[LTP] [PATCH] cgroup_regression_test: Use unique names for hierarchies in each test

[Andrea Cervesato]

On 7/11/25 3:15 PM, Michal Koutný wrote:
> On Fri, Jul 11, 2025 at 02:41:18PM +0200, Andrea Cervesato <andrea.cervesato@suse.com> wrote:
>> This git commit is part of cgroup v1 code and now in
>> kernel/cgroup/cgroup-v1.c:cgroup1_root_to_use, but I don't see the same
>> mechanism used by cgroup v2, which is our main version.
> The patched tests use cgroup v1.
>
>> Is that something which might affect our system?
> Since there's only one cgroup v2 (unified) hierarchy, it sort of lives
> forever (statically alloc'd), so I wouldn't expect such residuals on v2
> (with the current implementation).
>
> Michal

I bisected util-linux, but it doesn't seem to be the problem. On my 
system (Tumbleweed), we are facing the same failure, no matter the 
commit that is tested in util-linux between 2.39 and 2.41 versions.

I guess this issue might be caused by a specific setup of the Linux 
kernel and its async nature, mixed with some services which are slowing 
down the umount process.

I'm wondering how to proceed, since this is actually a soft-failure and 
any fix to the test might hide future bugs.

- Andrea