Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965028AbXADQUL (ORCPT ); Thu, 4 Jan 2007 11:20:11 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965015AbXADQUL (ORCPT ); Thu, 4 Jan 2007 11:20:11 -0500 Received: from il.qumranet.com ([62.219.232.206]:51755 "EHLO il.qumranet.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965033AbXADQUJ (ORCPT ); Thu, 4 Jan 2007 11:20:09 -0500 Subject: [PATCH 31/33] KVM: MMU: Flush guest tlb when reducing permissions on a pte From: Avi Kivity Date: Thu, 04 Jan 2007 16:20:07 -0000 To: kvm-devel@lists.sourceforge.net Cc: linux-kernel@vger.kernel.org, akpm@osdl.org, mingo@elte.hu References: <459D21DD.5090506@qumranet.com> In-Reply-To: <459D21DD.5090506@qumranet.com> Message-Id: <20070104162007.AF4E9250048@il.qumranet.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1514 Lines: 45 If we reduce permissions on a pte, we must flush the cached copy of the pte from the guest's tlb. This is implemented at the moment by flushing the entire guest tlb, and can be improved by flushing just the relevant virtual address, if it is known. Signed-off-by: Avi Kivity Index: linux-2.6/drivers/kvm/mmu.c =================================================================== --- linux-2.6.orig/drivers/kvm/mmu.c +++ linux-2.6/drivers/kvm/mmu.c @@ -383,6 +383,7 @@ static void rmap_write_protect(struct kv BUG_ON(!(*spte & PT_WRITABLE_MASK)); rmap_printk("rmap_write_protect: spte %p %llx\n", spte, *spte); rmap_remove(vcpu, spte); + kvm_arch_ops->tlb_flush(vcpu); *spte &= ~(u64)PT_WRITABLE_MASK; } } @@ -594,6 +595,7 @@ static void kvm_mmu_page_unlink_children rmap_remove(vcpu, &pt[i]); pt[i] = 0; } + kvm_arch_ops->tlb_flush(vcpu); return; } @@ -927,7 +929,10 @@ static inline void set_pte_common(struct pgprintk("%s: found shadow page for %lx, marking ro\n", __FUNCTION__, gfn); access_bits &= ~PT_WRITABLE_MASK; - *shadow_pte &= ~PT_WRITABLE_MASK; + if (is_writeble_pte(*shadow_pte)) { + *shadow_pte &= ~PT_WRITABLE_MASK; + kvm_arch_ops->tlb_flush(vcpu); + } } } - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/