From: Yury Norov <yury.norov@gmail.com>
To: Christian Loehle <christian.loehle@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>,
Dietmar Eggemann <dietmar.eggemann@arm.com>,
Mark Rutland <Mark.Rutland@arm.com>,
Thomas Gleixner <tglx@linutronix.de>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Juri Lelli <juri.lelli@redhat.com>,
Valentin Schneider <vschneid@redhat.com>
Subject: Re: PATCH] sched: Fix sched_numa_find_nth_cpu() if mask offline
Date: Wed, 3 Sep 2025 12:15:17 -0400 [thread overview]
Message-ID: <aLhplQVvIJqWo1ac@yury> (raw)
In-Reply-To: <1ae868cf-470b-44d8-bda3-20a64dedd8b8@arm.com>
On Wed, Sep 03, 2025 at 04:48:32PM +0100, Christian Loehle wrote:
> sched_numa_find_nth_cpu() uses a bsearch to look for the 'closest'
> CPU in sched_domains_numa_masks and given cpus mask. However they
> might not intersect if all CPUs in the cpus mask are offline. bsearch
> will return NULL in that case, bail out instead of dereferencing a
> bogus pointer.
>
> The previous behaviour lead to this bug when using maxcpus=4 on an
> rk3399 (LLLLbb) (i.e. booting with all big CPUs offline):
Thanks! Scheduling for -rc5.
prev parent reply other threads:[~2025-09-03 16:15 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-09-03 15:48 PATCH] sched: Fix sched_numa_find_nth_cpu() if mask offline Christian Loehle
2025-09-03 16:15 ` Yury Norov [this message]
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=aLhplQVvIJqWo1ac@yury \
--to=yury.norov@gmail.com \
--cc=Mark.Rutland@arm.com \
--cc=christian.loehle@arm.com \
--cc=dietmar.eggemann@arm.com \
--cc=juri.lelli@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=peterz@infradead.org \
--cc=tglx@linutronix.de \
--cc=vschneid@redhat.com \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.