On Fri, Jan 15, 2021 at 12:51:03PM -0800, Luck, Tony wrote:

 static void kill_me_now(struct callback_head *ch)
 {
+	p->mce_count = 0;
 	force_sig(SIGBUS);
 }

Brown paper bag time ... I just pasted that line from kill_me_maybe()
and I thought I did a re-compile ... but obviously not since it gives

error: ‘p’ undeclared (first use in this function)

Option a) (just like kill_me_maybe)

struct task_struct *p = container_of(cb, struct task_struct, mce_kill_me);

Option b) (simpler ... not sure why PeterZ did the container_of thing

	current->mce_count = 0;

-Tony