[U-Boot] [PATCH RFC] armv7: fixloop: don't fixup if location is NULL

[Albert ARIBAUD <albert.aribaud@free.fr>]

Le 08/01/2011 11:32, Andreas Bie?mann a ?crit :
> Dear Minkyu Kang,
>
> Am 27.12.2010 um 11:27 schrieb Minkyu Kang:
>
>> There is possibility that pointers set to NULL before relocation.
>> In this case, system is hang, because of r0 is invalid location in RAM.
>>
>> Signed-off-by: Minkyu Kang<mk7.kang@samsung.com>
>> ---
>> arch/arm/cpu/armv7/start.S |    3 +++
>> 1 files changed, 3 insertions(+), 0 deletions(-)
>>
>> diff --git a/arch/arm/cpu/armv7/start.S b/arch/arm/cpu/armv7/start.S
>> index 684f2d2..4eeb12a 100644
>> --- a/arch/arm/cpu/armv7/start.S
>> +++ b/arch/arm/cpu/armv7/start.S
>> @@ -195,6 +195,8 @@ copy_loop:
>> 	add	r3, r3, r0		/* r3<- rel dyn end in FLASH */
>> fixloop:
>> 	ldr	r0, [r2]		/* r0<- location to fix up, IN FLASH! */
>> +	cmp	r0, #0
>> +	beq	fixskip
>
> I doubt this is correct. In my investigations for 'NULL fixup' (->  see http://thread.gmane.org/gmane.comp.boot-loaders.u-boot/89864/focus=89906) pointed out that only symbols in 'absolute fixup' loop could be 'NULL' if there is a not aliased/empty weakly linked symbol. I did never see a 'NULL' symbol for 'relative fixup' loop!
>
> Therefore I doubt it is correct to check the location at this place. Can you please give an example?
>
> regards
>
> Andreas Bie?mann

Oops. Thanks Andreas for pointing this out. I second the question.

Amicalement,
-- 
Albert.