Re: applesmc oops in 3.10/3.11

From: Chris Murphy <bugzilla@colorremedies.com>
To: Guenter Roeck <linux@roeck-us.net>
Cc: Henrik Rydberg <rydberg@euromail.se>,
	Josh Boyer <jwboyer@fedoraproject.org>,
	khali@linux-fr.org, lm-sensors@lm-sensors.org,
	"Linux-Kernel@Vger. Kernel. Org" <linux-kernel@vger.kernel.org>
Subject: Re: applesmc oops in 3.10/3.11
Date: Tue, 1 Oct 2013 21:55:45 -0600	[thread overview]
Message-ID: <CAFC20BD-C5B7-4705-932E-930501159502@colorremedies.com> (raw)
In-Reply-To: <20131002035156.GA566@roeck-us.net>

On Oct 1, 2013, at 9:51 PM, Guenter Roeck <linux@roeck-us.net> wrote:

> On Tue, Oct 01, 2013 at 07:09:26PM -0600, Chris Murphy wrote:
>> 
>> On Oct 1, 2013, at 10:24 AM, Guenter Roeck <linux@roeck-us.net> wrote:
>> 
>>> On Tue, Oct 01, 2013 at 09:33:13AM -0600, Chris Murphy wrote:
>>>> 
>>>> On Oct 1, 2013, at 9:19 AM, Guenter Roeck <linux@roeck-us.net> wrote:
>>>> 
>>>>> On Tue, Oct 01, 2013 at 12:55:26PM +0200, Henrik Rydberg wrote:
>>>>>>>> Warning message triggered with 3.12.0-0.rc3.git0.1.fc21.x86_64.
>>>>>>>> 
>>>>>>>> [   10.886016] applesmc: key count changed from 261 to 1174405121
>>>>>>>> 
>>>>>>> 
>>>>>>> Explains the crash, but the new key count is very wrong. 1174405121 = 0x46000001.
>>>>>>> Which I guess explains the subsequent memory allocation error in the log.
>>>>>>> 
>>>>>>> Henrik, any idea what might be going on ? Is it possible that the previous
>>>>>>> command failure leaves some state machine in a bad state ?
>>>>>> 
>>>>>> I seem to recall a report on another similar state problem on newer
>>>>>> machines, so maybe, yes. Older machines seem fine, I have never
>>>>>> encountered the problem myself. Here is a patch to test that
>>>>>> theory. It has been tested to be pretty harmless on two different
>>>>>> generations.
>>>>>> 
>>>>>> I really really do not want to add an 'if (value is insane)' check ;-)
>>>>>> 
>>>>> Chris,
>>>>> 
>>>>> any chance you can load this patch on an affected machine so we can get
>>>>> test feedback ? This one is too experimental to submit upstream without
>>>>> knowing that it really fixes the problem.
>>>> 
>>>> Yes. What kernel.org source version should I apply it against? I'd use the non-debug config file from an equivalent version Fedora kernel, unless asked otherwise. And also should I test it on other vintages? I have here MBP4,1(2008); MBP8,2(2011), and MBP10,2(2012).
>>>> 
>>> Only requirement is that it also includes the previous patch, so it would be
>>> optimal if you can apply it on top of the previous image.
>> 
>> Patch added on top of 3.12.0-0.rc3.git0.1.fc20.x86_64 and built. But after ~dozen reboots, I'm not triggering the problem. The only items in dmesg with smc in it:
>> 
>> [   13.799819] applesmc: key=261 fan=2 temp=14 index=14 acc=1 lux=2 kbd=1
>> [   13.833402] input: applesmc as /devices/platform/applesmc.768/input/input10
>> 
> 
> Hi Chris,
> 
> That only means that you did not hit the problem. There may be some secondary
> trigger (cold boot ? coffee on the cpu ?).
> 
> One thing I have seen in all logs is the earlier "send_byte fail" message, so
> I think that is a pre-requisite.

I have no idea how to trigger it. I have tried cold and warm boots. Boots between linux and OS X to linux. *shrug* I'll keep trying as I'm doing other testing, maybe I'll stumble onto it.

Chris