Date: Mon, 4 Mar 2013 21:53:07 +0100
From: Oleg Nesterov <oleg@redhat.com>
To: Mandeep Singh Baines <msb@chromium.org>
Cc: Jeff Layton <jlayton@redhat.com>,
        "Myklebust, Trond" <Trond.Myklebust@netapp.com>,
        Ming Lei <ming.lei@canonical.com>,
        "J. Bruce Fields" <bfields@fieldses.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        "linux-nfs@vger.kernel.org" <linux-nfs@vger.kernel.org>,
        "Rafael J. Wysocki" <rjw@sisk.pl>,
        Andrew Morton <akpm@linux-foundation.org>, Tejun Heo <tj@kernel.org>,
        Ingo Molnar <mingo@redhat.com>
Subject: Re: LOCKDEP: 3.9-rc1: mount.nfs/4272 still has locks held!
Message-ID: <20130304205307.GA13527@redhat.com>
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On 03/04, Mandeep Singh Baines wrote:
>
> The problem is that freezer_count() calls try_to_freeze(). In this
> case, try_to_freeze() is not really adding any value.

Well, I tend to agree.

If a task calls __refrigerator() holding a lock which another freezable
task can wait for, this is not freezer-friendly.

freezable_schedule/freezer_do_not_count/etc not only means "I won't be
active if freezing()", it should also mean "I won't block suspend/etc".

OTOH, I understand that probably it is not trivial to change this code
to make it freezer-friendly. But at least  I disagree with "push your
problems onto others".

Oleg.