From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: [PATCH 43/58] KVM: MMU: Don't cache guest access bits in the shadow page table Date: Sun, 17 Jun 2007 12:44:24 +0300 Message-ID: <1182073481421-git-send-email-avi@qumranet.com> References: <1182073479890-git-send-email-avi@qumranet.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Return-path: In-Reply-To: <1182073479890-git-send-email-avi-atKUWr5tajBWk0Htik3J/w@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: kvm.vger.kernel.org This was once used to avoid accessing the guest pte when upgrading the shadow pte from read-only to read-write. But usually we need to set the guest pte dirty or accessed bits anyway, so this wasn't really exploited. Signed-off-by: Avi Kivity --- drivers/kvm/mmu.c | 8 -------- drivers/kvm/paging_tmpl.h | 1 - 2 files changed, 0 insertions(+), 9 deletions(-) diff --git a/drivers/kvm/mmu.c b/drivers/kvm/mmu.c index b47391f..986d012 100644 --- a/drivers/kvm/mmu.c +++ b/drivers/kvm/mmu.c @@ -97,14 +97,6 @@ static int dbg = 1; #define PT_SHADOW_PS_MARK (1ULL << PT_FIRST_AVAIL_BITS_SHIFT) #define PT_SHADOW_IO_MARK (1ULL << PT_FIRST_AVAIL_BITS_SHIFT) -#define PT_SHADOW_WRITABLE_SHIFT (PT_FIRST_AVAIL_BITS_SHIFT + 1) -#define PT_SHADOW_WRITABLE_MASK (1ULL << PT_SHADOW_WRITABLE_SHIFT) - -#define PT_SHADOW_USER_SHIFT (PT_SHADOW_WRITABLE_SHIFT + 1) -#define PT_SHADOW_USER_MASK (1ULL << (PT_SHADOW_USER_SHIFT)) - -#define PT_SHADOW_BITS_OFFSET (PT_SHADOW_WRITABLE_SHIFT - PT_WRITABLE_SHIFT) - #define VALID_PAGE(x) ((x) != INVALID_PAGE) #define PT64_LEVEL_BITS 9 diff --git a/drivers/kvm/paging_tmpl.h b/drivers/kvm/paging_tmpl.h index b17a4b7..adc1206 100644 --- a/drivers/kvm/paging_tmpl.h +++ b/drivers/kvm/paging_tmpl.h @@ -219,7 +219,6 @@ static void FNAME(set_pte_common)(struct kvm_vcpu *vcpu, spte |= PT_PRESENT_MASK | PT_ACCESSED_MASK | PT_DIRTY_MASK; spte |= *gpte & PT64_NX_MASK; - spte |= access_bits << PT_SHADOW_BITS_OFFSET; if (!dirty) access_bits &= ~PT_WRITABLE_MASK; -- 1.5.0.6 ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/