Re: [PATCH -mm v2 3/3] mm/oom_kill: fix the wrong task->mm == mm checks in oom_kill_process()

From	David Rientjes <rientjes@google.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH -mm v2 3/3] mm/oom_kill: fix the wrong task->mm == mm checks in oom_kill_process()
Date	2015-09-30 23:20 +0200
Message-ID	<qewX7-8qQ-3@gated-at.bofh.it> (permalink)
References	<qeuiB-4z9-9@gated-at.bofh.it>
Organization	linux.* mail to news gateway

Show all headers | View raw

On Wed, 30 Sep 2015, Oleg Nesterov wrote:

> Both "child->mm == mm" and "p->mm != mm" checks in oom_kill_process()
> are wrong. task->mm can be NULL if the task is the exited group leader.
> This means in particular that "kill sharing same memory" loop can miss
> a process with a zombie leader which uses the same ->mm.
> 
> Note: the process_has_mm(child, p->mm) check is still not 100% correct,
> p->mm can be NULL too. This is minor, but probably deserves a fix or a
> comment anyway.
> 
> Signed-off-by: Oleg Nesterov <oleg@redhat.com>

Acked-by: David Rientjes <rientjes@google.com>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Thread

[PATCH -mm v2 3/3] mm/oom_kill: fix the wrong task->mm == mm  checks in oom_kill_process() Oleg Nesterov <oleg@redhat.com> - 2015-09-30 20:30 +0200
  Re: [PATCH -mm v2 3/3] mm/oom_kill: fix the wrong task->mm == mm  checks in oom_kill_process() David Rientjes <rientjes@google.com> - 2015-09-30 23:20 +0200
  Re: [PATCH -mm v2 3/3] mm/oom_kill: fix the wrong task->mm == mm  checks in oom_kill_process() Michal Hocko <mhocko@kernel.org> - 2015-10-01 15:00 +0200
  Re: [PATCH -mm v2 3/3] mm/oom_kill: fix the wrong task->mm == mm  checks in oom_kill_process() Andrew Morton <akpm@linux-foundation.org> - 2015-10-02 00:30 +0200

csiph-web