Re: [PATCH 1/3] RISC-V: KVM: Redirect instruction access fault trap to guest

From: Anup Patel
Date: Mon Dec 23 2024 - 08:51:20 EST


On Fri, Dec 13, 2024 at 2:26 AM Atish Patra <atishp@xxxxxxxxxxxx> wrote:
>
> From: Quan Zhou <zhouquan@xxxxxxxxxxx>
>
> The M-mode redirects an unhandled instruction access
> fault trap back to S-mode when not delegating it to
> VS-mode(hedeleg). However, KVM running in HS-mode
> terminates the VS-mode software when back from M-mode.
>
> The KVM should redirect the trap back to VS-mode, and
> let VS-mode trap handler decide the next step.
>
> Signed-off-by: Atish Patra <atishp@xxxxxxxxxxxx>
> Signed-off-by: Quan Zhou <zhouquan@xxxxxxxxxxx>

LGTM.

Reviewed-by: Anup Patel <anup@xxxxxxxxxxxxxx>

Regards,
Anup

> ---
> arch/riscv/kvm/vcpu_exit.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/riscv/kvm/vcpu_exit.c b/arch/riscv/kvm/vcpu_exit.c
> index fa98e5c024b2..c9f8b2094554 100644
> --- a/arch/riscv/kvm/vcpu_exit.c
> +++ b/arch/riscv/kvm/vcpu_exit.c
> @@ -187,6 +187,7 @@ int kvm_riscv_vcpu_exit(struct kvm_vcpu *vcpu, struct kvm_run *run,
> case EXC_STORE_MISALIGNED:
> case EXC_LOAD_ACCESS:
> case EXC_STORE_ACCESS:
> + case EXC_INST_ACCESS:
> if (vcpu->arch.guest_context.hstatus & HSTATUS_SPV) {
> kvm_riscv_vcpu_trap_redirect(vcpu, trap);
> ret = 1;
>
> --
> 2.34.1
>