From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932791AbbFIHeh (ORCPT ); Tue, 9 Jun 2015 03:34:37 -0400 Received: from mail-db3on0067.outbound.protection.outlook.com ([157.55.234.67]:10688 "EHLO emea01-db3-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932646AbbFIHe1 (ORCPT ); Tue, 9 Jun 2015 03:34:27 -0400 Authentication-Results: spf=fail (sender IP is 212.179.42.66) smtp.mailfrom=ezchip.com; vger.kernel.org; dkim=none (message not signed) header.d=none; From: Gil Fruchter To: , CC: , , , , Gil Fruchter Subject: [PATCH v2 2/2] tracing: Fix for non-continuous cpu ids Date: Tue, 9 Jun 2015 10:32:35 +0300 Message-ID: <1433835155-6894-3-git-send-email-gilf@ezchip.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1433251589-21013-1-git-send-email-gilf@ezchip.com> References: <1433251589-21013-1-git-send-email-gilf@ezchip.com> MIME-Version: 1.0 Content-Type: text/plain X-TM-AS-Product-Ver: SMEX-11.0.0.1191-7.500.1018-21534.006 X-TM-AS-Result: No--5.712200-8.000000-31 X-TM-AS-User-Approved-Sender: No X-TM-AS-User-Blocked-Sender: No X-EOPAttributedMessage: 0 X-Microsoft-Exchange-Diagnostics: 1;DB3FFO11FD019;1:CL2EtTxrsafBXYop2F0WjHMgkk/HU00hcEO/dZgBxz1gbV40VfmDhjGpJz4ZgwdQq63r2kuOD6eVW3nHNlyIN86JIuKUxq/+uBXp5lpRhn4A8xBxkt57ZCOm0Z6Q8vQ0TgVmMtAT6ijmv2VA9XjbStNRVF263CGOS2jVdM3SHXqRwQcXzG7HbY4Z+zs+lmnM5LfarBd3mjUQ0o4weGRaX1dM96dUK1Pl0UELP7duAHVHicO5tmKLZSBFfVc6g8TQVRbfDVwX10WPbH96qMOw/v6ursUR9mW1RyTzs+zEeYLMv5Z4D/sgGYFQD6nI7jB1 X-Forefront-Antispam-Report: CIP:212.179.42.66;CTRY:IL;IPV:NLI;EFV:NLI;SFV:NSPM;SFS:(10009020)(6009001)(339900001)(189002)(199003)(107886002)(46102003)(5001970100001)(77096005)(50466002)(48376002)(76176999)(106466001)(6806004)(50986999)(189998001)(47776003)(49486002)(86362001)(575784001)(104016003)(2950100001)(33646002)(5001770100001)(19580405001)(105606002)(19580395003)(87936001)(92566002)(85426001)(77156002)(62966003)(229853001)(36756003)(50226001)(4001430100001);DIR:OUT;SFP:1101;SCL:1;SRVR:AMSPR02MB181;H:ezex10.ezchip.com;FPR:;SPF:Fail;MLV:sfv;MX:1;A:1;LANG:en; X-Microsoft-Antispam: UriScan:;BCL:0;PCL:0;RULEID:;SRVR:AMSPR02MB181; X-Microsoft-Antispam-PRVS: X-Exchange-Antispam-Report-Test: UriScan:; X-Exchange-Antispam-Report-CFA-Test: BCL:0;PCL:0;RULEID:(601004)(520003)(5005006)(3002001);SRVR:AMSPR02MB181;BCL:0;PCL:0;RULEID:;SRVR:AMSPR02MB181; X-Forefront-PRVS: 06022AA85F X-OriginatorOrg: ezchip.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Jun 2015 07:34:24.8850 (UTC) X-MS-Exchange-CrossTenant-Id: 0fc16e0a-3cd3-4092-8b2f-0a42cff122c3 X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=0fc16e0a-3cd3-4092-8b2f-0a42cff122c3;Ip=[212.179.42.66];Helo=[ezex10.ezchip.com] X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: AMSPR02MB181 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently exception occures due to access beyond buffer_iter range while using index of cpu bigger than num_possible_cpus(). Below there is an example for such exception when we use cpus 0,1,16,17. In order to fix buffer allocation size for non-continuous cpu ids we allocate according to the max cpu id and not according to the amount of possible cpus. Example: $ cat /sys/kernel/debug/tracing/per_cpu/cpu1/trace Path: /bin/busybox CPU: 0 PID: 82 Comm: cat Not tainted 4.0.0 #29 task: 80734c80 ti: 80012000 task.ti: 80012000 [ECR ]: 0x00220100 => Invalid Read @ 0x00000000 by insn @ 0x800abafc [EFA ]: 0x00000000 [BLINK ]: ring_buffer_read_finish+0x24/0x64 [ERET ]: rb_check_pages+0x20/0x188 [STAT32]: 0x00001a00 : BTA: 0x800abafc SP: 0x80013f0c FP: 0x57719cf8 LPS: 0x200036b4 LPE: 0x200036b8 LPC: 0x00000000 r00: 0x8002aca0 r01: 0x00001606 r02: 0x00000000 r03: 0x00000001 r04: 0x00000000 r05: 0x804b4954 r06: 0x00030003 r07: 0x8002a260 r08: 0x00000286 r09: 0x00080002 r10: 0x00001006 r11: 0x807351a4 r12: 0x00000001 Stack Trace: rb_check_pages+0x20/0x188 ring_buffer_read_finish+0x24/0x64 tracing_release+0x4e/0x170 __fput+0x62/0x158 task_work_run+0xa2/0xd4 do_notify_resume+0x52/0x7c resume_user_mode_begin+0xdc/0xe0 Signed-off-by: Noam Camus Signed-off-by: Gil Fruchter --- kernel/trace/trace.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 57ffc4a..8c5b382 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3034,7 +3034,7 @@ __tracing_open(struct inode *inode, struct file *file, bool snapshot) if (!iter) return ERR_PTR(-ENOMEM); - iter->buffer_iter = kcalloc(num_possible_cpus(), sizeof(*iter->buffer_iter), + iter->buffer_iter = kcalloc(nr_cpu_ids, sizeof(*iter->buffer_iter), GFP_KERNEL); if (!iter->buffer_iter) goto release; -- 1.7.1