ARM fix for v6.9

- clear stale KASan stack poison when a CPU resumes
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rmk/linux

Pull ARM fix from Russell King:

 - clear stale KASan stack poison when a CPU resumes

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rmk/linux:
  ARM: 9381/1: kasan: clear stale stack poison

arch/arm/kernel/sleep.S

@@ -127,6 +127,10 @@ cpu_resume_after_mmu:
 	instr_sync
 #endif
 	bl	cpu_init		@ restore the und/abt/irq banked regs
+#if defined(CONFIG_KASAN) && defined(CONFIG_KASAN_STACK)
+	mov	r0, sp
+	bl	kasan_unpoison_task_stack_below
+#endif
 	mov	r0, #0			@ return zero on success
 	ldmfd	sp!, {r4 - r11, pc}
 ENDPROC(cpu_resume_after_mmu)