From mboxrd@z Thu Jan  1 00:00:00 1970
From: Cyrill Gorcunov <gorcunov@gmail.com>
Subject: Re: [PATCH 0/5] (Was: procfs: silence lockdep warning about read vs.
 exec seq_file)
Date: Mon, 4 Aug 2014 10:59:50 +0400
Message-ID: <20140804065950.GB2239@moon>
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 <20140803164452.GA14626@redhat.com>
 <20140803211843.GA13330@redhat.com>
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Cc: "Kirill A. Shutemov" <kirill@shutemov.name>,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
	David Howells <dhowells@redhat.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Sasha Levin <levinsasha928@gmail.com>,
	"David S. Miller" <davem@davemloft.net>,
	"Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
To: Oleg Nesterov <oleg@redhat.com>
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On Sun, Aug 03, 2014 at 11:18:43PM +0200, Oleg Nesterov wrote:
> On 08/03, Oleg Nesterov wrote:
> >
> > The question is, why m_start() calls mm_access(). This is not even
> > strictly correct if the task execs between m_stop() + m_start().
> >
> > Can't we do something like below? The patch is obviously horrible and
> > incomplete, just to explain what I meant. Basically this is what
> > proc_mem_operations does.
> 
> Absolutely untested, only for review.
> 
> What do you all think?
> 
> Sure, with this change you can't open (say) /proc/pid/maps, and read the
> new mappings after exec. But hopefully this is fine? And again, this
> matches /proc/pid/mem.
> 
> lock_trace() users need another fix.

If only I didn't miss something obvious this is quite the good cleanup,
thanks Oleg!