diff options
Diffstat (limited to 'cpufreq-powernow-k8-Initialize-per-cpu-data-structures-properly.patch')
| -rw-r--r-- | cpufreq-powernow-k8-Initialize-per-cpu-data-structures-properly.patch | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/cpufreq-powernow-k8-Initialize-per-cpu-data-structures-properly.patch b/cpufreq-powernow-k8-Initialize-per-cpu-data-structures-properly.patch new file mode 100644 index 000000000..70a553d2c --- /dev/null +++ b/cpufreq-powernow-k8-Initialize-per-cpu-data-structures-properly.patch @@ -0,0 +1,138 @@ +Bugzilla: 1054408 +Upstream-status: Queued for 3.14 and CC'd to stable +Delivered-To: jwboyer@gmail.com +Received: by 10.76.82.162 with SMTP id j2csp112184oay; + Mon, 17 Feb 2014 03:01:52 -0800 (PST) +X-Received: by 10.68.164.4 with SMTP id ym4mr26078759pbb.53.1392634911720; + Mon, 17 Feb 2014 03:01:51 -0800 (PST) +Return-Path: <linux-kernel-owner@vger.kernel.org> +Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) + by mx.google.com with ESMTP id xf4si14383267pab.191.2014.02.17.03.01.15 + for <multiple recipients>; + Mon, 17 Feb 2014 03:01:51 -0800 (PST) +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; + 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.mail=linux-kernel-owner@vger.kernel.org +Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand + id S1752151AbaBQKyA (ORCPT <rfc822;gardner.ben.linux@gmail.com> + + 99 others); Mon, 17 Feb 2014 05:54:00 -0500 +Received: from e28smtp06.in.ibm.com ([122.248.162.6]:51044 "EHLO + e28smtp06.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org + with ESMTP id S1752134AbaBQKx6 (ORCPT + <rfc822;linux-kernel@vger.kernel.org>); + Mon, 17 Feb 2014 05:53:58 -0500 +Received: from /spool/local + by e28smtp06.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted + for <linux-kernel@vger.kernel.org> from <srivatsa.bhat@linux.vnet.ibm.com>; + Mon, 17 Feb 2014 16:23:53 +0530 +Received: from d28dlp03.in.ibm.com (9.184.220.128) + by e28smtp06.in.ibm.com (192.168.1.136) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; + Mon, 17 Feb 2014 16:23:50 +0530 +Received: from d28relay01.in.ibm.com (d28relay01.in.ibm.com [9.184.220.58]) + by d28dlp03.in.ibm.com (Postfix) with ESMTP id 80C82125805C; + Mon, 17 Feb 2014 16:25:47 +0530 (IST) +Received: from d28av03.in.ibm.com (d28av03.in.ibm.com [9.184.220.65]) + by d28relay01.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id s1HArhEA64749632; + Mon, 17 Feb 2014 16:23:44 +0530 +Received: from d28av03.in.ibm.com (localhost [127.0.0.1]) + by d28av03.in.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id s1HArkHs009945; + Mon, 17 Feb 2014 16:23:47 +0530 +Received: from srivatsabhat.in.ibm.com ([9.79.254.57]) + by d28av03.in.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id s1HAriQk009844; + Mon, 17 Feb 2014 16:23:45 +0530 +From: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com> +Subject: [PATCH] cpufreq, + powernow-k8: Initialize per-cpu data-structures properly +To: pierre-list@ossman.eu, rjw@rjwysocki.net +Cc: viresh.kumar@linaro.org, linux-pm@vger.kernel.org, + linux-kernel@vger.kernel.org, + "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com> +Date: Mon, 17 Feb 2014 16:18:21 +0530 +Message-ID: <20140217104821.21147.71463.stgit@srivatsabhat.in.ibm.com> +User-Agent: StGIT/0.14.3 +MIME-Version: 1.0 +Content-Type: text/plain; charset="utf-8" +Content-Transfer-Encoding: 7bit +X-TM-AS-MML: disable +X-Content-Scanned: Fidelis XPS MAILER +x-cbid: 14021710-9574-0000-0000-00000BFDA307 +Sender: linux-kernel-owner@vger.kernel.org +Precedence: bulk +List-ID: <linux-kernel.vger.kernel.org> +X-Mailing-List: linux-kernel@vger.kernel.org + +The powernow-k8 driver maintains a per-cpu data-structure called powernow_data +that is used to perform the frequency transitions. It initializes this data- +structure only for the policy->cpu. So, accesses to this data-structure by +other CPUs results in various problems because they would have been +uninitialized. + +Specifically, if a cpu (!= policy->cpu) invokes the drivers' ->get() function, +it returns 0 as the KHz value, since its per-cpu memory doesn't point to +anything valid. This causes problems during suspend/resume since +cpufreq_update_policy() tries to enforce this (0 KHz) as the current frequency +of the CPU, and this madness gets propagated to adjust_jiffies() as well. +Eventually, lots of things start breaking down, including the r8169 ethernet +card, in one particularly interesting case reported by Pierre Ossman. + +https://bugzilla.kernel.org/show_bug.cgi?id=70311 + +Fix this by initializing the per-cpu data-structures of _all_ the CPUs +in the policy appropriately. + +Cc: stable@vger.kernel.org +Reported-by: Pierre Ossman <pierre@ossman.eu> +Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> +--- + + drivers/cpufreq/powernow-k8.c | 10 +++++++--- + 1 file changed, 7 insertions(+), 3 deletions(-) + +diff --git a/drivers/cpufreq/powernow-k8.c b/drivers/cpufreq/powernow-k8.c +index e10b646..6684e03 100644 +--- a/drivers/cpufreq/powernow-k8.c ++++ b/drivers/cpufreq/powernow-k8.c +@@ -1076,7 +1076,7 @@ static int powernowk8_cpu_init(struct cpufreq_policy *pol) + { + struct powernow_k8_data *data; + struct init_on_cpu init_on_cpu; +- int rc; ++ int rc, cpu; + + smp_call_function_single(pol->cpu, check_supported_cpu, &rc, 1); + if (rc) +@@ -1140,7 +1140,9 @@ static int powernowk8_cpu_init(struct cpufreq_policy *pol) + pr_debug("cpu_init done, current fid 0x%x, vid 0x%x\n", + data->currfid, data->currvid); + +- per_cpu(powernow_data, pol->cpu) = data; ++ /* Point all the CPUs in this policy to the same data */ ++ for_each_cpu(cpu, pol->cpus) ++ per_cpu(powernow_data, cpu) = data; + + return 0; + +@@ -1155,6 +1157,7 @@ err_out: + static int powernowk8_cpu_exit(struct cpufreq_policy *pol) + { + struct powernow_k8_data *data = per_cpu(powernow_data, pol->cpu); ++ int cpu; + + if (!data) + return -EINVAL; +@@ -1165,7 +1168,8 @@ static int powernowk8_cpu_exit(struct cpufreq_policy *pol) + + kfree(data->powernow_table); + kfree(data); +- per_cpu(powernow_data, pol->cpu) = NULL; ++ for_each_cpu(cpu, pol->cpus) ++ per_cpu(powernow_data, cpu) = NULL; + + return 0; + } + +-- +To unsubscribe from this list: send the line "unsubscribe linux-kernel" in +the body of a message to majordomo@vger.kernel.org +More majordomo info at http://vger.kernel.org/majordomo-info.html +Please read the FAQ at http://www.tux.org/lkml/ |