Merge branch 'akpm' (patches from Andrew)

Merge misc fixes from Andrew Morton:
 "13 patches.

  Subsystems affected by this patch series: mm (memory-failure, memcg,
  userfaultfd, hugetlbfs, mremap, oom-kill, kasan, hmm), and kcov"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm/mmu_notifier.c: fix race in mmu_interval_notifier_remove()
  kcov: don't generate a warning on vm_insert_page()'s failure
  MAINTAINERS: add Vincenzo Frascino to KASAN reviewers
  oom_kill.c: futex: delay the OOM reaper to allow time for proper futex cleanup
  selftest/vm: add skip support to mremap_test
  selftest/vm: support xfail in mremap_test
  selftest/vm: verify remap destination address in mremap_test
  selftest/vm: verify mmap addr in mremap_test
  mm, hugetlb: allow for "high" userspace addresses
  userfaultfd: mark uffd_wp regardless of VM_WRITE flag
  memcg: sync flush only if periodic flush is delayed
  mm/memory-failure.c: skip huge_zero_page in memory_failure()
  mm/hwpoison: fix race between hugetlb free/demotion and memory_failure_hugetlb()

5 files changed, 28 insertions, 0 deletions

diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 53c1b6082a4c..ac2a1d758a80 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -169,6 +169,7 @@ long hugetlb_unreserve_pages(struct inode *inode, long start, long end,
 						long freed);
 bool isolate_huge_page(struct page *page, struct list_head *list);
 int get_hwpoison_huge_page(struct page *page, bool *hugetlb);
+int get_huge_page_for_hwpoison(unsigned long pfn, int flags);
 void putback_active_hugepage(struct page *page);
 void move_hugetlb_state(struct page *oldpage, struct page *newpage, int reason);
 void free_huge_page(struct page *page);
@@ -378,6 +379,11 @@ static inline int get_hwpoison_huge_page(struct page *page, bool *hugetlb)
 	return 0;
 }
 
+static inline int get_huge_page_for_hwpoison(unsigned long pfn, int flags)
+{
+	return 0;
+}
+
 static inline void putback_active_hugepage(struct page *page)
 {
 }
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index a68dce3873fc..89b14729d59f 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -1012,6 +1012,7 @@ static inline unsigned long lruvec_page_state_local(struct lruvec *lruvec,
 }
 
 void mem_cgroup_flush_stats(void);
+void mem_cgroup_flush_stats_delayed(void);
 
 void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx,
 			      int val);
@@ -1455,6 +1456,10 @@ static inline void mem_cgroup_flush_stats(void)
 {
 }
 
+static inline void mem_cgroup_flush_stats_delayed(void)
+{
+}
+
 static inline void __mod_memcg_lruvec_state(struct lruvec *lruvec,
 					    enum node_stat_item idx, int val)
 {
diff --git a/include/linux/mm.h b/include/linux/mm.h
index e34edb775334..9f44254af8ce 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -3197,6 +3197,14 @@ extern int sysctl_memory_failure_recovery;
 extern void shake_page(struct page *p);
 extern atomic_long_t num_poisoned_pages __read_mostly;
 extern int soft_offline_page(unsigned long pfn, int flags);
+#ifdef CONFIG_MEMORY_FAILURE
+extern int __get_huge_page_for_hwpoison(unsigned long pfn, int flags);
+#else
+static inline int __get_huge_page_for_hwpoison(unsigned long pfn, int flags)
+{
+	return 0;
+}
+#endif
 
 #ifndef arch_memory_failure
 static inline int arch_memory_failure(unsigned long pfn, int flags)
diff --git a/include/linux/sched.h b/include/linux/sched.h
index d5e3c00b74e1..a8911b1f35aa 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1443,6 +1443,7 @@ struct task_struct {
 	int				pagefault_disabled;
 #ifdef CONFIG_MMU
 	struct task_struct		*oom_reaper_list;
+	struct timer_list		oom_reaper_timer;
 #endif
 #ifdef CONFIG_VMAP_STACK
 	struct vm_struct		*stack_vm_area;
diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h
index a80356e9dc69..1ad1f4bfa025 100644
--- a/include/linux/sched/mm.h
+++ b/include/linux/sched/mm.h
@@ -136,6 +136,14 @@ static inline void mm_update_next_owner(struct mm_struct *mm)
 #endif /* CONFIG_MEMCG */
 
 #ifdef CONFIG_MMU
+#ifndef arch_get_mmap_end
+#define arch_get_mmap_end(addr)	(TASK_SIZE)
+#endif
+
+#ifndef arch_get_mmap_base
+#define arch_get_mmap_base(addr, base) (base)
+#endif
+
 extern void arch_pick_mmap_layout(struct mm_struct *mm,
 				  struct rlimit *rlim_stack);
 extern unsigned long