diff options
| author | Michael Wang <wangyun@linux.vnet.ibm.com> | 2013-06-05 08:49:37 +0000 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2013-06-05 13:46:54 +0200 |
| commit | 2f7021a815f20f3481c10884fe9735ce2a56db35 (patch) | |
| tree | 16d55dcf56bd83bdaade0387d3e82c9a7468f6cb | |
| parent | 8673b83bf2f013379453b4779047bf3c6ae387e4 (diff) | |
| download | linux-2f7021a815f20f3481c10884fe9735ce2a56db35.tar.bz2 | |
cpufreq: protect 'policy->cpus' from offlining during __gov_queue_work()
Jiri Kosina <jkosina@suse.cz> and Borislav Petkov <bp@alien8.de>
reported the warning:
[ 51.616759] ------------[ cut here ]------------
[ 51.621460] WARNING: at arch/x86/kernel/smp.c:123 native_smp_send_reschedule+0x58/0x60()
[ 51.629638] Modules linked in: ext2 vfat fat loop snd_hda_codec_hdmi usbhid snd_hda_codec_realtek coretemp kvm_intel kvm snd_hda_intel snd_hda_codec crc32_pclmul crc32c_intel ghash_clmulni_intel snd_hwdep snd_pcm aesni_intel sb_edac aes_x86_64 ehci_pci snd_page_alloc glue_helper snd_timer xhci_hcd snd iTCO_wdt iTCO_vendor_support ehci_hcd edac_core lpc_ich acpi_cpufreq lrw gf128mul ablk_helper cryptd mperf usbcore usb_common soundcore mfd_core dcdbas evdev pcspkr processor i2c_i801 button microcode
[ 51.675581] CPU: 0 PID: 244 Comm: kworker/1:1 Tainted: G W 3.10.0-rc1+ #10
[ 51.683407] Hardware name: Dell Inc. Precision T3600/0PTTT9, BIOS A08 01/24/2013
[ 51.690901] Workqueue: events od_dbs_timer
[ 51.695069] 0000000000000009 ffff88043a2f5b68 ffffffff8161441c ffff88043a2f5ba8
[ 51.702602] ffffffff8103e540 0000000000000033 0000000000000001 ffff88043d5f8000
[ 51.710136] 00000000ffff0ce1 0000000000000001 ffff88044fc4fc08 ffff88043a2f5bb8
[ 51.717691] Call Trace:
[ 51.720191] [<ffffffff8161441c>] dump_stack+0x19/0x1b
[ 51.725396] [<ffffffff8103e540>] warn_slowpath_common+0x70/0xa0
[ 51.731473] [<ffffffff8103e58a>] warn_slowpath_null+0x1a/0x20
[ 51.737378] [<ffffffff81025628>] native_smp_send_reschedule+0x58/0x60
[ 51.744013] [<ffffffff81072cfd>] wake_up_nohz_cpu+0x2d/0xa0
[ 51.749745] [<ffffffff8104f6bf>] add_timer_on+0x8f/0x110
[ 51.755214] [<ffffffff8105f6fe>] __queue_delayed_work+0x16e/0x1a0
[ 51.761470] [<ffffffff8105f251>] ? try_to_grab_pending+0xd1/0x1a0
[ 51.767724] [<ffffffff8105f78a>] mod_delayed_work_on+0x5a/0xa0
[ 51.773719] [<ffffffff814f6b5d>] gov_queue_work+0x4d/0xc0
[ 51.779271] [<ffffffff814f60cb>] od_dbs_timer+0xcb/0x170
[ 51.784734] [<ffffffff8105e75d>] process_one_work+0x1fd/0x540
[ 51.790634] [<ffffffff8105e6f2>] ? process_one_work+0x192/0x540
[ 51.796711] [<ffffffff8105ef22>] worker_thread+0x122/0x380
[ 51.802350] [<ffffffff8105ee00>] ? rescuer_thread+0x320/0x320
[ 51.808264] [<ffffffff8106634a>] kthread+0xea/0xf0
[ 51.813200] [<ffffffff81066260>] ? flush_kthread_worker+0x150/0x150
[ 51.819644] [<ffffffff81623d5c>] ret_from_fork+0x7c/0xb0
[ 51.918165] nouveau E[ DRM] GPU lockup - switching to software fbcon
[ 51.930505] [<ffffffff81066260>] ? flush_kthread_worker+0x150/0x150
[ 51.936994] ---[ end trace f419538ada83b5c5 ]---
It was caused by the policy->cpus changed during the process of
__gov_queue_work(), in other word, cpu offline happened.
Use get/put_online_cpus() to prevent the offline from happening while
__gov_queue_work() is running.
[rjw: The problem has been present since recent commit 031299b
(cpufreq: governors: Avoid unnecessary per cpu timer interrupts)]
References: https://lkml.org/lkml/2013/6/5/88
Reported-by: Borislav Petkov <bp@alien8.de>
Reported-and-tested-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| -rw-r--r-- | drivers/cpufreq/cpufreq_governor.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c index 5af40ad82d23..dc9b72e25c1a 100644 --- a/drivers/cpufreq/cpufreq_governor.c +++ b/drivers/cpufreq/cpufreq_governor.c @@ -26,6 +26,7 @@ #include <linux/tick.h> #include <linux/types.h> #include <linux/workqueue.h> +#include <linux/cpu.h> #include "cpufreq_governor.h" @@ -180,8 +181,10 @@ void gov_queue_work(struct dbs_data *dbs_data, struct cpufreq_policy *policy, if (!all_cpus) { __gov_queue_work(smp_processor_id(), dbs_data, delay); } else { + get_online_cpus(); for_each_cpu(i, policy->cpus) __gov_queue_work(i, dbs_data, delay); + put_online_cpus(); } } EXPORT_SYMBOL_GPL(gov_queue_work); |