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| author | Marc Zyngier <maz@kernel.org> | 2024-04-19 11:29:33 +0100 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2024-04-20 12:42:51 +0100 |
| commit | 213b3d1ea1612c6d26153be446923831c4534689 (patch) | |
| tree | 6af4149811aabce00ff6164041efbffadd4d141a /arch/arm64/kvm/emulate-nested.c | |
| parent | 6ccc971ee2c61a1ffb487e46bf6184f7df6aacfb (diff) | |
| download | linux-213b3d1ea1612c6d26153be446923831c4534689.tar.gz linux-213b3d1ea1612c6d26153be446923831c4534689.tar.bz2 linux-213b3d1ea1612c6d26153be446923831c4534689.zip | |
KVM: arm64: nv: Handle ERETA[AB] instructions
Now that we have some emulation in place for ERETA[AB], we can
plug it into the exception handling machinery.
As for a bare ERET, an "easy" ERETAx instruction is processed as
a fixup, while something that requires a translation regime
transition or an exception delivery is left to the slow path.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240419102935.1935571-14-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
Diffstat (limited to 'arch/arm64/kvm/emulate-nested.c')
| -rw-r--r-- | arch/arm64/kvm/emulate-nested.c | 22 |
1 files changed, 20 insertions, 2 deletions
diff --git a/arch/arm64/kvm/emulate-nested.c b/arch/arm64/kvm/emulate-nested.c index 63a74c0330f1..72d733c74a38 100644 --- a/arch/arm64/kvm/emulate-nested.c +++ b/arch/arm64/kvm/emulate-nested.c @@ -2172,7 +2172,7 @@ static u64 kvm_check_illegal_exception_return(struct kvm_vcpu *vcpu, u64 spsr) void kvm_emulate_nested_eret(struct kvm_vcpu *vcpu) { - u64 spsr, elr; + u64 spsr, elr, esr; /* * Forward this trap to the virtual EL2 if the virtual @@ -2181,12 +2181,30 @@ void kvm_emulate_nested_eret(struct kvm_vcpu *vcpu) if (forward_traps(vcpu, HCR_NV)) return; + /* Check for an ERETAx */ + esr = kvm_vcpu_get_esr(vcpu); + if (esr_iss_is_eretax(esr) && !kvm_auth_eretax(vcpu, &elr)) { + /* + * Oh no, ERETAx failed to authenticate. If we have + * FPACCOMBINE, deliver an exception right away. If we + * don't, then let the mangled ELR value trickle down the + * ERET handling, and the guest will have a little surprise. + */ + if (kvm_has_pauth(vcpu->kvm, FPACCOMBINE)) { + esr &= ESR_ELx_ERET_ISS_ERETA; + esr |= FIELD_PREP(ESR_ELx_EC_MASK, ESR_ELx_EC_FPAC); + kvm_inject_nested_sync(vcpu, esr); + return; + } + } + preempt_disable(); kvm_arch_vcpu_put(vcpu); spsr = __vcpu_sys_reg(vcpu, SPSR_EL2); spsr = kvm_check_illegal_exception_return(vcpu, spsr); - elr = __vcpu_sys_reg(vcpu, ELR_EL2); + if (!esr_iss_is_eretax(esr)) + elr = __vcpu_sys_reg(vcpu, ELR_EL2); trace_kvm_nested_eret(vcpu, elr, spsr); |