On Mon 13-06-16 13:23:48, Michal Hocko wrote: > On Thu 09-06-16 13:52:07, Michal Hocko wrote: > > I would like to explore ways how to remove kthreads (use_mm) special > > case. It shouldn't be that hard, we just have to teach the page fault > > handler to recognize oom victim mm and enforce EFAULT for kthreads > > which have borrowed that mm. > > So I was trying to come up with solution for this which would require to > hook into the pagefault an enforce EFAULT when the mm is being reaped > by the oom_repaer. Not hard but then I have checked the current users > and none of them is really needing to read from the userspace (aka > copy_from_user/get_user). So we actually do not need to do anything > special.
As pointed out by Tetsuo [1] vhost does realy on copy_from_user. I just missed that. So scratch this. I will revisit a potential solution for this but that would be outside of this series scope. [1] http://lkml.kernel.org/r/201606132252.iae00593.ojqsfmtvfol...@i-love.sakura.ne.jp -- Michal Hocko SUSE Labs