Re: [Qemu-devel] qemu-kvm crashes doing migration with disks + blkdebug files (does not happen with qemu)

[Lucas Meneghel Rodrigues <lmr@redhat.com>]

On 11/07/2011 07:29 AM, Kevin Wolf wrote:
> Am 05.11.2011 03:16, schrieb Lucas Meneghel Rodrigues:
>> Hi folks,
>>
>> qemu-kvm is segfaulting when executing migration with blkdebug files.
>>
>> 19:50:02 DEBUG| Git repo qemu_kvm uri: git://github.com/avikivity/qemu.git
>> 19:50:02 DEBUG| Git repo qemu_kvm branch: master
>> 19:50:30 INFO | Commit hash for qemu_kvm is
>> 7879db7e9c09b92d9af1c143fbe2cc212ec89e4b (no tag found)
>>
>> How to reproduce:
>>
>> 1) create a origin vm like:
>>
>> /usr/local/autotest/tests/kvm/qemu -name 'vm1' -nodefaults -vga std
>> -monitor
>> unix:'/tmp/monitor-humanmonitor1-20111104-200902-95j0',server,nowait
>> -qmp unix:'/tmp/monitor-qmpmonitor1-20111104-200902-95j0',server,nowait
>> -serial unix:'/tmp/serial-20111104-200902-95j0',server,nowait -drive
>> file=blkdebug:/usr/local/autotest/virt/blkdebug/default.conf:/tmp/kvm_autotest_root/images/rhel6.1-64.qcow2,index=0,if=virtio,cache=none,rerror=stop,werror=stop
>> -device
>> virtio-net-pci,netdev=idtzhBVb,mac='9a:d0:7b:07:18:72',id='id9JW3ZV'
>> -netdev tap,id=idtzhBVb,fd=23 -m 2048 -smp 2 -vnc :0
>>
>>
>> 2) create a destination vm like:
>>
>> /usr/local/autotest/tests/kvm/qemu -name 'vm1' -nodefaults -vga std
>> -monitor
>> unix:'/tmp/monitor-humanmonitor1-20111104-201329-Ia9o',server,nowait
>> -qmp unix:'/tmp/monitor-qmpmonitor1-20111104-201329-Ia9o',server,nowait
>> -serial unix:'/tmp/serial-20111104-201329-Ia9o',server,nowait -drive
>> file=blkdebug:/usr/local/autotest/virt/blkdebug/default.conf:/tmp/kvm_autotest_root/images/rhel6.1-64.qcow2,index=0,if=virtio,cache=none,rerror=stop,werror=stop
>> -device
>> virtio-net-pci,netdev=idup1xAf,mac='9a:d0:7b:07:18:72',id='idyvOQf3'
>> -netdev tap,id=idup1xAf,fd=19 -m 2048 -smp 2 -vnc :1  -S -incoming
>> "exec:nc -l 5200"
>>
>> Note that blkdebug file contains:
>>
>> [inject-error]
>> state = "2"
>> event = "read_aio"
>> errno = "7"
>> immediately = "off"
>> once = "on"
>>
>> [set-state]
>> state = "1"
>> event = "read_aio"
>> new_state = "2"
>>
>> [set-state]
>> state = "2"
>> event = "read_aio"
>> new_state = "3"
>>
>> Start the migration (on this example, using exec, but it reproduces with
>> tcp and unix sockets):
>>
>> 11/04 20:13:30 DEBUG|kvm_monito:0254| (monitor humanmonitor1) Sending
>> command 'migrate -d "exec:nc localhost 5200"'
>>
>> Then you will have:
>>
>> 11/04 20:13:33 INFO |   aexpect:0783| [qemu output] invalid runstate
>> transition
>
> Invalid runstate transition is something for Luiz (CCed). Though
> probably he doesn't need to do anything in this case: I think we're not
> allowing the transition from I/O error to migrating. This might be fixed
> by 8a9236f1 in qemu.git, so please retest with upstream.

In the end of my original message, I stated the same test does not yield 
a segfault in qemu.git, so the referred commit indeed fixes the issue.

Thanks!