x86: Use helpers for rlimits

Make sure compiler won't do weird things with limits.  Fetching them
twice may return 2 different values after writable limits are
implemented.

We can either use rlimit helpers added in
3e10e716abf3c71bdb5d86b8f507f9e72236c9cd or ACCESS_ONCE if not
applicable; this patch uses the helpers.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
LKML-Reference: <1264609942-24621-1-git-send-email-jslaby@suse.cz>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c
index c8191defc38a..1dab5194fd9d 100644
--- a/arch/x86/mm/mmap.c
+++ b/arch/x86/mm/mmap.c
@@ -71,7 +71,7 @@ static int mmap_is_legacy(void)
         if (current->personality & ADDR_COMPAT_LAYOUT)
                 return 1;
 
-        if (current->signal->rlim[RLIMIT_STACK].rlim_cur == RLIM_INFINITY)
+        if (rlimit(RLIMIT_STACK) == RLIM_INFINITY)
                 return 1;
 
         return sysctl_legacy_va_layout;
@@ -96,7 +96,7 @@ static unsigned long mmap_rnd(void)
 
 static unsigned long mmap_base(void)
 {
-        unsigned long gap = current->signal->rlim[RLIMIT_STACK].rlim_cur;
+        unsigned long gap = rlimit(RLIMIT_STACK);
 
         if (gap < MIN_GAP)
                 gap = MIN_GAP;