From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCHv2] KVM: prevent spurious exit to userspace during task switch emulation. Date: Thu, 15 Apr 2010 13:10:23 +0300 Message-ID: <4BC6E60F.5080306@redhat.com> References: <20100415100905.GA4550@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: kvm@vger.kernel.org, mtosatti@redhat.com To: Gleb Natapov Return-path: Received: from mx1.redhat.com ([209.132.183.28]:61636 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751863Ab0DOKK1 (ORCPT ); Thu, 15 Apr 2010 06:10:27 -0400 Received: from int-mx05.intmail.prod.int.phx2.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.18]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o3FAARkJ001885 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Thu, 15 Apr 2010 06:10:27 -0400 In-Reply-To: <20100415100905.GA4550@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On 04/15/2010 01:09 PM, Gleb Natapov wrote: > > If kvm_task_switch() fails code exits to userspace without specifying > exit reason, so the previous exit reason is reused by userspace. Fix > this by specifying exit reason correctly. > > --- > Changelog: > v1->v2: > - report emulation error to userspace instead of ignoring it silently. > > Yeah, better than logging to dmesg. -- I have a truly marvellous patch that fixes the bug which this signature is too narrow to contain.