From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:58378) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1T1NRi-0004kN-2Z for qemu-devel@nongnu.org; Tue, 14 Aug 2012 16:10:35 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1T1NRg-0003XJ-5B for qemu-devel@nongnu.org; Tue, 14 Aug 2012 16:10:34 -0400 Received: from mail.linux-iscsi.org ([67.23.28.174]:33846 helo=linux-iscsi.org) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1T1NRg-0003X5-0T for qemu-devel@nongnu.org; Tue, 14 Aug 2012 16:10:32 -0400 From: "Nicholas A. Bellinger" In-Reply-To: <20120813181705.GC19460@redhat.com> References: <1344846917-7411-1-git-send-email-nab@linux-iscsi.org> <1344846917-7411-2-git-send-email-nab@linux-iscsi.org> <5028EDB2.10506@siemens.com> <20120813180312.GA19379@redhat.com> <50294219.3080800@siemens.com> <20120813181705.GC19460@redhat.com> Content-Type: text/plain; charset="UTF-8" Date: Tue, 14 Aug 2012 13:10:22 -0700 Message-ID: <1344975022.22433.83.camel@haakon2.linux-iscsi.org> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [RFC-v2 1/6] msix: Work-around for vhost-scsi with KVM in-kernel MSI injection List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Michael S. Tsirkin" Cc: Anthony Liguori , Stefan Hajnoczi , kvm-devel , Jan Kiszka , qemu-devel , Zhi Yong Wu , Anthony Liguori , target-devel , Hannes Reinecke , Paolo Bonzini , lf-virt , Christoph Hellwig On Mon, 2012-08-13 at 21:17 +0300, Michael S. Tsirkin wrote: > On Mon, Aug 13, 2012 at 08:06:17PM +0200, Jan Kiszka wrote: > > On 2012-08-13 20:03, Michael S. Tsirkin wrote: > > > On Mon, Aug 13, 2012 at 02:06:10PM +0200, Jan Kiszka wrote: > > >> On 2012-08-13 10:35, Nicholas A. Bellinger wrote: > > >>> From: Nicholas Bellinger > > >>> > > >>> This is required to get past the following assert with: > > >>> > > >>> commit 1523ed9e1d46b0b54540049d491475ccac7e6421 > > >>> Author: Jan Kiszka > > >>> Date: Thu May 17 10:32:39 2012 -0300 > > >>> > > >>> virtio/vhost: Add support for KVM in-kernel MSI injection > > >>> > > >>> Cc: Stefan Hajnoczi > > >>> Cc: Jan Kiszka > > >>> Cc: Paolo Bonzini > > >>> Cc: Anthony Liguori > > >>> Signed-off-by: Nicholas Bellinger > > >>> --- > > >>> hw/msix.c | 3 +++ > > >>> 1 files changed, 3 insertions(+), 0 deletions(-) > > >>> > > >>> diff --git a/hw/msix.c b/hw/msix.c > > >>> index 800fc32..c1e6dc3 100644 > > >>> --- a/hw/msix.c > > >>> +++ b/hw/msix.c > > >>> @@ -544,6 +544,9 @@ void msix_unset_vector_notifiers(PCIDevice *dev) > > >>> { > > >>> int vector; > > >>> > > >>> + if (!dev->msix_vector_use_notifier && !dev->msix_vector_release_notifier) > > >>> + return; > > >>> + > > >>> assert(dev->msix_vector_use_notifier && > > >>> dev->msix_vector_release_notifier); > > >>> > > >>> > > >> > > >> I think to remember pointing out that there is a bug somewhere in the > > >> reset code which deactivates a non-active vhost instance, no? > > >> > > >> Jan > > > > > > Could not find it. Could you dig it up pls? > > > > http://thread.gmane.org/gmane.linux.scsi.target.devel/2277/focus=2309 > > > > Jan > > Ah yes. So let's not work around, need to get to the bottom of that. > Ok, so the assert being triggered in msix_unset_vector_notifiers() appears to have been a side effect of the memory corruption bug in virtio-scsi fixed in Patch #6, and is no longer required to start vhost-scsi with the bugfix in place. That said, dropping this patch for RFC-v3..