From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: proc:Add a reference of module when proc_reg_file opened
Date: Sun, 26 Feb 2012 07:50:25 +0000
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To: majianpeng <majianpeng@gmail.com>
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On Sun, Feb 26, 2012 at 02:34:48PM +0800, majianpeng wrote:
> >From 49b46362bf3221a259bfc73105ad041376b66878 Mon Sep 17 00:00:00 2001
> From: majianpeng <majianpeng@gmail.com>
> Date: Sun, 26 Feb 2012 22:19:51 +0800
> Subject: [PATCH] proc:Add a reference of module when proc_reg_file opened.
> 
> If struct file_operations of a regular file in procfs defined in module
> and defined .owner = THIS_MODULE,open this file must get a reference of
> module.

No.  Read remove_proc_entry(), especially the part under ->pde_unload_lock.
The whole damn point of that stuff is that opened file on procfs does *not*
pin the module down; IO in progress does, but that's it.

You can't deadlock rmmod foobar </proc/crap/foobar; with your patch we'll
be back to a pile of deadlocks in there.

IOW, NAK.