From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53387) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fQer5-0003WN-Vy for qemu-devel@nongnu.org; Wed, 06 Jun 2018 16:16:29 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fQer4-0005aH-Tv for qemu-devel@nongnu.org; Wed, 06 Jun 2018 16:16:27 -0400 References: <20180606193702.7113-1-mreitz@redhat.com> From: John Snow Message-ID: Date: Wed, 6 Jun 2018 16:16:20 -0400 MIME-Version: 1.0 In-Reply-To: <20180606193702.7113-1-mreitz@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v2 0/3] qcow2: Do not mark inactive images corrupt List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Max Reitz , qemu-block@nongnu.org Cc: Kevin Wolf , Jeff Cody , qemu-devel@nongnu.org, qemu-stable On 06/06/2018 03:36 PM, Max Reitz wrote: > The non-public logs in > https://bugzilla.redhat.com/show_bug.cgi?id=1583346 (sorry...) reveal > this problem: > > $ (Create a qcow2 file "foo.qcow2" with a corrupted first L1 entry) > $ echo 'qemu-io none0 "read 0 512"' \ > | x86_64-softmmu/qemu-system-x86_64 -drive if=none,file=foo.qcow2 \ > -monitor stdio \ > -incoming exec:'cat /dev/null' > QEMU 2.12.50 monitor - type 'help' for more information > (qemu) qemu-io none0 "read 0 512" > qcow2: Marking image as corrupt: L2 table offset 0x44200 unaligned (L1 index: 0); further corruption events will be suppressed > qemu-system-x86_64: block/io.c:1691: bdrv_co_pwritev: Assertion `!(bs->open_flags & BDRV_O_INACTIVE)' failed. > [1] 18444 done echo 'qemu-io none0 "read 0 512"' | > 18445 abort (core dumped) x86_64-softmmu/qemu-system-x86_64 -drive if=none,file=foo.qcow2 -monitor stdi > > Oops. > > > The first patch in this series makes a function public that the second > patch uses to fix the issue by treating all non-writable images like > read-only images (yes, there is a difference...) in this regard (which > most importantly means not trying to set the corrupt flag on them). > Inactive images count as non-writable images, but not as read-only > images, so that fixes it. > > The third patch adds an iotest case. > > > v2: > - Use bdrv_is_writable() instead of copying its functionality [Jeff] > > > git-backport-diff against v1: > > Key: > [----] : patches are identical > [####] : number of functional differences between upstream/downstream patch > [down] : patch is downstream-only > The flags [FC] indicate (F)unctional and (C)ontextual differences, respectively > > 001/3:[down] 'block: Make bdrv_is_writable() public' > 002/3:[0004] [FC] 'qcow2: Do not mark inactive images corrupt' > 003/3:[----] [--] 'iotests: Add case for a corrupted inactive image' > > > Max Reitz (3): > block: Make bdrv_is_writable() public > qcow2: Do not mark inactive images corrupt > iotests: Add case for a corrupted inactive image > > include/block/block.h | 1 + > block.c | 17 ++++++++++++++--- > block/qcow2.c | 2 +- > tests/qemu-iotests/060 | 30 ++++++++++++++++++++++++++++++ > tests/qemu-iotests/060.out | 14 ++++++++++++++ > 5 files changed, 60 insertions(+), 4 deletions(-) > Reviewed-by: John Snow