x86/AMD/NB: Fix amd_set_subcaches() parameter type

This is under CAP_SYS_ADMIN, but Smatch complains that mask comes
from the user and the test for "mask > 0xf" can underflow.

The fix is simple: amd_set_subcaches() should hand down not an 'int'
but an 'unsigned long' like it was originally indended to do.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel J Blueman <daniel@numascale-asia.com>
Link: http://lkml.kernel.org/r/20140121072209.GA22095@elgon.mountain
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/include/asm/amd_nb.h

@@ -19,7 +19,7 @@ extern int amd_cache_northbridges(void);
 extern void amd_flush_garts(void);
 extern int amd_numa_init(void);
 extern int amd_get_subcaches(int);
-extern int amd_set_subcaches(int, int);
+extern int amd_set_subcaches(int, unsigned long);
 
 struct amd_l3_cache {
 	unsigned indices;

arch/x86/kernel/amd_nb.c

@@ -179,7 +179,7 @@ int amd_get_subcaches(int cpu)
 	return (mask >> (4 * cuid)) & 0xf;
 }
 
-int amd_set_subcaches(int cpu, int mask)
+int amd_set_subcaches(int cpu, unsigned long mask)
 {
 	static unsigned int reset, ban;
 	struct amd_northbridge *nb = node_to_amd_nb(amd_get_nb_id(cpu));