linux-kernel - Re: [PATCHSET] timer: clean up initializers and implement irqsafe timers

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]

Message-ID: <20120813233520.GG25632@google.com>
Date:	Mon, 13 Aug 2012 16:35:20 -0700
From:	Tejun Heo <tj@...nel.org>
To:	linux-kernel@...r.kernel.org
Cc:	torvalds@...ux-foundation.org, mingo@...hat.com,
	akpm@...ux-foundation.org, tglx@...utronix.de, peterz@...radead.org
Subject: Re: [PATCHSET] timer: clean up initializers and implement irqsafe
 timers

Hello,

On Wed, Aug 08, 2012 at 11:10:24AM -0700, Tejun Heo wrote:
> Timer internals are protected by irqsafe lock but the lock is
> naturally dropped and irq enabled while a timer is executed.  This
> makes dequeueing timer for execution and the actual execution
> non-atomic against IRQs.  No matter what the timer function does, IRQs
> can occur between timer dispatch and execution.  This means that an
> IRQ handler could interrupt any timer in progress and it's impossible
> for an IRQ handler to cancel and drain a timer.

If nobody objects, I'll route this through wq/for-3.7 together with
"workqueue: use irqsafe timer in delayed_work" patchset.  If you
object, please scream.

Thanks.

-- 
tejun
--
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/