Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754774Ab3IKXIL (ORCPT ); Wed, 11 Sep 2013 19:08:11 -0400 Received: from mail-ob0-f175.google.com ([209.85.214.175]:34833 "EHLO mail-ob0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753804Ab3IKXIK (ORCPT ); Wed, 11 Sep 2013 19:08:10 -0400 MIME-Version: 1.0 In-Reply-To: References: <52119B4E.4060409@linux.vnet.ibm.com> <20130819044444.GD26832@bbox> Date: Wed, 11 Sep 2013 18:08:08 -0500 Message-ID: Subject: Re: BUG: scheduling while atomic 3.10.7 in ZRAM Swap From: Mitch Harder To: Minchan Kim Cc: Michael wang , Linux Kernel Mailing List , Greg Kroah-Hartman , Jiang Liu , Nitin Gupta , Jerome Marchand , devel@driverdev.osuosl.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2204 Lines: 61 On Tue, Aug 20, 2013 at 9:51 AM, Mitch Harder wrote: > On Sun, Aug 18, 2013 at 11:44 PM, Minchan Kim wrote: >> Hello, >> >> On Mon, Aug 19, 2013 at 12:13:02PM +0800, Michael wang wrote: >>> Hi, Mitch >>> >>> On 08/17/2013 10:01 PM, Mitch Harder wrote: >>> > I'm encountering a BUG while using a ZRAM Swap device. >>> > >>> > The call trace seems to involve the changes recently added to 3.10.6 >>> > by the patch: >>> > zram: use zram->lock to protect zram_free_page() in swap free notify path >>> > >>> > The hardware is a x86 single CPU AMD Athlon XP system with 1GB RAM. >>> > >>> > I'm implementing a 352MB ZRAM swap device, and also have 1GB swap >>> > space on the hard disk. >>> >>> IMHO, it was caused by that swap_entry_free() was invoked with page >>> spin-locked, thus zram_slot_free_notify() should not use rw-lock which >>> may goto sleep. >>> >>> CC folks related. >> >> Thanks for Ccing me, Michael, >> >> Mitch, It's known problem and it should be fixed by [1] in recent linux-next. >> >> [1] a0c516cbfc, zram: don't grab mutex in zram_slot_free_noity >> >> Thanks for the report! >> > > Thanks. > > If I apply the zram patches from linux-next, the problem seems to be resolved. Is it planned to send the patch: "zram: don't grab mutex in zram_slot_free_noity" to stable? I noticed that 3.10.11 still doesn't have this patch. Right now, I'm manually applying 4 zram patches to my 3.10.11 kernel (although I had to rework them to apply cleanly): zram: Add auto loading of module if user opens /dev/zram. zram: prevent data loss in error cases of function zram_bvec_write() zram: fix invalid memory access zram: don't grab mutex in zram_slot_free_noity I knew I'd get errors if I didn't rework the "zram: Add auto loading of module if user opens /dev/zram" patch to apply to 3.10. The other three patches seemed to address important issues also, based on their git commit description. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/