[PATCH 1/2] powerpc/prom: Remove VLA in prom_check_platform_support()

[Suraj Jitindar Singh <sjitindarsingh@gmail.com>]

In prom_check_platform_support() we retrieve and parse the
"ibm,arch-vec-5-platform-support" property of the chosen node.
Currently we use a variable length array however to avoid this use an
array of constant length 8.

This property is used to indicate the supported options of vector 5
bytes 23-26 of the ibm,architecture.vec node. Each of these options
is a pair of bytes, thus for 4 options we have a max length of 8 bytes.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
---
 arch/powerpc/kernel/prom_init.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c
index 9b38a2e5dd35..ce5fc03dc69f 100644
--- a/arch/powerpc/kernel/prom_init.c
+++ b/arch/powerpc/kernel/prom_init.c
@@ -1131,12 +1131,15 @@ static void __init prom_check_platform_support(void)
 				       "ibm,arch-vec-5-platform-support");
 	if (prop_len > 1) {
 		int i;
-		u8 vec[prop_len];
+		u8 vec[8];
 		prom_debug("Found ibm,arch-vec-5-platform-support, len: %d\n",
 			   prop_len);
+		if (prop_len > sizeof(vec))
+			prom_printf("WARNING: ibm,arch-vec-5-platform-support longer "\
+				    " than expected (len: %d)\n", prop_len);
 		prom_getprop(prom.chosen, "ibm,arch-vec-5-platform-support",
 			     &vec, sizeof(vec));
-		for (i = 0; i < prop_len; i += 2) {
+		for (i = 0; i < sizeof(vec); i += 2) {
 			prom_debug("%d: index = 0x%x val = 0x%x\n", i / 2
 								  , vec[i]
 								  , vec[i + 1]);
-- 
2.13.6