[RESEND PATCH 2/2] RISC-V: KVM: Propagate interrupted G-stage faults

[Anup Patel]

On Mon, Aug 10, 2026 at 10:46 AM Xie Bo <xb at ultrarisc.com> wrote:
>
> __kvm_faultin_pfn() reports an interrupted host page fault with
> KVM_PFN_ERR_SIGPENDING. RISC-V currently handles it as a generic error PFN
> and returns -EFAULT.
>
> Return -EINTR for the signal-pending sentinel so callers can distinguish
> an interrupted fault from an invalid userspace mapping. Do not log the
> expected interruption as a vCPU exit error.
>
> Fixes: 9d05c1fee837 ("RISC-V: KVM: Implement stage2 page table programming")
> Cc: stable at vger.kernel.org
> Signed-off-by: Xie Bo <xb at ultrarisc.com>

LGTM.

Reviewed-by: Anup Patel <anup at brainfault.org>

Queued this as a fix for Linux-7.3-rcX

Thanks,
Anup


> ---
>  arch/riscv/kvm/mmu.c       | 2 ++
>  arch/riscv/kvm/vcpu_exit.c | 2 +-
>  2 files changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c
> index d189fd5..3e955d8 100644
> --- a/arch/riscv/kvm/mmu.c
> +++ b/arch/riscv/kvm/mmu.c
> @@ -708,6 +708,8 @@ int kvm_riscv_mmu_map(struct kvm_vcpu *vcpu, struct kvm_memory_slot *memslot,
>                                 vma_pageshift, current);
>                 return 0;
>         }
> +       if (is_sigpending_pfn(hfn))
> +               return -EINTR;
>         if (is_error_noslot_pfn(hfn))
>                 return -EFAULT;
>
> diff --git a/arch/riscv/kvm/vcpu_exit.c b/arch/riscv/kvm/vcpu_exit.c
> index 88e0c36..8d36eb8 100644
> --- a/arch/riscv/kvm/vcpu_exit.c
> +++ b/arch/riscv/kvm/vcpu_exit.c
> @@ -283,7 +283,7 @@ int kvm_riscv_vcpu_exit(struct kvm_vcpu *vcpu, struct kvm_run *run,
>         }
>
>         /* Print details in-case of error */
> -       if (ret < 0) {
> +       if (ret < 0 && ret != -EINTR) {
>                 kvm_err("VCPU exit error %d\n", ret);
>                 kvm_err("SEPC=0x%lx SSTATUS=0x%lx HSTATUS=0x%lx\n",
>                         vcpu->arch.guest_context.sepc,
>