Re: [PATCH v2 2/2] RISC-V: KVM: Fix skip of valid pages in kvm_riscv_gstage_unmap_range
From: Anup Patel
Date: Sun Jun 07 2026 - 02:21:21 EST
On Fri, Jun 5, 2026 at 4:33 AM <atwufei@xxxxxxx> wrote:
>
> From: Wu Fei <wu.fei9@xxxxxxxxxxxxxxxx>
>
> Same as kvm_riscv_gstage_wp_range, the possible valid pages should not
> be skipped if !found_leaf. Different from wp case, which can
> write-protect more than asked, unmap can't do that, no splitting is
> added right now but a warning is logged instead.
>
> Signed-off-by: Wu Fei <wu.fei9@xxxxxxxxxxxxxxxx>
LGTM.
Reviewed-by: Anup Patel <anup@xxxxxxxxxxxxxx>
Queued this patch for Linux-7.2
Thanks,
Anup
> ---
> arch/riscv/kvm/gstage.c | 20 ++++++++++++--------
> 1 file changed, 12 insertions(+), 8 deletions(-)
>
> diff --git a/arch/riscv/kvm/gstage.c b/arch/riscv/kvm/gstage.c
> index 2b141a78ecac..d78f5aeb8b40 100644
> --- a/arch/riscv/kvm/gstage.c
> +++ b/arch/riscv/kvm/gstage.c
> @@ -395,15 +395,19 @@ void kvm_riscv_gstage_unmap_range(struct kvm_gstage *gstage,
> if (ret)
> break;
>
> - if (!found_leaf)
> - goto next;
> -
> - if (!(addr & (page_size - 1)) && ((end - addr) >= page_size))
> - kvm_riscv_gstage_op_pte(gstage, addr, ptep,
> - ptep_level, GSTAGE_OP_CLEAR);
> + if (!found_leaf) {
> + addr = ALIGN(addr + 1, page_size);
> + } else {
> + if (!(addr & (page_size - 1)) && ((end - addr) >= page_size))
> + kvm_riscv_gstage_op_pte(gstage, addr, ptep,
> + ptep_level, GSTAGE_OP_CLEAR);
> + else {
> + WARN_ONCE(1, "Skip unmap range addr: %#llx, end: %#llx, page_size: %#lx\n",
> + addr, end, page_size);
> + }
>
> -next:
> - addr += page_size;
> + addr += page_size;
> + }
>
> /*
> * If the range is too large, release the kvm->mmu_lock
> --
> 2.51.0
>