From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?B?UGF2ZWwgUGFsw6F0?= Subject: bcache writeback hang with 3.11.5 and 3.10.17 Date: Sun, 20 Oct 2013 15:42:33 +0200 Message-ID: <5263DDC9.6050705@devsoft.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: Sender: linux-bcache-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: linux-bcache-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-bcache@vger.kernel.org Hello, I have experienced hangs with above kernel and bcache in writeback mode. Hangs are very easily archieved - just do: mkdir /data/tmp cp -xar / /data/tmp Cancel after 1-5 minutes, then do sync (sometimes don't needed) and it hangs. Either the sync hangs and/or the cp (or rm /data/tmp). Behaviour is very consistent, it happens every time I enable writeback and perform IO heavy operations. I have not experienced the issue so far with writethrough mode. Hardware is HP j000ec, attaching dmesg from hanged box with both 3.11.5 and 3.10.17 LTS kernel. Distribution is arch linux. dmesg outputs is available on http://www.devsoft.cz/upload/bcache_bugreport.tar.gz P.