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=-3.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 73E1DC388F9 for ; Fri, 23 Oct 2020 09:42:34 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 E259820760 for ; Fri, 23 Oct 2020 09:42:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="WNjELLDd" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E259820760 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-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=eIGXeB7dJv2NCu28YeUxyaHOIa1bG1iAht2KwEFwPVo=; b=WNjELLDd3l2QA+T77Yi7xmrhW eim5A+VAY3T4XYiNElZOi/lshXYScrCrPypfmfRzEI4bIKzZiUFQrny74Wvwq6SEStt3Ne6cPSpZA SB2g4eCP0LzAsQrNUnPpprgD0S1wo6g/KpcPN0ya67PQKborUfZixvV2/dkohwSuvGuYeq0Y2W9it fXeJ8LL4JQ/hYZ3QWN/Wed0qYdEx/uZmhDjh9AMlAplWy7Y/FrhHAmOznT33fSr1N04MlZ9GPDtQX PpvKKmqYzwFk2nz1wtXb2UWT9zdx1CyE+ZTcxWkG4Rtx08tY1bG33sBusXYWhZInZ1bm3UoIR2cfE aCF5LGavg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kVtZX-0005T0-KP; Fri, 23 Oct 2020 09:41:19 +0000 Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kVtZU-0005So-Ov; Fri, 23 Oct 2020 09:41:16 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 698B7304D2B; Fri, 23 Oct 2020 11:41:15 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 5005E2B945263; Fri, 23 Oct 2020 11:41:15 +0200 (CEST) Date: Fri, 23 Oct 2020 11:41:15 +0200 From: Peter Zijlstra To: Suzuki Poulose Subject: Re: [PATCHv2 2/4] coresight: tmc-etf: Fix NULL ptr dereference in tmc_enable_etf_sink_perf() Message-ID: <20201023094115.GR2611@hirez.programming.kicks-ass.net> References: <20201022113214.GD2611@hirez.programming.kicks-ass.net> <20201022150609.GI2611@hirez.programming.kicks-ass.net> <788706f2-0670-b7b6-a153-3ec6f16e0f2e@arm.com> <20201022212033.GA646497@xps15> <20201023073905.GM2611@hirez.programming.kicks-ass.net> <174e6461-4d46-cb65-c094-c06ee3b21568@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <174e6461-4d46-cb65-c094-c06ee3b21568@arm.com> X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Sai Prakash Ranjan , Mathieu Poirier , Alexander Shishkin , linux-arm-msm@vger.kernel.org, coresight@lists.linaro.org, linux-kernel@vger.kernel.org, Arnaldo Carvalho de Melo , Stephen Boyd , Ingo Molnar , Namhyung Kim , Jiri Olsa , linux-arm-kernel@lists.infradead.org, Mike Leach Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Oct 23, 2020 at 09:49:53AM +0100, Suzuki Poulose wrote: > On 10/23/20 8:39 AM, Peter Zijlstra wrote: > > So then I don't understand the !->owner issue, that only happens when > > the task dies, which cannot be concurrent with event creation. Are you > > Part of the patch from Sai, fixes this by avoiding the dereferencing > after event creation (by caching it). But the kernel events needs > fixing. I'm fundamentally failing here. Creating a link to the sink is strictly event-creation time. Why would you ever need it again later? Later you already have the sink setup. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel