[PATCH] Protect against NULL pointer deref in phyp-dump code.

[Tony Breeds <tony@bakeyournoodle.com>]

print_dump_header() will be called at least once with a NULL pointer in
a normal boot sequence.  if DEBUG is defined then we will get a deref,
add a quick fix to exit early in the NULL pointer case.

Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
---
 arch/powerpc/platforms/pseries/phyp_dump.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/phyp_dump.c b/arch/powerpc/platforms/pseries/phyp_dump.c
index edbc012..16e659a 100644
--- a/arch/powerpc/platforms/pseries/phyp_dump.c
+++ b/arch/powerpc/platforms/pseries/phyp_dump.c
@@ -130,6 +130,9 @@ static unsigned long init_dump_header(struct phyp_dump_header *ph)
 static void print_dump_header(const struct phyp_dump_header *ph)
 {
 #ifdef DEBUG
+	if (ph == NULL)
+		return;
+
 	printk(KERN_INFO "dump header:\n");
 	/* setup some ph->sections required */
 	printk(KERN_INFO "version = %d\n", ph->version);
-- 
1.6.0.4


Yours Tony

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