Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754465AbXJULKv (ORCPT ); Sun, 21 Oct 2007 07:10:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751831AbXJULIA (ORCPT ); Sun, 21 Oct 2007 07:08:00 -0400 Received: from il.qumranet.com ([82.166.9.18]:58447 "EHLO il.qumranet.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751502AbXJULHz (ORCPT ); Sun, 21 Oct 2007 07:07:55 -0400 From: Avi Kivity To: kvm-devel@lists.sourceforge.net Cc: linux-kernel@vger.kernel.org, Laurent Vivier , Avi Kivity Subject: [PATCH 09/11] KVM: Move kvm_guest_exit() after local_irq_enable() Date: Sun, 21 Oct 2007 13:08:10 +0200 Message-Id: <11929648921683-git-send-email-avi@qumranet.com> X-Mailer: git-send-email 1.5.3 In-Reply-To: <1192964892617-git-send-email-avi@qumranet.com> References: <1192964892617-git-send-email-avi@qumranet.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1313 Lines: 48 From: Laurent Vivier We need to make sure that the timer interrupt happens before we clear PF_VCPU, so the accounting code actually sees guest mode. http://lkml.org/lkml/2007/10/15/114 Signed-off-by: Laurent Vivier Signed-off-by: Avi Kivity --- drivers/kvm/kvm_main.c | 11 ++++++++++- 1 files changed, 10 insertions(+), 1 deletions(-) diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c index af2d288..8c458f2 100644 --- a/drivers/kvm/kvm_main.c +++ b/drivers/kvm/kvm_main.c @@ -2054,12 +2054,21 @@ again: kvm_x86_ops->run(vcpu, kvm_run); - kvm_guest_exit(); vcpu->guest_mode = 0; local_irq_enable(); ++vcpu->stat.exits; + /* + * We must have an instruction between local_irq_enable() and + * kvm_guest_exit(), so the timer interrupt isn't delayed by + * the interrupt shadow. The stat.exits increment will do nicely. + * But we need to prevent reordering, hence this barrier(): + */ + barrier(); + + kvm_guest_exit(); + preempt_enable(); /* -- 1.5.3 - 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/