Merge branch 'akpm' (patches from Andrew)

Merge misc fixes from Andrew Morton:
 "17 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  nilfs2: convert to SPDX license tags
  drivers/dax/device.c: convert variable to vm_fault_t type
  lib/Kconfig.debug: fix three typos in help text
  checkpatch: add __ro_after_init to known $Attribute
  mm: fix BUG_ON() in vmf_insert_pfn_pud() from VM_MIXEDMAP removal
  uapi/linux/keyctl.h: don't use C++ reserved keyword as a struct member name
  memory_hotplug: fix kernel_panic on offline page processing
  checkpatch: add optional static const to blank line declarations test
  ipc/shm: properly return EIDRM in shm_lock()
  mm/hugetlb: filter out hugetlb pages if HUGEPAGE migration is not supported.
  mm/util.c: improve kvfree() kerneldoc
  tools/vm/page-types.c: fix "defined but not used" warning
  tools/vm/slabinfo.c: fix sign-compare warning
  kmemleak: always register debugfs file
  mm: respect arch_dup_mmap() return value
  mm, oom: fix missing tlb_finish_mmu() in __oom_reap_task_mm().
  mm: memcontrol: print proper OOM header when no eligible victim left

7 files changed, 31 insertions, 16 deletions

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index c3bc7e9c9a2a..533f9b00147d 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -821,11 +821,11 @@ vm_fault_t vmf_insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr,
 	 * but we need to be consistent with PTEs and architectures that
 	 * can't support a 'special' bit.
 	 */
-	BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)));
+	BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) &&
+			!pfn_t_devmap(pfn));
 	BUG_ON((vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) ==
 						(VM_PFNMAP|VM_MIXEDMAP));
 	BUG_ON((vma->vm_flags & VM_PFNMAP) && is_cow_mapping(vma->vm_flags));
-	BUG_ON(!pfn_t_devmap(pfn));
 
 	if (addr < vma->vm_start || addr >= vma->vm_end)
 		return VM_FAULT_SIGBUS;
diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index 9a085d525bbc..17dd883198ae 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -2097,6 +2097,11 @@ static int __init kmemleak_late_init(void)
 
 	kmemleak_initialized = 1;
 
+	dentry = debugfs_create_file("kmemleak", 0644, NULL, NULL,
+				     &kmemleak_fops);
+	if (!dentry)
+		pr_warn("Failed to create the debugfs kmemleak file\n");
+
 	if (kmemleak_error) {
 		/*
 		 * Some error occurred and kmemleak was disabled. There is a
@@ -2108,10 +2113,6 @@ static int __init kmemleak_late_init(void)
 		return -ENOMEM;
 	}
 
-	dentry = debugfs_create_file("kmemleak", 0644, NULL, NULL,
-				     &kmemleak_fops);
-	if (!dentry)
-		pr_warn("Failed to create the debugfs kmemleak file\n");
 	mutex_lock(&scan_mutex);
 	start_scan_thread();
 	mutex_unlock(&scan_mutex);
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 4ead5a4817de..e79cb59552d9 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1701,8 +1701,6 @@ static enum oom_status mem_cgroup_oom(struct mem_cgroup *memcg, gfp_t mask, int
 	if (mem_cgroup_out_of_memory(memcg, mask, order))
 		return OOM_SUCCESS;
 
-	WARN(1,"Memory cgroup charge failed because of no reclaimable memory! "
-		"This looks like a misconfiguration or a kernel bug.");
 	return OOM_FAILED;
 }
 
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 9eea6e809a4e..38d94b703e9d 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1333,7 +1333,8 @@ static unsigned long scan_movable_pages(unsigned long start, unsigned long end)
 			if (__PageMovable(page))
 				return pfn;
 			if (PageHuge(page)) {
-				if (page_huge_active(page))
+				if (hugepage_migration_supported(page_hstate(page)) &&
+				    page_huge_active(page))
 					return pfn;
 				else
 					pfn = round_up(pfn + 1,
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index b5b25e4dcbbb..f10aa5360616 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -522,6 +522,7 @@ bool __oom_reap_task_mm(struct mm_struct *mm)
 
 			tlb_gather_mmu(&tlb, mm, start, end);
 			if (mmu_notifier_invalidate_range_start_nonblock(mm, start, end)) {
+				tlb_finish_mmu(&tlb, start, end);
 				ret = false;
 				continue;
 			}
@@ -1103,10 +1104,17 @@ bool out_of_memory(struct oom_control *oc)
 	}
 
 	select_bad_process(oc);
-	/* Found nothing?!?! Either we hang forever, or we panic. */
-	if (!oc->chosen && !is_sysrq_oom(oc) && !is_memcg_oom(oc)) {
+	/* Found nothing?!?! */
+	if (!oc->chosen) {
 		dump_header(oc, NULL);
-		panic("Out of memory and no killable processes...\n");
+		pr_warn("Out of memory and no killable processes...\n");
+		/*
+		 * If we got here due to an actual allocation at the
+		 * system level, we cannot survive this and will enter
+		 * an endless loop in the allocator. Bail out now.
+		 */
+		if (!is_sysrq_oom(oc) && !is_memcg_oom(oc))
+			panic("System is deadlocked on memory\n");
 	}
 	if (oc->chosen && oc->chosen != (void *)-1UL)
 		oom_kill_process(oc, !is_memcg_oom(oc) ? "Out of memory" :
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 05e983f42316..89d2a2ab3fe6 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -7708,6 +7708,10 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
 		 * handle each tail page individually in migration.
 		 */
 		if (PageHuge(page)) {
+
+			if (!hugepage_migration_supported(page_hstate(page)))
+				goto unmovable;
+
 			iter = round_up(iter + 1, 1<<compound_order(page)) - 1;
 			continue;
 		}
diff --git a/mm/util.c b/mm/util.c
index d2890a407332..9e3ebd2ef65f 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -435,11 +435,14 @@ void *kvmalloc_node(size_t size, gfp_t flags, int node)
 EXPORT_SYMBOL(kvmalloc_node);
 
 /**
- * kvfree - free memory allocated with kvmalloc
- * @addr: pointer returned by kvmalloc
+ * kvfree() - Free memory.
+ * @addr: Pointer to allocated memory.
  *
- * If the memory is allocated from vmalloc area it is freed with vfree().
- * Otherwise kfree() is used.
+ * kvfree frees memory allocated by any of vmalloc(), kmalloc() or kvmalloc().
+ * It is slightly more efficient to use kfree() or vfree() if you are certain
+ * that you know which one to use.
+ *
+ * Context: Any context except NMI.
  */
 void kvfree(const void *addr)
 {