Do not skip invalid shadow pages when zapping obsolete pages if the pages' root_count has reached zero, in which case the page can be immediately zapped and freed. Update the comment accordingly. Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx> --- arch/x86/kvm/mmu.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index a7b14750cde9..5e41b1f77a6d 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -5692,11 +5692,12 @@ static void kvm_zap_obsolete_pages(struct kvm *kvm) break; /* - * Since we are reversely walking the list and the invalid - * list will be moved to the head, skip the invalid page - * can help us to avoid the infinity list walking. + * Skip invalid pages with a non-zero root count, zapping pages + * with a non-zero root count will never succeed, i.e. the page + * will get thrown back on active_mmu_pages and we'll get stuck + * in an infinite loop. */ - if (sp->role.invalid) + if (sp->role.invalid && sp->root_count) continue; /* -- 2.22.0
