Merge branch 'akpm' (patches from Andrew)

Merge misc updates from Andrew Morton:
 "191 patches.

  Subsystems affected by this patch series: kthread, ia64, scripts,
  ntfs, squashfs, ocfs2, kernel/watchdog, and mm (gup, pagealloc, slab,
  slub, kmemleak, dax, debug, pagecache, gup, swap, memcg, pagemap,
  mprotect, bootmem, dma, tracing, vmalloc, kasan, initialization,
  pagealloc, and memory-failure)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (191 commits)
  mm,hwpoison: make get_hwpoison_page() call get_any_page()
  mm,hwpoison: send SIGBUS with error virutal address
  mm/page_alloc: split pcp->high across all online CPUs for cpuless nodes
  mm/page_alloc: allow high-order pages to be stored on the per-cpu lists
  mm: replace CONFIG_FLAT_NODE_MEM_MAP with CONFIG_FLATMEM
  mm: replace CONFIG_NEED_MULTIPLE_NODES with CONFIG_NUMA
  docs: remove description of DISCONTIGMEM
  arch, mm: remove stale mentions of DISCONIGMEM
  mm: remove CONFIG_DISCONTIGMEM
  m68k: remove support for DISCONTIGMEM
  arc: remove support for DISCONTIGMEM
  arc: update comment about HIGHMEM implementation
  alpha: remove DISCONTIGMEM and NUMA
  mm/page_alloc: move free_the_page
  mm/page_alloc: fix counting of managed_pages
  mm/page_alloc: improve memmap_pages dbg msg
  mm: drop SECTION_SHIFT in code comments
  mm/page_alloc: introduce vm.percpu_pagelist_high_fraction
  mm/page_alloc: limit the number of pages on PCP lists when reclaim is active
  mm/page_alloc: scale the number of pages that are batch freed
  ...

13 files changed, 141 insertions, 121 deletions

diff --git a/mm/kasan/Makefile b/mm/kasan/Makefile
index 9fe39a66388a..adcd9acaef61 100644
--- a/mm/kasan/Makefile
+++ b/mm/kasan/Makefile
@@ -37,5 +37,5 @@ CFLAGS_sw_tags.o := $(CC_FLAGS_KASAN_RUNTIME)
 
 obj-$(CONFIG_KASAN) := common.o report.o
 obj-$(CONFIG_KASAN_GENERIC) += init.o generic.o report_generic.o shadow.o quarantine.o
-obj-$(CONFIG_KASAN_HW_TAGS) += hw_tags.o report_hw_tags.o
-obj-$(CONFIG_KASAN_SW_TAGS) += init.o report_sw_tags.o shadow.o sw_tags.o
+obj-$(CONFIG_KASAN_HW_TAGS) += hw_tags.o report_hw_tags.o tags.o report_tags.o
+obj-$(CONFIG_KASAN_SW_TAGS) += init.o report_sw_tags.o shadow.o sw_tags.o tags.o report_tags.o
diff --git a/mm/kasan/common.c b/mm/kasan/common.c
index 0ecd293af344..2baf121fb8c5 100644
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -51,11 +51,14 @@ void kasan_enable_current(void)
 {
 	current->kasan_depth++;
 }
+EXPORT_SYMBOL(kasan_enable_current);
 
 void kasan_disable_current(void)
 {
 	current->kasan_depth--;
 }
+EXPORT_SYMBOL(kasan_disable_current);
+
 #endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
 
 void __kasan_unpoison_range(const void *address, size_t size)
@@ -328,6 +331,9 @@ static inline bool ____kasan_slab_free(struct kmem_cache *cache, void *object,
 	u8 tag;
 	void *tagged_object;
 
+	if (!kasan_arch_is_ready())
+		return false;
+
 	tag = get_tag(object);
 	tagged_object = object;
 	object = kasan_reset_tag(object);
diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c
index 53cbf28859b5..c3f5ba7a294a 100644
--- a/mm/kasan/generic.c
+++ b/mm/kasan/generic.c
@@ -163,6 +163,9 @@ static __always_inline bool check_region_inline(unsigned long addr,
 						size_t size, bool write,
 						unsigned long ret_ip)
 {
+	if (!kasan_arch_is_ready())
+		return true;
+
 	if (unlikely(size == 0))
 		return true;
 
diff --git a/mm/kasan/hw_tags.c b/mm/kasan/hw_tags.c
index ed5e5b833d61..4ea8c368b5b8 100644
--- a/mm/kasan/hw_tags.c
+++ b/mm/kasan/hw_tags.c
@@ -216,28 +216,6 @@ void __init kasan_init_hw_tags(void)
 	pr_info("KernelAddressSanitizer initialized\n");
 }
 
-void kasan_set_free_info(struct kmem_cache *cache,
-				void *object, u8 tag)
-{
-	struct kasan_alloc_meta *alloc_meta;
-
-	alloc_meta = kasan_get_alloc_meta(cache, object);
-	if (alloc_meta)
-		kasan_set_track(&alloc_meta->free_track[0], GFP_NOWAIT);
-}
-
-struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
-				void *object, u8 tag)
-{
-	struct kasan_alloc_meta *alloc_meta;
-
-	alloc_meta = kasan_get_alloc_meta(cache, object);
-	if (!alloc_meta)
-		return NULL;
-
-	return &alloc_meta->free_track[0];
-}
-
 void kasan_alloc_pages(struct page *page, unsigned int order, gfp_t flags)
 {
 	/*
diff --git a/mm/kasan/init.c b/mm/kasan/init.c
index 348f31d15a97..cc64ed6858c6 100644
--- a/mm/kasan/init.c
+++ b/mm/kasan/init.c
@@ -41,7 +41,7 @@ static inline bool kasan_p4d_table(pgd_t pgd)
 }
 #endif
 #if CONFIG_PGTABLE_LEVELS > 3
-pud_t kasan_early_shadow_pud[PTRS_PER_PUD] __page_aligned_bss;
+pud_t kasan_early_shadow_pud[MAX_PTRS_PER_PUD] __page_aligned_bss;
 static inline bool kasan_pud_table(p4d_t p4d)
 {
 	return p4d_page(p4d) == virt_to_page(lm_alias(kasan_early_shadow_pud));
@@ -53,7 +53,7 @@ static inline bool kasan_pud_table(p4d_t p4d)
 }
 #endif
 #if CONFIG_PGTABLE_LEVELS > 2
-pmd_t kasan_early_shadow_pmd[PTRS_PER_PMD] __page_aligned_bss;
+pmd_t kasan_early_shadow_pmd[MAX_PTRS_PER_PMD] __page_aligned_bss;
 static inline bool kasan_pmd_table(pud_t pud)
 {
 	return pud_page(pud) == virt_to_page(lm_alias(kasan_early_shadow_pmd));
@@ -64,7 +64,7 @@ static inline bool kasan_pmd_table(pud_t pud)
 	return false;
 }
 #endif
-pte_t kasan_early_shadow_pte[PTRS_PER_PTE + PTE_HWTABLE_PTRS]
+pte_t kasan_early_shadow_pte[MAX_PTRS_PER_PTE + PTE_HWTABLE_PTRS]
 	__page_aligned_bss;
 
 static inline bool kasan_pte_table(pmd_t pmd)
diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
index 8f450bc28045..98e3059bfea4 100644
--- a/mm/kasan/kasan.h
+++ b/mm/kasan/kasan.h
@@ -153,7 +153,7 @@ struct kasan_track {
 	depot_stack_handle_t stack;
 };
 
-#ifdef CONFIG_KASAN_SW_TAGS_IDENTIFY
+#if defined(CONFIG_KASAN_TAGS_IDENTIFY) && defined(CONFIG_KASAN_SW_TAGS)
 #define KASAN_NR_FREE_STACKS 5
 #else
 #define KASAN_NR_FREE_STACKS 1
@@ -170,7 +170,7 @@ struct kasan_alloc_meta {
 #else
 	struct kasan_track free_track[KASAN_NR_FREE_STACKS];
 #endif
-#ifdef CONFIG_KASAN_SW_TAGS_IDENTIFY
+#ifdef CONFIG_KASAN_TAGS_IDENTIFY
 	u8 free_pointer_tag[KASAN_NR_FREE_STACKS];
 	u8 free_track_idx;
 #endif
@@ -449,6 +449,12 @@ static inline void kasan_poison_last_granule(const void *address, size_t size) {
 
 #endif /* CONFIG_KASAN_GENERIC */
 
+#ifndef kasan_arch_is_ready
+static inline bool kasan_arch_is_ready(void)	{ return true; }
+#elif !defined(CONFIG_KASAN_GENERIC) || !defined(CONFIG_KASAN_OUTLINE)
+#error kasan_arch_is_ready only works in KASAN generic outline mode!
+#endif
+
 /*
  * Exported functions for interfaces called from assembly or from generated
  * code. Declarations here to avoid warning about missing declarations.
diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index 14bd51ea2348..8fff1825b22c 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -230,7 +230,7 @@ static void print_address_description(void *addr, u8 tag)
 {
 	struct page *page = kasan_addr_to_page(addr);
 
-	dump_stack();
+	dump_stack_lvl(KERN_ERR);
 	pr_err("\n");
 
 	if (page && PageSlab(page)) {
@@ -375,7 +375,7 @@ void kasan_report_async(void)
 	pr_err("BUG: KASAN: invalid-access\n");
 	pr_err("Asynchronous mode enabled: no access details available\n");
 	pr_err("\n");
-	dump_stack();
+	dump_stack_lvl(KERN_ERR);
 	end_report(&flags, 0);
 }
 #endif /* CONFIG_KASAN_HW_TAGS */
@@ -420,7 +420,7 @@ static void __kasan_report(unsigned long addr, size_t size, bool is_write,
 		pr_err("\n");
 		print_memory_metadata(info.first_bad_addr);
 	} else {
-		dump_stack();
+		dump_stack_lvl(KERN_ERR);
 	}
 
 	end_report(&flags, addr);
diff --git a/mm/kasan/report_hw_tags.c b/mm/kasan/report_hw_tags.c
index 42b2168755d6..5dbbbb930e7a 100644
--- a/mm/kasan/report_hw_tags.c
+++ b/mm/kasan/report_hw_tags.c
@@ -15,11 +15,6 @@
 
 #include "kasan.h"
 
-const char *kasan_get_bug_type(struct kasan_access_info *info)
-{
-	return "invalid-access";
-}
-
 void *kasan_find_first_bad_addr(void *addr, size_t size)
 {
 	return kasan_reset_tag(addr);
diff --git a/mm/kasan/report_sw_tags.c b/mm/kasan/report_sw_tags.c
index 3d20d3451d9e..d2298c357834 100644
--- a/mm/kasan/report_sw_tags.c
+++ b/mm/kasan/report_sw_tags.c
@@ -29,49 +29,6 @@
 #include "kasan.h"
 #include "../slab.h"
 
-const char *kasan_get_bug_type(struct kasan_access_info *info)
-{
-#ifdef CONFIG_KASAN_SW_TAGS_IDENTIFY
-	struct kasan_alloc_meta *alloc_meta;
-	struct kmem_cache *cache;
-	struct page *page;
-	const void *addr;
-	void *object;
-	u8 tag;
-	int i;
-
-	tag = get_tag(info->access_addr);
-	addr = kasan_reset_tag(info->access_addr);
-	page = kasan_addr_to_page(addr);
-	if (page && PageSlab(page)) {
-		cache = page->slab_cache;
-		object = nearest_obj(cache, page, (void *)addr);
-		alloc_meta = kasan_get_alloc_meta(cache, object);
-
-		if (alloc_meta) {
-			for (i = 0; i < KASAN_NR_FREE_STACKS; i++) {
-				if (alloc_meta->free_pointer_tag[i] == tag)
-					return "use-after-free";
-			}
-		}
-		return "out-of-bounds";
-	}
-
-#endif
-	/*
-	 * If access_size is a negative number, then it has reason to be
-	 * defined as out-of-bounds bug type.
-	 *
-	 * Casting negative numbers to size_t would indeed turn up as
-	 * a large size_t and its value will be larger than ULONG_MAX/2,
-	 * so that this can qualify as out-of-bounds.
-	 */
-	if (info->access_addr + info->access_size < info->access_addr)
-		return "out-of-bounds";
-
-	return "invalid-access";
-}
-
 void *kasan_find_first_bad_addr(void *addr, size_t size)
 {
 	u8 tag = get_tag(addr);
diff --git a/mm/kasan/report_tags.c b/mm/kasan/report_tags.c
new file mode 100644
index 000000000000..8a319fc16dab
--- /dev/null
+++ b/mm/kasan/report_tags.c
@@ -0,0 +1,51 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2014 Samsung Electronics Co., Ltd.
+ * Copyright (c) 2020 Google, Inc.
+ */
+
+#include "kasan.h"
+#include "../slab.h"
+
+const char *kasan_get_bug_type(struct kasan_access_info *info)
+{
+#ifdef CONFIG_KASAN_TAGS_IDENTIFY
+	struct kasan_alloc_meta *alloc_meta;
+	struct kmem_cache *cache;
+	struct page *page;
+	const void *addr;
+	void *object;
+	u8 tag;
+	int i;
+
+	tag = get_tag(info->access_addr);
+	addr = kasan_reset_tag(info->access_addr);
+	page = kasan_addr_to_page(addr);
+	if (page && PageSlab(page)) {
+		cache = page->slab_cache;
+		object = nearest_obj(cache, page, (void *)addr);
+		alloc_meta = kasan_get_alloc_meta(cache, object);
+
+		if (alloc_meta) {
+			for (i = 0; i < KASAN_NR_FREE_STACKS; i++) {
+				if (alloc_meta->free_pointer_tag[i] == tag)
+					return "use-after-free";
+			}
+		}
+		return "out-of-bounds";
+	}
+#endif
+
+	/*
+	 * If access_size is a negative number, then it has reason to be
+	 * defined as out-of-bounds bug type.
+	 *
+	 * Casting negative numbers to size_t would indeed turn up as
+	 * a large size_t and its value will be larger than ULONG_MAX/2,
+	 * so that this can qualify as out-of-bounds.
+	 */
+	if (info->access_addr + info->access_size < info->access_addr)
+		return "out-of-bounds";
+
+	return "invalid-access";
+}
diff --git a/mm/kasan/shadow.c b/mm/kasan/shadow.c
index 082ee5b6d9a1..8d95ee52d019 100644
--- a/mm/kasan/shadow.c
+++ b/mm/kasan/shadow.c
@@ -73,6 +73,9 @@ void kasan_poison(const void *addr, size_t size, u8 value, bool init)
 {
 	void *shadow_start, *shadow_end;
 
+	if (!kasan_arch_is_ready())
+		return;
+
 	/*
 	 * Perform shadow offset calculation based on untagged address, as
 	 * some of the callers (e.g. kasan_poison_object_data) pass tagged
@@ -99,6 +102,9 @@ EXPORT_SYMBOL(kasan_poison);
 #ifdef CONFIG_KASAN_GENERIC
 void kasan_poison_last_granule(const void *addr, size_t size)
 {
+	if (!kasan_arch_is_ready())
+		return;
+
 	if (size & KASAN_GRANULE_MASK) {
 		u8 *shadow = (u8 *)kasan_mem_to_shadow(addr + size);
 		*shadow = size & KASAN_GRANULE_MASK;
diff --git a/mm/kasan/sw_tags.c b/mm/kasan/sw_tags.c
index 9362938abbfa..bd3f540feb47 100644
--- a/mm/kasan/sw_tags.c
+++ b/mm/kasan/sw_tags.c
@@ -167,47 +167,6 @@ void __hwasan_tag_memory(unsigned long addr, u8 tag, unsigned long size)
 }
 EXPORT_SYMBOL(__hwasan_tag_memory);
 
-void kasan_set_free_info(struct kmem_cache *cache,
-				void *object, u8 tag)
-{
-	struct kasan_alloc_meta *alloc_meta;
-	u8 idx = 0;
-
-	alloc_meta = kasan_get_alloc_meta(cache, object);
-	if (!alloc_meta)
-		return;
-
-#ifdef CONFIG_KASAN_SW_TAGS_IDENTIFY
-	idx = alloc_meta->free_track_idx;
-	alloc_meta->free_pointer_tag[idx] = tag;
-	alloc_meta->free_track_idx = (idx + 1) % KASAN_NR_FREE_STACKS;
-#endif
-
-	kasan_set_track(&alloc_meta->free_track[idx], GFP_NOWAIT);
-}
-
-struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
-				void *object, u8 tag)
-{
-	struct kasan_alloc_meta *alloc_meta;
-	int i = 0;
-
-	alloc_meta = kasan_get_alloc_meta(cache, object);
-	if (!alloc_meta)
-		return NULL;
-
-#ifdef CONFIG_KASAN_SW_TAGS_IDENTIFY
-	for (i = 0; i < KASAN_NR_FREE_STACKS; i++) {
-		if (alloc_meta->free_pointer_tag[i] == tag)
-			break;
-	}
-	if (i == KASAN_NR_FREE_STACKS)
-		i = alloc_meta->free_track_idx;
-#endif
-
-	return &alloc_meta->free_track[i];
-}
-
 void kasan_tag_mismatch(unsigned long addr, unsigned long access_info,
 			unsigned long ret_ip)
 {
diff --git a/mm/kasan/tags.c b/mm/kasan/tags.c
new file mode 100644
index 000000000000..8f48b9502a17
--- /dev/null
+++ b/mm/kasan/tags.c
@@ -0,0 +1,59 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * This file contains common tag-based KASAN code.
+ *
+ * Copyright (c) 2018 Google, Inc.
+ * Copyright (c) 2020 Google, Inc.
+ */
+
+#include <linux/init.h>
+#include <linux/kasan.h>
+#include <linux/kernel.h>
+#include <linux/memory.h>
+#include <linux/mm.h>
+#include <linux/static_key.h>
+#include <linux/string.h>
+#include <linux/types.h>
+
+#include "kasan.h"
+
+void kasan_set_free_info(struct kmem_cache *cache,
+				void *object, u8 tag)
+{
+	struct kasan_alloc_meta *alloc_meta;
+	u8 idx = 0;
+
+	alloc_meta = kasan_get_alloc_meta(cache, object);
+	if (!alloc_meta)
+		return;
+
+#ifdef CONFIG_KASAN_TAGS_IDENTIFY
+	idx = alloc_meta->free_track_idx;
+	alloc_meta->free_pointer_tag[idx] = tag;
+	alloc_meta->free_track_idx = (idx + 1) % KASAN_NR_FREE_STACKS;
+#endif
+
+	kasan_set_track(&alloc_meta->free_track[idx], GFP_NOWAIT);
+}
+
+struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
+				void *object, u8 tag)
+{
+	struct kasan_alloc_meta *alloc_meta;
+	int i = 0;
+
+	alloc_meta = kasan_get_alloc_meta(cache, object);
+	if (!alloc_meta)
+		return NULL;
+
+#ifdef CONFIG_KASAN_TAGS_IDENTIFY
+	for (i = 0; i < KASAN_NR_FREE_STACKS; i++) {
+		if (alloc_meta->free_pointer_tag[i] == tag)
+			break;
+	}
+	if (i == KASAN_NR_FREE_STACKS)
+		i = alloc_meta->free_track_idx;
+#endif
+
+	return &alloc_meta->free_track[i];
+}