From: Stephen Warren Subject: Re: [PATCH] mke2fs: restore verbose message for BLKDISCARD Date: Fri, 08 Mar 2013 13:03:41 -0700 Message-ID: <513A441D.1060706@wwwdotorg.org> References: <1362515118-30344-1-git-send-email-swarren@wwwdotorg.org> <5138EEBD.5000705@wwwdotorg.org> <513A1D56.1010402@wwwdotorg.org> <20130308190019.GB12008@thunk.org> <87vc91zp45.fsf@octavius.laptop.org> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: Theodore Ts'o , =?windows-1252?Q?Luk=E1=9A_Czerner?= , linux-ext4@vger.kernel.org, Stephen Warren To: Chris Ball Return-path: Received: from avon.wwwdotorg.org ([70.85.31.133]:50223 "EHLO avon.wwwdotorg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753281Ab3CHUDp (ORCPT ); Fri, 8 Mar 2013 15:03:45 -0500 In-Reply-To: <87vc91zp45.fsf@octavius.laptop.org> Sender: linux-ext4-owner@vger.kernel.org List-ID: On 03/08/2013 12:08 PM, Chris Ball wrote: > 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.") Unrecoverable sounds scary. Does that just mean data corruption, or a permanently broken device? mk2e2fs -K followed by e2fsck and mounting luckily seems to still work OK for me:-) FWIW, my CID is 45010053454d31364790711c665f3e00, i.e. manufacturer ID 0x45, device name SEM16G.