linux-kernel - Re: [PATCH] prinkt/nbcon: Add a scheduling point to nbcon_kthread

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Fri, 21 Jun 2024 03:22:49 +0206
From: John Ogness <john.ogness@...utronix.de>
To: Sebastian Andrzej Siewior <bigeasy@...utronix.de>, Derek Barbosa
 <debarbos@...hat.com>
Cc: pmladek@...e.com, rostedt@...dmis.org, senozhatsky@...omium.org,
 linux-rt-users@...r.kernel.org, linux-kernel@...r.kernel.org,
 williams@...hat.com, jlelli@...hat.com, ahalaney@...hat.com,
 lgoncalv@...hat.com, jwyatt@...hat.com, aubaker@...hat.com
Subject: Re: [PATCH] prinkt/nbcon: Add a scheduling point to
 nbcon_kthread_func().

On 2024-06-20, Sebastian Andrzej Siewior <bigeasy@...utronix.de> wrote:
> Constant printing can lead to a CPU hog in nbcon_kthread_func(). The
> context is preemptible but on !PREEMPT kernels there is no explicit
> preemption point which leads softlockup warnings.
>
> Add an explicit preemption point in nbcon_kthread_func().
>
> Reported-by: Derek Barbosa <debarbos@...hat.com>
> Link: https://lore.kernel.org/ZnHF5j1DUDjN1kkq@debarbos-thinkpadt14sgen2i.remote.csb
> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@...utronix.de>

Reviewed-by: John Ogness <john.ogness@...utronix.de>