Merge branch 'akpm' (patches from Andrew)

Merge misc fixes from Andrew Morton:
 "10 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm: move pcp and lru-pcp draining into single wq
  mailmap: update Yakir Yang email address
  mm, swap_cgroup: reschedule when neeed in swap_cgroup_swapoff()
  dax: fix radix tree insertion race
  mm, thp: fix setting of defer+madvise thp defrag mode
  ptrace: fix PTRACE_LISTEN race corrupting task->state
  vmlinux.lds: add missing VMLINUX_SYMBOL macros
  mm/page_alloc.c: fix print order in show_free_areas()
  userfaultfd: report actual registered features in fdinfo
  mm: fix page_vma_mapped_walk() for ksm pages

2 files changed, 23 insertions, 14 deletions

diff --git a/fs/dax.c b/fs/dax.c
index de622d4282a6..85abd741253d 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -373,6 +373,22 @@ restart:
 		}
 		spin_lock_irq(&mapping->tree_lock);
 
+		if (!entry) {
+			/*
+			 * We needed to drop the page_tree lock while calling
+			 * radix_tree_preload() and we didn't have an entry to
+			 * lock.  See if another thread inserted an entry at
+			 * our index during this time.
+			 */
+			entry = __radix_tree_lookup(&mapping->page_tree, index,
+					NULL, &slot);
+			if (entry) {
+				radix_tree_preload_end();
+				spin_unlock_irq(&mapping->tree_lock);
+				goto restart;
+			}
+		}
+
 		if (pmd_downgrade) {
 			radix_tree_delete(&mapping->page_tree, index);
 			mapping->nrexceptional--;
@@ -388,19 +404,12 @@ restart:
 		if (err) {
 			spin_unlock_irq(&mapping->tree_lock);
 			/*
-			 * Someone already created the entry?  This is a
-			 * normal failure when inserting PMDs in a range
-			 * that already contains PTEs.  In that case we want
-			 * to return -EEXIST immediately.
-			 */
-			if (err == -EEXIST && !(size_flag & RADIX_DAX_PMD))
-				goto restart;
-			/*
-			 * Our insertion of a DAX PMD entry failed, most
-			 * likely because it collided with a PTE sized entry
-			 * at a different index in the PMD range.  We haven't
-			 * inserted anything into the radix tree and have no
-			 * waiters to wake.
+			 * Our insertion of a DAX entry failed, most likely
+			 * because we were inserting a PMD entry and it
+			 * collided with a PTE sized entry at a different
+			 * index in the PMD range.  We haven't inserted
+			 * anything into the radix tree and have no waiters to
+			 * wake.
 			 */
 			return ERR_PTR(err);
 		}
diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c
index 1d227b0fcf49..f7555fc25877 100644
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -1756,7 +1756,7 @@ static void userfaultfd_show_fdinfo(struct seq_file *m, struct file *f)
 	 *	protocols: aa:... bb:...
 	 */
 	seq_printf(m, "pending:\t%lu\ntotal:\t%lu\nAPI:\t%Lx:%x:%Lx\n",
-		   pending, total, UFFD_API, UFFD_API_FEATURES,
+		   pending, total, UFFD_API, ctx->features,
 		   UFFD_API_IOCTLS|UFFD_API_RANGE_IOCTLS);
 }
 #endif