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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 077BFC2BA2B for ; Tue, 7 Apr 2020 14:54:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D48322078C for ; Tue, 7 Apr 2020 14:54:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728979AbgDGOyf (ORCPT ); Tue, 7 Apr 2020 10:54:35 -0400 Received: from mga06.intel.com ([134.134.136.31]:25333 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728855AbgDGOyf (ORCPT ); Tue, 7 Apr 2020 10:54:35 -0400 IronPort-SDR: vzH2e/ETbj/Ls1bFDYAfNn5Ele1iE+N+3Ma3JrI+SPdUsapHZh3oUD0xO1TfDoiD54Jj6HW3PF /HcFSleC2vkQ== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Apr 2020 07:54:34 -0700 IronPort-SDR: cOZmMIE0ak5uQfYildm7qw134FQCkEL1T7TEy6C+ICKnfA8A0r6yAgOesc5pOEYZpwGdg1fk17 thIr/oSRo8dA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.72,354,1580803200"; d="scan'208";a="254480922" Received: from linux.intel.com ([10.54.29.200]) by orsmga006.jf.intel.com with ESMTP; 07 Apr 2020 07:54:34 -0700 Received: from [10.249.224.62] (abudanko-mobl.ccr.corp.intel.com [10.249.224.62]) by linux.intel.com (Postfix) with ESMTP id D324C5802BC; Tue, 7 Apr 2020 07:54:28 -0700 (PDT) Subject: Re: [PATCH v8 00/12] Introduce CAP_PERFMON to secure system performance monitoring and observability To: Arnaldo Carvalho de Melo Cc: Peter Zijlstra , Alexei Starovoitov , Ingo Molnar , James Morris , Namhyung Kim , Serge Hallyn , Jiri Olsa , Song Liu , Andi Kleen , Stephane Eranian , Igor Lubashev , Thomas Gleixner , linux-kernel , "linux-security-module@vger.kernel.org" , "selinux@vger.kernel.org" , "intel-gfx@lists.freedesktop.org" , "linux-doc@vger.kernel.org" , linux-man@vger.kernel.org References: <20200407143014.GD11186@kernel.org> <20200407143551.GF11186@kernel.org> From: Alexey Budankov Organization: Intel Corp. Message-ID: <10cc74ee-8587-8cdb-f85f-5724b370a2ce@linux.intel.com> Date: Tue, 7 Apr 2020 17:54:27 +0300 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 MIME-Version: 1.0 In-Reply-To: <20200407143551.GF11186@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-man-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-man@vger.kernel.org On 07.04.2020 17:35, Arnaldo Carvalho de Melo wrote: > Em Tue, Apr 07, 2020 at 11:30:14AM -0300, Arnaldo Carvalho de Melo escreveu: >> [perf@five ~]$ type perf >> perf is hashed (/home/perf/bin/perf) >> [perf@five ~]$ getcap /home/perf/bin/perf >> /home/perf/bin/perf = cap_sys_ptrace,cap_syslog,38+ep >> [perf@five ~]$ groups >> perf perf_users >> [perf@five ~]$ id >> uid=1002(perf) gid=1002(perf) groups=1002(perf),1003(perf_users) context=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 >> [perf@five ~]$ perf top --stdio >> Error: >> Failed to mmap with 1 (Operation not permitted) >> [perf@five ~]$ perf record -a >> ^C[ perf record: Woken up 1 times to write data ] >> [ perf record: Captured and wrote 1.177 MB perf.data (1552 samples) ] >> >> [perf@five ~]$ perf evlist >> cycles:u >> [perf@five ~]$ > > Humm, perf record falls back to cycles:u after initially trying cycles > (i.e. kernel and userspace), lemme see trying 'perf top -e cycles:u', > lemme test, humm not really: > > [perf@five ~]$ perf top --stdio -e cycles:u > Error: > Failed to mmap with 1 (Operation not permitted) > [perf@five ~]$ perf record -e cycles:u -a sleep 1 > [ perf record: Woken up 1 times to write data ] > [ perf record: Captured and wrote 1.123 MB perf.data (132 samples) ] > [perf@five ~]$ > > Back to debugging this. Could makes sense adding cap_ipc_lock to the binary to isolate from this: kernel/events/core.c: 6101 if ((locked > lock_limit) && perf_is_paranoid() && !capable(CAP_IPC_LOCK)) { ret = -EPERM; goto unlock; } ~Alexey