Re: [PATCH v4 9/9] riscv: Fixup lockdep_assert_held(&text_mutex) in patch_insn_write

From: Steven Rostedt
Date: Tue Oct 20 2020 - 16:41:28 EST


On Tue, 20 Oct 2020 19:18:01 +0800
Guo Ren <guoren@xxxxxxxxxx> wrote:

> > What platform are you testing ? We are seeing a crash while enabling
> > any of the tracers multiple times
> > on Qemu/HiFive Unleashed.
> I use qemu for testing. I've changed dynamic ftrace mechanism from
> mcount to -fpatchable-entry.
>
> The problem is made by the lockdep checking of text_mutex.

If you are switching to "patchable-entry" you shouldn't need to use
stop_machine for the updates. No?

-- Steve