From mboxrd@z Thu Jan 1 00:00:00 1970 From: Xiao Guangrong Subject: [PATCH 1/10] KVM: MMU: fix kvm_mmu_slot_remove_write_access Date: Fri, 04 Mar 2011 18:56:41 +0800 Message-ID: <4D70C569.1030107@cn.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Marcelo Tosatti , LKML , KVM To: Avi Kivity Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org Only remove write access in the last sptes Signed-off-by: Xiao Guangrong --- arch/x86/kvm/mmu.c | 9 +++++++-- 1 files changed, 7 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index b6a9963..b9bf016 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -3540,12 +3540,17 @@ void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot) pt = sp->spt; for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { - if (sp->role.level != PT_PAGE_TABLE_LEVEL - && is_large_pte(pt[i])) { + if (!is_shadow_present_pte(pt[i]) || + !is_last_spte(pt[i], sp->role.level)) + continue; + + if (is_large_pte(pt[i])) { drop_spte(kvm, &pt[i], shadow_trap_nonpresent_pte); --kvm->stat.lpages; + continue; } + /* avoid RMW */ if (is_writable_pte(pt[i])) update_spte(&pt[i], pt[i] & ~PT_WRITABLE_MASK); -- 1.7.4