ppc64le STRICT_MODULE_RWX and livepatch apply_relocate_add() crashes

[Christophe Leroy]

Le 01/11/2021 à 14:48, Joe Lawrence a écrit :
> On 11/1/21 5:20 AM, Russell Currey wrote:
>> I'm looking into this now, will update when there's progress.  I
>> personally wasn't aware but Jordan flagged this as an issue back in
>> August [0].  Are the selftests in the klp-convert tree sufficient for
>> testing?  I'm not especially familiar with livepatching & haven't used
>> the userspace tools.
>>
> 
> Hi Russell, thanks for taking a look.
> 
> Testing with that klp-convert tree is probably the quickest and easiest
> way to verify the late relocations.
> 
> I'm happy to setup and test additional tools (ie, kpatch-build) with any
> potential changes as I know they take longer to config and run.
> 

Hello Joe,

I'm implementing LIVEPATCH on PPC32 and I wanted to test with 
STRICT_MODULE_RWX enabled so I took your branch as suggested, but I'm 
getting the following errors on build. What shall I do ?

   CALL    scripts/checksyscalls.sh
   CALL    scripts/atomic/check-atomics.sh
   CHK     include/generated/compile.h
   KLP     lib/livepatch/test_klp_convert1.ko
klp-convert: section .rela.klp.module_relocs.test_klp_convert_mod length 
beyond nr_entries

klp-convert: Unable to load user-provided sympos
make[2]: *** [scripts/Makefile.modfinal:79: 
lib/livepatch/test_klp_convert1.ko] Error 255
   KLP     lib/livepatch/test_klp_convert2.ko
klp-convert: section .rela.klp.module_relocs.test_klp_convert_mod length 
beyond nr_entries

klp-convert: Unable to load user-provided sympos
make[2]: *** [scripts/Makefile.modfinal:79: 
lib/livepatch/test_klp_convert2.ko] Error 255
   KLP     lib/livepatch/test_klp_convert_sections.ko
klp-convert: section .rela.klp.module_relocs.test_klp_convert_mod length 
beyond nr_entries

klp-convert: Unable to load user-provided sympos
make[2]: *** [scripts/Makefile.modfinal:79: 
lib/livepatch/test_klp_convert_sections.ko] Error 255
make[2]: Target '__modfinal' not remade because of errors.
make[1]: *** [scripts/Makefile.modpost:145: __modpost] Error 2
make: *** [Makefile:1770: modules] Error 2

Christophe