Merge branch 'x86/debug' into x86/irq

We merge this branch because x86/debug touches code that we started
cleaning up in x86/irq. The two branches started out independent,
but as unexpected amount of activity went into x86/irq, they became
dependent. Resolve that by this cross-merge.

arch/x86/kernel/entry_32.S

@@ -847,6 +847,7 @@ ENTRY(kernel_thread_helper)
 	push %eax
 	CFI_ADJUST_CFA_OFFSET 4
 	call do_exit
+	ud2			# padding for call trace
 	CFI_ENDPROC
 ENDPROC(kernel_thread_helper)