x86/mpx: Clean up the code by not passing a task pointer around when unnecessary

The MPX code can only work on the current task.  You can not,
for instance, enable MPX management in another process or
thread. You can also not handle a fault for another process or
thread.

Despite this, we pass a task_struct around prolifically.  This
patch removes all of the task struct passing for code paths
where the code can not deal with another task (which turns out
to be all of them).

This has no functional changes.  It's just a cleanup.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Hansen <dave@sr71.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: bp@alien8.de
Link: http://lkml.kernel.org/r/20150607183702.6A81DA2C@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 4 insertions, 4 deletions

diff --git a/kernel/sys.c b/kernel/sys.c
index a4e372b798a5..8571296b7ddb 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -92,10 +92,10 @@
 # define SET_TSC_CTL(a)         (-EINVAL)
 #endif
 #ifndef MPX_ENABLE_MANAGEMENT
-# define MPX_ENABLE_MANAGEMENT(a)       (-EINVAL)
+# define MPX_ENABLE_MANAGEMENT()        (-EINVAL)
 #endif
 #ifndef MPX_DISABLE_MANAGEMENT
-# define MPX_DISABLE_MANAGEMENT(a)      (-EINVAL)
+# define MPX_DISABLE_MANAGEMENT()       (-EINVAL)
 #endif
 #ifndef GET_FP_MODE
 # define GET_FP_MODE(a)         (-EINVAL)
@@ -2230,12 +2230,12 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
         case PR_MPX_ENABLE_MANAGEMENT:
                 if (arg2 || arg3 || arg4 || arg5)
                         return -EINVAL;
-                error = MPX_ENABLE_MANAGEMENT(me);
+                error = MPX_ENABLE_MANAGEMENT();
                 break;
         case PR_MPX_DISABLE_MANAGEMENT:
                 if (arg2 || arg3 || arg4 || arg5)
                         return -EINVAL;
-                error = MPX_DISABLE_MANAGEMENT(me);
+                error = MPX_DISABLE_MANAGEMENT();
                 break;
         case PR_SET_FP_MODE:
                 error = SET_FP_MODE(me, arg2);