Merge branch 'akpm' (patches from Andrew)

Merge more updates from Andrew Morton:
 "87 patches.

  Subsystems affected by this patch series: mm (pagecache and hugetlb),
  procfs, misc, MAINTAINERS, lib, checkpatch, binfmt, kallsyms, ramfs,
  init, codafs, nilfs2, hfs, crash_dump, signals, seq_file, fork,
  sysvfs, kcov, gdb, resource, selftests, and ipc"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (87 commits)
  ipc/ipc_sysctl.c: remove fallback for !CONFIG_PROC_SYSCTL
  ipc: check checkpoint_restore_ns_capable() to modify C/R proc files
  selftests/kselftest/runner/run_one(): allow running non-executable files
  virtio-mem: disallow mapping virtio-mem memory via /dev/mem
  kernel/resource: disallow access to exclusive system RAM regions
  kernel/resource: clean up and optimize iomem_is_exclusive()
  scripts/gdb: handle split debug for vmlinux
  kcov: replace local_irq_save() with a local_lock_t
  kcov: avoid enable+disable interrupts if !in_task()
  kcov: allocate per-CPU memory on the relevant node
  Documentation/kcov: define `ip' in the example
  Documentation/kcov: include types.h in the example
  sysv: use BUILD_BUG_ON instead of runtime check
  kernel/fork.c: unshare(): use swap() to make code cleaner
  seq_file: fix passing wrong private data
  seq_file: move seq_escape() to a header
  signal: remove duplicate include in signal.h
  crash_dump: remove duplicate include in crash_dump.h
  crash_dump: fix boolreturn.cocci warning
  hfs/hfsplus: use WARN_ON for sanity check
  ...

9 files changed, 60 insertions, 33 deletions

diff --git a/mm/Kconfig b/mm/Kconfig
index ae1f151c2924..068ce591a13a 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -109,6 +109,13 @@ config NUMA_KEEP_MEMINFO
 config MEMORY_ISOLATION
 	bool
 
+# IORESOURCE_SYSTEM_RAM regions in the kernel resource tree that are marked
+# IORESOURCE_EXCLUSIVE cannot be mapped to user space, for example, via
+# /dev/mem.
+config EXCLUSIVE_SYSTEM_RAM
+	def_bool y
+	depends on !DEVMEM || STRICT_DEVMEM
+
 #
 # Only be set on architectures that have completely implemented memory hotplug
 # feature. If you are not sure, don't touch it.
diff --git a/mm/filemap.c b/mm/filemap.c
index 615512caa0b5..daa0e23a6ee6 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -261,9 +261,13 @@ void delete_from_page_cache(struct page *page)
 	struct address_space *mapping = page_mapping(page);
 
 	BUG_ON(!PageLocked(page));
+	spin_lock(&mapping->host->i_lock);
 	xa_lock_irq(&mapping->i_pages);
 	__delete_from_page_cache(page, NULL);
 	xa_unlock_irq(&mapping->i_pages);
+	if (mapping_shrinkable(mapping))
+		inode_add_lru(mapping->host);
+	spin_unlock(&mapping->host->i_lock);
 
 	page_cache_free_page(mapping, page);
 }
@@ -339,6 +343,7 @@ void delete_from_page_cache_batch(struct address_space *mapping,
 	if (!pagevec_count(pvec))
 		return;
 
+	spin_lock(&mapping->host->i_lock);
 	xa_lock_irq(&mapping->i_pages);
 	for (i = 0; i < pagevec_count(pvec); i++) {
 		trace_mm_filemap_delete_from_page_cache(pvec->pages[i]);
@@ -347,6 +352,9 @@ void delete_from_page_cache_batch(struct address_space *mapping,
 	}
 	page_cache_delete_batch(mapping, pvec);
 	xa_unlock_irq(&mapping->i_pages);
+	if (mapping_shrinkable(mapping))
+		inode_add_lru(mapping->host);
+	spin_unlock(&mapping->host->i_lock);
 
 	for (i = 0; i < pagevec_count(pvec); i++)
 		page_cache_free_page(mapping, pvec->pages[i]);
diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index 9da071ad930c..0bc10f452f7e 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -132,20 +132,11 @@ static void end_report(unsigned long *flags, unsigned long addr)
 	kasan_enable_current();
 }
 
-static void print_stack(depot_stack_handle_t stack)
-{
-	unsigned long *entries;
-	unsigned int nr_entries;
-
-	nr_entries = stack_depot_fetch(stack, &entries);
-	stack_trace_print(entries, nr_entries, 0);
-}
-
 static void print_track(struct kasan_track *track, const char *prefix)
 {
 	pr_err("%s by task %u:\n", prefix, track->pid);
 	if (track->stack) {
-		print_stack(track->stack);
+		stack_depot_print(track->stack);
 	} else {
 		pr_err("(stack is not available)\n");
 	}
@@ -214,12 +205,12 @@ static void describe_object_stacks(struct kmem_cache *cache, void *object,
 		return;
 	if (alloc_meta->aux_stack[0]) {
 		pr_err("Last potentially related work creation:\n");
-		print_stack(alloc_meta->aux_stack[0]);
+		stack_depot_print(alloc_meta->aux_stack[0]);
 		pr_err("\n");
 	}
 	if (alloc_meta->aux_stack[1]) {
 		pr_err("Second to last potentially related work creation:\n");
-		print_stack(alloc_meta->aux_stack[1]);
+		stack_depot_print(alloc_meta->aux_stack[1]);
 		pr_err("\n");
 	}
 #endif
@@ -235,7 +226,7 @@ static void describe_object(struct kmem_cache *cache, void *object,
 
 static inline bool kernel_or_module_addr(const void *addr)
 {
-	if (addr >= (void *)_stext && addr < (void *)_end)
+	if (is_kernel((unsigned long)addr))
 		return true;
 	if (is_module_address((unsigned long)addr))
 		return true;
diff --git a/mm/memfd.c b/mm/memfd.c
index 081dd33e6a61..9f80f162791a 100644
--- a/mm/memfd.c
+++ b/mm/memfd.c
@@ -297,9 +297,7 @@ SYSCALL_DEFINE2(memfd_create,
 	}
 
 	if (flags & MFD_HUGETLB) {
-		struct ucounts *ucounts = NULL;
-
-		file = hugetlb_file_setup(name, 0, VM_NORESERVE, &ucounts,
+		file = hugetlb_file_setup(name, 0, VM_NORESERVE,
 					HUGETLB_ANONHUGE_INODE,
 					(flags >> MFD_HUGE_SHIFT) &
 					MFD_HUGE_MASK);
diff --git a/mm/mmap.c b/mm/mmap.c
index b22a07f5e761..bfb0ea164a90 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1599,7 +1599,6 @@ unsigned long ksys_mmap_pgoff(unsigned long addr, unsigned long len,
 			goto out_fput;
 		}
 	} else if (flags & MAP_HUGETLB) {
-		struct ucounts *ucounts = NULL;
 		struct hstate *hs;
 
 		hs = hstate_sizelog((flags >> MAP_HUGE_SHIFT) & MAP_HUGE_MASK);
@@ -1615,7 +1614,7 @@ unsigned long ksys_mmap_pgoff(unsigned long addr, unsigned long len,
 		 */
 		file = hugetlb_file_setup(HUGETLB_ANON_FILE, len,
 				VM_NORESERVE,
-				&ucounts, HUGETLB_ANONHUGE_INODE,
+				HUGETLB_ANONHUGE_INODE,
 				(flags >> MAP_HUGE_SHIFT) & MAP_HUGE_MASK);
 		if (IS_ERR(file))
 			return PTR_ERR(file);
diff --git a/mm/page_owner.c b/mm/page_owner.c
index 07b61cdf3d0c..79936db59859 100644
--- a/mm/page_owner.c
+++ b/mm/page_owner.c
@@ -329,8 +329,6 @@ print_page_owner(char __user *buf, size_t count, unsigned long pfn,
 		depot_stack_handle_t handle)
 {
 	int ret, pageblock_mt, page_mt;
-	unsigned long *entries;
-	unsigned int nr_entries;
 	char *kbuf;
 
 	count = min_t(size_t, count, PAGE_SIZE);
@@ -361,8 +359,7 @@ print_page_owner(char __user *buf, size_t count, unsigned long pfn,
 	if (ret >= count)
 		goto err;
 
-	nr_entries = stack_depot_fetch(handle, &entries);
-	ret += stack_trace_snprint(kbuf + ret, count - ret, entries, nr_entries, 0);
+	ret += stack_depot_snprint(handle, kbuf + ret, count - ret, 0);
 	if (ret >= count)
 		goto err;
 
@@ -394,8 +391,6 @@ void __dump_page_owner(const struct page *page)
 	struct page_ext *page_ext = lookup_page_ext(page);
 	struct page_owner *page_owner;
 	depot_stack_handle_t handle;
-	unsigned long *entries;
-	unsigned int nr_entries;
 	gfp_t gfp_mask;
 	int mt;
 
@@ -423,20 +418,17 @@ void __dump_page_owner(const struct page *page)
 		 page_owner->pid, page_owner->ts_nsec, page_owner->free_ts_nsec);
 
 	handle = READ_ONCE(page_owner->handle);
-	if (!handle) {
+	if (!handle)
 		pr_alert("page_owner allocation stack trace missing\n");
-	} else {
-		nr_entries = stack_depot_fetch(handle, &entries);
-		stack_trace_print(entries, nr_entries, 0);
-	}
+	else
+		stack_depot_print(handle);
 
 	handle = READ_ONCE(page_owner->free_handle);
 	if (!handle) {
 		pr_alert("page_owner free stack trace missing\n");
 	} else {
-		nr_entries = stack_depot_fetch(handle, &entries);
 		pr_alert("page last free stack trace:\n");
-		stack_trace_print(entries, nr_entries, 0);
+		stack_depot_print(handle);
 	}
 
 	if (page_owner->last_migrate_reason != -1)
diff --git a/mm/truncate.c b/mm/truncate.c
index 714eaf19821d..cc83a3f7c1ad 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -45,9 +45,13 @@ static inline void __clear_shadow_entry(struct address_space *mapping,
 static void clear_shadow_entry(struct address_space *mapping, pgoff_t index,
 			       void *entry)
 {
+	spin_lock(&mapping->host->i_lock);
 	xa_lock_irq(&mapping->i_pages);
 	__clear_shadow_entry(mapping, index, entry);
 	xa_unlock_irq(&mapping->i_pages);
+	if (mapping_shrinkable(mapping))
+		inode_add_lru(mapping->host);
+	spin_unlock(&mapping->host->i_lock);
 }
 
 /*
@@ -73,8 +77,10 @@ static void truncate_exceptional_pvec_entries(struct address_space *mapping,
 		return;
 
 	dax = dax_mapping(mapping);
-	if (!dax)
+	if (!dax) {
+		spin_lock(&mapping->host->i_lock);
 		xa_lock_irq(&mapping->i_pages);
+	}
 
 	for (i = j; i < pagevec_count(pvec); i++) {
 		struct page *page = pvec->pages[i];
@@ -93,8 +99,12 @@ static void truncate_exceptional_pvec_entries(struct address_space *mapping,
 		__clear_shadow_entry(mapping, index, page);
 	}
 
-	if (!dax)
+	if (!dax) {
 		xa_unlock_irq(&mapping->i_pages);
+		if (mapping_shrinkable(mapping))
+			inode_add_lru(mapping->host);
+		spin_unlock(&mapping->host->i_lock);
+	}
 	pvec->nr = j;
 }
 
@@ -567,6 +577,7 @@ invalidate_complete_page2(struct address_space *mapping, struct page *page)
 	if (page_has_private(page) && !try_to_release_page(page, GFP_KERNEL))
 		return 0;
 
+	spin_lock(&mapping->host->i_lock);
 	xa_lock_irq(&mapping->i_pages);
 	if (PageDirty(page))
 		goto failed;
@@ -574,6 +585,9 @@ invalidate_complete_page2(struct address_space *mapping, struct page *page)
 	BUG_ON(page_has_private(page));
 	__delete_from_page_cache(page, NULL);
 	xa_unlock_irq(&mapping->i_pages);
+	if (mapping_shrinkable(mapping))
+		inode_add_lru(mapping->host);
+	spin_unlock(&mapping->host->i_lock);
 
 	if (mapping->a_ops->freepage)
 		mapping->a_ops->freepage(page);
@@ -582,6 +596,7 @@ invalidate_complete_page2(struct address_space *mapping, struct page *page)
 	return 1;
 failed:
 	xa_unlock_irq(&mapping->i_pages);
+	spin_unlock(&mapping->host->i_lock);
 	return 0;
 }
 
diff --git a/mm/vmscan.c b/mm/vmscan.c
index ef4a6dc7f000..fb9584641ac7 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1205,6 +1205,8 @@ static int __remove_mapping(struct address_space *mapping, struct page *page,
 	BUG_ON(!PageLocked(page));
 	BUG_ON(mapping != page_mapping(page));
 
+	if (!PageSwapCache(page))
+		spin_lock(&mapping->host->i_lock);
 	xa_lock_irq(&mapping->i_pages);
 	/*
 	 * The non racy check for a busy page.
@@ -1273,6 +1275,9 @@ static int __remove_mapping(struct address_space *mapping, struct page *page,
 			shadow = workingset_eviction(page, target_memcg);
 		__delete_from_page_cache(page, shadow);
 		xa_unlock_irq(&mapping->i_pages);
+		if (mapping_shrinkable(mapping))
+			inode_add_lru(mapping->host);
+		spin_unlock(&mapping->host->i_lock);
 
 		if (freepage != NULL)
 			freepage(page);
@@ -1282,6 +1287,8 @@ static int __remove_mapping(struct address_space *mapping, struct page *page,
 
 cannot_free:
 	xa_unlock_irq(&mapping->i_pages);
+	if (!PageSwapCache(page))
+		spin_unlock(&mapping->host->i_lock);
 	return 0;
 }
 
diff --git a/mm/workingset.c b/mm/workingset.c
index 109ab978251a..8c03afe1d67c 100644
--- a/mm/workingset.c
+++ b/mm/workingset.c
@@ -543,6 +543,13 @@ static enum lru_status shadow_lru_isolate(struct list_head *item,
 		goto out;
 	}
 
+	if (!spin_trylock(&mapping->host->i_lock)) {
+		xa_unlock(&mapping->i_pages);
+		spin_unlock_irq(lru_lock);
+		ret = LRU_RETRY;
+		goto out;
+	}
+
 	list_lru_isolate(lru, item);
 	__dec_lruvec_kmem_state(node, WORKINGSET_NODES);
 
@@ -562,6 +569,9 @@ static enum lru_status shadow_lru_isolate(struct list_head *item,
 
 out_invalid:
 	xa_unlock_irq(&mapping->i_pages);
+	if (mapping_shrinkable(mapping))
+		inode_add_lru(mapping->host);
+	spin_unlock(&mapping->host->i_lock);
 	ret = LRU_REMOVED_RETRY;
 out:
 	cond_resched();