[PATCH] scatterlist: don't BUG when we can trivially return a proper error.

[Nick Bowler <nbowler@elliptictech.com>]

There is absolutely no reason to crash the kernel when we have a
perfectly good return value already available to use for conveying
failure status.

Let's return an error code instead of crashing the kernel: that sounds
like a much better plan.

Signed-off-by: Nick Bowler <nbowler@elliptictech.com>
---
 lib/scatterlist.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/lib/scatterlist.c b/lib/scatterlist.c
index 3675452b23ca..11ecaf000696 100644
--- a/lib/scatterlist.c
+++ b/lib/scatterlist.c
@@ -248,7 +248,8 @@ int __sg_alloc_table(struct sg_table *table, unsigned int nents,
 	unsigned int left;
 
 #ifndef ARCH_HAS_SG_CHAIN
-	BUG_ON(nents > max_ents);
+	if (WARN_ON_ONCE(nents > max_ents))
+		return -E2BIG;
 #endif
 
 	memset(table, 0, sizeof(*table));
-- 
1.7.8.6