powerpc+sparc64/mm: Remove hack in mmap randomize layout

Since commit 8a0a9bd4db63bc45e301, this comment in mmap_rnd() does not
hold true as the value returned by get_random_int() will in fact be

different every single call. Remove the comment and simplify the code
back to its original desired form.

This reverts commit a5adc91a4b44b5d1 which is no longer necessary and
also fixes the sparc code that copied this same adjustment.

Signed-off-by: Dan McGee <dpmcgee@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 3 insertions, 3 deletions

diff --git a/arch/sparc/kernel/sys_sparc_64.c b/arch/sparc/kernel/sys_sparc_64.c
index 441521ad8a3f..232df9949530 100644
--- a/arch/sparc/kernel/sys_sparc_64.c
+++ b/arch/sparc/kernel/sys_sparc_64.c
@@ -368,11 +368,11 @@ static unsigned long mmap_rnd(void)
         if (current->flags & PF_RANDOMIZE) {
                 unsigned long val = get_random_int();
                 if (test_thread_flag(TIF_32BIT))
-                        rnd = (val % (1UL << (22UL-PAGE_SHIFT)));
+                        rnd = (val % (1UL << (23UL-PAGE_SHIFT)));
                 else
-                        rnd = (val % (1UL << (29UL-PAGE_SHIFT)));
+                        rnd = (val % (1UL << (30UL-PAGE_SHIFT)));
         }
-        return (rnd << PAGE_SHIFT) * 2;
+        return rnd << PAGE_SHIFT;
 }
 
 void arch_pick_mmap_layout(struct mm_struct *mm)