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Date: Thu, 28 May 2015 15:00:31 +0300
From: Cyrill Gorcunov <gorcunov@gmail.com>
To: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
        Linux Kernel <linux-kernel@vger.kernel.org>,
        Jarod Wilson <jarod@redhat.com>, Jan Stancek <jstancek@redhat.com>
Subject: Re: [PATCH 2/2] proc: fix PAGE_SIZE limit of /proc/$PID/cmdline
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On Thu, May 28, 2015 at 02:35:07PM +0300, Cyrill Gorcunov wrote:
> On Thu, May 28, 2015 at 02:14:41PM +0300, Alexey Dobriyan wrote:
> > >>
> > >> It is snapshot w.r.t getting both pairs not snapshot w.r.t atomicity or
> > >> something (unsigned long access is atomic after all). Once down_write()
> > >> is used in the other place, it even becomes obviously correct code!
> > >
> > > Not at all. It is correct if and only if you're operating under lock
> > > taken, once you fetch the pair and left the lock it simply local copies
> > > of values the descriptor had when lock was taken.
> > 
> > Yes, and?
> > 
> > You do not complain that signal statistics is collected
> > under sighand lock but printed for /proc/*/status without, do you?
> 

After thinking more, right, you're correct, sorry for noise.