From 1ca04a4ce0d5131471c5a1fac76899dc2d9d3f36 Mon Sep 17 00:00:00 2001 From: Rob Gardner Date: Mon, 21 Dec 2015 21:48:03 -0700 Subject: [PATCH] sparc64: Don't set %pil in rtrap_nmi too early Commit 28a1f53 delays setting %pil to avoid potential hardirq stack overflow in the common rtrap_irq path. Setting %pil also needs to be delayed in the rtrap_nmi path for the same reason. Signed-off-by: Rob Gardner Signed-off-by: Dave Aldridge Signed-off-by: David S. Miller --- arch/sparc/kernel/rtrap_64.S | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/sparc/kernel/rtrap_64.S b/arch/sparc/kernel/rtrap_64.S index 39f0c662f4c8..d08bdaffdbfc 100644 --- a/arch/sparc/kernel/rtrap_64.S +++ b/arch/sparc/kernel/rtrap_64.S @@ -73,7 +73,13 @@ rtrap_nmi: ldx [%sp + PTREGS_OFF + PT_V9_TSTATE], %l1 andn %l1, %l4, %l1 srl %l4, 20, %l4 ba,pt %xcc, rtrap_no_irq_enable - wrpr %l4, %pil + nop + /* Do not actually set the %pil here. We will do that + * below after we clear PSTATE_IE in the %pstate register. + * If we re-enable interrupts here, we can recurse down + * the hardirq stack potentially endlessly, causing a + * stack overflow. + */ .align 64 .globl rtrap_irq, rtrap, irqsz_patchme, rtrap_xcall -- 2.20.1