_undef64(vcpu);
+}
+
+void kvm_set_sei_esr(struct kvm_vcpu *vcpu, u64 esr)
+{
+ vcpu_set_vsesr(vcpu, esr & ESR_ELx_ISS_MASK);
+ *vcpu_hcr(vcpu) |= HCR_VSE;
+}
+
+/**
+ * kvm_inject_vabt - inject an async abort / SError into the guest
+ * @vcpu: The VCPU to receive the exception
+ *
+ * It is assumed that this code is called from the VCPU thread and that the
+ * VCPU therefore is not currently executing guest code.
+ *
+ * Systems with the RAS Extensions specify an imp-def ESR (ISV/IDS = 1) with
+ * the remaining ISS all-zeros so that this error is not interpreted as an
+ * uncategorized RAS error. Without the RAS Extensions we can't specify an ESR
+ * value, so the CPU generates an imp-def value.
+ */
+void kvm_inject_vabt(struct kvm_vcpu *vcpu)
+{
+ kvm_set_sei_esr(vcpu, ESR_ELx_ISV);
+}