From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43378) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a5sdJ-0005mv-D3 for qemu-devel@nongnu.org; Mon, 07 Dec 2015 05:03:02 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1a5sdE-0004Bd-Dl for qemu-devel@nongnu.org; Mon, 07 Dec 2015 05:03:01 -0500 Received: from e06smtp05.uk.ibm.com ([195.75.94.101]:49714) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a5sdE-0004BZ-4b for qemu-devel@nongnu.org; Mon, 07 Dec 2015 05:02:56 -0500 Received: from localhost by e06smtp05.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 7 Dec 2015 10:02:55 -0000 Received: from b06cxnps4075.portsmouth.uk.ibm.com (d06relay12.portsmouth.uk.ibm.com [9.149.109.197]) by d06dlp02.portsmouth.uk.ibm.com (Postfix) with ESMTP id 4B069219004D for ; Mon, 7 Dec 2015 10:02:46 +0000 (GMT) Received: from d06av01.portsmouth.uk.ibm.com (d06av01.portsmouth.uk.ibm.com [9.149.37.212]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id tB7A2r7E7012862 for ; Mon, 7 Dec 2015 10:02:53 GMT Received: from d06av01.portsmouth.uk.ibm.com (localhost [127.0.0.1]) by d06av01.portsmouth.uk.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id tB7A2rSH019297 for ; Mon, 7 Dec 2015 03:02:53 -0700 Date: Mon, 7 Dec 2015 11:02:51 +0100 From: Cornelia Huck Message-ID: <20151207110251.6391b306.cornelia.huck@de.ibm.com> In-Reply-To: <1449118802-12047-3-git-send-email-stefanha@redhat.com> References: <1449118802-12047-1-git-send-email-stefanha@redhat.com> <1449118802-12047-3-git-send-email-stefanha@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PULL for-2.5 2/4] block: Don't wait serialising for non-COR read requests List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefan Hajnoczi Cc: Peter Maydell , Fam Zheng , qemu-devel@nongnu.org On Thu, 3 Dec 2015 13:00:00 +0800 Stefan Hajnoczi wrote: > From: Fam Zheng > > The assertion problem was noticed in 06c3916b35a, but it wasn't > completely fixed, because even though the req is not marked as > serialising, it still gets serialised by wait_serialising_requests > against other serialising requests, which could lead to the same > assertion failure. > > Fix it by even more explicitly skipping the serialising for this > specific case. > > Signed-off-by: Fam Zheng > Message-id: 1448962590-2842-2-git-send-email-famz@redhat.com > Signed-off-by: Stefan Hajnoczi > --- > block/backup.c | 2 +- > block/io.c | 12 +++++++----- > include/block/block.h | 4 ++-- > trace-events | 2 +- > 4 files changed, 11 insertions(+), 9 deletions(-) This one causes segfaults for me: Program received signal SIGSEGV, Segmentation fault. bdrv_is_inserted (bs=0x800000000000) at /data/git/yyy/qemu/block.c:3071 3071 if (!drv) { (gdb) bt #0 bdrv_is_inserted (bs=0x800000000000) at /data/git/yyy/qemu/block.c:3071 #1 0x0000000080216974 in blk_is_inserted (blk=) at /data/git/yyy/qemu/block/block-backend.c:986 #2 0x00000000802169c6 in blk_is_available (blk=blk@entry=0x3ffb17e7960) at /data/git/yyy/qemu/block/block-backend.c:991 #3 0x0000000080216d12 in blk_check_byte_request (blk=blk@entry=0x3ffb17e7960, offset=offset@entry=4928966656, size=16384) at /data/git/yyy/qemu/block/block-backend.c:558 #4 0x0000000080216df2 in blk_check_request (blk=blk@entry=0x3ffb17e7960, sector_num=sector_num@entry=9626888, nb_sectors=nb_sectors@entry=32) at /data/git/yyy/qemu/block/block-backend.c:589 #5 0x0000000080217ee8 in blk_aio_readv (blk=0x3ffb17e7960, sector_num= 9626888, iov=0x8098c658, nb_sectors=, cb= 0x80081150 , opaque=0x80980620) at /data/git/yyy/qemu/block/block-backend.c:727 #6 0x000000008008186e in submit_requests (niov=, num_reqs=, start=, mrb=, blk=) at /data/git/yyy/qemu/hw/block/virtio-blk.c:366 #7 virtio_blk_submit_multireq (mrb=, blk=) at /data/git/yyy/qemu/hw/block/virtio-blk.c:444 #8 virtio_blk_submit_multireq (blk=0x3ffb17e7960, mrb=0x3ffffffeb58) at /data/git/yyy/qemu/hw/block/virtio-blk.c:389 #9 0x00000000800823ee in virtio_blk_handle_output (vdev=, vq=) at /data/git/yyy/qemu/hw/block/virtio-blk.c:615 #10 0x00000000801e367e in aio_dispatch (ctx=0x80918520) at /data/git/yyy/qemu/aio-posix.c:326 #11 0x00000000801d28b0 in aio_ctx_dispatch (source=, callback=, user_data=) at /data/git/yyy/qemu/async.c:231 #12 0x000003fffd36a05a in g_main_context_dispatch () from /lib64/libglib-2.0.so.0 #13 0x00000000801e0ffa in glib_pollfds_poll () at /data/git/yyy/qemu/main-loop.c:211 #14 os_host_main_loop_wait (timeout=) at /data/git/yyy/qemu/main-loop.c:256 #15 main_loop_wait (nonblocking=) at /data/git/yyy/qemu/main-loop.c:504 #16 0x00000000800148a6 in main_loop () at /data/git/yyy/qemu/vl.c:1923 #17 main (argc=, argv=, envp=) at /data/git/yyy/qemu/vl.c:4684 Relevant part of command line: -drive file=/dev/sda,if=none,id=drive-virtio-disk0,format=raw,serial=ccwzfcp1,cache=none -device virtio-blk-ccw,devno=fe.0.0001,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1,scsi=off