Re: Bisecting tip/auto-x86-next?

["Yinghai Lu" <yhlu.kernel@gmail.com>]

On Sat, Jun 21, 2008 at 3:23 AM, Kevin Winchester
<kjwinchester@gmail.com> wrote:
> On Sat, Jun 21, 2008 at 7:18 AM, Yinghai Lu <yhlu.kernel@gmail.com> wrote:
>> On Sat, Jun 21, 2008 at 3:00 AM, Kevin Winchester
>> <kjwinchester@gmail.com> wrote:
>>> Yinghai Lu wrote:
>>>>
>>>> On Fri, Jun 20, 2008 at 5:00 PM, Kevin Winchester
>>>> <kjwinchester@gmail.com> wrote:
>>>>>
>>>>> Ingo Molnar wrote:
>>>>>>
>>>>>> * Kevin Winchester <kjwinchester@gmail.com> wrote:
>>>>>>
>>>>>>>> hm, could you send me the config that triggered this?
>>>>>>>
>>>>>>> I will do so tonight when I am home again.  It is a UP AMD64 box with a
>>>>>>> VIA chipset, if that helps.
>>>>>>>
>>>>>>>> btw., you can probably ignore this one safely. Also please tell me at
>>>>>>>> which commit ID you were at when you triggered this warning.
>>>>>>>
>>>>>>> Good to know - I will get the commit ID tonight as well, although
>>>>>>> wouldn't following the same bisection sequence that I did give you the
>>>>>>> same
>>>>>>> bisection point?  I guess that would assume that linus/master and
>>>>>>> auto-x86-next haven't changed much since last night, which might not be
>>>>>>> correct.
>>>>>>
>>>>>> yeah, you'd probably not hit that warning with the x86/gart bisection
>>>>>> sequence. (Assuming the bug is introduced in that branch - so you should
>>>>>> first check whether pure x86/gart kernel triggers the problem too.)
>>>>>>
>>>>>> If you still have the commit ID around then please send it - if you
>>>>>> dont,
>>>>>> no problem, it's no big issue. I wanted to check how wide the bisection
>>>>>> window is where the warning triggers.
>>>>>>
>>>>> I'm sorry - I accidentally checkout out x86/gart to test it before
>>>>> grabbing
>>>>> the commit ID.
>>>>>
>>>>> I went ahead with the bisection and found:
>>>>>
>>>>>
>>>>>
>>>>> 8c9fd91a0dc503f085169d44f4360be025f75224 is first bad commit
>>>>> commit 8c9fd91a0dc503f085169d44f4360be025f75224
>>>>> Author: Yinghai Lu <yhlu.kernel@gmail.com>
>>>>> Date:   Sun Apr 13 18:42:31 2008 -0700
>>>>>
>>>>>   x86: checking aperture size order
>>>>>
>>>>>   some systems are using 32M for gart and agp when memory is less than
>>>>> 4G.
>>>>>   Kernel will reject and try to allcate another 64M that is not needed,
>>>>>   and we will waste 64M of perfectly good RAM.
>>>>>
>>>>>   this patch adds a workaround by checking aper_base/order between NB and
>>>>>   agp bridge. If they are the same, and memory size is less than 4G, it
>>>>>   will allow it.
>>>>>
>>>>>   Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
>>>>>   Signed-off-by: Ingo Molnar <mingo@elte.hu>
>>>>>   Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
>>>>>
>>>>> :040000 040000 848d6e4045a14d01fc0a794d4350d8a84f3ceff6
>>>>> 4a10a52b41309060cd5dc1bf0c322f6d43b2477b M      arch
>>>>> :040000 040000 aa1cee87b1f5b1b30ed03ce6164ad7f404fef2a3
>>>>> f9ce0aaa1f7d4fdc7bdc5a43285495db53a6f531 M      drivers
>>>>>
>>>>>
>>>>> as the first bad commit.  I do not have time to look at the patch right
>>>>> now,
>>>>> but in case anyone else does, I figured I would post it.
>>>>>
>>>>
>>>> please send out whole boot logs with "debug" in command line.
>>>>
>>>
>>> "debug" in the command line doesn't seem to have any effect on the printout
>>> (is there some config option I need to use with it?), but here it is anyway:
>>
>> are you using tip/master?
>>
>> http://people.redhat.com/mingo/sched-devel.git/README
>>
>
> That log is from tip/x86/gart, which is where the problem patch was
> bisected.  Would you get better debugging info from tip/master (which
> includes tip/x86/gart, I believe, and thus would show the problem as
> well)?

tip/master doesn't work?

YH