From: Chris Ball <cjb@laptop.org>
Subject: Re: [PATCH] mke2fs: restore verbose message for BLKDISCARD
Date: Fri, 08 Mar 2013 14:08:10 -0500
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Cc: Stephen Warren <swarren@wwwdotorg.org>,
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	linux-ext4@vger.kernel.org, Stephen Warren <swarren@nvidia.com>
To: Theodore Ts'o <tytso@mit.edu>
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In-Reply-To: <20130308190019.GB12008@thunk.org> (Theodore Ts'o's message of
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Hi,

On Fri, Mar 08 2013, Theodore Ts'o wrote:
> I hate to suggest this, but there's so many crappy devices out there
> that I'm wondering if we need to figure out some way of maintaining a
> black list of devices that don't handle discard properly.

Yes, we already do that in the MMC layer.  See e.g.:

http://git.kernel.org/cgit/linux/kernel/git/cjb/mmc.git/commit/?id=3550ccdb9d8d350e526b809bf3dd92b550a74fe1
("mmc: card: Skip secure erase on MoviNAND; causes unrecoverable corruption.")

Thanks,

- Chris.
-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child