From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49172) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bAEoJ-0004Va-4x for qemu-devel@nongnu.org; Tue, 07 Jun 2016 07:04:43 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bAEoD-0000LO-8A for qemu-devel@nongnu.org; Tue, 07 Jun 2016 07:04:39 -0400 References: <1464973388-15821-1-git-send-email-eblake@redhat.com> <1464973388-15821-6-git-send-email-eblake@redhat.com> <5751C32F.3040806@redhat.com> <5751F9E8.6090900@redhat.com> <20160607100810.GB4684@noname.str.redhat.com> From: Paolo Bonzini Message-ID: <03515d0b-afa7-0ba8-ee40-67ff78a72804@redhat.com> Date: Tue, 7 Jun 2016 13:04:17 +0200 MIME-Version: 1.0 In-Reply-To: <20160607100810.GB4684@noname.str.redhat.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH 5/5] block: Move request_alignment into BlockLimit List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Kevin Wolf , Eric Blake Cc: qemu-devel@nongnu.org, Fam Zheng , Ronnie Sahlberg , qemu-block@nongnu.org, Peter Lieven , mreitz@redhat.com, Stefan Hajnoczi On 07/06/2016 12:08, Kevin Wolf wrote: >>> > > Something in this patch is causing qemu-iotests 77 to infloop; we= may >>> > > decide it is just easier to drop this patch rather than find all = the >>> > > places where the request_alignment must be preserved across what >>> > > otherwise zeroes out limits. >> >=20 >> > Found it; squash this in (or use it as an argument why we don't want >> > request_alignment in bs->bl after all): > This hunk doesn't make sense to me. For the correctness of the code it > shouldn't make a difference whether the alignment happens before passin= g > the request to file/raw-posix or already in the raw format layer. >=20 > The cause for the hang you're seeing is probably that the request is > already aligned before the blkdebug layer and therefore the blkdebug > events aren't generated any more. That's a problem with the test (I'm > considering the blkdebug events part of the test infrastructure), > however, and not with the code. Perhaps you could add an alignment option to blkdebug (or in general options to force block limits on blkdebug), which would help testing in general? Thanks, Paolo