RE: WARNING: smp_call_function_single() and smp_call_function_mask()

From: Pallipadi, Venkatesh
Date: Mon Dec 03 2007 - 15:46:19 EST




>-----Original Message-----
>From: linux-kernel-owner@xxxxxxxxxxxxxxx
>[mailto:linux-kernel-owner@xxxxxxxxxxxxxxx] On Behalf Of Tomas Carnecky
>Sent: Monday, December 03, 2007 12:14 PM
>To: Arjan van de Ven
>Cc: linux-kernel@xxxxxxxxxxxxxxx; lenb@xxxxxxxxxx
>Subject: Re: WARNING: smp_call_function_single() and
>smp_call_function_mask()
>
>Arjan van de Ven wrote:
>> On Sun, 02 Dec 2007 09:43:39 +0100
>> Tomas Carnecky <tom@xxxxxxxxxxxxx> wrote:
>>
>>> WARNING: at arch/x86/kernel/smp_64.c:427 smp_call_function_single()
>>> WARNING: at arch/x86/kernel/smp_64.c:397 smp_call_function_mask()
>>>
>>> dmesg and config attached.
>>>
>>> I'm getting about three of each at boot. I'm running:
>>> commit e1cca7e8d484390169777b423a7fe46c7021fec1
>>> Date: Thu Nov 29 16:25:29 2007 -0800
>>> which is the latest git as of yesterday plus a one (unrelated) debug
>>> statement patch in usb uhci.
>>>
>>> There was a similar bug report after 2.6.23-rc8-mm was released.
>>> Though there seems to be a fundamental problem with how people use
>>> smp_call_function*() [1]. And this can just as well be another
>>> incarnation of it.
>>>
>>> Is that easy enough to fix or do I need to bisect (it
>didn't happen in
>>> 2.6.24-rc3)?
>>>
>>
>> this appears to be a bug in the acpi code, to be exact in
>> processor_throttling.c file, function
>> acpi_processor_set_throttling_ptc(); it disables interrupts and then
>> appears to do a cross-cpu IPI to set the state. Well... we can't do
>> that due to deadlock reasons (you can't do IPI's with
>interrupts off or
>> you can get a very nice deadlock with the cpu that you IPI trying to
>> do the same thing to you).
>>
>
>I updated the kernel today (to 1a2edea9aff48...) and the
>warnings are gone.

Yes. This was reported here earlier and fixed by this patch from Yakui.
http://www.ussg.iu.edu/hypermail/linux/kernel/0711.3/1596.html
which should now be merged upstream.

Thanks,
Venki
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/