mm: fix atomic_t overflow in vm
The atomic_t type is 32bit but a 64bit system can have more than 2^32
pages of virtual address space available. Without this we overflow on
ludicrously large mappings
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/swap.c b/mm/swap.c
index 91e1944..45c9f25 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -503,7 +503,7 @@
local = &__get_cpu_var(committed_space);
*local += pages;
if (*local > ACCT_THRESHOLD || *local < -ACCT_THRESHOLD) {
- atomic_add(*local, &vm_committed_space);
+ atomic_long_add(*local, &vm_committed_space);
*local = 0;
}
preempt_enable();
@@ -520,7 +520,7 @@
committed = &per_cpu(committed_space, (long)hcpu);
if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) {
- atomic_add(*committed, &vm_committed_space);
+ atomic_long_add(*committed, &vm_committed_space);
*committed = 0;
drain_cpu_pagevecs((long)hcpu);
}