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

From: Naveen N. Rao
Date: Fri Apr 17 2020 - 03:01:38 EST


Hi Qian,

Qian Cai wrote:
OK, reverted the commit,

c55d7b5e6426 (âpowerpc: Remove STRICT_KERNEL_RWX incompatibility with RELOCATABLEâ)

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@xxxxxx/

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