POWER9 crash due to STRICT_KERNEL_RWX (WAS: Re: Linux-next POWER9 NULL pointer NIP...)

[Naveen N. Rao]

Hi Qian,

Qian Cai wrote:
> OK, reverted the commit,
> 
> c55d7b5e6426 (“powerpc: Remove STRICT_KERNEL_RWX incompatibility with RELOCATABLE”)
> 
> or set STRICT_KERNEL_RWX=n fixed the crash below and also mentioned in this thread,
> 
> https://lore.kernel.org/lkml/15AC5B0E-A221-4B8C-9039-FA96B8EF7C88@lca.pw/

Do you see any errors logged in dmesg when you see the crash?  
STRICT_KERNEL_RWX changes how patch_instruction() works, so it would be 
interesting to see if there are any ftrace-related errors thrown before 
the crash.


- Naveen