Hi everyone,

(CCs just based on tags in the commit in question)

I have two bug reports which claim problems of qcow2 on XFS on ppc64le
machines since qemu 4.1.0.  One of those is about bad performance
(sorry, is isn’t public :-/), the other about data corruption
(https://bugzilla.redhat.com/show_bug.cgi?id=1751934).

It looks like in both cases reverting c8bb23cbdbe3 solves the problem
(which optimized COW of unallocated areas).

I think I’ve looked at every angle but can‘t find what could be wrong
with it.  Do any of you have any idea? :-/


Thanks,

Max