From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sitsofe Wheeler Subject: Re: Issue (as expected) when upgrading from 3.12 to 3.13.7 Date: Sun, 30 Mar 2014 12:47:55 +0100 Message-ID: <20140330114747.GA15353@sucs.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from silver.sucs.swan.ac.uk ([137.44.10.1]:34415 "EHLO silver.sucs.swan.ac.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752725AbaC3Lr5 (ORCPT ); Sun, 30 Mar 2014 07:47:57 -0400 Content-Disposition: inline In-Reply-To: Sender: linux-bcache-owner@vger.kernel.org List-Id: linux-bcache@vger.kernel.org To: Kent Overstreet Cc: Francis Moreau , linux-bcache@vger.kernel.org Hi, On Sun, Mar 30, 2014 at 12:53:12PM +0200, Francis Moreau wrote: > > As I was expecting I'm getting new issues with bcache after upgrading my > kernel: > > [Mar30 12:24] INFO: task bcache_writebac:155 blocked for more than 120 > seconds. > [ +0.000007] Not tainted 3.13.7-1-ARCH #1 > [ +0.000002] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" > disables this message. > [ +0.000003] bcache_writebac D 0000000000000000 0 155 2 > 0x00000000 > [ +0.000006] ffff8804049c5eb8 0000000000000046 ffff880405816c00 > ffff8804049c5fd8 > [ +0.000005] 0000000000014440 0000000000014440 ffff880405816c00 > ffff8804049c5e38 > [ +0.000004] ffffffff810925fa 24448b48e0d83524 fa83ffffee31e918 > 0000000000000046 > [ +0.000004] Call Trace: > [ +0.000010] [] ? try_to_wake_up+0x1fa/0x2c0 > [ +0.000006] [] ? default_wake_function+0x12/0x20 > [ +0.000005] [] ? __wake_up_common+0x58/0x90 > [ +0.000023] [] ? read_dirty_endio+0x60/0x60 [bcache] > [ +0.000005] [] schedule+0x29/0x70 > [ +0.000006] [] kthread+0xad/0xf0 > [ +0.000005] [] ? kthread_create_on_node+0x180/0x180 > [ +0.000005] [] ret_from_fork+0x7c/0xb0 > [ +0.000005] [] ? kthread_create_on_node+0x180/0x180 > > That's just sad to see how unstable was/is bcache sub system and I still > don't understand why it was not marked as experimental. > > 3.12 was/is buggy when used with writeback mode, and I just had to live > with cache-through. I tried to get some helps (and others too) but no > answers. > > I read there were issue with 3.13, so I delayed my kernel upgrade as far > I could due to this. I was hoping that issues were fixed in 3.13.x > stable tree but apparently not. > > Hopefully this one will not be ignored. Francis - I've found it helps if you add all the relevant addresses mentioned in https://www.kernel.org/doc/linux/MAINTAINERS . For this mail I'm going to explicitly CC Kent to help this get noticed. Additionally do you also see this problem with 3.14? -- Sitsofe | http://sucs.org/~sits/