From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:60794) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QRm57-0001Hd-Bb for qemu-devel@nongnu.org; Wed, 01 Jun 2011 10:07:38 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1QRm55-0006Aw-HC for qemu-devel@nongnu.org; Wed, 01 Jun 2011 10:07:32 -0400 Received: from mx1.redhat.com ([209.132.183.28]:26374) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QRm54-0006Al-RQ for qemu-devel@nongnu.org; Wed, 01 Jun 2011 10:07:31 -0400 Date: Wed, 1 Jun 2011 11:07:25 -0300 From: Luiz Capitulino Message-ID: <20110601110725.167405fc@doriath> In-Reply-To: <4DE64690.8020500@redhat.com> References: <1305808412-16994-1-git-send-email-kwolf@redhat.com> <1305808412-16994-6-git-send-email-kwolf@redhat.com> <20110526181208.46aba2ae@doriath> <20110601104456.5469329b@doriath> <4DE64690.8020500@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 05/18] ide: Turn debug messages into assertions List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Kevin Wolf Cc: Stefan Hajnoczi , qemu-devel@nongnu.org On Wed, 01 Jun 2011 16:02:56 +0200 Kevin Wolf wrote: > Am 01.06.2011 15:44, schrieb Luiz Capitulino: > > On Thu, 26 May 2011 18:12:08 -0300 > > Luiz Capitulino wrote: > > > >> On Thu, 19 May 2011 14:33:19 +0200 > >> Kevin Wolf wrote: > >> > >>> These printfs aren't really debug messages, but clearly indicate a bug if they > >>> ever become effective. > >> > >> Then we have a bug somewhere, starting a VM with: > >> > >> # qemu -hda disks/test.img -enable-kvm -m 1G -cdrom /dev/sr0 > >> > >> Where the host's CDROM is empty, triggers one of these asserts: > >> > >> qmp-unstable/hw/ide/pci.c:299: bmdma_cmd_writeb: Assertion `bm->bus->dma->aiocb == ((void *)0)' > > > > I found out why this is happening. I'm passing '-snapshot' to the command-line, > > sorry for not mentioning it (I forgot I was using my devel alias). > > And suddenly it's reproducible. :-) > > I'll have a look. Thanks. > > I also found out that /usr/bin/eject in the guest won't work when > > -snapshot is used. Shouldn't qemu ignore this flag when using cdrom > > passthrough? > > "Won't work" means that it works like with a CD-ROM image? I guess so. > That would be > what I expect, as you end up having a qcow2 image with -snapshot. > > Not sure what's the best way of fixing this. Maybe just ignoring > -snapshot for read-only block devices? I think that makes sense as the reason to use -snapshot is to avoid writing to the image/device. > Or we could try and forward the > eject request to the backing file if the format driver doesn't handle it. > > Kevin >