From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx5-phx2.redhat.com (mx5-phx2.redhat.com [209.132.183.37]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 66C031A000B for ; Mon, 18 Jan 2016 22:49:56 +1100 (AEDT) Date: Mon, 18 Jan 2016 06:06:22 -0500 (EST) From: Jan Stancek To: Raghavendra K T Cc: mingo@redhat.com, peterz@infradead.org, benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au, anton@samba.org, akpm@linux-foundation.org, gkurz@linux.vnet.ibm.com, grant likely , nikunj@linux.vnet.ibm.com, vdavydov@parallels.com, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Message-ID: <969916137.9009700.1453115182823.JavaMail.zimbra@redhat.com> In-Reply-To: <1452884483-11676-1-git-send-email-raghavendra.kt@linux.vnet.ibm.com> References: <1452884483-11676-1-git-send-email-raghavendra.kt@linux.vnet.ibm.com> Subject: Re: [PATCH] Fix: PowerNV crash with 4.4.0-rc8 at sched_init_numa MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , ----- Original Message ----- > From: "Raghavendra K T" > To: mingo@redhat.com, peterz@infradead.org, benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au, > anton@samba.org, akpm@linux-foundation.org > Cc: jstancek@redhat.com, gkurz@linux.vnet.ibm.com, "grant likely" , > nikunj@linux.vnet.ibm.com, vdavydov@parallels.com, "raghavendra kt" , > linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org > Sent: Friday, 15 January, 2016 8:01:23 PM > Subject: [PATCH] Fix: PowerNV crash with 4.4.0-rc8 at sched_init_numa > > Commit c118baf80256 ("arch/powerpc/mm/numa.c: do not allocate bootmem > memory for non existing nodes") avoided bootmem memory allocation for > non existent nodes. > > When DEBUG_PER_CPU_MAPS enabled, powerNV system failed to boot because > in sched_init_numa, cpumask_or operation was done on unallocated nodes. > Fix that by making cpumask_or operation only on existing nodes. > > [ Tested with and w/o DEBUG_PER_CPU_MAPS on x86 and powerpc ] > > Reported-by: Jan Stancek Tested-by: Jan Stancek I also verified with my setup, that this made the crash go away. Report mail thread for reference: https://lists.ozlabs.org/pipermail/linuxppc-dev/2016-January/137691.html Regards, Jan > Signed-off-by: Raghavendra K T > --- > kernel/sched/core.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/kernel/sched/core.c b/kernel/sched/core.c > index 44253ad..474658b 100644 > --- a/kernel/sched/core.c > +++ b/kernel/sched/core.c > @@ -6840,7 +6840,7 @@ static void sched_init_numa(void) > > sched_domains_numa_masks[i][j] = mask; > > - for (k = 0; k < nr_node_ids; k++) { > + for_each_node(k) { > if (node_distance(j, k) > sched_domains_numa_distance[i]) > continue; > > -- > 1.7.11.7 > >