linux-kernel - Re: [PATCH 4/7] cgroup_freezer: don't stall transition to FROZEN for PF_NOFREEZE or 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]

Message-ID: <20121022183453.GA24687@redhat.com>
Date:	Mon, 22 Oct 2012 20:34:53 +0200
From:	Oleg Nesterov <oleg@...hat.com>
To:	Tejun Heo <tj@...nel.org>
Cc:	rjw@...k.pl, linux-kernel@...r.kernel.org, lizefan@...wei.com,
	containers@...ts.linux-foundation.org, cgroups@...r.kernel.org
Subject: Re: [PATCH 4/7] cgroup_freezer: don't stall transition to FROZEN
	for PF_NOFREEZE or PF_FREEZER_SKIP tasks

On 10/16, Tejun Heo wrote:
>
> cgroup_freezer doesn't transition from FREEZING to FROZEN if the
> cgroup contains PF_NOFREEZE tasks or tasks sleeping with
> PF_FREEZER_SKIP set.

And thus the patch looks like another bugfix to me.


Just one question, and this question is offtopic again,

> Only kernel tasks can be non-freezable (PF_NOFREEZE)

Hmm. We seem to "leak" PF_NOFREEZE if a kernel thread execs?
Perhaps do_execve_common() should do set_freezable() before return.

Or, at least, simply clear this flag along with PF_KTHREAD in
flush_old_exec().

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/