vmalloc_32 should use GFP_KERNEL

I've noticed lots of failures of vmalloc_32 on machines where it
shouldn't have failed unless it was doing an atomic operation.

Looking closely, I noticed that:

#if defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA32)
#define GFP_VMALLOC32 GFP_DMA32
#elif defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA)
#define GFP_VMALLOC32 GFP_DMA
#else
#define GFP_VMALLOC32 GFP_KERNEL
#endif

Which seems to be incorrect, it should always -or- in the DMA flags
on top of GFP_KERNEL, thus this patch.

This fixes frequent errors launchin X with the nouveau DRM for example.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Andi Kleen <ak@suse.de>
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/vmalloc.c

@@ -583,9 +583,9 @@ void *vmalloc_exec(unsigned long size)
 }
 
 #if defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA32)
-#define GFP_VMALLOC32 GFP_DMA32
+#define GFP_VMALLOC32 GFP_DMA32 | GFP_KERNEL
 #elif defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA)
-#define GFP_VMALLOC32 GFP_DMA
+#define GFP_VMALLOC32 GFP_DMA | GFP_KERNEL
 #else
 #define GFP_VMALLOC32 GFP_KERNEL
 #endif