Re: [Qemu-discuss] qemu-img convert stuck

[David Lee]

On Thu, Apr 12, 2018 at 10:16 AM, David Lee <address@hidden> wrote:
>> > My team caught this issue too after switching to CentOS 7.4 with qemu-img
>> > 2.9.0
>> > gdb shows exactly the same backtrace when the convert stuck, and we are on
>> > NFS.
>> >
>> > Later we found the following:
>> > 1. The stuck can happen on local storage, too.
>> > 2. Replace qemu-img 2.9.0 with 2.6.0 and everything works smoothly again.
>> >
>> > BTW, we use "qemu-img convert" to convert qcow2 and its backing files into
>> > a single qcow2 image.
>>
>> Maybe it is RHBZ 1508886?
>>
>> Fam
>
>
>
> Thanks, Fam.  We just tracked down to this BZ too and are about to trying
> the commit ef6dada8b44e1e7c4bec5c1115903af9af415b50

We tested qemu-kvm-ev-2.9.0-16.el7_4.14.1 - where from the source RPM we
verified it does contain ef6dada8b44e1e7c4bec5c1115903af9af415b50

But the issue still exists.  The convert got stuck if one of the old
active overlay
had been 'vol-resize'd  with qemu monitor command to a larger size.  This looks
like a prerequisite but not sufficient condition to trigger this badness.

-- 
Thanks,
Li Qun