Michal Hocko wrote: > > The whole thread group is going down does not mean we make sure that > > we will send SIGKILL to other thread groups sharing the same memory which > > is possibly holding mmap_sem for write, does it? > > And the patch description doesn't say anything about processes sharing > mm. This is supposed to be a minor fix of an obviously suboptimal > behavior of task_will_free_mem. Can we stick to the proposed patch, > please? > > If we really do care about processes sharing mm _that_much_ then it > should be handled in the separate patch.
I do care. The OOM reaper cannot work unless SIGKILL is sent to a thread which is holding mmap_sem for write. Thus, sending SIGKILL to all thread groups sharing the mm is needed by your down_write_killable(&mm->mmap_sem) changes. Like I wrote at http://lkml.kernel.org/r/[email protected] , we cannot fix that problem unless you accept the slowpath. I don't like you don't explain your approach for handling the slowpath. If you explain your approach for handling the slowpath and I agree on your approach, I will also agree on the proposed patches.
