From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Fri, 9 Dec 2011 04:06:18 +0000 (+1100)
Subject: powerpc/pmac: Fix SMP kernels on pre-core99 UP machines
X-Git-Tag: firefly_0821_release~7541^2~1551
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=029a9375e40af22c2f75d7a15615d2c87731f366;p=firefly-linux-kernel-4.4.55.git

powerpc/pmac: Fix SMP kernels on pre-core99 UP machines

commit 78c5c68a4cf4329d17abfa469345ddf323d4fd62 upstream.

The code for "powersurge" SMP would kick in and cause a crash
at boot due to the lack of a NULL test.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Jeremy Kerr <jeremy.kerr@canonical.com>
Reported-by: Adam Conrad <adconrad@ubuntu.com>
Tested-by: Adam Conrad <adconrad@ubuntu.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/arch/powerpc/platforms/powermac/smp.c b/arch/powerpc/platforms/powermac/smp.c
index db092d7c4c5b..53a6be7ebe3c 100644
--- a/arch/powerpc/platforms/powermac/smp.c
+++ b/arch/powerpc/platforms/powermac/smp.c
@@ -414,7 +414,7 @@ static struct irqaction psurge_irqaction = {
 
 static void __init smp_psurge_setup_cpu(int cpu_nr)
 {
-	if (cpu_nr != 0)
+	if (cpu_nr != 0 || !psurge_start)
 		return;
 
 	/* reset the entry point so if we get another intr we won't