From: Quentin Perret <qperret@google.com>
To: Valentin Schneider <valentin.schneider@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>,
Kirill Tkhai <ktkhai@virtuozzo.com>,
linux-kernel@vger.kernel.org, aaron.lwe@gmail.com,
mingo@kernel.org, pauld@redhat.com, jdesfossez@digitalocean.com,
naravamudan@digitalocean.com, vincent.guittot@linaro.org,
dietmar.eggemann@arm.com, juri.lelli@redhat.com,
rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de,
kernel-team@android.com, john.stultz@linaro.org
Subject: Re: NULL pointer dereference in pick_next_task_fair
Date: Fri, 8 Nov 2019 11:58:10 +0000 [thread overview]
Message-ID: <20191108115810.GA83597@google.com> (raw)
In-Reply-To: <07d30588-22e6-e098-b591-29c7cd3c8054@arm.com>
On Friday 08 Nov 2019 at 11:47:44 (+0000), Valentin Schneider wrote:
> I think we can ignore RETRY_TASK because this happens before the picking loop,
> so we'll observe any new DL/RT task that got enqueued while newidle released
> the lock. This also means we can safely break the balance loop in
> pick_next_task() when we get RETRY_TASK, because we've got something to pick
> (some new RT/DL task).
Ah right, the second loop always iterates from DL, so that works.
> This wants a comment though, methinks.
+1 :)
Thanks,
Quentin
next prev parent reply other threads:[~2019-11-08 11:58 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-28 17:46 NULL pointer dereference in pick_next_task_fair Quentin Perret
2019-10-28 21:49 ` Peter Zijlstra
2019-10-29 11:34 ` Peter Zijlstra
2019-10-29 11:50 ` Quentin Perret
2019-10-30 22:50 ` Ram Muthiah
2019-10-31 1:33 ` Valentin Schneider
2019-10-31 10:54 ` Valentin Schneider
2019-10-31 14:24 ` Valentin Schneider
2019-10-31 22:15 ` Valentin Schneider
2019-11-06 12:05 ` Peter Zijlstra
2019-11-06 13:08 ` Peter Zijlstra
2019-11-06 15:04 ` Qais Yousef
2019-11-06 16:57 ` Peter Zijlstra
2019-11-06 17:26 ` Qais Yousef
2019-11-06 15:51 ` Kirill Tkhai
2019-11-06 16:54 ` Peter Zijlstra
2019-11-06 17:27 ` Peter Zijlstra
2019-11-07 8:36 ` Kirill Tkhai
2019-11-07 13:26 ` Peter Zijlstra
2019-11-07 15:12 ` Kirill Tkhai
2019-11-07 15:42 ` Peter Zijlstra
2019-11-07 15:53 ` Kirill Tkhai
2019-11-07 15:38 ` Quentin Perret
2019-11-07 18:43 ` Peter Zijlstra
2019-11-07 19:27 ` Quentin Perret
2019-11-07 19:31 ` Peter Zijlstra
2019-11-07 19:42 ` Quentin Perret
2019-11-07 19:29 ` Peter Zijlstra
2019-11-08 11:02 ` Quentin Perret
2019-11-08 11:47 ` Valentin Schneider
2019-11-08 11:58 ` Quentin Perret [this message]
2019-11-08 12:00 ` Peter Zijlstra
2019-11-08 12:15 ` Quentin Perret
2019-11-08 12:35 ` Peter Zijlstra
2019-11-08 12:24 ` Peter Zijlstra
2019-11-08 11:55 ` Peter Zijlstra
2019-11-08 12:52 ` Peter Zijlstra
2019-11-07 16:09 ` Qais Yousef
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=20191108115810.GA83597@google.com \
--to=qperret@google.com \
--cc=aaron.lwe@gmail.com \
--cc=bsegall@google.com \
--cc=dietmar.eggemann@arm.com \
--cc=jdesfossez@digitalocean.com \
--cc=john.stultz@linaro.org \
--cc=juri.lelli@redhat.com \
--cc=kernel-team@android.com \
--cc=ktkhai@virtuozzo.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mgorman@suse.de \
--cc=mingo@kernel.org \
--cc=naravamudan@digitalocean.com \
--cc=pauld@redhat.com \
--cc=peterz@infradead.org \
--cc=rostedt@goodmis.org \
--cc=valentin.schneider@arm.com \
--cc=vincent.guittot@linaro.org \
/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;
as well as URLs for NNTP newsgroup(s).