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=-2.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 9CBFBC04EB8 for ; Thu, 6 Dec 2018 08:17:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 57615214DA for ; Thu, 6 Dec 2018 08:17:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="Gc+3AsB7" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 57615214DA Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729116AbeLFIRS (ORCPT ); Thu, 6 Dec 2018 03:17:18 -0500 Received: from merlin.infradead.org ([205.233.59.134]:46346 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727575AbeLFIRR (ORCPT ); Thu, 6 Dec 2018 03:17:17 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=+4aWexOyAMuaR3Q8yxnhpD/XfI0eZvjTj4dnIj/xzSY=; b=Gc+3AsB73CX7Oh/POOqK5nYUT 2ezVI8vKyu9L1PaUV7sR/ETaAfsaM8M/oO4GFd6+zTnEDVDH7l1Y258hsArAdwsuWBkzZ8VbpU9ab i8iYiS3gjNLU3A2nuDMk1gw7TQkjDY0uEhCzlZKU2D2tnv8JnmrSQRr46pod21V9vvNaOLLLcOJIx 3plHguRdn1CUfYPE+NXjGhR2lihLv3bhlzGzpgDZiXutYm/HbR44xmVdSxolDYV64wrn5Ui8cvZ+K 2chg7aR8UnEsmRLYqnW3SDtPZE377KpAhNDDplM+xaODdi2LDgHzsNSyMsjSykTKnmjoFuZIyi8uQ Kg7eOkbFA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1gUoqL-0004vW-0f; Thu, 06 Dec 2018 08:17:09 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id C7B2A2029F883; Thu, 6 Dec 2018 09:17:07 +0100 (CET) Date: Thu, 6 Dec 2018 09:17:07 +0100 From: Peter Zijlstra To: Jiri Olsa Cc: Arnaldo Carvalho de Melo , Steven Rostedt , lkml , Ingo Molnar , Namhyung Kim , Alexander Shishkin , Thomas Gleixner , "Luis Claudio R. Goncalves" , ldv@altlinux.org, esyr@redhat.com, Frederic Weisbecker Subject: Re: [PATCH 1/8] perf: Allow to block process in syscall tracepoints Message-ID: <20181206081707.GF4234@hirez.programming.kicks-ass.net> References: <20181205160509.1168-1-jolsa@kernel.org> <20181205160509.1168-2-jolsa@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181205160509.1168-2-jolsa@kernel.org> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Dec 05, 2018 at 05:05:02PM +0100, Jiri Olsa wrote: > @@ -10461,6 +10484,19 @@ SYSCALL_DEFINE5(perf_event_open, > return -EINVAL; > } > > + if (attr.block) { > + /* > + * Allow only syscall tracepoints, check for syscall class > + * is made in the tracepoint event_init callback. > + */ > + if (attr.type != PERF_TYPE_TRACEPOINT) > + return -EINVAL; > + > + /* Allow to block only if we attach to a process. */ > + if (pid == -1) > + return -EINVAL; > + } > + > /* Only privileged users can get physical addresses */ > if ((attr.sample_type & PERF_SAMPLE_PHYS_ADDR) && > perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) That's fairly horrible and will, when copied, lead to a giant mess. Please see the whole exclusion patch set here: https://lkml.kernel.org/r/1543230756-15319-1-git-send-email-andrew.murray@arm.com PERF_PMU_CAP_BLOCK sounds like something you'd want here.