From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vyacheslav Dubeyko Subject: Re: New experience with the odd problem starting nilfs_cleanerd due to an eMMC misbehaviour Date: Thu, 10 Jan 2013 17:34:22 +0400 Message-ID: <1357824862.2050.48.camel@slavad-ubuntu> References: <20130110131659.GA29689@home.lan> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=dubeyko.com; s=default; h=Mime-Version:Content-Transfer-Encoding:Content-Type:References:In-Reply-To:Date:Cc:To:From:Subject:Message-ID; bh=JzrdVg09rKYHBSAW04VnkaciVVkppdZbeUB1oQRhDBU=; b=kagEGilAJufkkwRNBuGhbsk+vqlIMfGzwgkLD0XmdKZgWDG8yhJbzatqubWbc47QylNMhn45DJX11EWyf8OL7SudxShuexin1WRE7zb9Syc4CwrcFVW7xhVpkEcNnK78; In-Reply-To: <20130110131659.GA29689-0MSThuzptbI@public.gmane.org> Sender: linux-nilfs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" To: Paul Fertser Cc: linux-nilfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Hi, On Thu, 2013-01-10 at 17:16 +0400, Paul Fertser wrote: > Hi, > > I've reported this issue earlier and back then it "resolved itself" > after a power-cycle. The hardware in question is the same ac100 > netbook with an internal 32GB eMMC. > > On nilfs_cleanerd start i was consistently getting these messages: > [ 46.122096] mmcblk0: error -110 transferring data, sector 26671630, nr 10, card status 0x200900 > [ 48.934623] mmcblk0: error -110 transferring data, sector 26671631, nr 9, card status 0x200900 > (and similar output for two other sectors) > > However, this time was different, several full power cycles didn't > help and the read was still failing and cleanerd refused to start. > Could you share system log content and strace of nilfs_cleanerd's trying to start in the case of the issue? It needs for the beginning of the issue understanding. Please, set in the nilfs_cleanerd.conf debug level. Could you made raw dump of bad sectors? Could you share dumpseg output for segments which contains the bad sectors? So, I need to think how to investigate your issue without availability of eMMC. :-) Thanks, Vyacheslav Dubeyko. > So i resorted to brute force, trying to write to the sectors in > question. 512 and 2048 byte writes were failing with the same error > message, so i tried 4096 and it took about a second but succeeded: > > dd if=/dev/zero of=/dev/mmcblk0 bs=4096 count=1 seek=3333953 > > Same has to be done with the other failing sector. > > And only after that i was able to start nilfs_cleanerd and my system > seems to be running fine again. > > If it happened with e.g. ext4, i would be unable to read a certain > file and after several attempts would simply delete it and the blocks > in question would get overwritten eventually without any impact for > the system usability. However, with nilfs had i not figured out the > "dd" trick i would have to overwrite the whole filesystem (and in fact > that's the main and only partition on my netbook). The described mmc > card behaviour (i.e. remapping bad blocks only on write attempts) > seems to be kind of reasonable and i would expect the same problem to > happen with someone else one day. > > HTH -- To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html