live migration with storage encounter assert(!(bs->open_flags & BDRV_O_INACTIVE)) crashes

The vm guest runs a iotest program, and i migrate it with virsh --copy-storage-all,then the qemu process on the source host happens to crash with the following message:

kvm: block/io.c:1543: bdrv_co_pwritev: Assertion `!(bs->open_flags & 0x0800)' failed.
2017-08-24 11:43:45.919+0000: shutting down, reason=crashed


here is the release:
qemu 2.7 & 2.10.rc3 were tested.
libvirt 3.0.0 & 3.2.0 were tested.

command line:
src_host:virsh migrate --verbose --live --persistent --copy-storage-all vm-core qemu+ssh://dst_host/system

Resaon: After bdrv_inactivate_all() was called, mirror_run coroutine stills write the left dirty disk data to remote nbd server, which triggers the assertion. But I don't known how to avoid the problem, help is needed!  Thanks.

On 08/24/2017 07:59 AM, meeho yuen wrote:
> Public bug reported:
> 
> The vm guest runs a iotest program, and i migrate it with virsh --copy-
> storage-all,then the qemu process on the source host happens to crash
> with the following message:
> 
> kvm: block/io.c:1543: bdrv_co_pwritev: Assertion `!(bs->open_flags & 0x0800)' failed.
> 2017-08-24 11:43:45.919+0000: shutting down, reason=crashed

>   here is the release:
>   qemu 2.7 & 2.10.rc3 were tested.

The just-tagged 2.10-rc4 includes a fix that should be addressing that
issue during live migration; can you please re-test with that?  (see
also https://lists.gnu.org/archive/html/qemu-devel/2017-08/msg04513.html)

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org



Thank you,I will try it.

hi,eblake,the problem still exists on qemu 2.10_rc4,although the possibility is less than before.


kvm: block/io.c:1543: bdrv_co_pwritev: Assertion `!(bs->open_flags & 0x0800)' failed.
2017-08-25 11:08:18.963+0000: shutting down, reason=crashed


I see the same thing:

2017-12-28 21:36:26.837+0000: initiating migration
qemu-system-x86_64: block/io.c:1537: bdrv_co_pwritev: Assertion `!(bs->open_flags & BDRV_O_INACTIVE)' failed.
2017-12-28 21:36:40.516+0000: shutting down, reason=crashed
~

Running:
QEMU emulator version 2.10.1
libvirtd (libvirt) 3.10.0



It seems that the following commit for libvirt fixed the problem.
https://github.com/libvirt/libvirt/blob/960326237764f8970250a3608e7b2b880e030715/src/qemu/qemu_migration.c


Looking through old bug tickets... is this still an issue with the latest version of QEMU? Or could we close this ticket nowadays?

[Expired for QEMU because there has been no activity for 60 days.]