Hi Steve,
Steven Rostedt wrote:
On Thu, 23 Apr 2020 18:21:14 +0200
Christophe Leroy <christophe.le...@c-s.fr> wrote:
Le 23/04/2020 à 17:09, Naveen N. Rao a écrit :
> With STRICT_KERNEL_RWX, we are currently ignoring return value from
> __patch_instruction() in do_patch_instruction(), resulting in the error
> not being propagated back. Fix the same.
Good patch.
Be aware that there is ongoing work which tend to wanting to replace
error reporting by BUG_ON() . See
https://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=166003
Thanks for the reference. I still believe that WARN_ON() should be used in
99% of the cases, including here. And only do a BUG_ON() when you know
there's no recovering from it.
I'm not sure if you meant that we should have a WARN_ON() in
patch_instruction(), or if it was about the users of
patch_instruction(). As you're well aware, ftrace likes to do its own
WARN_ON() if any of its operations fail through ftrace_bug(). That was
the reason I didn't add anything here.
- Naveen
