Hi guys! Sometimes ago our CRIU CI started reporting hardly-reproducible (on developer environment) error "EBUSY" from fsconfig syscall in the CRIU cgroups code. https://github.com/checkpoint-restore/criu/blob/criu-dev/criu/cgroup.c#L585 The machine on which we caught this problem is PowerPC (POWER8). After tracing and debugging that we realized that problem is that we get ERESTARTNOINR from vfs_get_tree function in vfs_fsconfig_locked. After a more deep investigation, we found that the source is cgroup1_get_tree() and restart_syscall() at the end. I personally have no idea why we caught this only on POWER8 VM and have no such problem on amd64. But anyway this is incorrect behaviour and our patch should fix this problem and make this impossible on all architectures.
Big thanks to Andrei Vagin. He helped me a lot to fully understand the problem and prepare this patch. Regards, Alex Alexander Mikhalitsyn (1): fsopen: fsconfig syscall restart fix fs/fsopen.c | 32 +++++++++++++++++++++++++++++++- 1 file changed, 31 insertions(+), 1 deletion(-) -- 2.25.1
