| Message ID | 20230815183903.2735724-25-maz@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: arm64: NV trap forwarding infrastructure | expand |
Hi Marc, On Tue, Aug 15, 2023 at 11:47 AM Marc Zyngier <maz@kernel.org> wrote: > > We already handle ERET being trapped from a L1 guest in hyp context. > However, with FGT, we can also have ERET being trapped from L2, and > this needs to be reinjected into L1. > > Add the required exception routing. > > Signed-off-by: Marc Zyngier <maz@kernel.org> > --- > arch/arm64/kvm/handle_exit.c | 17 ++++++++++++++++- > 1 file changed, 16 insertions(+), 1 deletion(-) > > diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c > index 3b86d534b995..617ae6dea5d5 100644 > --- a/arch/arm64/kvm/handle_exit.c > +++ b/arch/arm64/kvm/handle_exit.c > @@ -222,7 +222,22 @@ static int kvm_handle_eret(struct kvm_vcpu *vcpu) > if (kvm_vcpu_get_esr(vcpu) & ESR_ELx_ERET_ISS_ERET) > return kvm_handle_ptrauth(vcpu); > > - kvm_emulate_nested_eret(vcpu); > + /* > + * If we got here, two possibilities: > + * > + * - the guest is in EL2, and we need to fully emulate ERET > + * > + * - the guest is in EL1, and we need to reinject the > + * exception into the L1 hypervisor. > + * > + * If KVM ever traps ERET for its own use, we'll have to > + * revisit this. > + */ > + if (is_hyp_ctxt(vcpu)) > + kvm_emulate_nested_eret(vcpu); > + else > + kvm_inject_nested_sync(vcpu, kvm_vcpu_get_esr(vcpu)); > + > return 1; > } > > -- > 2.34.1 > Reviewed-by: Jing Zhang <jingzhangos@google.com> Jing
diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index 3b86d534b995..617ae6dea5d5 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -222,7 +222,22 @@ static int kvm_handle_eret(struct kvm_vcpu *vcpu) if (kvm_vcpu_get_esr(vcpu) & ESR_ELx_ERET_ISS_ERET) return kvm_handle_ptrauth(vcpu); - kvm_emulate_nested_eret(vcpu); + /* + * If we got here, two possibilities: + * + * - the guest is in EL2, and we need to fully emulate ERET + * + * - the guest is in EL1, and we need to reinject the + * exception into the L1 hypervisor. + * + * If KVM ever traps ERET for its own use, we'll have to + * revisit this. + */ + if (is_hyp_ctxt(vcpu)) + kvm_emulate_nested_eret(vcpu); + else + kvm_inject_nested_sync(vcpu, kvm_vcpu_get_esr(vcpu)); + return 1; }
We already handle ERET being trapped from a L1 guest in hyp context. However, with FGT, we can also have ERET being trapped from L2, and this needs to be reinjected into L1. Add the required exception routing. Signed-off-by: Marc Zyngier <maz@kernel.org> --- arch/arm64/kvm/handle_exit.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-)