linux-kernel - Re: 2.6.22-rc1: Broken suspend on SMP with tifm

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:	Mon, 14 May 2007 01:54:25 +0400
From:	Oleg Nesterov <oleg@...sign.ru>
To:	"Rafael J. Wysocki" <rjw@...k.pl>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	LKML <linux-kernel@...r.kernel.org>,
	Michal Piotrowski <michal.k.k.piotrowski@...il.com>,
	Alex Dubov <oakad@...oo.com>, Pierre Ossman <drzeus@...eus.cx>
Subject: Re: 2.6.22-rc1: Broken suspend on SMP with tifm

On 05/13, Rafael J. Wysocki wrote:
>
> On Sunday, 13 May 2007 23:34, Oleg Nesterov wrote:
> > On 05/13, Rafael J. Wysocki wrote:
> > >
> > > @@ -819,20 +843,31 @@ static int __devinit workqueue_cpu_callb
> > >  
> > > +
> > > +		case CPU_DEAD_FROZEN:
> > > +			if (wq->freezeable) {
> > > +				take_over_work(wq, cpu);
> > > +				thaw_process(cwq->thread);
> > 
> > Suppose that PF_NOFREEZE task T does flush_workqueue(), and CPU 1 has pending
> > works. T does flush_cpu_workqueue(0), CPU_DEAD_FROZEN moves works from CPU 1
> > to CPU 0, T does flush_cpu_workqueue(1) and finds nothing.
> 
> I don't think this is possible, because we've acquired workqueue_mutex in
> _cpu_down().

Yes, we did... but flush_workqueue() doesn't take it?

Oleg.

-
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/