sparc64: do not clobber personality flags in sys_sparc64_personality()
authorJiri Kosina <jkosina@suse.cz>
Wed, 1 Aug 2012 19:10:51 +0000 (21:10 +0200)
committerDavid S. Miller <davem@davemloft.net>
Thu, 2 Aug 2012 07:26:50 +0000 (00:26 -0700)
commita27032eee8cb6e16516f13c8a9752e9d5d4cc430
treec8db15dbfa5e724fb70fb4d812288281597bcaf3
parent1a9b4993b70fb1884716902774dc9025b457760d
sparc64: do not clobber personality flags in sys_sparc64_personality()

There are multiple errors in how sys_sparc64_personality() handles
personality flags stored in top three bytes.

- directly comparing current->personality against PER_LINUX32 doesn't work
  in cases when any of the personality flags stored in the top three bytes
  are used.
- directly forcefully setting personality to PER_LINUX32 or PER_LINUX
  discards any flags stored in the top three bytes

Fix the first one by properly using personality() macro to compare only
PER_MASK bytes.
Fix the second one by setting only the bits that should be set, instead of
overwriting the whole value.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
arch/sparc/kernel/sys_sparc_64.c