>>> Breaking this circle was not that easy with pid namespaces, so >>> I put the strut in proc_flush_task - when the last task from the >>> namespace exits the kern-mount-ed vfsmnt is dropped, but we can't >>> do the same stuff with devpts. >> But I still don't see what the problem is with my proposal? So long as >> you agree that if there are no tasks remaining in the devptsns, >> then any task which has its devpts mounted should see an empty directory >> (due to sb->s_info being NULL), I think it works. > > Well, if we _do_ can handle the races with ns->devpts_mnt switch > from not NULL to NULL, then I'm fine with this approach. I 'll take a look at it for the mq namespace. we will need to flush the dcache in some way nop ? to make sure the lookup in the directory fails to return anything after the ns has become NULL. I'm not an fs expert so I might be completely wrong there but I'll study in this direction to see if we can drop the CLONE_NEWNS. > I just remember, that with pid namespaces this caused a complicated > locking and performance degradation. This is the problem I couldn't > remember yesterday. That might have been bc you had to invalidate the /proc dentries ? C. _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers
