| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Copyright (C) 2021 Google LLC |
| * Author: Fuad Tabba <tabba@google.com> |
| */ |
| |
| #include <linux/irqchip/arm-gic-v3.h> |
| |
| #include <asm/kvm_asm.h> |
| #include <asm/kvm_mmu.h> |
| |
| #include <hyp/adjust_pc.h> |
| |
| #include <nvhe/fixed_config.h> |
| |
| #include "../../sys_regs.h" |
| |
| /* |
| * Copies of the host's CPU features registers holding sanitized values at hyp. |
| */ |
| u64 id_aa64pfr0_el1_sys_val; |
| u64 id_aa64pfr1_el1_sys_val; |
| u64 id_aa64isar0_el1_sys_val; |
| u64 id_aa64isar1_el1_sys_val; |
| u64 id_aa64isar2_el1_sys_val; |
| u64 id_aa64mmfr0_el1_sys_val; |
| u64 id_aa64mmfr1_el1_sys_val; |
| u64 id_aa64mmfr2_el1_sys_val; |
| u64 id_aa64smfr0_el1_sys_val; |
| |
| /* |
| * Inject an unknown/undefined exception to an AArch64 guest while most of its |
| * sysregs are live. |
| */ |
| static void inject_undef64(struct kvm_vcpu *vcpu) |
| { |
| u64 esr = (ESR_ELx_EC_UNKNOWN << ESR_ELx_EC_SHIFT); |
| |
| *vcpu_pc(vcpu) = read_sysreg_el2(SYS_ELR); |
| *vcpu_cpsr(vcpu) = read_sysreg_el2(SYS_SPSR); |
| |
| kvm_pend_exception(vcpu, EXCEPT_AA64_EL1_SYNC); |
| |
| __kvm_adjust_pc(vcpu); |
| |
| write_sysreg_el1(esr, SYS_ESR); |
| write_sysreg_el1(read_sysreg_el2(SYS_ELR), SYS_ELR); |
| write_sysreg_el2(*vcpu_pc(vcpu), SYS_ELR); |
| write_sysreg_el2(*vcpu_cpsr(vcpu), SYS_SPSR); |
| } |
| |
| /* |
| * Returns the restricted features values of the feature register based on the |
| * limitations in restrict_fields. |
| * A feature id field value of 0b0000 does not impose any restrictions. |
| * Note: Use only for unsigned feature field values. |
| */ |
| static u64 get_restricted_features_unsigned(u64 sys_reg_val, |
| u64 restrict_fields) |
| { |
| u64 value = 0UL; |
| u64 mask = GENMASK_ULL(ARM64_FEATURE_FIELD_BITS - 1, 0); |
| |
| /* |
| * According to the Arm Architecture Reference Manual, feature fields |
| * use increasing values to indicate increases in functionality. |
| * Iterate over the restricted feature fields and calculate the minimum |
| * unsigned value between the one supported by the system, and what the |
| * value is being restricted to. |
| */ |
| while (sys_reg_val && restrict_fields) { |
| value |= min(sys_reg_val & mask, restrict_fields & mask); |
| sys_reg_val &= ~mask; |
| restrict_fields &= ~mask; |
| mask <<= ARM64_FEATURE_FIELD_BITS; |
| } |
| |
| return value; |
| } |
| |
| /* |
| * Functions that return the value of feature id registers for protected VMs |
| * based on allowed features, system features, and KVM support. |
| */ |
| |
| static u64 get_pvm_id_aa64pfr0(const struct kvm_vcpu *vcpu) |
| { |
| u64 set_mask = 0; |
| u64 allow_mask = PVM_ID_AA64PFR0_ALLOW; |
| |
| set_mask |= get_restricted_features_unsigned(id_aa64pfr0_el1_sys_val, |
| PVM_ID_AA64PFR0_RESTRICT_UNSIGNED); |
| |
| return (id_aa64pfr0_el1_sys_val & allow_mask) | set_mask; |
| } |
| |
| static u64 get_pvm_id_aa64pfr1(const struct kvm_vcpu *vcpu) |
| { |
| const struct kvm *kvm = (const struct kvm *)kern_hyp_va(vcpu->kvm); |
| u64 allow_mask = PVM_ID_AA64PFR1_ALLOW; |
| |
| if (!kvm_has_mte(kvm)) |
| allow_mask &= ~ARM64_FEATURE_MASK(ID_AA64PFR1_EL1_MTE); |
| |
| return id_aa64pfr1_el1_sys_val & allow_mask; |
| } |
| |
| static u64 get_pvm_id_aa64zfr0(const struct kvm_vcpu *vcpu) |
| { |
| /* |
| * No support for Scalable Vectors, therefore, hyp has no sanitized |
| * copy of the feature id register. |
| */ |
| BUILD_BUG_ON(PVM_ID_AA64ZFR0_ALLOW != 0ULL); |
| return 0; |
| } |
| |
| static u64 get_pvm_id_aa64dfr0(const struct kvm_vcpu *vcpu) |
| { |
| /* |
| * No support for debug, including breakpoints, and watchpoints, |
| * therefore, pKVM has no sanitized copy of the feature id register. |
| */ |
| BUILD_BUG_ON(PVM_ID_AA64DFR0_ALLOW != 0ULL); |
| return 0; |
| } |
| |
| static u64 get_pvm_id_aa64dfr1(const struct kvm_vcpu *vcpu) |
| { |
| /* |
| * No support for debug, therefore, hyp has no sanitized copy of the |
| * feature id register. |
| */ |
| BUILD_BUG_ON(PVM_ID_AA64DFR1_ALLOW != 0ULL); |
| return 0; |
| } |
| |
| static u64 get_pvm_id_aa64afr0(const struct kvm_vcpu *vcpu) |
| { |
| /* |
| * No support for implementation defined features, therefore, hyp has no |
| * sanitized copy of the feature id register. |
| */ |
| BUILD_BUG_ON(PVM_ID_AA64AFR0_ALLOW != 0ULL); |
| return 0; |
| } |
| |
| static u64 get_pvm_id_aa64afr1(const struct kvm_vcpu *vcpu) |
| { |
| /* |
| * No support for implementation defined features, therefore, hyp has no |
| * sanitized copy of the feature id register. |
| */ |
| BUILD_BUG_ON(PVM_ID_AA64AFR1_ALLOW != 0ULL); |
| return 0; |
| } |
| |
| static u64 get_pvm_id_aa64isar0(const struct kvm_vcpu *vcpu) |
| { |
| return id_aa64isar0_el1_sys_val & PVM_ID_AA64ISAR0_ALLOW; |
| } |
| |
| static u64 get_pvm_id_aa64isar1(const struct kvm_vcpu *vcpu) |
| { |
| u64 allow_mask = PVM_ID_AA64ISAR1_ALLOW; |
| |
| if (!vcpu_has_ptrauth(vcpu)) |
| allow_mask &= ~(ARM64_FEATURE_MASK(ID_AA64ISAR1_EL1_APA) | |
| ARM64_FEATURE_MASK(ID_AA64ISAR1_EL1_API) | |
| ARM64_FEATURE_MASK(ID_AA64ISAR1_EL1_GPA) | |
| ARM64_FEATURE_MASK(ID_AA64ISAR1_EL1_GPI)); |
| |
| return id_aa64isar1_el1_sys_val & allow_mask; |
| } |
| |
| static u64 get_pvm_id_aa64isar2(const struct kvm_vcpu *vcpu) |
| { |
| u64 allow_mask = PVM_ID_AA64ISAR2_ALLOW; |
| |
| if (!vcpu_has_ptrauth(vcpu)) |
| allow_mask &= ~(ARM64_FEATURE_MASK(ID_AA64ISAR2_EL1_APA3) | |
| ARM64_FEATURE_MASK(ID_AA64ISAR2_EL1_GPA3)); |
| |
| return id_aa64isar2_el1_sys_val & allow_mask; |
| } |
| |
| static u64 get_pvm_id_aa64mmfr0(const struct kvm_vcpu *vcpu) |
| { |
| u64 set_mask; |
| |
| set_mask = get_restricted_features_unsigned(id_aa64mmfr0_el1_sys_val, |
| PVM_ID_AA64MMFR0_RESTRICT_UNSIGNED); |
| |
| return (id_aa64mmfr0_el1_sys_val & PVM_ID_AA64MMFR0_ALLOW) | set_mask; |
| } |
| |
| static u64 get_pvm_id_aa64mmfr1(const struct kvm_vcpu *vcpu) |
| { |
| return id_aa64mmfr1_el1_sys_val & PVM_ID_AA64MMFR1_ALLOW; |
| } |
| |
| static u64 get_pvm_id_aa64mmfr2(const struct kvm_vcpu *vcpu) |
| { |
| return id_aa64mmfr2_el1_sys_val & PVM_ID_AA64MMFR2_ALLOW; |
| } |
| |
| /* Read a sanitized cpufeature ID register by its encoding */ |
| u64 pvm_read_id_reg(const struct kvm_vcpu *vcpu, u32 id) |
| { |
| switch (id) { |
| case SYS_ID_AA64PFR0_EL1: |
| return get_pvm_id_aa64pfr0(vcpu); |
| case SYS_ID_AA64PFR1_EL1: |
| return get_pvm_id_aa64pfr1(vcpu); |
| case SYS_ID_AA64ZFR0_EL1: |
| return get_pvm_id_aa64zfr0(vcpu); |
| case SYS_ID_AA64DFR0_EL1: |
| return get_pvm_id_aa64dfr0(vcpu); |
| case SYS_ID_AA64DFR1_EL1: |
| return get_pvm_id_aa64dfr1(vcpu); |
| case SYS_ID_AA64AFR0_EL1: |
| return get_pvm_id_aa64afr0(vcpu); |
| case SYS_ID_AA64AFR1_EL1: |
| return get_pvm_id_aa64afr1(vcpu); |
| case SYS_ID_AA64ISAR0_EL1: |
| return get_pvm_id_aa64isar0(vcpu); |
| case SYS_ID_AA64ISAR1_EL1: |
| return get_pvm_id_aa64isar1(vcpu); |
| case SYS_ID_AA64ISAR2_EL1: |
| return get_pvm_id_aa64isar2(vcpu); |
| case SYS_ID_AA64MMFR0_EL1: |
| return get_pvm_id_aa64mmfr0(vcpu); |
| case SYS_ID_AA64MMFR1_EL1: |
| return get_pvm_id_aa64mmfr1(vcpu); |
| case SYS_ID_AA64MMFR2_EL1: |
| return get_pvm_id_aa64mmfr2(vcpu); |
| default: |
| /* Unhandled ID register, RAZ */ |
| return 0; |
| } |
| } |
| |
| static u64 read_id_reg(const struct kvm_vcpu *vcpu, |
| struct sys_reg_desc const *r) |
| { |
| return pvm_read_id_reg(vcpu, reg_to_encoding(r)); |
| } |
| |
| /* Handler to RAZ/WI sysregs */ |
| static bool pvm_access_raz_wi(struct kvm_vcpu *vcpu, struct sys_reg_params *p, |
| const struct sys_reg_desc *r) |
| { |
| if (!p->is_write) |
| p->regval = 0; |
| |
| return true; |
| } |
| |
| /* |
| * Accessor for AArch32 feature id registers. |
| * |
| * The value of these registers is "unknown" according to the spec if AArch32 |
| * isn't supported. |
| */ |
| static bool pvm_access_id_aarch32(struct kvm_vcpu *vcpu, |
| struct sys_reg_params *p, |
| const struct sys_reg_desc *r) |
| { |
| if (p->is_write) { |
| inject_undef64(vcpu); |
| return false; |
| } |
| |
| /* |
| * No support for AArch32 guests, therefore, pKVM has no sanitized copy |
| * of AArch32 feature id registers. |
| */ |
| BUILD_BUG_ON(FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_EL1), |
| PVM_ID_AA64PFR0_RESTRICT_UNSIGNED) > ID_AA64PFR0_EL1_EL1_IMP); |
| |
| return pvm_access_raz_wi(vcpu, p, r); |
| } |
| |
| /* |
| * Accessor for AArch64 feature id registers. |
| * |
| * If access is allowed, set the regval to the protected VM's view of the |
| * register and return true. |
| * Otherwise, inject an undefined exception and return false. |
| */ |
| static bool pvm_access_id_aarch64(struct kvm_vcpu *vcpu, |
| struct sys_reg_params *p, |
| const struct sys_reg_desc *r) |
| { |
| if (p->is_write) { |
| inject_undef64(vcpu); |
| return false; |
| } |
| |
| p->regval = read_id_reg(vcpu, r); |
| return true; |
| } |
| |
| static bool pvm_gic_read_sre(struct kvm_vcpu *vcpu, |
| struct sys_reg_params *p, |
| const struct sys_reg_desc *r) |
| { |
| /* pVMs only support GICv3. 'nuf said. */ |
| if (!p->is_write) |
| p->regval = ICC_SRE_EL1_DIB | ICC_SRE_EL1_DFB | ICC_SRE_EL1_SRE; |
| |
| return true; |
| } |
| |
| /* Mark the specified system register as an AArch32 feature id register. */ |
| #define AARCH32(REG) { SYS_DESC(REG), .access = pvm_access_id_aarch32 } |
| |
| /* Mark the specified system register as an AArch64 feature id register. */ |
| #define AARCH64(REG) { SYS_DESC(REG), .access = pvm_access_id_aarch64 } |
| |
| /* |
| * 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 = pvm_access_id_aarch64, \ |
| } |
| |
| /* Mark the specified system register as Read-As-Zero/Write-Ignored */ |
| #define RAZ_WI(REG) { SYS_DESC(REG), .access = pvm_access_raz_wi } |
| |
| /* Mark the specified system register as not being handled in hyp. */ |
| #define HOST_HANDLED(REG) { SYS_DESC(REG), .access = NULL } |
| |
| /* |
| * Architected system registers. |
| * Important: Must be sorted ascending by Op0, Op1, CRn, CRm, Op2 |
| * |
| * NOTE: Anything not explicitly listed here is *restricted by default*, i.e., |
| * it will lead to injecting an exception into the guest. |
| */ |
| static const struct sys_reg_desc pvm_sys_reg_descs[] = { |
| /* Cache maintenance by set/way operations are restricted. */ |
| |
| /* Debug and Trace Registers are restricted. */ |
| |
| /* AArch64 mappings of the AArch32 ID registers */ |
| /* CRm=1 */ |
| AARCH32(SYS_ID_PFR0_EL1), |
| AARCH32(SYS_ID_PFR1_EL1), |
| AARCH32(SYS_ID_DFR0_EL1), |
| AARCH32(SYS_ID_AFR0_EL1), |
| AARCH32(SYS_ID_MMFR0_EL1), |
| AARCH32(SYS_ID_MMFR1_EL1), |
| AARCH32(SYS_ID_MMFR2_EL1), |
| AARCH32(SYS_ID_MMFR3_EL1), |
| |
| /* CRm=2 */ |
| AARCH32(SYS_ID_ISAR0_EL1), |
| AARCH32(SYS_ID_ISAR1_EL1), |
| AARCH32(SYS_ID_ISAR2_EL1), |
| AARCH32(SYS_ID_ISAR3_EL1), |
| AARCH32(SYS_ID_ISAR4_EL1), |
| AARCH32(SYS_ID_ISAR5_EL1), |
| AARCH32(SYS_ID_MMFR4_EL1), |
| AARCH32(SYS_ID_ISAR6_EL1), |
| |
| /* CRm=3 */ |
| AARCH32(SYS_MVFR0_EL1), |
| AARCH32(SYS_MVFR1_EL1), |
| AARCH32(SYS_MVFR2_EL1), |
| ID_UNALLOCATED(3,3), |
| AARCH32(SYS_ID_PFR2_EL1), |
| AARCH32(SYS_ID_DFR1_EL1), |
| AARCH32(SYS_ID_MMFR5_EL1), |
| ID_UNALLOCATED(3,7), |
| |
| /* AArch64 ID registers */ |
| /* CRm=4 */ |
| AARCH64(SYS_ID_AA64PFR0_EL1), |
| AARCH64(SYS_ID_AA64PFR1_EL1), |
| ID_UNALLOCATED(4,2), |
| ID_UNALLOCATED(4,3), |
| AARCH64(SYS_ID_AA64ZFR0_EL1), |
| ID_UNALLOCATED(4,5), |
| ID_UNALLOCATED(4,6), |
| ID_UNALLOCATED(4,7), |
| AARCH64(SYS_ID_AA64DFR0_EL1), |
| AARCH64(SYS_ID_AA64DFR1_EL1), |
| ID_UNALLOCATED(5,2), |
| ID_UNALLOCATED(5,3), |
| AARCH64(SYS_ID_AA64AFR0_EL1), |
| AARCH64(SYS_ID_AA64AFR1_EL1), |
| ID_UNALLOCATED(5,6), |
| ID_UNALLOCATED(5,7), |
| AARCH64(SYS_ID_AA64ISAR0_EL1), |
| AARCH64(SYS_ID_AA64ISAR1_EL1), |
| AARCH64(SYS_ID_AA64ISAR2_EL1), |
| ID_UNALLOCATED(6,3), |
| ID_UNALLOCATED(6,4), |
| ID_UNALLOCATED(6,5), |
| ID_UNALLOCATED(6,6), |
| ID_UNALLOCATED(6,7), |
| AARCH64(SYS_ID_AA64MMFR0_EL1), |
| AARCH64(SYS_ID_AA64MMFR1_EL1), |
| AARCH64(SYS_ID_AA64MMFR2_EL1), |
| ID_UNALLOCATED(7,3), |
| ID_UNALLOCATED(7,4), |
| ID_UNALLOCATED(7,5), |
| ID_UNALLOCATED(7,6), |
| ID_UNALLOCATED(7,7), |
| |
| /* Scalable Vector Registers are restricted. */ |
| |
| RAZ_WI(SYS_ERRIDR_EL1), |
| RAZ_WI(SYS_ERRSELR_EL1), |
| RAZ_WI(SYS_ERXFR_EL1), |
| RAZ_WI(SYS_ERXCTLR_EL1), |
| RAZ_WI(SYS_ERXSTATUS_EL1), |
| RAZ_WI(SYS_ERXADDR_EL1), |
| RAZ_WI(SYS_ERXMISC0_EL1), |
| RAZ_WI(SYS_ERXMISC1_EL1), |
| |
| /* Performance Monitoring Registers are restricted. */ |
| |
| /* Limited Ordering Regions Registers are restricted. */ |
| |
| HOST_HANDLED(SYS_ICC_SGI1R_EL1), |
| HOST_HANDLED(SYS_ICC_ASGI1R_EL1), |
| HOST_HANDLED(SYS_ICC_SGI0R_EL1), |
| { SYS_DESC(SYS_ICC_SRE_EL1), .access = pvm_gic_read_sre, }, |
| |
| HOST_HANDLED(SYS_CCSIDR_EL1), |
| HOST_HANDLED(SYS_CLIDR_EL1), |
| HOST_HANDLED(SYS_CSSELR_EL1), |
| HOST_HANDLED(SYS_CTR_EL0), |
| |
| /* Performance Monitoring Registers are restricted. */ |
| |
| /* Activity Monitoring Registers are restricted. */ |
| |
| HOST_HANDLED(SYS_CNTP_TVAL_EL0), |
| HOST_HANDLED(SYS_CNTP_CTL_EL0), |
| HOST_HANDLED(SYS_CNTP_CVAL_EL0), |
| |
| /* Performance Monitoring Registers are restricted. */ |
| }; |
| |
| /* |
| * Checks that the sysreg table is unique and in-order. |
| * |
| * Returns 0 if the table is consistent, or 1 otherwise. |
| */ |
| int kvm_check_pvm_sysreg_table(void) |
| { |
| unsigned int i; |
| |
| for (i = 1; i < ARRAY_SIZE(pvm_sys_reg_descs); i++) { |
| if (cmp_sys_reg(&pvm_sys_reg_descs[i-1], &pvm_sys_reg_descs[i]) >= 0) |
| return 1; |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * Handler for protected VM MSR, MRS or System instruction execution. |
| * |
| * Returns true if the hypervisor has handled the exit, and control should go |
| * back to the guest, or false if it hasn't, to be handled by the host. |
| */ |
| bool kvm_handle_pvm_sysreg(struct kvm_vcpu *vcpu, u64 *exit_code) |
| { |
| const struct sys_reg_desc *r; |
| struct sys_reg_params params; |
| unsigned long esr = kvm_vcpu_get_esr(vcpu); |
| int Rt = kvm_vcpu_sys_get_rt(vcpu); |
| |
| params = esr_sys64_to_params(esr); |
| params.regval = vcpu_get_reg(vcpu, Rt); |
| |
| r = find_reg(¶ms, pvm_sys_reg_descs, ARRAY_SIZE(pvm_sys_reg_descs)); |
| |
| /* Undefined (RESTRICTED). */ |
| if (r == NULL) { |
| inject_undef64(vcpu); |
| return true; |
| } |
| |
| /* Handled by the host (HOST_HANDLED) */ |
| if (r->access == NULL) |
| return false; |
| |
| /* Handled by hyp: skip instruction if instructed to do so. */ |
| if (r->access(vcpu, ¶ms, r)) |
| __kvm_skip_instr(vcpu); |
| |
| if (!params.is_write) |
| vcpu_set_reg(vcpu, Rt, params.regval); |
| |
| return true; |
| } |
| |
| /* |
| * Handler for protected VM restricted exceptions. |
| * |
| * Inject an undefined exception into the guest and return true to indicate that |
| * the hypervisor has handled the exit, and control should go back to the guest. |
| */ |
| bool kvm_handle_pvm_restricted(struct kvm_vcpu *vcpu, u64 *exit_code) |
| { |
| inject_undef64(vcpu); |
| return true; |
| } |