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Date: Thu, 22 Dec 2016 18:31:54 +0100
From: Jan Kara <jack@suse.cz>
To: Amir Goldstein <amir73il@gmail.com>
Cc: Jan Kara <jack@suse.cz>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Lino Sanfilippo <LinoSanfilippo@gmx.de>,
        Miklos Szeredi <miklos@szeredi.hu>,
        Paul Moore <paul@paul-moore.com>
Subject: Re: [PATCH 03/22] fanotify: Move recalculation of inode / vfsmount
 mask under mark_mutex
Message-ID: <20161222173154.GA20532@quack2.suse.cz>
References: <20161222091538.28702-1-jack@suse.cz>
 <20161222091538.28702-4-jack@suse.cz>
 <CAOQ4uxj8Mp-t-yX1Yv4f4UmsLa-tfMxmmSRtCpbjOuw7w3Hnxw@mail.gmail.com>
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On Thu 22-12-16 18:27:11, Amir Goldstein wrote:
> On Thu, Dec 22, 2016 at 11:15 AM, Jan Kara <jack@suse.cz> wrote:
> > Move recalculation of inode / vfsmount notification mask under
> > group->mark_mutex of the mark which was modified. These are the only
> > places where mask recalculation happens without mark being protected
> > from detaching from inode / vfsmount which will cause issues with the
> > following patches.
> >
> 
> What am I missing this time?
> 
> dnotify_handle_event()
>    dnotify_recalc_inode_mask()
>       fsnotify_recalc_inode_mask() /* not under dnotify_group->mark_mutex */

Dnotify uses mark->lock to protect recalculation of mask which also
protects mark from being removed from the list.

								Honza
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR