On 21/8/2019 5:14 PM, Lukáš Doktor wrote: > Hello guys, > > First attempt was rejected due to zip attachment, let's try it again with > just Avocado-vt debug.log and serial console log files attached. > > I bisected a regression on aarch64 all the way to this commit: "qcow2: skip > writing zero buffers to empty COW areas" > c8bb23cbdbe32f5c326365e0a82e1b0e68cdcd8a. Would you please have a look at it? > > My reproducer is running kickstart installation of RHEL-8 from DVD on aarch64 > gicv3 machine, which never finishes since this commit, where anaconda > complains about package installation, occasionally there are also XFS > metadata corruption messages on serial console: >
hi, this looks scary :( I doubt that it can have anything to do with aarch64 but rather a really tricky timing (or, possibly, a broken environment like broken fallocate() on a host? who knows..) Is it always the same machine you observe this issue on? Did you try others? I just wonder if it's worth to try to reproduce it on my machine (and I don't have aarch64 on hand now). I can probably come up with some torture test that will continuously write to qcow2 with random offsets/sizes and verify the result. If you could kindly reproduce it again then we can probably start with enabling qemu traces by appending " -trace bdrv* -trace qcow2* -trace file=/some_huge_partition/qemu.log" to the command line. Beware that it's going to produce a huge amount of logs. Also, the corrupted image and the serial log will be required for investigation. thanks, /Anton
