From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx119.postini.com [74.125.245.119]) by kanga.kvack.org (Postfix) with SMTP id BFF786B0044 for ; Thu, 8 Nov 2012 01:35:24 -0500 (EST) Message-ID: <509B533B.7090907@redhat.com> Date: Thu, 08 Nov 2012 14:37:47 +0800 From: Zhouping Liu MIME-Version: 1.0 Subject: Re: [RFC PATCH 00/19] Foundation for automatic NUMA balancing References: <1352193295-26815-1-git-send-email-mgorman@suse.de> <509A2970.9000408@redhat.com> <20121107152558.GZ8218@suse.de> In-Reply-To: <20121107152558.GZ8218@suse.de> Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Mel Gorman Cc: Peter Zijlstra , Andrea Arcangeli , Ingo Molnar , Rik van Riel , Johannes Weiner , Hugh Dickins , Thomas Gleixner , Linus Torvalds , Andrew Morton , Linux-MM , LKML , CAI Qian On 11/07/2012 11:25 PM, Mel Gorman wrote: > On Wed, Nov 07, 2012 at 05:27:12PM +0800, Zhouping Liu wrote: >> Hello Mel, >> >> my 2 nodes machine hit a panic fault after applied the patch >> set(based on kernel-3.7.0-rc4), please review it: >> >> > Early initialisation problem by the looks of things. Try this please Tested the patch, and the issue is gone. > > ---8<--- > mm: numa: Check that preferred_node_policy is initialised > > Zhouping Liu reported the following > > [ 0.000000] ------------[ cut here ]------------ > [ 0.000000] kernel BUG at mm/mempolicy.c:1785! > [ 0.000000] invalid opcode: 0000 [#1] SMP > [ 0.000000] Modules linked in: > [ 0.000000] CPU 0 > .... > [ 0.000000] Call Trace: > [ 0.000000] [] alloc_pages_current+0xa6/0x170 > [ 0.000000] [] __get_free_pages+0x14/0x50 > [ 0.000000] [] kmem_cache_init+0x53/0x2d2 > [ 0.000000] [] start_kernel+0x1e0/0x3c7 > > Problem is that early in boot preferred_nod_policy and SLUB > initialisation trips up. Check it is initialised. > > Signed-off-by: Mel Gorman Tested-by: Zhouping Liu Thanks, Zhouping > --- > mm/mempolicy.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/mm/mempolicy.c b/mm/mempolicy.c > index 11d4b6b..8cfa6dc 100644 > --- a/mm/mempolicy.c > +++ b/mm/mempolicy.c > @@ -129,6 +129,10 @@ static struct mempolicy *get_task_policy(struct task_struct *p) > node = numa_node_id(); > if (node != -1) > pol = &preferred_node_policy[node]; > + > + /* preferred_node_policy is not initialised early in boot */ > + if (!pol->mode) > + pol = NULL; > } > > return pol; > > -- > 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 -- 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