Merge branch 'akpm' (patches from Andrew)

Merge updates from Andrew Morton:

 - a few misc bits

 - ocfs2 updates

 - almost all of MM

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (131 commits)
  memory hotplug: fix comments when adding section
  mm: make alloc_node_mem_map a void call if we don't have CONFIG_FLAT_NODE_MEM_MAP
  mm: simplify nodemask printing
  mm,oom_reaper: remove pointless kthread_run() error check
  mm/page_ext.c: check if page_ext is not prepared
  writeback: remove unused function parameter
  mm: do not rely on preempt_count in print_vma_addr
  mm, sparse: do not swamp log with huge vmemmap allocation failures
  mm/hmm: remove redundant variable align_end
  mm/list_lru.c: mark expected switch fall-through
  mm/shmem.c: mark expected switch fall-through
  mm/page_alloc.c: broken deferred calculation
  mm: don't warn about allocations which stall for too long
  fs: fuse: account fuse_inode slab memory as reclaimable
  mm, page_alloc: fix potential false positive in __zone_watermark_ok
  mm: mlock: remove lru_add_drain_all()
  mm, sysctl: make NUMA stats configurable
  shmem: convert shmem_init_inodecache() to void
  Unify migrate_pages and move_pages access checks
  mm, pagevec: rename pagevec drained field
  ...

1 files changed, 7 insertions, 9 deletions

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index a2af6d58a68f..4ce44d3ff03d 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -85,6 +85,7 @@
 #include <linux/interrupt.h>
 #include <linux/init.h>
 #include <linux/compat.h>
+#include <linux/ptrace.h>
 #include <linux/swap.h>
 #include <linux/seq_file.h>
 #include <linux/proc_fs.h>
@@ -1365,7 +1366,6 @@ SYSCALL_DEFINE4(migrate_pages, pid_t, pid, unsigned long, maxnode,
 		const unsigned long __user *, old_nodes,
 		const unsigned long __user *, new_nodes)
 {
-	const struct cred *cred = current_cred(), *tcred;
 	struct mm_struct *mm = NULL;
 	struct task_struct *task;
 	nodemask_t task_nodes;
@@ -1401,15 +1401,10 @@ SYSCALL_DEFINE4(migrate_pages, pid_t, pid, unsigned long, maxnode,
 	err = -EINVAL;
 
 	/*
-	 * Check if this process has the right to modify the specified
-	 * process. The right exists if the process has administrative
-	 * capabilities, superuser privileges or the same
-	 * userid as the target process.
+	 * Check if this process has the right to modify the specified process.
+	 * Use the regular "ptrace_may_access()" checks.
 	 */
-	tcred = __task_cred(task);
-	if (!uid_eq(cred->euid, tcred->suid) && !uid_eq(cred->euid, tcred->uid) &&
-	    !uid_eq(cred->uid,  tcred->suid) && !uid_eq(cred->uid,  tcred->uid) &&
-	    !capable(CAP_SYS_NICE)) {
+	if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) {
 		rcu_read_unlock();
 		err = -EPERM;
 		goto out_put;
@@ -1920,6 +1915,9 @@ static struct page *alloc_page_interleave(gfp_t gfp, unsigned order,
 	struct page *page;
 
 	page = __alloc_pages(gfp, order, nid);
+	/* skip NUMA_INTERLEAVE_HIT counter update if numa stats is disabled */
+	if (!static_branch_likely(&vm_numa_stat_key))
+		return page;
 	if (page && page_to_nid(page) == nid) {
 		preempt_disable();
 		__inc_numa_state(page_zone(page), NUMA_INTERLEAVE_HIT);