On Mon, Oct 09, 2023 at 03:58:11PM +0200, Michal Koutný wrote: > One PID may appear multiple times in a preloaded pidlist. > (Possibly due to PID recycling but we have reports of the same > task_struct appearing with different PIDs, thus possibly involving > transfer of PID via de_thread().) > > Because v1 seq_file iterator uses PIDs as position, it leads to > a message: > > seq_file: buggy .next function kernfs_seq_next did not update position index > > Conservative and quick fix consists of removing duplicates from `tasks` > file (as opposed to removing pidlists altogether). It doesn't affect > correctness (it's sufficient to show a PID once), performance impact > would be hidden by unconditional sorting of the pidlist already in place > (asymptotically). > > Link: https://lore.kernel.org/r/20230823174804.23632-1-mkoutny@xxxxxxxx/ > Suggested-by: Firo Yang <firo.yang@xxxxxxxx> > Signed-off-by: Michal Koutný <mkoutny@xxxxxxxx> Applied to cgroup/for-6.6-fixes. Thanks. -- tejun
