[PATCH] tracing: Fix tracing_marker may trigger page fault during preempt_disable

[Steven Rostedt]

On Tue, 2 Sep 2025 11:47:32 +0800
Luo Gengkun <luogengkun at huaweicloud.com> wrote:

> > If this does not check the preempt flag, it is a problem.
> > Maybe arm64 needs to do fixup and abort instead of do_mem_abort()?  
> 
> My kernel was built without CONFIG_PREEMPT_COUNT, so the preempt_disable()
> does nothing more than act as a barrier. In this case, it can pass the
> check by schedule(). Perhaps this is another issue?

This is why I never triggered it. I always have PREEMPT_COUNT enabled.
I have tests that test without it, but I don't think those tests access
trace_marker, and if they do, they don't stress it.

-- Steve