linux-kernel - Re: [PATCH] hrtimer: prevent migration for raising softirq

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:	Thu, 3 Jul 2008 15:53:02 -0700
From:	Andrew Morton <akpm@...ux-foundation.org>
To:	Steven Rostedt <rostedt@...dmis.org>
Cc:	linux-kernel@...r.kernel.org, tglx@...utronix.de,
	torvalds@...ux-foundation.org, akpm@...uxfoundation.org,
	peterz@...radead.org, stable@...nel.org
Subject: Re: [PATCH] hrtimer: prevent migration for raising softirq

On Thu, 3 Jul 2008 14:31:26 -0400 (EDT)
Steven Rostedt <rostedt@...dmis.org> wrote:

> Due to a possible deadlock, the waking of the softirq was pushed outside
> of the hrtimer base locks. See commit 0c96c5979a522c3323c30a078a70120e29b5bdbc

Please quote at least the patch title rather than raw hashes.

afaict that patch isn't in 2.6.25 yet you copied stable@...nel.org. 
Please clarify.

> 
> Unfortunately this allows the task to migrate after setting up the softirq
> and raising it. Since softirqs run a queue that is per-cpu we may raise the
> softirq on the wrong CPU and this will keep the queued softirq task from
> running.
> 
> To solve this issue, this patch disables preemption around the releasing
> of the hrtimer lock and raising of the softirq.
> 

This seems to be 2.6.26 material and is inapplicable to 2.6.25?
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/