[PATCH] RISC-V: KVM: Avoid re-acquiring memslot in kvm_riscv_gstage_map()

[Anup Patel]

On Wed, Jun 11, 2025 at 3:30 PM <zhouquan at iscas.ac.cn> wrote:
>
> From: Quan Zhou <zhouquan at iscas.ac.cn>
>
> The caller has already passed in the memslot, and there are
> two instances `{kvm_faultin_pfn/mark_page_dirty}` of retrieving
> the memslot again in `kvm_riscv_gstage_map`, we can replace them
> with `{__kvm_faultin_pfn/mark_page_dirty_in_slot}`.
>
> Signed-off-by: Quan Zhou <zhouquan at iscas.ac.cn>

LGTM.

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

Queued this patch for Linux-6.17

Thanks,
Anup

> ---
>  arch/riscv/kvm/mmu.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c
> index 1087ea74567b..f9059dac3ba3 100644
> --- a/arch/riscv/kvm/mmu.c
> +++ b/arch/riscv/kvm/mmu.c
> @@ -648,7 +648,8 @@ int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu,
>                 return -EFAULT;
>         }
>
> -       hfn = kvm_faultin_pfn(vcpu, gfn, is_write, &writable, &page);
> +       hfn = __kvm_faultin_pfn(memslot, gfn, is_write ? FOLL_WRITE : 0,
> +                               &writable, &page);
>         if (hfn == KVM_PFN_ERR_HWPOISON) {
>                 send_sig_mceerr(BUS_MCEERR_AR, (void __user *)hva,
>                                 vma_pageshift, current);
> @@ -670,7 +671,7 @@ int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu,
>                 goto out_unlock;
>
>         if (writable) {
> -               mark_page_dirty(kvm, gfn);
> +               mark_page_dirty_in_slot(kvm, memslot, gfn);
>                 ret = gstage_map_page(kvm, pcache, gpa, hfn << PAGE_SHIFT,
>                                       vma_pagesize, false, true);
>         } else {
> --
> 2.34.1
>