[PATCH] uml: switch_mm fix

Not quite, something along the lines of the patch below works correctly (and
makes aio performance not suffer from multiple second delays), as skas0 mode
correctly switches mm contexts, unlike TT (which should probably get nuked
from the kernel now that skas0 seems to be working).
Signed-off-by: NBenjamin LaHaise <bcrl@linux.intel.com>
Signed-off-by: NJeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

include/asm-um/mmu_context.h

@@ -29,7 +29,8 @@ static inline void activate_mm(struct mm_struct *old, struct mm_struct *new)
 	 * possible.
 	 */
 	if (old != new && (current->flags & PF_BORROWED_MM))
-		force_flush_all();
+		CHOOSE_MODE(force_flush_all(),
+			    switch_mm_skas(&new->context.skas.id));
 }
 
 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,