lkml.org 
[lkml]   [2019]   [Jul]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [PATCH v3 3/3] powerpc/module64: Use symbolic instructions names.
Date
Christophe Leroy <christophe.leroy@c-s.fr> writes:
> Le 08/07/2019 à 02:56, Michael Ellerman a écrit :
>> Christophe Leroy <christophe.leroy@c-s.fr> writes:
>>> To increase readability/maintainability, replace hard coded
>>> instructions values by symbolic names.
>>>
>>> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
>>> ---
>>> v3: fixed warning by adding () in an 'if' around X | Y (unlike said in v2 history, this change was forgotten in v2)
>>> v2: rearranged comments
>>>
>>> arch/powerpc/kernel/module_64.c | 53 +++++++++++++++++++++++++++--------------
>>> 1 file changed, 35 insertions(+), 18 deletions(-)
>>>
>>> diff --git a/arch/powerpc/kernel/module_64.c b/arch/powerpc/kernel/module_64.c
>>> index c2e1b06253b8..b33a5d5e2d35 100644
>>> --- a/arch/powerpc/kernel/module_64.c
>>> +++ b/arch/powerpc/kernel/module_64.c
>>> @@ -704,18 +711,21 @@ int apply_relocate_add(Elf64_Shdr *sechdrs,
>> ...
>>> /*
>>> * If found, replace it with:
>>> * addis r2, r12, (.TOC.-func)@ha
>>> * addi r2, r12, (.TOC.-func)@l
>>> */
>>> - ((uint32_t *)location)[0] = 0x3c4c0000 + PPC_HA(value);
>>> - ((uint32_t *)location)[1] = 0x38420000 + PPC_LO(value);
>>> + ((uint32_t *)location)[0] = PPC_INST_ADDIS | __PPC_RT(R2) |
>>> + __PPC_RA(R12) | PPC_HA(value);
>>> + ((uint32_t *)location)[1] = PPC_INST_ADDI | __PPC_RT(R2) |
>>> + __PPC_RA(R12) | PPC_LO(value);
>>> break;
>>
>> This was crashing and it's amazing how long you can stare at a
>> disassembly and not see the difference between `r2` and `r12` :)
>
> Argh, yes. I was misleaded by the comment I guess. Sorry for that and
> thanks for fixing.

No worries, yes the comment was the problem. I fixed that as well.

cheers

\
 
 \ /
  Last update: 2019-07-12 09:01    [W:0.047 / U:12.416 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site