[PATCH] powerpc/pseries/mce: Avoid instrumentation in realmode

[Sachin Sant]

> On 29-Aug-2022, at 5:02 PM, Sachin Sant <sachinp at linux.ibm.com> wrote:
> 
> 
> 
>> On 29-Aug-2022, at 1:15 PM, Ganesh Goudar <ganeshgr at linux.ibm.com> wrote:
>> 
>> Part of machine check error handling is done in realmode,
>> As of now instrumentation is not possible for any code that
>> runs in realmode.
>> When MCE is injected on KASAN enabled kernel, crash is
>> observed, Hence force inline or mark no instrumentation
>> for functions which can run in realmode to avoid KASAN
>> instrumentation.
>> 
>> Signed-off-by: Ganesh Goudar <ganeshgr at linux.ibm.com>
>> ---
>> arch/powerpc/include/asm/interrupt.h | 2 +-
>> arch/powerpc/include/asm/rtas.h      | 4 ++--
>> arch/powerpc/kernel/rtas.c           | 4 ++--
>> 3 files changed, 5 insertions(+), 5 deletions(-)
> 
> Thanks for the patch. I tested it on top of 6.0.0-rc3. It proceeds further but
> eventually crashes after arch_local_save_flags
> 

Seems like following functions also should be marked as __always_inline

arch_local_save_flags
irq_soft_mask_return
irq_soft_mask_set_return
irq_soft_mask_set

With these additional changes the test successfully runs to completion.

- Sachin