From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933283AbcAaSk6 (ORCPT ); Sun, 31 Jan 2016 13:40:58 -0500 Received: from mx1.redhat.com ([209.132.183.28]:57723 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933068AbcAaSk4 (ORCPT ); Sun, 31 Jan 2016 13:40:56 -0500 Date: Sun, 31 Jan 2016 19:40:48 +0100 From: Jesper Dangaard Brouer To: Stephen Rothwell Cc: Valdis.Kletnieks@vt.edu, kernel test robot , LKP , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andrew Morton , wfg@linux.intel.com, Christoph Lameter , Tejun Heo , Joonsoo Kim , brouer@redhat.com Subject: Re: [slab] a1fd55538c: WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:2601 trace_hardirqs_on_caller() Message-ID: <20160131194048.6f7add16@redhat.com> In-Reply-To: <20160131131506.4aad01b5@canb.auug.org.au> References: <56aa2b47.MwdlkrzZ08oDKqh8%fengguang.wu@intel.com> <20160128184749.7bdee246@redhat.com> <21684.1454137770@turing-police.cc.vt.edu> <20160130184646.6ea9c5f8@redhat.com> <20160131131506.4aad01b5@canb.auug.org.au> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 31 Jan 2016 13:15:06 +1100 Stephen Rothwell wrote: > Hi Jesper, > > On Sat, 30 Jan 2016 18:46:46 +0100 Jesper Dangaard Brouer wrote: > > > > Let me know, if the linux-next tree need's an explicit fix? > > It would be a good idea if you could send a fix against linux-next to > me as Andrew is currently travelling. My analysis before was wrong, the fix was much simpler. No need to revert my FAILSLAB patch. Just forgot to mask flags with gfp_allowed_mask. I expect AKPM can pickup these two small fixes to my patches. Below is a patch for linux-next. - - Best regards, Jesper Dangaard Brouer MSc.CS, Principal Kernel Engineer at Red Hat Author of http://www.iptv-analyzer.org LinkedIn: http://www.linkedin.com/in/brouer [PATCH] mm: temporary fix for SLAB in linux-next From: Jesper Dangaard Brouer This is only for linux-next, until AKPM pickup fixes two patches: base url: http://ozlabs.org/~akpm/mmots/broken-out/ [1] mm-fault-inject-take-over-bootstrap-kmem_cache-check.patch [2] slab-use-slab_pre_alloc_hook-in-slab-allocator-shared-with-slub.patch First fix is for compiling with CONFIG_FAILSLAB. The linux-next commit needing this fix is 074b6f53c320 ("mm: fault-inject take over bootstrap kmem_cache check"). Second fix is for correct masking of allowed GFP flags (gfp_allowed_mask), in SLAB allocator. This triggered a WARN, by percpu_init_late -> pcpu_mem_zalloc invoking kzalloc with GFP_KERNEL flags. The linux-next commit needing this fix is a1fd55538cae ("slab: use slab_pre_alloc_hook in SLAB allocator shared with SLUB"). Signed-off-by: Jesper Dangaard Brouer --- mm/failslab.c | 1 + mm/slab.c | 2 ++ 2 files changed, 3 insertions(+) diff --git a/mm/failslab.c b/mm/failslab.c index 0c5b3f31f310..b0fac98cd938 100644 --- a/mm/failslab.c +++ b/mm/failslab.c @@ -1,5 +1,6 @@ #include #include +#include #include "slab.h" static struct { diff --git a/mm/slab.c b/mm/slab.c index e90d259b3242..ddd974e6b3bb 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -3190,6 +3190,7 @@ slab_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid, void *ptr; int slab_node = numa_mem_id(); + flags &= gfp_allowed_mask; cachep = slab_pre_alloc_hook(cachep, flags); if (unlikely(!cachep)) return NULL; @@ -3268,6 +3269,7 @@ slab_alloc(struct kmem_cache *cachep, gfp_t flags, unsigned long caller) unsigned long save_flags; void *objp; + flags &= gfp_allowed_mask; cachep = slab_pre_alloc_hook(cachep, flags); if (unlikely(!cachep)) return NULL;