From patchwork Tue Nov 28 22:58:43 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Bringmann X-Patchwork-Id: 842356 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3ymfPs1GnCz9sDB for ; Wed, 29 Nov 2017 10:04:49 +1100 (AEDT) Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 3ymfPr6TYnzDrZ4 for ; Wed, 29 Nov 2017 10:04:48 +1100 (AEDT) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=linux.vnet.ibm.com (client-ip=148.163.158.5; helo=mx0a-001b2d01.pphosted.com; envelope-from=mwb@linux.vnet.ibm.com; receiver=) Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (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 3ymfHF5s0BzDrb3 for ; Wed, 29 Nov 2017 09:59:05 +1100 (AEDT) Received: from pps.filterd (m0098421.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id vASMrdak123651 for ; Tue, 28 Nov 2017 17:59:03 -0500 Received: from e18.ny.us.ibm.com (e18.ny.us.ibm.com [129.33.205.208]) by mx0a-001b2d01.pphosted.com with ESMTP id 2ehfhfuskc-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 28 Nov 2017 17:59:03 -0500 Received: from localhost by e18.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Tue, 28 Nov 2017 17:59:00 -0500 Received: from b01ledav003.gho.pok.ibm.com (b01ledav003.gho.pok.ibm.com [9.57.199.108]) by b01cxnp23033.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id vASMwxu252494414; Tue, 28 Nov 2017 22:58:59 GMT Received: from b01ledav003.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id F35E0B2050; Tue, 28 Nov 2017 17:56:07 -0500 (EST) Received: from oc5000245537.ibm.com (unknown [9.53.92.243]) by b01ledav003.gho.pok.ibm.com (Postfix) with ESMTP id A5F49B204E; Tue, 28 Nov 2017 17:56:07 -0500 (EST) From: Michael Bringmann To: linuxppc-dev@lists.ozlabs.org In-Reply-To: <79bd4c96-2381-c9b1-8222-b350e069655b@linux.vnet.ibm.com> Subject: [PATCH V8 3/3] hotplug/cpu: Fix crash with memoryless nodes Organization: IBM Linux Technology Center Date: Tue, 28 Nov 2017 16:58:43 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.4.0 MIME-Version: 1.0 Content-Language: en-US X-TM-AS-GCONF: 00 x-cbid: 17112822-0044-0000-0000-000003B67A2E X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00008121; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000242; SDB=6.00952622; UDB=6.00481259; IPR=6.00732703; BA=6.00005719; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00018236; XFM=3.00000015; UTC=2017-11-28 22:59:01 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17112822-0045-0000-0000-000007E5A62B Message-Id: <55ff4b6a-7f43-e171-d214-cf10d466aa71@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-11-28_12:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 impostorscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1709140000 definitions=main-1711280305 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.24 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Nathan Fontenot , Michael Bringmann Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" On powerpc systems with shared configurations of CPUs and memory and memoryless nodes at boot, an event ordering problem was observed on a SLES12 build platforms with the hot-add of CPUs to the memoryless nodes. * The most common error occurred when the memory SLAB driver attempted to reference the memoryless node to which a CPU was being added before the kernel had finished initializing all of the data structures for the CPU and exited 'device_online' under DLPAR/hot-add. Normally the memoryless node would be initialized through the call path device_online ... arch_update_cpu_topology ... find_cpu_nid ... try_online_node. This patch ensures that the powerpc node will be initialized as early as possible, even if it was memoryless and CPU-less at the point when we are trying to hot-add a new CPU to it. Signed-off-by: Michael Bringmann Reviewed-by: Nathan Fontenot --- Changes in V8: -- Change a 'printk(KERN_INFO ...)' statement to be a pr_debug() statement. -- Rename 'find_cpu_nid' to 'find_and_online_cpu_nid' for better clarity of its function. --- arch/powerpc/mm/numa.c | 4 +++- arch/powerpc/platforms/pseries/hotplug-cpu.c | 3 +++ 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c index 6b08dd8..a182f9e 100644 --- a/arch/powerpc/mm/numa.c +++ b/arch/powerpc/mm/numa.c @@ -1307,7 +1307,7 @@ static long vphn_get_associativity(unsigned long cpu, return rc; } -static inline int find_and_online_cpu_nid(int cpu) +int find_and_online_cpu_nid(int cpu) { __be32 associativity[VPHN_ASSOC_BUFSIZE] = {0}; int new_nid; @@ -1340,6 +1340,8 @@ static inline int find_and_online_cpu_nid(int cpu) #endif } + pr_debug("%s:%d cpu %d nid %d\n", __FUNCTION__, __LINE__, + cpu, new_nid); return new_nid; } diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c index a7d14aa7..dceb514 100644 --- a/arch/powerpc/platforms/pseries/hotplug-cpu.c +++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c @@ -340,6 +340,8 @@ static void pseries_remove_processor(struct device_node *np) cpu_maps_update_done(); } +extern int find_and_online_cpu_nid(int cpu); + static int dlpar_online_cpu(struct device_node *dn) { int rc = 0; @@ -364,6 +366,7 @@ static int dlpar_online_cpu(struct device_node *dn) != CPU_STATE_OFFLINE); cpu_maps_update_done(); timed_topology_update(1); + find_and_online_cpu_nid(cpu); rc = device_online(get_cpu_device(cpu)); if (rc) goto out;