From mboxrd@z Thu Jan  1 00:00:00 1970
From: Amerigo Wang <amwang@redhat.com>
Subject: Re: [Patch] pipe: use file_update_time() when hold i_mutex
Date: Wed, 22 Jul 2009 17:21:50 +0800
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Cc: Andrew Morton <akpm@linux-foundation.org>,
	linux-kernel@vger.kernel.org, heiko.carstens@de.ibm.com,
	linux-fsdevel@vger.kernel.org, viro@zeniv.linux.org.uk
To: Miklos Szeredi <mszeredi@suse.cz>
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Miklos Szeredi wrote:
> On Tue, 2009-07-21 at 18:07 +0800, Amerigo Wang wrote:
>   
>> Andrew Morton wrote:
>>     
>>> On Mon, 6 Jul 2009 01:35:30 -0400
>>> Amerigo Wang <amwang@redhat.com> wrote:
>>>
>>>   
>>>       
>>>> file_update_time() should be called with i_mutex held,
>>>> move it before mutex_unlock().
>>>>
>>>>     
>>>>         
>>> Why do you believe that file_update_time() needs i_mutex?
>>>   
>>>       
>> file_update_time() modifies inode, no? :)
>>     
>
> So does touch_atime(), yet neither needs i_mutex.
>   
Yes?

Then how the inode is protected when file_update_time() modifies
it?

Thanks.