diff options
| -rw-r--r-- | arch/arm64/include/asm/kvm_emulate.h | 14 | ||||
| -rw-r--r-- | arch/arm64/kvm/sys_regs.c | 23 |
2 files changed, 32 insertions, 5 deletions
diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h index fa8a08a1ccd5..64ce3fec73ee 100644 --- a/arch/arm64/include/asm/kvm_emulate.h +++ b/arch/arm64/include/asm/kvm_emulate.h @@ -220,6 +220,20 @@ static inline bool vcpu_el2_tge_is_set(const struct kvm_vcpu *vcpu) static inline bool vcpu_el2_amo_is_set(const struct kvm_vcpu *vcpu) { + /* + * DDI0487L.b Known Issue D22105 + * + * When executing at EL2 and HCR_EL2.{E2H,TGE} = {1, 0} it is + * IMPLEMENTATION DEFINED whether the effective value of HCR_EL2.AMO + * is the value programmed or 1. + * + * Make the implementation choice of treating the effective value as 1 as + * we cannot subsequently catch changes to TGE or AMO that would + * otherwise lead to the SError becoming deliverable. + */ + if (vcpu_is_el2(vcpu) && vcpu_el2_e2h_is_set(vcpu) && !vcpu_el2_tge_is_set(vcpu)) + return true; + return ctxt_sys_reg(&vcpu->arch.ctxt, HCR_EL2) & HCR_AMO; } diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index caf80c324b35..4bb877e4280f 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -2173,16 +2173,29 @@ static int set_id_aa64pfr1_el1(struct kvm_vcpu *vcpu, return set_id_reg(vcpu, rd, user_val); } +/* + * Allow userspace to de-feature a stage-2 translation granule but prevent it + * from claiming the impossible. + */ +#define tgran2_val_allowed(tg, safe, user) \ +({ \ + u8 __s = SYS_FIELD_GET(ID_AA64MMFR0_EL1, tg, safe); \ + u8 __u = SYS_FIELD_GET(ID_AA64MMFR0_EL1, tg, user); \ + \ + __s == __u || __u == ID_AA64MMFR0_EL1_##tg##_NI; \ +}) + static int set_id_aa64mmfr0_el1(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, u64 user_val) { u64 sanitized_val = kvm_read_sanitised_id_reg(vcpu, rd); - u64 tgran2_mask = ID_AA64MMFR0_EL1_TGRAN4_2_MASK | - ID_AA64MMFR0_EL1_TGRAN16_2_MASK | - ID_AA64MMFR0_EL1_TGRAN64_2_MASK; - if (vcpu_has_nv(vcpu) && - ((sanitized_val & tgran2_mask) != (user_val & tgran2_mask))) + if (!vcpu_has_nv(vcpu)) + return set_id_reg(vcpu, rd, user_val); + + if (!tgran2_val_allowed(TGRAN4_2, sanitized_val, user_val) || + !tgran2_val_allowed(TGRAN16_2, sanitized_val, user_val) || + !tgran2_val_allowed(TGRAN64_2, sanitized_val, user_val)) return -EINVAL; return set_id_reg(vcpu, rd, user_val); |