[PATCH v2 1/1] mm: move bad zone checking in gfp_zone()

[Wang Yibo]

When flags in gfp_zone() has an error combination,
VM_BUG_ON() should first know it before use it.

Signed-off-by: Wang Yibo <wangyibo@xxxxxxxxxxxxx>
---
 include/linux/gfp.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index f53f76e0b17e..ca61b2440ab3 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -133,10 +133,11 @@ static inline enum zone_type gfp_zone(gfp_t flags)
 {
 	enum zone_type z;
 	int bit = (__force int) (flags & GFP_ZONEMASK);
+	VM_BUG_ON((GFP_ZONE_BAD >> bit) & 1);
 
 	z = (GFP_ZONE_TABLE >> (bit * GFP_ZONES_SHIFT)) &
 					 ((1 << GFP_ZONES_SHIFT) - 1);
-	VM_BUG_ON((GFP_ZONE_BAD >> bit) & 1);
+
 	return z;
 }
 
-- 
2.20.1