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Subject: Re: [PATCH v4] mtd: Do not corrupt backing device of device node inode
From: Artem Bityutskiy <dedekind1@gmail.com>
To: "Kirill A. Shutemov" <kirill@shutemov.name>
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Date: Thu, 06 May 2010 09:39:19 +0300
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Cc: Jan Kara <jack@suse.cz>, linux-kernel@vger.kernel.org,
	David Howells <dhowells@redhat.com>,
	Alexander Shishkin <virtuoso@slind.org>, linux-mtd@lists.infradead.org,
	Alexander Viro <viro@zeniv.linux.org.uk>, linux-fsdevel@vger.kernel.org,
	David Woodhouse <dwmw2@infradead.org>, stable@kernel.org
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On Wed, 2010-05-05 at 18:40 +0300, Kirill A. Shutemov wrote:
> We cannot modify file->f_mapping->backing_dev_info, because it will corrupt
> backing device of device node inode, since file->f_mapping is equal to
> inode->i_mapping (see __dentry_open() in fs/open.c).
> 
> Let's introduce separate inode for MTD device with appropriate backing
> device.
> 
> Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
> ---
> Changelog:
>  v3 -> v4:
>   - Use igrab() instead of __iget inside the inode_lock;
>   - Add stable@ to CC list.
>  v2 -> v3:
>   - Rebase to mtd-2.6.git.
>  v1 -> v2:
>   - Fix error handling based on comments by Jan Kara.

Pushed to l2-mtd-2.6.git / dunno

Also added Jan's ack which disappeared in v4

-- 
Best Regards,
Artem Bityutskiy (Артём Битюцкий)