From patchwork Fri Jul 12 12:20:02 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 168949 Delivered-To: patch@linaro.org Received: by 2002:a92:4782:0:0:0:0:0 with SMTP id e2csp829603ilk; Fri, 12 Jul 2019 05:36:55 -0700 (PDT) X-Google-Smtp-Source: APXvYqzCwokMqNzOxKNxeDpxY65jXV9Gl6F0W5rQGMKtfubtzFYFrDBiu/rlowTgRz/jEwhTnHh9 X-Received: by 2002:a17:90a:2244:: with SMTP id c62mr11791773pje.29.1562935015826; Fri, 12 Jul 2019 05:36:55 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1562935015; cv=none; d=google.com; s=arc-20160816; b=ytGcTNe1EBqwLOnX5Et4j9PBUUsruiV0t0lmp5EHsW7BMbIXiaPHCcqJAkJcDtBlf2 N9c2lfYsCFv61d5Rb8PDFdhCu++7JzAwcwOr3thPzIR2JZRmBLMK00uqnNb8zJm+nR18 I2vqLYGVwXLDpAb2htznpjZqCkuyhgrh5VvlMthN/Cg1MzWiDaNdgk2NbIufySGGR/cG nf2bS0j+i1MilPVOQTxRz4eK7QPohipHkt62OPY7dJ0QhARgfptV7Do+UR74SL5a07qy xRbt1rI8gubfL1XL1vpnIz7nVc7qzfQi5LuecnNDbTCMGnsuusgT5Kq20rGrA5sHcokf +lnA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:mime-version :user-agent:references:in-reply-to:message-id:date:subject:cc:to :from:dkim-signature; bh=+jMYBUOy5tli1WvklO7xVIO33E6GUV4uu05BgoJaOBc=; b=o0mxbY7SB/odWpTT1lE/xYo0EOc3xc1rpnafl13H2WdgwiWrFSmtY3I7xJkqLpg38a cvtQ6nikbuyFgWqbf482n0FyvuqDc6zCtnIrRlAF2MHp0iGAKrUsa6T954beurf0Raql /77U/8QZNSzXjgFdentoj5+QbhMdY4S6V/ZaOsqstyeqjwz414YMD7D2MxqzsvGYLWQN YUw3BDq9f8a9MlpjAKcXG6mi3Oayu5pL2/rP9YY715rmOqy8zRpzKv/UYlLPkezs5P8i 11lecfzMGNwf4GU6/RMec4+ZCMzc/hJOX1UQIpIKT+DsaA+Ek9EsUslsoFkifnNp2fz0 2+jA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=N4EDyVKO; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id v16si8368635pfi.142.2019.07.12.05.36.51; Fri, 12 Jul 2019 05:36:55 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=N4EDyVKO; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728363AbfGLMe6 (ORCPT + 29 others); Fri, 12 Jul 2019 08:34:58 -0400 Received: from mail.kernel.org ([198.145.29.99]:55130 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729806AbfGLMez (ORCPT ); Fri, 12 Jul 2019 08:34:55 -0400 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 43CAB21019; Fri, 12 Jul 2019 12:34:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1562934894; bh=uPUXM/BI4w3s7rvxlZBhJzyXa56qhpQue+XkMMoOEJ4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=N4EDyVKO1zujb8zypEZ3ESMSRUe1kF+iikWYf3j+14M+69bJlmi5/gDfRiM16IR64 WVEbL6gTK/43Qdj7zibC0jziBIC+4gk8CO+6zOY3m3/nhMVwM6whhtRh66B6dqAlG8 x6JQdPOVg9dVDn5Ad9ruvc7Lo8PYs4jqrxZBMvPk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mathieu Poirier , Suzuki K Poulose Subject: [PATCH 5.2 49/61] coresight: tmc-etf: Do not call smp_processor_id from preemptible Date: Fri, 12 Jul 2019 14:20:02 +0200 Message-Id: <20190712121623.299347656@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190712121620.632595223@linuxfoundation.org> References: <20190712121620.632595223@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Suzuki K Poulose commit 024c1fd9dbcc1d8a847f1311f999d35783921b7f upstream. 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/2544 caller is tmc_alloc_etf_buffer+0x5c/0x60 CPU: 2 PID: 2544 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_etf_buffer+0x5c/0x60 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: 2e499bbc1a929ac ("coresight: tmc: implementing TMC-ETF AUX space API") Cc: Mathieu Poirier Signed-off-by: Suzuki K Poulose Cc: stable # 4.7+ Signed-off-by: Mathieu Poirier Link: https://lore.kernel.org/r/20190620221237.3536-4-mathieu.poirier@linaro.org Signed-off-by: Greg Kroah-Hartman --- drivers/hwtracing/coresight/coresight-tmc-etf.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) --- a/drivers/hwtracing/coresight/coresight-tmc-etf.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c @@ -378,12 +378,10 @@ static void *tmc_alloc_etf_buffer(struct struct perf_event *event, void **pages, int nr_pages, bool overwrite) { - int node, cpu = event->cpu; + int node; struct cs_buffers *buf; - if (cpu == -1) - cpu = smp_processor_id(); - node = cpu_to_node(cpu); + node = (event->cpu == -1) ? NUMA_NO_NODE : cpu_to_node(event->cpu); /* Allocate memory structure for interaction with Perf */ buf = kzalloc_node(sizeof(struct cs_buffers), GFP_KERNEL, node);