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=-5.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 80179C43613 for ; Thu, 20 Jun 2019 06:03:47 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 54D3B20B1F for ; Thu, 20 Jun 2019 06:03:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="oyMFhZa1"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="hCBDItWa" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 54D3B20B1F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-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=bombadil.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=lTgKGTW7bJ5HlHPanvaD1qg94tuWJ4hGe9js1sv6ItA=; b=oyMFhZa156NRw6 IjQVjhjIdoXYQfhB+YS7J9qtN6GcuO0Ekq3+VSU2C51hvU/kO4mNLopu8txZx70ZI6c7jtqlsVyvp uiOq2Opo0X7tQUmCyNNCQHP5CE0C/1GQl5hxWOXmm8BxAGCy6DELY4czCPcl2PUouZ4jdmN47Azc5 XH9x8zOoxdedyXV1p9iJXUesYkt1H40XZbktfgo3u7pManbj6UTcUEIfGi69PvzVLj5A0SY76gx1w CkKp8RtEuOClLUjwTnO8xptddaJXe41aojrbq8arGiNeP2d2eCUqLgMEedxsHqC/quRQ1CNfOO0pz /4LVk5iFRknVO80JYduQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1hdqAb-0000EB-7Z; Thu, 20 Jun 2019 06:03:37 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.92 #3 (Red Hat Linux)) id 1hdqAY-0000Dq-PZ for linux-arm-kernel@lists.infradead.org; Thu, 20 Jun 2019 06:03:36 +0000 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0F0DB214AF; Thu, 20 Jun 2019 06:03:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561010614; bh=9Jew5N8mxFb7qH55R16PuNVnR2rJvYvHe2o10XI/SBc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=hCBDItWao1vk4cZi+RCgYvitlrixR9tyHTmVl9+2M0X2USgND690dwdyhEqwTyRIz e8xEYh/+gtB4wLfsWaWZH17HXVSUzVmb326RsiY7klT2qwwb/voTaUhCuDLP+NpBu4 +ByNcOvl9Cxo/cqzzOf8rqdw62ripoEyepINnxpA= Date: Thu, 20 Jun 2019 08:03:32 +0200 From: Greg KH To: Mathieu Poirier Subject: Re: [PATCH 21/28] coresight: tmc-etr: alloc_perf_buf: Do not call smp_processor_id from preemptible Message-ID: <20190620060332.GB26319@kroah.com> References: <20190619195318.19254-1-mathieu.poirier@linaro.org> <20190619195318.19254-22-mathieu.poirier@linaro.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20190619195318.19254-22-mathieu.poirier@linaro.org> User-Agent: Mutt/1.12.1 (2019-06-15) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190619_230334_839663_F59B5A1C X-CRM114-Status: GOOD ( 12.94 ) 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: linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Jun 19, 2019 at 01:53:11PM -0600, Mathieu Poirier wrote: > From: Suzuki K Poulose > > During a perf session we try to allocate buffers on the "node" associated > with the CPU the event is bound to. If it is not bound to a CPU, we > use the current CPU node, using smp_processor_id(). However this is unsafe > in a pre-emptible context and could generate the splats as below : > > BUG: using smp_processor_id() in preemptible [00000000] code: perf/1743 > caller is tmc_alloc_etr_buffer+0x1bc/0x1f0 > CPU: 1 PID: 1743 Comm: perf Not tainted 5.1.0-rc6-147786-g116841e #344 > Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno Development Platform, BIOS EDK II Feb 1 2019 > Call trace: > dump_backtrace+0x0/0x150 > show_stack+0x14/0x20 > dump_stack+0x9c/0xc4 > debug_smp_processor_id+0x10c/0x110 > tmc_alloc_etr_buffer+0x1bc/0x1f0 > etm_setup_aux+0x1c4/0x230 > rb_alloc_aux+0x1b8/0x2b8 > perf_mmap+0x35c/0x478 > mmap_region+0x34c/0x4f0 > do_mmap+0x2d8/0x418 > vm_mmap_pgoff+0xd0/0xf8 > ksys_mmap_pgoff+0x88/0xf8 > __arm64_sys_mmap+0x28/0x38 > el0_svc_handler+0xd8/0x138 > el0_svc+0x8/0xc > > Use NUMA_NO_NODE hint instead of using the current node for events > not bound to CPUs. > > Fixes: 22f429f19c4135d51e9 ("coresight: etm-perf: Add support for ETR backend") > Cc: Mathieu Poirier > Signed-off-by: Suzuki K Poulose > Signed-off-by: Mathieu Poirier Same here, why isn't this 5.2-final and stable@vger.kernel.org material? _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel