1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Fault injection for both 32 and 64bit guests. 4 * 5 * Copyright (C) 2012,2013 - ARM Ltd 6 * Author: Marc Zyngier <marc.zyngier@arm.com> 7 * 8 * Based on arch/arm/kvm/emulate.c 9 * Copyright (C) 2012 - Virtual Open Systems and Columbia University 10 * Author: Christoffer Dall <c.dall@virtualopensystems.com> 11 */ 12 13 #include <linux/kvm_host.h> 14 #include <asm/kvm_emulate.h> 15 #include <asm/esr.h> 16 17 static void inject_abt64(struct kvm_vcpu *vcpu, bool is_iabt, unsigned long addr) 18 { 19 unsigned long cpsr = *vcpu_cpsr(vcpu); 20 bool is_aarch32 = vcpu_mode_is_32bit(vcpu); 21 u32 esr = 0; 22 23 vcpu->arch.flags |= (KVM_ARM64_EXCEPT_AA64_EL1 | 24 KVM_ARM64_EXCEPT_AA64_ELx_SYNC | 25 KVM_ARM64_PENDING_EXCEPTION); 26 27 vcpu_write_sys_reg(vcpu, addr, FAR_EL1); 28 29 /* 30 * Build an {i,d}abort, depending on the level and the 31 * instruction set. Report an external synchronous abort. 32 */ 33 if (kvm_vcpu_trap_il_is32bit(vcpu)) 34 esr |= ESR_ELx_IL; 35 36 /* 37 * Here, the guest runs in AArch64 mode when in EL1. If we get 38 * an AArch32 fault, it means we managed to trap an EL0 fault. 39 */ 40 if (is_aarch32 || (cpsr & PSR_MODE_MASK) == PSR_MODE_EL0t) 41 esr |= (ESR_ELx_EC_IABT_LOW << ESR_ELx_EC_SHIFT); 42 else 43 esr |= (ESR_ELx_EC_IABT_CUR << ESR_ELx_EC_SHIFT); 44 45 if (!is_iabt) 46 esr |= ESR_ELx_EC_DABT_LOW << ESR_ELx_EC_SHIFT; 47 48 vcpu_write_sys_reg(vcpu, esr | ESR_ELx_FSC_EXTABT, ESR_EL1); 49 } 50 51 static void inject_undef64(struct kvm_vcpu *vcpu) 52 { 53 u32 esr = (ESR_ELx_EC_UNKNOWN << ESR_ELx_EC_SHIFT); 54 55 vcpu->arch.flags |= (KVM_ARM64_EXCEPT_AA64_EL1 | 56 KVM_ARM64_EXCEPT_AA64_ELx_SYNC | 57 KVM_ARM64_PENDING_EXCEPTION); 58 59 /* 60 * Build an unknown exception, depending on the instruction 61 * set. 62 */ 63 if (kvm_vcpu_trap_il_is32bit(vcpu)) 64 esr |= ESR_ELx_IL; 65 66 vcpu_write_sys_reg(vcpu, esr, ESR_EL1); 67 } 68 69 #define DFSR_FSC_EXTABT_LPAE 0x10 70 #define DFSR_FSC_EXTABT_nLPAE 0x08 71 #define DFSR_LPAE BIT(9) 72 #define TTBCR_EAE BIT(31) 73 74 static void inject_undef32(struct kvm_vcpu *vcpu) 75 { 76 vcpu->arch.flags |= (KVM_ARM64_EXCEPT_AA32_UND | 77 KVM_ARM64_PENDING_EXCEPTION); 78 } 79 80 /* 81 * Modelled after TakeDataAbortException() and TakePrefetchAbortException 82 * pseudocode. 83 */ 84 static void inject_abt32(struct kvm_vcpu *vcpu, bool is_pabt, u32 addr) 85 { 86 u64 far; 87 u32 fsr; 88 89 /* Give the guest an IMPLEMENTATION DEFINED exception */ 90 if (vcpu_read_sys_reg(vcpu, TCR_EL1) & TTBCR_EAE) { 91 fsr = DFSR_LPAE | DFSR_FSC_EXTABT_LPAE; 92 } else { 93 /* no need to shuffle FS[4] into DFSR[10] as its 0 */ 94 fsr = DFSR_FSC_EXTABT_nLPAE; 95 } 96 97 far = vcpu_read_sys_reg(vcpu, FAR_EL1); 98 99 if (is_pabt) { 100 vcpu->arch.flags |= (KVM_ARM64_EXCEPT_AA32_IABT | 101 KVM_ARM64_PENDING_EXCEPTION); 102 far &= GENMASK(31, 0); 103 far |= (u64)addr << 32; 104 vcpu_write_sys_reg(vcpu, fsr, IFSR32_EL2); 105 } else { /* !iabt */ 106 vcpu->arch.flags |= (KVM_ARM64_EXCEPT_AA32_DABT | 107 KVM_ARM64_PENDING_EXCEPTION); 108 far &= GENMASK(63, 32); 109 far |= addr; 110 vcpu_write_sys_reg(vcpu, fsr, ESR_EL1); 111 } 112 113 vcpu_write_sys_reg(vcpu, far, FAR_EL1); 114 } 115 116 /** 117 * kvm_inject_dabt - inject a data abort into the guest 118 * @vcpu: The VCPU to receive the data abort 119 * @addr: The address to report in the DFAR 120 * 121 * It is assumed that this code is called from the VCPU thread and that the 122 * VCPU therefore is not currently executing guest code. 123 */ 124 void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr) 125 { 126 if (vcpu_el1_is_32bit(vcpu)) 127 inject_abt32(vcpu, false, addr); 128 else 129 inject_abt64(vcpu, false, addr); 130 } 131 132 /** 133 * kvm_inject_pabt - inject a prefetch abort into the guest 134 * @vcpu: The VCPU to receive the prefetch abort 135 * @addr: The address to report in the DFAR 136 * 137 * It is assumed that this code is called from the VCPU thread and that the 138 * VCPU therefore is not currently executing guest code. 139 */ 140 void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr) 141 { 142 if (vcpu_el1_is_32bit(vcpu)) 143 inject_abt32(vcpu, true, addr); 144 else 145 inject_abt64(vcpu, true, addr); 146 } 147 148 void kvm_inject_size_fault(struct kvm_vcpu *vcpu) 149 { 150 unsigned long addr, esr; 151 152 addr = kvm_vcpu_get_fault_ipa(vcpu); 153 addr |= kvm_vcpu_get_hfar(vcpu) & GENMASK(11, 0); 154 155 if (kvm_vcpu_trap_is_iabt(vcpu)) 156 kvm_inject_pabt(vcpu, addr); 157 else 158 kvm_inject_dabt(vcpu, addr); 159 160 /* 161 * If AArch64 or LPAE, set FSC to 0 to indicate an Address 162 * Size Fault at level 0, as if exceeding PARange. 163 * 164 * Non-LPAE guests will only get the external abort, as there 165 * is no way to to describe the ASF. 166 */ 167 if (vcpu_el1_is_32bit(vcpu) && 168 !(vcpu_read_sys_reg(vcpu, TCR_EL1) & TTBCR_EAE)) 169 return; 170 171 esr = vcpu_read_sys_reg(vcpu, ESR_EL1); 172 esr &= ~GENMASK_ULL(5, 0); 173 vcpu_write_sys_reg(vcpu, esr, ESR_EL1); 174 } 175 176 /** 177 * kvm_inject_undefined - inject an undefined instruction into the guest 178 * @vcpu: The vCPU in which to inject the exception 179 * 180 * It is assumed that this code is called from the VCPU thread and that the 181 * VCPU therefore is not currently executing guest code. 182 */ 183 void kvm_inject_undefined(struct kvm_vcpu *vcpu) 184 { 185 if (vcpu_el1_is_32bit(vcpu)) 186 inject_undef32(vcpu); 187 else 188 inject_undef64(vcpu); 189 } 190 191 void kvm_set_sei_esr(struct kvm_vcpu *vcpu, u64 esr) 192 { 193 vcpu_set_vsesr(vcpu, esr & ESR_ELx_ISS_MASK); 194 *vcpu_hcr(vcpu) |= HCR_VSE; 195 } 196 197 /** 198 * kvm_inject_vabt - inject an async abort / SError into the guest 199 * @vcpu: The VCPU to receive the exception 200 * 201 * It is assumed that this code is called from the VCPU thread and that the 202 * VCPU therefore is not currently executing guest code. 203 * 204 * Systems with the RAS Extensions specify an imp-def ESR (ISV/IDS = 1) with 205 * the remaining ISS all-zeros so that this error is not interpreted as an 206 * uncategorized RAS error. Without the RAS Extensions we can't specify an ESR 207 * value, so the CPU generates an imp-def value. 208 */ 209 void kvm_inject_vabt(struct kvm_vcpu *vcpu) 210 { 211 kvm_set_sei_esr(vcpu, ESR_ELx_ISV); 212 } 213