Merge branch 'akpm' (second patch-bomb from Andrew)

Merge second patchbomb from Andrew Morton:
 - the rest of MM
 - misc fs fixes
 - add execveat() syscall
 - new ratelimit feature for fault-injection
 - decompressor updates
 - ipc/ updates
 - fallocate feature creep
 - fsnotify cleanups
 - a few other misc things

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (99 commits)
  cgroups: Documentation: fix trivial typos and wrong paragraph numberings
  parisc: percpu: update comments referring to __get_cpu_var
  percpu: update local_ops.txt to reflect this_cpu operations
  percpu: remove __get_cpu_var and __raw_get_cpu_var macros
  fsnotify: remove destroy_list from fsnotify_mark
  fsnotify: unify inode and mount marks handling
  fallocate: create FAN_MODIFY and IN_MODIFY events
  mm/cma: make kmemleak ignore CMA regions
  slub: fix cpuset check in get_any_partial
  slab: fix cpuset check in fallback_alloc
  shmdt: use i_size_read() instead of ->i_size
  ipc/shm.c: fix overly aggressive shmdt() when calls span multiple segments
  ipc/msg: increase MSGMNI, remove scaling
  ipc/sem.c: increase SEMMSL, SEMMNI, SEMOPM
  ipc/sem.c: change memory barrier in sem_lock() to smp_rmb()
  lib/decompress.c: consistency of compress formats for kernel image
  decompress_bunzip2: off by one in get_next_block()
  usr/Kconfig: make initrd compression algorithm selection not expert
  fault-inject: add ratelimit option
  ratelimit: add initialization macro
  ...

1 files changed, 10 insertions, 3 deletions

diff --git a/ipc/sem.c b/ipc/sem.c
index 53c3310f41c6..6115146563f9 100644
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -326,10 +326,17 @@ static inline int sem_lock(struct sem_array *sma, struct sembuf *sops,
 
                 /* Then check that the global lock is free */
                 if (!spin_is_locked(&sma->sem_perm.lock)) {
-                        /* spin_is_locked() is not a memory barrier */
-                        smp_mb();
+                        /*
+                         * The ipc object lock check must be visible on all
+                         * cores before rechecking the complex count.  Otherwise
+                         * we can race with  another thread that does:
+                         *      complex_count++;
+                         *      spin_unlock(sem_perm.lock);
+                         */
+                        smp_rmb();
 
-                        /* Now repeat the test of complex_count:
+                        /*
+                         * Now repeat the test of complex_count:
                          * It can't change anymore until we drop sem->lock.
                          * Thus: if is now 0, then it will stay 0.
                          */