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Date: Fri, 15 Apr 2016 01:50:38 +0100
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Andrey Ulanov <andreyu@google.com>
Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] namespace: update event counter when umounting a deleted
 dentry
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On Thu, Apr 14, 2016 at 04:48:32PM -0700, Andrey Ulanov wrote:
> +++ b/fs/namespace.c
> @@ -1562,6 +1562,7 @@ void __detach_mounts(struct dentry *dentry)
>  		goto out_unlock;
>  
>  	lock_mount_hash();
> +	event++;

That part makes sense.

> -/* 
> +/*
>   * Is the caller allowed to modify his namespace?
>   */
>  static inline bool may_mount(void)
> @@ -1765,6 +1766,7 @@ void drop_collected_mounts(struct vfsmount *mnt)
>  {
>  	namespace_lock();
>  	lock_mount_hash();
> +	event++;

... but what the hell is this one for?