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* [BUG] warning at kernel/cpu.c:38/lock_cpu_hotplug()
@ 2006-09-22 22:45 S.Çağlar Onur
  2006-09-22 23:05 ` Dave Jones
  2006-09-22 23:13 ` Dave Jones
  0 siblings, 2 replies; 6+ messages in thread
From: S.Çağlar Onur @ 2006-09-22 22:45 UTC (permalink / raw)
  To: linux-kernel

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Hi;

With kernel-2.6.18, "modprobe cpufreq_stats" always (i can reproduce) gaves 
following;

...
Lukewarm IQ detected in hotplug locking
BUG: warning at kernel/cpu.c:38/lock_cpu_hotplug()
 [<b0134a42>] lock_cpu_hotplug+0x42/0x65
 [<b02f8af1>] cpufreq_update_policy+0x25/0xad
 [<b0358756>] kprobe_flush_task+0x18/0x40
 [<b0355aab>] schedule+0x63f/0x68b
 [<b01377c2>] __link_module+0x0/0x1f
 [<b0119e7d>] __cond_resched+0x16/0x34
 [<b03560bf>] cond_resched+0x26/0x31
 [<b0355b0e>] wait_for_completion+0x17/0xb1
 [<f965c547>] cpufreq_stat_cpu_callback+0x13/0x20 [cpufreq_stats]
 [<f9670074>] cpufreq_stats_init+0x74/0x8b [cpufreq_stats]
 [<b0137872>] sys_init_module+0x91/0x174
 [<b0102c81>] sysenter_past_esp+0x56/0x79

on 

zangetsu ~ # cat /proc/cpuinfo
processor       : 0
vendor_id       : GenuineIntel
cpu family      : 6
model           : 13
model name      : Intel(R) Pentium(R) M processor 1.73GHz
stepping        : 8
cpu MHz         : 1733.000
cache size      : 2048 KB
fdiv_bug        : no
hlt_bug         : no
f00f_bug        : no
coma_bug        : no
fpu             : yes
fpu_exception   : yes
cpuid level     : 2
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca 
cmov pat clflush dts acpi mmx fxsr sse sse2 ss tm pbe nx up est tm2
bogomips        : 3460.58

If needed i can gave more info/config etc.

Cheers
-- 
S.Çağlar Onur <caglar@pardus.org.tr>
http://cekirdek.pardus.org.tr/~caglar/

Linux is like living in a teepee. No Windows, no Gates and an Apache in house!

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^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [BUG] warning at kernel/cpu.c:38/lock_cpu_hotplug()
  2006-09-22 22:45 [BUG] warning at kernel/cpu.c:38/lock_cpu_hotplug() S.Çağlar Onur
@ 2006-09-22 23:05 ` Dave Jones
  2006-09-22 23:13 ` Dave Jones
  1 sibling, 0 replies; 6+ messages in thread
From: Dave Jones @ 2006-09-22 23:05 UTC (permalink / raw)
  To: S.Çağlar Onur; +Cc: linux-kernel

On Sat, Sep 23, 2006 at 01:45:16AM +0300, S.Çağlar Onur wrote:
 > Hi;
 > 
 > With kernel-2.6.18, "modprobe cpufreq_stats" always (i can reproduce) gaves 
 > following;
 > 
 > ...
 > Lukewarm IQ detected in hotplug locking
 > BUG: warning at kernel/cpu.c:38/lock_cpu_hotplug()
 >  [<b0134a42>] lock_cpu_hotplug+0x42/0x65
 >  [<b02f8af1>] cpufreq_update_policy+0x25/0xad
 >  [<b0358756>] kprobe_flush_task+0x18/0x40
 >  [<b0355aab>] schedule+0x63f/0x68b
 >  [<b01377c2>] __link_module+0x0/0x1f
 >  [<b0119e7d>] __cond_resched+0x16/0x34
 >  [<b03560bf>] cond_resched+0x26/0x31
 >  [<b0355b0e>] wait_for_completion+0x17/0xb1
 >  [<f965c547>] cpufreq_stat_cpu_callback+0x13/0x20 [cpufreq_stats]
 >  [<f9670074>] cpufreq_stats_init+0x74/0x8b [cpufreq_stats]
 >  [<b0137872>] sys_init_module+0x91/0x174
 >  [<b0102c81>] sysenter_past_esp+0x56/0x79

Ah yes, cpufreq vs hotplug cpu locking. The eternal battle continues.

Andrew, did we arrive at concensus about how we should fix this?
I'm still of the opinion that it should be ripped out
completely, and started from scratch.

	Dave


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [BUG] warning at kernel/cpu.c:38/lock_cpu_hotplug()
  2006-09-22 22:45 [BUG] warning at kernel/cpu.c:38/lock_cpu_hotplug() S.Çağlar Onur
  2006-09-22 23:05 ` Dave Jones
@ 2006-09-22 23:13 ` Dave Jones
  2006-09-23  9:36   ` S.Çağlar Onur
  2006-09-23  9:42   ` S.Çağlar Onur
  1 sibling, 2 replies; 6+ messages in thread
From: Dave Jones @ 2006-09-22 23:13 UTC (permalink / raw)
  To: S.Çağlar Onur; +Cc: linux-kernel

On Sat, Sep 23, 2006 at 01:45:16AM +0300, S.Çağlar Onur wrote:
 > Hi;
 > 
 > With kernel-2.6.18, "modprobe cpufreq_stats" always (i can reproduce) gaves 
 > following;
 > 
 > ...
 > Lukewarm IQ detected in hotplug locking
 > BUG: warning at kernel/cpu.c:38/lock_cpu_hotplug()
 >  [<b0134a42>] lock_cpu_hotplug+0x42/0x65
 >  [<b02f8af1>] cpufreq_update_policy+0x25/0xad
 >  [<b0358756>] kprobe_flush_task+0x18/0x40
 >  [<b0355aab>] schedule+0x63f/0x68b
 >  [<b01377c2>] __link_module+0x0/0x1f
 >  [<b0119e7d>] __cond_resched+0x16/0x34
 >  [<b03560bf>] cond_resched+0x26/0x31
 >  [<b0355b0e>] wait_for_completion+0x17/0xb1
 >  [<f965c547>] cpufreq_stat_cpu_callback+0x13/0x20 [cpufreq_stats]
 >  [<f9670074>] cpufreq_stats_init+0x74/0x8b [cpufreq_stats]
 >  [<b0137872>] sys_init_module+0x91/0x174
 >  [<b0102c81>] sysenter_past_esp+0x56/0x79

This should do the trick.
I'll merge the same patch into cpufreq.git

		Dave

--- linux-2.6.18.noarch/drivers/cpufreq/cpufreq_stats.c~	2006-09-22 19:12:57.000000000 -0400
+++ linux-2.6.18.noarch/drivers/cpufreq/cpufreq_stats.c	2006-09-22 19:13:03.000000000 -0400
@@ -350,12 +350,10 @@ __init cpufreq_stats_init(void)
 	}
 
 	register_hotcpu_notifier(&cpufreq_stat_cpu_notifier);
-	lock_cpu_hotplug();
 	for_each_online_cpu(cpu) {
 		cpufreq_stat_cpu_callback(&cpufreq_stat_cpu_notifier, CPU_ONLINE,
 			(void *)(long)cpu);
 	}
-	unlock_cpu_hotplug();
 	return 0;
 }
 static void

-- 
http://www.codemonkey.org.uk

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [BUG] warning at kernel/cpu.c:38/lock_cpu_hotplug()
  2006-09-22 23:13 ` Dave Jones
@ 2006-09-23  9:36   ` S.Çağlar Onur
  2006-09-23 18:10     ` Dave Jones
  2006-09-23  9:42   ` S.Çağlar Onur
  1 sibling, 1 reply; 6+ messages in thread
From: S.Çağlar Onur @ 2006-09-23  9:36 UTC (permalink / raw)
  To: Dave Jones; +Cc: linux-kernel

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23 Eyl 2006 Cts 02:13 tarihinde, Dave Jones şunları yazmıştı: 
> On Sat, Sep 23, 2006 at 01:45:16AM +0300, S.Çağlar Onur wrote:
>  > Hi;
>  >
>  > With kernel-2.6.18, "modprobe cpufreq_stats" always (i can reproduce)
>  > gaves following;
>  >
>  > ...
>  > Lukewarm IQ detected in hotplug locking
>  > BUG: warning at kernel/cpu.c:38/lock_cpu_hotplug()
>  >  [<b0134a42>] lock_cpu_hotplug+0x42/0x65
>  >  [<b02f8af1>] cpufreq_update_policy+0x25/0xad
>  >  [<b0358756>] kprobe_flush_task+0x18/0x40
>  >  [<b0355aab>] schedule+0x63f/0x68b
>  >  [<b01377c2>] __link_module+0x0/0x1f
>  >  [<b0119e7d>] __cond_resched+0x16/0x34
>  >  [<b03560bf>] cond_resched+0x26/0x31
>  >  [<b0355b0e>] wait_for_completion+0x17/0xb1
>  >  [<f965c547>] cpufreq_stat_cpu_callback+0x13/0x20 [cpufreq_stats]
>  >  [<f9670074>] cpufreq_stats_init+0x74/0x8b [cpufreq_stats]
>  >  [<b0137872>] sys_init_module+0x91/0x174
>  >  [<b0102c81>] sysenter_past_esp+0x56/0x79
>
> This should do the trick.
> I'll merge the same patch into cpufreq.git
>
> 		Dave

Ill try

> --- linux-2.6.18.noarch/drivers/cpufreq/cpufreq_stats.c~	2006-09-22
> 19:12:57.000000000 -0400 +++
> linux-2.6.18.noarch/drivers/cpufreq/cpufreq_stats.c	2006-09-22
> 19:13:03.000000000 -0400 @@ -350,12 +350,10 @@ __init
> cpufreq_stats_init(void)
>  	}
>
>  	register_hotcpu_notifier(&cpufreq_stat_cpu_notifier);
> -	lock_cpu_hotplug();
>  	for_each_online_cpu(cpu) {
>  		cpufreq_stat_cpu_callback(&cpufreq_stat_cpu_notifier, CPU_ONLINE,
>  			(void *)(long)cpu);
>  	}
> -	unlock_cpu_hotplug();
>  	return 0;
>  }
>  static void

What about cpufreq_stats_exit, it has same locking? Seems like rmmod may cause 
same problem or im totaly wrong?

Cheer
-- 
S.Çağlar Onur <caglar@pardus.org.tr>
http://cekirdek.pardus.org.tr/~caglar/

Linux is like living in a teepee. No Windows, no Gates and an Apache in house!

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^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [BUG] warning at kernel/cpu.c:38/lock_cpu_hotplug()
  2006-09-22 23:13 ` Dave Jones
  2006-09-23  9:36   ` S.Çağlar Onur
@ 2006-09-23  9:42   ` S.Çağlar Onur
  1 sibling, 0 replies; 6+ messages in thread
From: S.Çağlar Onur @ 2006-09-23  9:42 UTC (permalink / raw)
  To: Dave Jones; +Cc: linux-kernel

[-- Attachment #1: Type: text/plain, Size: 352 bytes --]

23 Eyl 2006 Cts 02:13 tarihinde, Dave Jones şunları yazmıştı: 
> This should do the trick.
> I'll merge the same patch into cpufreq.git

Yep, it solved the problem 

Cheers
-- 
S.Çağlar Onur <caglar@pardus.org.tr>
http://cekirdek.pardus.org.tr/~caglar/

Linux is like living in a teepee. No Windows, no Gates and an Apache in house!

[-- Attachment #2: Type: application/pgp-signature, Size: 189 bytes --]

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [BUG] warning at kernel/cpu.c:38/lock_cpu_hotplug()
  2006-09-23  9:36   ` S.Çağlar Onur
@ 2006-09-23 18:10     ` Dave Jones
  0 siblings, 0 replies; 6+ messages in thread
From: Dave Jones @ 2006-09-23 18:10 UTC (permalink / raw)
  To: S.Çağlar Onur; +Cc: linux-kernel

On Sat, Sep 23, 2006 at 12:36:34PM +0300, S.Çağlar Onur wrote:
 > 23 Eyl 2006 Cts 02:13 tarihinde, Dave Jones şunları yazmıştı: 
 > > On Sat, Sep 23, 2006 at 01:45:16AM +0300, S.Çağlar Onur wrote:
 > >  > Hi;
 > >  >
 > >  > With kernel-2.6.18, "modprobe cpufreq_stats" always (i can reproduce)
 > >  > gaves following;
 > >  >
 > >  > ...
 > >  > Lukewarm IQ detected in hotplug locking
 > >  > BUG: warning at kernel/cpu.c:38/lock_cpu_hotplug()
 > >  >  [<b0134a42>] lock_cpu_hotplug+0x42/0x65
 > >  >  [<b02f8af1>] cpufreq_update_policy+0x25/0xad
 > >  >  [<b0358756>] kprobe_flush_task+0x18/0x40
 > >  >  [<b0355aab>] schedule+0x63f/0x68b
 > >  >  [<b01377c2>] __link_module+0x0/0x1f
 > >  >  [<b0119e7d>] __cond_resched+0x16/0x34
 > >  >  [<b03560bf>] cond_resched+0x26/0x31
 > >  >  [<b0355b0e>] wait_for_completion+0x17/0xb1
 > >  >  [<f965c547>] cpufreq_stat_cpu_callback+0x13/0x20 [cpufreq_stats]
 > >  >  [<f9670074>] cpufreq_stats_init+0x74/0x8b [cpufreq_stats]
 > >  >  [<b0137872>] sys_init_module+0x91/0x174
 > >  >  [<b0102c81>] sysenter_past_esp+0x56/0x79
 > >
 > > This should do the trick.
 > > I'll merge the same patch into cpufreq.git
 > 
 > What about cpufreq_stats_exit, it has same locking? Seems like rmmod may cause 
 > same problem or im totaly wrong?

The CPU_DEAD notifier doesn't take the lock, so it's safe.

	Dave

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2006-09-23 18:11 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2006-09-22 22:45 [BUG] warning at kernel/cpu.c:38/lock_cpu_hotplug() S.Çağlar Onur
2006-09-22 23:05 ` Dave Jones
2006-09-22 23:13 ` Dave Jones
2006-09-23  9:36   ` S.Çağlar Onur
2006-09-23 18:10     ` Dave Jones
2006-09-23  9:42   ` S.Çağlar Onur

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