linux-kernel - Re: [PATCH 02/10] freezer: skip waking up tasks with PF_FREEZER

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:	Tue, 30 Apr 2013 19:15:01 +0200
From:	Oleg Nesterov <oleg@...hat.com>
To:	Colin Cross <ccross@...roid.com>
Cc:	linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org,
	"Rafael J. Wysocki" <rjw@...k.pl>, arve@...roid.com,
	Tejun Heo <tj@...nel.org>, Li Zefan <lizefan@...wei.com>,
	Len Brown <len.brown@...el.com>, Pavel Machek <pavel@....cz>,
	containers@...hat.com
Subject: Re: [PATCH 02/10] freezer: skip waking up tasks with
	PF_FREEZER_SKIP set

On 04/30, Oleg Nesterov wrote:
>
> On 04/29, Colin Cross wrote:
> >
> > @@ -46,10 +46,10 @@ static int try_to_freeze_tasks(bool user_only)
> >  		todo = 0;
> >  		read_lock(&tasklist_lock);
> >  		do_each_thread(g, p) {
> > -			if (p == current || !freeze_task(p))
> > +			if (p == current || freezer_should_skip(p))
> >  				continue;
> >
> > -			if (!freezer_should_skip(p))
> > +			if (freeze_task(p))
> >  				todo++;
>
> What if we race with freezer_count() ?
>
> try_to_freeze_tasks() can wrongly succeed leaving the running task
> unfrozen, no?

Ah, no, sorry for noise.

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/