From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5DCB5C3A5A6 for ; Tue, 27 Aug 2019 10:19:00 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id CC9E420656 for ; Tue, 27 Aug 2019 10:18:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CC9E420656 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.vnet.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 46HlG92pmGzDqT7 for ; Tue, 27 Aug 2019 20:18:57 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=none (mailfrom) smtp.mailfrom=linux.vnet.ibm.com (client-ip=148.163.156.1; helo=mx0a-001b2d01.pphosted.com; envelope-from=maddy@linux.vnet.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.vnet.ibm.com Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (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 46HlCw2Sz9zDqVR for ; Tue, 27 Aug 2019 20:16:56 +1000 (AEST) Received: from pps.filterd (m0098409.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x7RAGox0143198 for ; Tue, 27 Aug 2019 06:16:51 -0400 Received: from e06smtp03.uk.ibm.com (e06smtp03.uk.ibm.com [195.75.94.99]) by mx0a-001b2d01.pphosted.com with ESMTP id 2un0nvcxpk-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Tue, 27 Aug 2019 06:16:51 -0400 Received: from localhost by e06smtp03.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Tue, 27 Aug 2019 11:16:47 +0100 Received: from d06av23.portsmouth.uk.ibm.com (d06av23.portsmouth.uk.ibm.com [9.149.105.59]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x7RAGkjO56688716 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 27 Aug 2019 10:16:46 GMT Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id EF2F6A4059; Tue, 27 Aug 2019 10:16:45 +0000 (GMT) Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id B669FA4053; Tue, 27 Aug 2019 10:16:44 +0000 (GMT) Received: from localhost.localdomain.com (unknown [9.199.54.184]) by d06av23.portsmouth.uk.ibm.com (Postfix) with ESMTP; Tue, 27 Aug 2019 10:16:44 +0000 (GMT) From: Madhavan Srinivasan To: mpe@ellerman.id.au Subject: [PATCH v3] powerpc/imc: Dont create debugfs files for cpu-less nodes Date: Tue, 27 Aug 2019 15:46:35 +0530 X-Mailer: git-send-email 2.21.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 x-cbid: 19082710-0012-0000-0000-000003436EDA X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19082710-0013-0000-0000-0000217DA6C6 Message-Id: <20190827101635.6942-1-maddy@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-08-27_02:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=40 phishscore=0 bulkscore=0 spamscore=0 clxscore=1011 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1906280000 definitions=main-1908270117 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Qian Cai , Madhavan Srinivasan , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Commit <684d984038aa> ('powerpc/powernv: Add debugfs interface for imc-mode and imc') added debugfs interface for the nest imc pmu devices to support changing of different ucode modes. Primarily adding this capability for debug. But when doing so, the code did not consider the case of cpu-less nodes. So when reading the _cmd_ or _mode_ file of a cpu-less node will create this crash. [ 1139.415461][ T5301] Faulting instruction address: 0xc0000000000d0d58 [ 1139.415492][ T5301] Oops: Kernel access of bad area, sig: 11 [#1] [ 1139.415509][ T5301] LE PAGE_SIZE=64K MMU=Radix MMU=Hash SMP NR_CPUS=256 DEBUG_PAGEALLOC NUMA PowerNV [ 1139.415542][ T5301] Modules linked in: i2c_opal i2c_core ip_tables x_tables xfs sd_mod bnx2x mdio ahci libahci tg3 libphy libata firmware_class dm_mirror dm_region_hash dm_log dm_mod [ 1139.415595][ T5301] CPU: 67 PID: 5301 Comm: cat Not tainted 5.2.0-rc6-next- 20190627+ #19 [ 1139.415634][ T5301] NIP: c0000000000d0d58 LR: c00000000049aa18 CTR:c0000000000d0d50 [ 1139.415675][ T5301] REGS: c00020194548f9e0 TRAP: 0300 Not tainted (5.2.0-rc6-next-20190627+) [ 1139.415705][ T5301] MSR: 9000000000009033 CR:28022822 XER: 00000000 [ 1139.415777][ T5301] CFAR: c00000000049aa14 DAR: 000000000003fc08 DSISR:40000000 IRQMASK: 0 [ 1139.415777][ T5301] GPR00: c00000000049aa18 c00020194548fc70 c0000000016f8b00000000000003fc08 [ 1139.415777][ T5301] GPR04: c00020194548fcd0 0000000000000000 0000000014884e73ffffffff00011eaa [ 1139.415777][ T5301] GPR08: 000000007eea5a52 c0000000000d0d50 00000000000000000000000000000000 [ 1139.415777][ T5301] GPR12: c0000000000d0d50 c000201fff7f8c00 00000000000000000000000000000000 [ 1139.415777][ T5301] GPR16: 000000000000000d 00007fffeb0c3368 ffffffffffffffff0000000000000000 [ 1139.415777][ T5301] GPR20: 0000000000000000 0000000000000000 00000000000000000000000000020000 [ 1139.415777][ T5301] GPR24: 0000000000000000 0000000000000000 0000000000020000000000010ec90000 [ 1139.415777][ T5301] GPR28: c00020194548fdf0 c00020049a584ef8 0000000000000000c00020049a584ea8 [ 1139.416116][ T5301] NIP [c0000000000d0d58] imc_mem_get+0x8/0x20 [ 1139.416143][ T5301] LR [c00000000049aa18] simple_attr_read+0x118/0x170 [ 1139.416158][ T5301] Call Trace: [ 1139.416182][ T5301] [c00020194548fc70] [c00000000049a970]simple_attr_read+0x70/0x170 (unreliable) [ 1139.416255][ T5301] [c00020194548fd10] [c00000000054385c]debugfs_attr_read+0x6c/0xb0 [ 1139.416305][ T5301] [c00020194548fd60] [c000000000454c1c]__vfs_read+0x3c/0x70 [ 1139.416363][ T5301] [c00020194548fd80] [c000000000454d0c] vfs_read+0xbc/0x1a0 [ 1139.416392][ T5301] [c00020194548fdd0] [c00000000045519c]ksys_read+0x7c/0x140 [ 1139.416434][ T5301] [c00020194548fe20] [c00000000000b108]system_call+0x5c/0x70 [ 1139.416473][ T5301] Instruction dump: [ 1139.416511][ T5301] 4e800020 60000000 7c0802a6 60000000 7c801d28 38600000 4e800020 60000000 [ 1139.416572][ T5301] 60000000 60000000 7c0802a6 60000000 <7d201c28> 38600000 f9240000 4e800020 [ 1139.416636][ T5301] ---[ end trace c44d1fb4ace04784 ]--- [ 1139.520686][ T5301] [ 1140.520820][ T5301] Kernel panic - not syncing: Fatal exception Patch fixes the issue with a more robust check for vbase to NULL. Before patch, ls output for the debugfs imc directory # ls /sys/kernel/debug/powerpc/imc/ imc_cmd_0 imc_cmd_251 imc_cmd_253 imc_cmd_255 imc_mode_0 imc_mode_251 imc_mode_253 imc_mode_255 imc_cmd_250 imc_cmd_252 imc_cmd_254 imc_cmd_8 imc_mode_250 imc_mode_252 imc_mode_254 imc_mode_8 After patch, ls output for the debugfs imc directory # ls /sys/kernel/debug/powerpc/imc/ imc_cmd_0 imc_cmd_8 imc_mode_0 imc_mode_8 Actual bug here is that, we have two loops with potentially different loop counts. That is, in imc_get_mem_addr_nest(), loop count is obtained from the dt entries. But incase of export_imc_mode_and_cmd(), loop was based on for_each_nid() count. Patch fixes the loop count in latter based on the struct mem_info. Ideally it would be better to have array size in struct imc_pmu. Fixes: 684d984038aa ('powerpc/powernv: Add debugfs interface for imc-mode and imc') Reported-by: Qian Cai Suggested-by: Michael Ellerman Signed-off-by: Madhavan Srinivasan --- Changelog v2: - No logic changes. - Just added more commit message. Changelog v1: - Modified the cpumask check. arch/powerpc/platforms/powernv/opal-imc.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/arch/powerpc/platforms/powernv/opal-imc.c b/arch/powerpc/platforms/powernv/opal-imc.c index 186109bdd41b..e04b20625cb9 100644 --- a/arch/powerpc/platforms/powernv/opal-imc.c +++ b/arch/powerpc/platforms/powernv/opal-imc.c @@ -53,9 +53,9 @@ static void export_imc_mode_and_cmd(struct device_node *node, struct imc_pmu *pmu_ptr) { static u64 loc, *imc_mode_addr, *imc_cmd_addr; - int chip = 0, nid; char mode[16], cmd[16]; u32 cb_offset; + struct imc_mem_info *ptr = pmu_ptr->mem_info; imc_debugfs_parent = debugfs_create_dir("imc", powerpc_debugfs_root); @@ -69,20 +69,20 @@ static void export_imc_mode_and_cmd(struct device_node *node, if (of_property_read_u32(node, "cb_offset", &cb_offset)) cb_offset = IMC_CNTL_BLK_OFFSET; - for_each_node(nid) { - loc = (u64)(pmu_ptr->mem_info[chip].vbase) + cb_offset; + while (ptr->vbase != NULL) { + loc = (u64)(ptr->vbase) + cb_offset; imc_mode_addr = (u64 *)(loc + IMC_CNTL_BLK_MODE_OFFSET); - sprintf(mode, "imc_mode_%d", nid); + sprintf(mode, "imc_mode_%d", (u32)(ptr->id)); if (!imc_debugfs_create_x64(mode, 0600, imc_debugfs_parent, imc_mode_addr)) goto err; imc_cmd_addr = (u64 *)(loc + IMC_CNTL_BLK_CMD_OFFSET); - sprintf(cmd, "imc_cmd_%d", nid); + sprintf(cmd, "imc_cmd_%d", (u32)(ptr->id)); if (!imc_debugfs_create_x64(cmd, 0600, imc_debugfs_parent, imc_cmd_addr)) goto err; - chip++; + ptr++; } return; -- 2.21.0