Re: [PATCH v2] PowerPC: kernel: compiling issue, make additionalroom in exception vector area

From: Chen Gang F T
Date: Sat Apr 27 2013 - 05:30:16 EST

On 2013å04æ26æ 11:54, Mike Qiu wrote:
> ä 2013/4/26 11:42, Chen Gang åé:
>> On 2013å04æ26æ 11:25, Chen Gang wrote:
>>> On 2013å04æ26æ 11:08, Mike Qiu wrote:
>>>> ä 2013/4/26 10:06, Chen Gang åé:
>>>>> On 2013å04æ26æ 10:03, Mike Qiu wrote:
>>>>>> ïï 2013/4/26 9:36, Chen Gang Ðïï:
>>>>>>>> On 2013ïï04ïï26ïï 09:18, Chen Gang wrote:
>>>>>>>>>> On 2013ïï04ïï26ïï 09:06, Chen Gang wrote:
>>>>>>>>>>>>>> CFAR is the Come From Register. It saves the location of the
>>>>>>>>>>>>>> last
>>>>>>>>>>>>>>>> branch and is hence overwritten by any branch.
>>>>>>>>>>>> Do we process it just like others done (e.g. 0x300, 0xe00,
>>>>>>>>>>>> 0xe20 ...) ?
>>>>>>>>>>>> . = 0x900
>>>>>>>>>>>> .globl decrementer_pSeries
>>>>>>>>>>>> decrementer_pSeries:
>>>>>>>>>>>> SET_SCRATCH0(r13)
>>>>>>>>>>>> b decrementer_pSeries_0
>>>>>>>>>>>> ...
>>>>>>>> Oh, it seems EXCEPTION_PROLOG_1 will save the regesters which
>>>>>>>> related
>>>>>>>> with CFAR, so I think need move EXCEPTION_PROLOG_1 to near 0x900.
>>>>>> I will try your diff V2, to see if the machine can boot up
>>>>> OK, thanks. (hope it can work)
>>>> It seems that the machine can be bootup in powernv mode, but I'm not
>>>> sure if my machine call that module.
>>>> At lease my machine can boot up
>> Please reference commit number: 1707dd161349e6c54170c88d94fed012e3d224e3
>> (1707dd1 powerpc: Save CFAR before branching in interrupt entry paths)
>> What our diff v2 has done is just the fix for our patch v2 (just like
>> the commit 1707dd1 has done).
>> Please check, thanks.
>> :-)
> I will check this evening or tomorrow, I have something else to do this
> afteroon.

I think the diff v2 is correct, but is not the best one for this issue.

I prefer the Paul's patch for this issue which has better performance



Chen Gang

Flying Transformer
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at