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List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Well, that was a rollercoaster of emotions as I read your mails. On 3/24/20 9:33 AM, Dietmar Maurer wrote: > spoke too soon - the error is still there, sigh > >> This is fixed with this patch: >> >> https://lists.gnu.org/archive/html/qemu-devel/2020-03/msg07249.html >> >> thanks! >> >>> On March 24, 2020 12:13 PM Dietmar Maurer wrote: >>> >>> >>> I get a core dump with backup transactions when using io-threads. >>> >>> To reproduce, create and start a VM with: >>> >>> # qemu-img create disk1.raw 100M >>> # qemu-img create disk2.raw 100M >>> #./x86_64-softmmu/qemu-system-x86_64 -chardev 'socket,id=qmp,path=/var/run/qemu-test.qmp,server,nowait' -mon 'chardev=qmp,mode=control' -pidfile /var/run/qemu-server/108.pid -m 512 -object 'iothread,id=iothread-virtioscsi0' -object 'iothread,id=iothread-virtioscsi1' -device 'virtio-scsi-pci,id=virtioscsi0,iothread=iothread-virtioscsi0' -drive 'file=disk1.raw,if=none,id=drive-scsi0,format=raw,cache=none,aio=native,detect-zeroes=on' -device 'scsi-hd,bus=virtioscsi0.0,channel=0,scsi-id=0,lun=0,drive=drive-scsi0,id=scsi0' -device 'virtio-scsi-pci,id=virtioscsi1,iothread=iothread-virtioscsi1' -drive 'file=disk2.raw,if=none,id=drive-scsi1,format=raw,cache=none,aio=native,detect-zeroes=on' -device 'scsi-hd,bus=virtioscsi1.0,channel=0,scsi-id=0,lun=1,drive=drive-scsi1,id=scsi1' >>> >>> Then open socat to the qmp socket >>> # socat /var/run/qemu-test.qmp - >>> >>> And run the following qmp command: >>> >>> { "execute": "qmp_capabilities", "arguments": {} } >>> { "execute": "transaction", "arguments": { "actions": [{ "type": "drive-backup", "data": { "device": "drive-scsi0", "sync": "full", "target": "backup-sysi0.raw" }}, { "type": "drive-backup", "data": { "device": "drive-scsi1", "sync": "full", "target": "backup-scsi1.raw" }}], "properties": { "completion-mode": "grouped" } } } >>> >>> The VM will core dump: >>> >>> qemu: qemu_mutex_unlock_impl: Operation not permitted >>> Aborted (core dumped) >>> (gdb) bt >>> #0 0x00007f099d5037bb in __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50 >>> #1 0x00007f099d4ee535 in __GI_abort () at abort.c:79 >>> #2 0x000055c04e39525e in error_exit (err=, msg=msg@entry=0x55c04e5122e0 <__func__.16544> "qemu_mutex_unlock_impl") at util/qemu-thread-posix.c:36 >>> #3 0x000055c04e395813 in qemu_mutex_unlock_impl (mutex=mutex@entry=0x7f09903154e0, file=file@entry=0x55c04e51129f "util/async.c", line=line@entry=601) >>> at util/qemu-thread-posix.c:108 >>> #4 0x000055c04e38f8e5 in aio_context_release (ctx=ctx@entry=0x7f0990315480) at util/async.c:601 >>> #5 0x000055c04e299073 in bdrv_set_aio_context_ignore (bs=0x7f0929a76500, new_context=new_context@entry=0x7f0990315000, ignore=ignore@entry=0x7ffe08fa7400) >>> at block.c:6238 >>> #6 0x000055c04e2990cc in bdrv_set_aio_context_ignore (bs=bs@entry=0x7f092af47900, new_context=new_context@entry=0x7f0990315000, ignore=ignore@entry=0x7ffe08fa7400) >>> at block.c:6211 >>> #7 0x000055c04e299443 in bdrv_child_try_set_aio_context (bs=bs@entry=0x7f092af47900, ctx=0x7f0990315000, ignore_child=ignore_child@entry=0x0, errp=errp@entry=0x0) >>> at block.c:6324 >>> #8 0x000055c04e299576 in bdrv_try_set_aio_context (errp=0x0, ctx=, bs=0x7f092af47900) at block.c:6333 >>> #9 0x000055c04e299576 in bdrv_replace_child (child=child@entry=0x7f09902ef5e0, new_bs=new_bs@entry=0x0) at block.c:2551 >>> #10 0x000055c04e2995ff in bdrv_detach_child (child=0x7f09902ef5e0) at block.c:2666 >>> #11 0x000055c04e299ec9 in bdrv_root_unref_child (child=) at block.c:2677 >>> #12 0x000055c04e29f3fe in block_job_remove_all_bdrv (job=job@entry=0x7f0927c18800) at blockjob.c:191 >>> #13 0x000055c04e29f429 in block_job_free (job=0x7f0927c18800) at blockjob.c:88 >>> #14 0x000055c04e2a0909 in job_unref (job=0x7f0927c18800) at job.c:359 >>> #15 0x000055c04e2a0909 in job_unref (job=0x7f0927c18800) at job.c:351 >>> #16 0x000055c04e2a0b68 in job_conclude (job=0x7f0927c18800) at job.c:620 >>> #17 0x000055c04e2a0b68 in job_finalize_single (job=0x7f0927c18800) at job.c:688 >>> #18 0x000055c04e2a0b68 in job_finalize_single (job=0x7f0927c18800) at job.c:660 >>> #19 0x000055c04e2a14fc in job_txn_apply (txn=, fn=0x55c04e2a0a50 ) at job.c:145 >>> #20 0x000055c04e2a14fc in job_do_finalize (job=0x7f0927c1c200) at job.c:781 >>> #21 0x000055c04e2a1751 in job_completed_txn_success (job=0x7f0927c1c200) at job.c:831 >>> #22 0x000055c04e2a1751 in job_completed (job=0x7f0927c1c200) at job.c:844 >>> #23 0x000055c04e2a1751 in job_completed (job=0x7f0927c1c200) at job.c:835 >>> #24 0x000055c04e2a17b0 in job_exit (opaque=0x7f0927c1c200) at job.c:863 >>> #25 0x000055c04e38ee75 in aio_bh_call (bh=0x7f098ec52000) at util/async.c:164 >>> #26 0x000055c04e38ee75 in aio_bh_poll (ctx=ctx@entry=0x7f0990315000) at util/async.c:164 >>> #27 0x000055c04e3924fe in aio_dispatch (ctx=0x7f0990315000) at util/aio-posix.c:380 >>> #28 0x000055c04e38ed5e in aio_ctx_dispatch (source=, callback=, user_data=) at util/async.c:298 >>> #29 0x00007f099f020f2e in g_main_context_dispatch () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0 >>> #30 0x000055c04e391768 in glib_pollfds_poll () at util/main-loop.c:219 >>> #31 0x000055c04e391768 in os_host_main_loop_wait (timeout=) at util/main-loop.c:242 >>> #32 0x000055c04e391768 in main_loop_wait (nonblocking=nonblocking@entry=0) at util/main-loop.c:518 >>> #33 0x000055c04e032329 in qemu_main_loop () at /home/dietmar/pve5-devel/mirror_qemu/softmmu/vl.c:1665 >>> #34 0x000055c04df36a8e in main (argc=, argv=, envp=) at /home/dietmar/pve5-devel/mirror_qemu/softmmu/main.c:49 > Alright, let's start the field autopsy. What version of QEMU are you running? Sergio contributed a lot of AIO context (and iothread) fixes this release; this looks (at a glance) to be similar and related. If you are running 4.2 and not the latest HEAD, it's a strong candidate. Check this out: https://lists.gnu.org/archive/html/qemu-devel/2020-01/msg01440.html hth, --js