From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail137.messagelabs.com (mail137.messagelabs.com [216.82.249.19]) by kanga.kvack.org (Postfix) with SMTP id 74ED76B005C for ; Fri, 15 May 2009 11:21:34 -0400 (EDT) Received: by yx-out-1718.google.com with SMTP id 36so988540yxh.26 for ; Fri, 15 May 2009 08:21:42 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <1242374931.21646.30.camel@penberg-laptop> References: <1242289830.21646.5.camel@penberg-laptop> <20090514175332.9B7B.A69D9226@jp.fujitsu.com> <20090515083726.F5BF.A69D9226@jp.fujitsu.com> <1242374931.21646.30.camel@penberg-laptop> Date: Sat, 16 May 2009 00:21:42 +0900 Message-ID: <2f11576a0905150821m5c602ef7g996766ae5d7f0141@mail.gmail.com> Subject: Re: kernel BUG at mm/slqb.c:1411! From: KOSAKI Motohiro Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Sender: owner-linux-mm@kvack.org To: Pekka Enberg Cc: Minchan Kim , linux-mm , LKML , Nick Piggin , matthew.r.wilcox@intel.com List-ID: 2009/5/15 Pekka Enberg : > Hi Motohiro-san, > > On Wed, 2009-05-13 at 17:37 +0900, Minchan Kim wrote: >> > > > On Wed, 13 May 2009 16:42:37 +0900 (JST) >> > > > KOSAKI Motohiro wrote: >> > > > >> > > > Hmm. I don't know slqb well. >> > > > So, It's just my guess. >> > > > >> > > > We surely increase l->nr_partial in =A0__slab_alloc_page. >> > > > In between l->nr_partial++ and call __cache_list_get_page, Who is = decrease l->nr_partial again. >> > > > After all, __cache_list_get_page return NULL and hit the VM_BUG_ON= . >> > > > >> > > > Comment said : >> > > > >> > > > =A0 =A0 =A0 =A0 /* Protects nr_partial, nr_slabs, and partial */ >> > > > =A0 spinlock_t =A0 =A0page_lock; >> > > > >> > > > As comment is right, We have to hold the l->page_lock ? >> > > >> > > Makes sense. Nick? Motohiro-san, can you try this patch please? >> > >> > This issue is very rarely. please give me one night. > > On Fri, 2009-05-15 at 08:38 +0900, KOSAKI Motohiro wrote: >> -ENOTREPRODUCED >> >> I guess your patch is right fix. thanks! > > Thank you so much for testing! > > Nick seems to have gone silent for the past few days so I went ahead and > merged the patch. > > Did you have CONFIG_PROVE_LOCKING enabled, btw? I think I got the lock > order correct but I don't have a NUMA machine to test it with here. my x86_64 with CONFIG_PROVE_LOCKING don't output any warnings. thanks. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org