From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754299AbdKNKP0 (ORCPT ); Tue, 14 Nov 2017 05:15:26 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:55978 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754110AbdKNKPP (ORCPT ); Tue, 14 Nov 2017 05:15:15 -0500 Subject: Re: [PATCH 16/35] perf annotate: Add samples into struct annotation_line To: Jiri Olsa Cc: Jiri Olsa , Arnaldo Carvalho de Melo , lkml , Ingo Molnar , Namhyung Kim , David Ahern , Peter Zijlstra , Andi Kleen , ravi.bangoria@linux.vnet.ibm.com References: <20171011150158.11895-1-jolsa@kernel.org> <20171011150158.11895-17-jolsa@kernel.org> <20171113201438.GB26900@krava> <20171114093114.GA25679@krava> From: Ravi Bangoria Date: Tue, 14 Nov 2017 15:45:27 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.4.0 MIME-Version: 1.0 In-Reply-To: <20171114093114.GA25679@krava> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-TM-AS-GCONF: 00 x-cbid: 17111410-0016-0000-0000-000005010C63 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17111410-0017-0000-0000-0000283CC2F2 Message-Id: <2d6af5ff-dad9-f2a1-e183-5dc79f91702b@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-11-14_05:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 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-1711140139 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Jiri, On 11/14/2017 03:01 PM, Jiri Olsa wrote: > On Mon, Nov 13, 2017 at 09:14:38PM +0100, Jiri Olsa wrote: >> On Mon, Nov 13, 2017 at 09:16:20PM +0530, Ravi Bangoria wrote: >>> Hi Jiri, >>> >>> This patch seems to be causing segfault with "perf top --stdio". >>> >>> Steps to reproduce: >>> 1. start "perf top --stdio" in one terminal >>> 2. run some simple workload in another terminal, let it get finished. >>> 3. annotate function from previous workload in perf top (press 'a' followed >>> by 's') >>> >>> Perf will crash with: >>> >>>   perf: Segmentation fault >>>   Obtained 8 stack frames. >>>   ./perf(sighandler_dump_stack+0x3e) [0x4f1b6e] >>>   /lib64/libc.so.6(+0x36a7f) [0x7ff3aa7e4a7f] >>>   ./perf() [0x4a27fd] >>>   ./perf(symbol__annotate+0x199) [0x4a4439] >>>   ./perf() [0x44e32d] >>>   ./perf() [0x44f098] >>>   /lib64/libpthread.so.0(+0x736c) [0x7ff3acee836c] >>>   /lib64/libc.so.6(clone+0x3e) [0x7ff3aa8bee1e] >>> >>> Can you please check. >> hum, I'm getting following crash after resizing the terminal window: >> >> perf: Floating point exception >> Obtained 8 stack frames. >> ./perf(dump_stack+0x2e) [0x510c89] >> ./perf(sighandler_dump_stack+0x2e) [0x510d69] >> /lib64/libc.so.6(+0x36a80) [0x7f9419588a80] >> ./perf(perf_top__header_snprintf+0x208) [0x4f42c1] >> ./perf() [0x453c09] >> ./perf() [0x454ddb] >> /lib64/libpthread.so.0(+0x736d) [0x7f941bc8c36d] >> /lib64/libc.so.6(clone+0x3f) [0x7f9419662e1f] >> Floating point exception (core dumped) >> >> working on fix > so my crash is caused by bogus resize code, I have it working with fix for > memory corruption happening in SIGWINCH signal handler (attached) > could you please check if that fixes the code for you? Yes, this fixes the crash caused by resize. But original crash I reported is still there. Issue seems to be with evsel being NULL and we are trying to de-reference it somewhere inside annotation_line__new(). Will try to spend more time on it. -Ravi