From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752227AbbIOHwt (ORCPT ); Tue, 15 Sep 2015 03:52:49 -0400 Received: from e06smtp16.uk.ibm.com ([195.75.94.112]:58020 "EHLO e06smtp16.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751480AbbIOHwr (ORCPT ); Tue, 15 Sep 2015 03:52:47 -0400 X-Helo: d06dlp01.portsmouth.uk.ibm.com X-MailFrom: cornelia.huck@de.ibm.com X-RcptTo: stable@vger.kernel.org Date: Tue, 15 Sep 2015 09:52:35 +0200 From: Cornelia Huck To: Jason Wang Cc: gleb@kernel.org, pbonzini@redhat.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, mst@redhat.com, stable@vger.kernel.org Subject: Re: [PATCH V6 4/6] kvm: fix zero length mmio searching Message-ID: <20150915095235.1333ab5f.cornelia.huck@de.ibm.com> In-Reply-To: <1442299319-5253-5-git-send-email-jasowang@redhat.com> References: <1442299319-5253-1-git-send-email-jasowang@redhat.com> <1442299319-5253-5-git-send-email-jasowang@redhat.com> Organization: IBM Deutschland Research & Development GmbH Vorsitzende des Aufsichtsrats: Martina Koederitz =?UTF-8?B?R2VzY2jDpGZ0c2bDvGhydW5nOg==?= Dirk Wittkopp Sitz der Gesellschaft: =?UTF-8?B?QsO2Ymxpbmdlbg==?= Registergericht: Amtsgericht Stuttgart, HRB 243294 X-Mailer: Claws Mail 3.8.0 (GTK+ 2.24.10; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15091507-0025-0000-0000-000006DBDC3C Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 15 Sep 2015 14:41:57 +0800 Jason Wang wrote: > Currently, if we had a zero length mmio eventfd assigned on > KVM_MMIO_BUS. It will never be found by kvm_io_bus_cmp() since it > always compares the kvm_io_range() with the length that guest > wrote. This will cause e.g for vhost, kick will be trapped by qemu > userspace instead of vhost. Fixing this by using zero length if an > iodevice is zero length. > > Cc: stable@vger.kernel.org > Cc: Gleb Natapov > Cc: Paolo Bonzini > Signed-off-by: Jason Wang > --- > virt/kvm/kvm_main.c | 19 +++++++++++++++++-- > 1 file changed, 17 insertions(+), 2 deletions(-) Reviewed-by: Cornelia Huck