From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48461) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bIVsZ-0002qY-4r for qemu-devel@nongnu.org; Thu, 30 Jun 2016 02:55:16 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bIVsT-0006fG-6F for qemu-devel@nongnu.org; Thu, 30 Jun 2016 02:55:14 -0400 Received: from mx1.redhat.com ([209.132.183.28]:52988) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bIVsT-0006et-0c for qemu-devel@nongnu.org; Thu, 30 Jun 2016 02:55:09 -0400 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 3DDA37DCEA for ; Thu, 30 Jun 2016 06:55:08 +0000 (UTC) Date: Thu, 30 Jun 2016 08:55:05 +0200 From: Igor Mammedov Message-ID: <20160630085505.54ecccfc@nial.brq.redhat.com> In-Reply-To: <87y45nntuf.fsf@dusky.pond.sub.org> References: <1467102269-11112-1-git-send-email-imammedo@redhat.com> <87vb0sw45k.fsf@dusky.pond.sub.org> <20160629183612.45733386@igors-macbook-pro.local> <87y45nntuf.fsf@dusky.pond.sub.org> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] virtio: abort on fatal error instead of just exiting List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Markus Armbruster Cc: qemu-devel@nongnu.org, mst@redhat.com On Thu, 30 Jun 2016 07:12:08 +0200 Markus Armbruster wrote: > Igor Mammedov writes: > > > On Wed, 29 Jun 2016 14:49:59 +0200 > > Markus Armbruster wrote: > > > >> Igor Mammedov writes: > >> > >> > replace mainly useless exit(1) on fatal error path with > >> > abort(), so that it would be possible to generate core > >> > dump, that could be used to analyse cause of problem. > >> > > >> > Signed-off-by: Igor Mammedov > >> > --- > >> > hw/virtio/virtio.c | 24 ++++++++++++------------ > >> > 1 file changed, 12 insertions(+), 12 deletions(-) > >> > > >> > diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c > >> > index 7ed06ea..9d3ac72 100644 > >> > --- a/hw/virtio/virtio.c > >> > +++ b/hw/virtio/virtio.c > >> > @@ -315,7 +315,7 @@ static int virtqueue_num_heads(VirtQueue *vq, > >> > unsigned int idx) if (num_heads > vq->vring.num) { > >> > error_report("Guest moved used index from %u to %u", > >> > idx, vq->shadow_avail_idx); > >> > - exit(1); > >> > + abort(); > >> > >> What's wrong with a simple assert(num_heads <= vq->vring.num)? > > Nothing, it should work to as we don't use NDEBUG. > > My intent was to make core dump at the point and no to remove > > error message > > (though message's mostly useless for me as virtio is unfamiliar to me > > and I had to dig into core dump to analyze issue). > > Understand. > > The solution we really want is of course putting the device in an error > state, where it stays until reset. As Cornelia has mentioned earlier, there is/were a series on list for it, aborting is just an interim step until those patches are ready.