diff options
| -rw-r--r-- | arch/arm64/kvm/emulate-nested.c | 59 |
1 files changed, 56 insertions, 3 deletions
diff --git a/arch/arm64/kvm/emulate-nested.c b/arch/arm64/kvm/emulate-nested.c index 8a1cfcf553a2..ef46c2e45307 100644 --- a/arch/arm64/kvm/emulate-nested.c +++ b/arch/arm64/kvm/emulate-nested.c @@ -1892,9 +1892,61 @@ static enum trap_behaviour compute_trap_behaviour(struct kvm_vcpu *vcpu, return __compute_trap_behaviour(vcpu, tc.cgt, b); } -static bool check_fgt_bit(u64 val, const union trap_config tc) +static u64 kvm_get_sysreg_res0(struct kvm *kvm, enum vcpu_sysreg sr) { - return ((val >> tc.bit) & 1) == tc.pol; + struct kvm_sysreg_masks *masks; + + /* Only handle the VNCR-backed regs for now */ + if (sr < __VNCR_START__) + return 0; + + masks = kvm->arch.sysreg_masks; + + return masks->mask[sr - __VNCR_START__].res0; +} + +static bool check_fgt_bit(struct kvm *kvm, bool is_read, + u64 val, const union trap_config tc) +{ + enum vcpu_sysreg sr; + + if (tc.pol) + return (val & BIT(tc.bit)); + + /* + * FGTs with negative polarities are an absolute nightmare, as + * we need to evaluate the bit in the light of the feature + * that defines it. WTF were they thinking? + * + * So let's check if the bit has been earmarked as RES0, as + * this indicates an unimplemented feature. + */ + if (val & BIT(tc.bit)) + return false; + + switch ((enum fgt_group_id)tc.fgt) { + case HFGxTR_GROUP: + sr = is_read ? HFGRTR_EL2 : HFGWTR_EL2; + break; + + case HDFGRTR_GROUP: + sr = is_read ? HDFGRTR_EL2 : HDFGWTR_EL2; + break; + + case HAFGRTR_GROUP: + sr = HAFGRTR_EL2; + break; + + case HFGITR_GROUP: + sr = HFGITR_EL2; + break; + + default: + WARN_ONCE(1, "Unhandled FGT group"); + return false; + } + + return !(kvm_get_sysreg_res0(kvm, sr) & BIT(tc.bit)); } bool __check_nv_sr_forward(struct kvm_vcpu *vcpu) @@ -1969,7 +2021,8 @@ bool __check_nv_sr_forward(struct kvm_vcpu *vcpu) return false; } - if (tc.fgt != __NO_FGT_GROUP__ && check_fgt_bit(val, tc)) + if (tc.fgt != __NO_FGT_GROUP__ && check_fgt_bit(vcpu->kvm, is_read, + val, tc)) goto inject; b = compute_trap_behaviour(vcpu, tc); |