SPARC: use helpers for rlimits

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

I.e. either use rlimit helpers added in
3e10e716abf3c71bdb5d86b8f507f9e72236c9cd
or ACCESS_ONCE if not applicable.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/arch/sparc/kernel/sys_sparc_64.c b/arch/sparc/kernel/sys_sparc_64.c
index cfa0e19abe3bd62b2e0f64f2b5b5d15499b0b9c9..d77f54316948e83cdc035c9e04d76cbd8d4702a1 100644 (file)
--- a/arch/sparc/kernel/sys_sparc_64.c
+++ b/arch/sparc/kernel/sys_sparc_64.c
@@ -365,6 +365,7 @@ EXPORT_SYMBOL(get_fb_unmapped_area);
 void arch_pick_mmap_layout(struct mm_struct *mm)
 {
        unsigned long random_factor = 0UL;
+       unsigned long gap;
 
        if (current->flags & PF_RANDOMIZE) {
                random_factor = get_random_int();
@@ -379,9 +380,10 @@ void arch_pick_mmap_layout(struct mm_struct *mm)
         * Fall back to the standard layout if the personality
         * bit is set, or if the expected stack growth is unlimited:
         */
+       gap = rlimit(RLIMIT_STACK);
        if (!test_thread_flag(TIF_32BIT) ||
            (current->personality & ADDR_COMPAT_LAYOUT) ||
-           current->signal->rlim[RLIMIT_STACK].rlim_cur == RLIM_INFINITY ||
+           gap == RLIM_INFINITY ||
            sysctl_legacy_va_layout) {
                mm->mmap_base = TASK_UNMAPPED_BASE + random_factor;
                mm->get_unmapped_area = arch_get_unmapped_area;
@@ -389,9 +391,7 @@ void arch_pick_mmap_layout(struct mm_struct *mm)
        } else {
                /* We know it's 32-bit */
                unsigned long task_size = STACK_TOP32;
-               unsigned long gap;
 
-               gap = current->signal->rlim[RLIMIT_STACK].rlim_cur;
                if (gap < 128 * 1024 * 1024)
                        gap = 128 * 1024 * 1024;
                if (gap > (task_size / 6 * 5))