Re: [PATCH] KVM: x86/mmu: Check every prev_roots in __kvm_mmu_free_obsolete_roots()

[Greg KH <gregkh@linuxfoundation.org>]

On Mon, Jun 06, 2022 at 05:46:36PM -0600, shaoqin.huang@intel.com wrote:
> From: Shaoqin Huang <shaoqin.huang@intel.com>
> 
> When freeing obsolete previous roots, check prev_roots as intended, not
> the current root.
> 
> Signed-off-by: Shaoqin Huang <shaoqin.huang@intel.com>
> Fixes: 527d5cd7eece ("KVM: x86/mmu: Zap only obsolete roots if a root shadow page is zapped")
> Cc: stable@vger.kernel.org
> ---
>  arch/x86/kvm/mmu/mmu.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
> index f4653688fa6d..e826ee9138fa 100644
> --- a/arch/x86/kvm/mmu/mmu.c
> +++ b/arch/x86/kvm/mmu/mmu.c
> @@ -5179,7 +5179,7 @@ static void __kvm_mmu_free_obsolete_roots(struct kvm *kvm, struct kvm_mmu *mmu)
>  		roots_to_free |= KVM_MMU_ROOT_CURRENT;
>  
>  	for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++) {
> -		if (is_obsolete_root(kvm, mmu->root.hpa))
> +		if (is_obsolete_root(kvm, mmu->prev_roots[i].hpa))
>  			roots_to_free |= KVM_MMU_ROOT_PREVIOUS(i);
>  	}
>  
> -- 
> 2.30.2
>


<formletter>

This is not the correct way to submit patches for inclusion in the
stable kernel tree.  Please read:
    https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
for how to do this properly.

</formletter>