From: David Rientjes <rientjes@google.com>
To: Ming Liu <ming.liu@windriver.com>
Cc: akpm@linux-foundation.org, mhocko@suse.cz, rusty@rustcorp.com.au,
hannes@cmpxchg.org, linux-mm@kvack.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] oom: avoid killing init if it assume the oom killed thread's mm
Date: Wed, 25 Sep 2013 10:56:58 -0700 (PDT) [thread overview]
Message-ID: <alpine.DEB.2.02.1309251056020.17676@chino.kir.corp.google.com> (raw)
In-Reply-To: <52427970.8010905@windriver.com>
On Wed, 25 Sep 2013, Ming Liu wrote:
> > We shouldn't be selecting a process where mm == init_mm in the first
> > place, so this wouldn't fix the issue entirely.
>
> But if we add a control point for "mm == init_mm" in the first place(ie. in
> oom_unkillable_task), that would forbid the processes sharing mm with init to
> be selected, is that reasonable? Actually my fix is just to protect init
> process to be killed for its vfork child being selected and I think it's the
> only place where there is the risk. If my understanding is wrong, pls correct
> me.
>
We never want to select a process where task->mm == init_mm because if we
kill it we won't free any memory, regardless of vfork(). The goal of the
oom killer is solely to free memory, so it always tries to avoid needless
killing.
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2013-09-25 17:57 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-09-23 9:45 Ming Liu
2013-09-25 2:34 ` David Rientjes
2013-09-25 5:49 ` Ming Liu
2013-09-25 17:56 ` David Rientjes [this message]
2013-09-26 1:38 ` Ming Liu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=alpine.DEB.2.02.1309251056020.17676@chino.kir.corp.google.com \
--to=rientjes@google.com \
--cc=akpm@linux-foundation.org \
--cc=hannes@cmpxchg.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mhocko@suse.cz \
--cc=ming.liu@windriver.com \
--cc=rusty@rustcorp.com.au \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox