linux-kernel - Re: [PATCH 2/2] sched: Move task_mm_cid

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] [day] [month] [year] [list]

Message-ID: <81cc8be1b5fe76a3323c2990994442f7e7959629.camel@redhat.com>
Date: Wed, 04 Dec 2024 09:01:36 +0100
From: Gabriele Monaco <gmonaco@...hat.com>
To: Joel Fernandes <joel@...lfernandes.org>, Mathieu Desnoyers
	 <mathieu.desnoyers@...icios.com>
Cc: Ingo Molnar <mingo@...hat.com>, Peter Zijlstra <peterz@...radead.org>, 
 Juri Lelli <juri.lelli@...hat.com>, Vincent Guittot
 <vincent.guittot@...aro.org>, Dietmar Eggemann	 <dietmar.eggemann@....com>,
 Steven Rostedt <rostedt@...dmis.org>, Ben Segall	 <bsegall@...gle.com>, Mel
 Gorman <mgorman@...e.de>, Valentin Schneider	 <vschneid@...hat.com>,
 linux-kernel@...r.kernel.org, paulmck <paulmck@...nel.org>,  Frederic
 Weisbecker	 <frederic@...nel.org>, Neeraj Upadhyay
 <neeraj.upadhyay@...nel.org>, Josh Triplett <josh@...htriplett.org>, Boqun
 Feng <boqun.feng@...il.com>, Uladzislau Rezki	 <urezki@...il.com>, Lai
 Jiangshan <jiangshanlai@...il.com>, Zqiang	 <qiang.zhang1211@...il.com>,
 "rcu@...r.kernel.org" <rcu@...r.kernel.org>
Subject: Re: [PATCH 2/2] sched: Move task_mm_cid_work to RCU callback


On Tue, 2024-12-03 at 10:00 -0500, Joel Fernandes wrote:
> 
> Also there is no guarantee that RCU callback will run within a thread
> context (example, some configurations run it in softirq). Further,
> call_rcu() usage as shown in this patch can also delay callback runs
> by seconds (with RCU_LAZY enabled).
> 
> See also #5 in checklist: https://docs.kernel.org/RCU/checklist.html
> 

Thanks for the tips, I get the RCU callbacks are clearly not the right
place where to put this function.
I'm working on a V2 where the same tick is scheduling a new work_struct
in the mm_struct instead, let's see where that brings.

Thanks all for the constructive comments.
Gabriele