Subject: [PATCH 1/3] powerpc: kdump: Fix NULL pointer dereference in irq disable code

From: Anton Blanchard <[email-masked]>
Date: Tue, 11 May 2010 12:23:29 +1000

With sparse irqs we have to check if we have a descriptor before dereferencing
it.

Signed-off-by: Anton Blanchard <[email-masked]>
---

diff --git a/arch/powerpc/kernel/crash.c b/arch/powerpc/kernel/crash.c
index 6f4613d..5182439 100644
--- a/arch/powerpc/kernel/crash.c
+++ b/arch/powerpc/kernel/crash.c
@@ -375,6 +375,9 @@ void default_machine_crash_shutdown(struct pt_regs *regs)
 	for_each_irq(i) {
 		struct irq_desc *desc = irq_to_desc(i);
 
+		if (!desc)
+			continue;
+
 		if (desc->status & IRQ_INPROGRESS)
 			desc->chip->eoi(i);