Merge branch 'akpm' (patches from Andrew)

Merge misc updates from Andrew Morton:
 "257 patches.

  Subsystems affected by this patch series: scripts, ocfs2, vfs, and
  mm (slab-generic, slab, slub, kconfig, dax, kasan, debug, pagecache,
  gup, swap, memcg, pagemap, mprotect, mremap, iomap, tracing, vmalloc,
  pagealloc, memory-failure, hugetlb, userfaultfd, vmscan, tools,
  memblock, oom-kill, hugetlbfs, migration, thp, readahead, nommu, ksm,
  vmstat, madvise, memory-hotplug, rmap, zsmalloc, highmem, zram,
  cleanups, kfence, and damon)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (257 commits)
  mm/damon: remove return value from before_terminate callback
  mm/damon: fix a few spelling mistakes in comments and a pr_debug message
  mm/damon: simplify stop mechanism
  Docs/admin-guide/mm/pagemap: wordsmith page flags descriptions
  Docs/admin-guide/mm/damon/start: simplify the content
  Docs/admin-guide/mm/damon/start: fix a wrong link
  Docs/admin-guide/mm/damon/start: fix wrong example commands
  mm/damon/dbgfs: add adaptive_targets list check before enable monitor_on
  mm/damon: remove unnecessary variable initialization
  Documentation/admin-guide/mm/damon: add a document for DAMON_RECLAIM
  mm/damon: introduce DAMON-based Reclamation (DAMON_RECLAIM)
  selftests/damon: support watermarks
  mm/damon/dbgfs: support watermarks
  mm/damon/schemes: activate schemes based on a watermarks mechanism
  tools/selftests/damon: update for regions prioritization of schemes
  mm/damon/dbgfs: support prioritization weights
  mm/damon/vaddr,paddr: support pageout prioritization
  mm/damon/schemes: prioritize regions within the quotas
  mm/damon/selftests: support schemes quotas
  mm/damon/dbgfs: support quotas of schemes
  ...

8 files changed, 85 insertions, 53 deletions

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 6fdbf9613aec..9ef7ce18b4f5 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -877,7 +877,7 @@ config DEBUG_MEMORY_INIT
 
 config MEMORY_NOTIFIER_ERROR_INJECT
 	tristate "Memory hotplug notifier error injection module"
-	depends on MEMORY_HOTPLUG_SPARSE && NOTIFIER_ERROR_INJECTION
+	depends on MEMORY_HOTPLUG && NOTIFIER_ERROR_INJECTION
 	help
 	  This option provides the ability to inject artificial errors to
 	  memory hotplug notifier chain callbacks.  It is controlled through
diff --git a/lib/Kconfig.kfence b/lib/Kconfig.kfence
index e641add33947..912f252a41fc 100644
--- a/lib/Kconfig.kfence
+++ b/lib/Kconfig.kfence
@@ -25,17 +25,6 @@ menuconfig KFENCE
 
 if KFENCE
 
-config KFENCE_STATIC_KEYS
-	bool "Use static keys to set up allocations"
-	default y
-	depends on JUMP_LABEL # To ensure performance, require jump labels
-	help
-	  Use static keys (static branches) to set up KFENCE allocations. Using
-	  static keys is normally recommended, because it avoids a dynamic
-	  branch in the allocator's fast path. However, with very low sample
-	  intervals, or on systems that do not support jump labels, a dynamic
-	  branch may still be an acceptable performance trade-off.
-
 config KFENCE_SAMPLE_INTERVAL
 	int "Default sample interval in milliseconds"
 	default 100
@@ -56,6 +45,21 @@ config KFENCE_NUM_OBJECTS
 	  pages are required; with one containing the object and two adjacent
 	  ones used as guard pages.
 
+config KFENCE_STATIC_KEYS
+	bool "Use static keys to set up allocations" if EXPERT
+	depends on JUMP_LABEL
+	help
+	  Use static keys (static branches) to set up KFENCE allocations. This
+	  option is only recommended when using very large sample intervals, or
+	  performance has carefully been evaluated with this option.
+
+	  Using static keys comes with trade-offs that need to be carefully
+	  evaluated given target workloads and system architectures. Notably,
+	  enabling and disabling static keys invoke IPI broadcasts, the latency
+	  and impact of which is much harder to predict than a dynamic branch.
+
+	  Say N if you are unsure.
+
 config KFENCE_STRESS_TEST_FAULTS
 	int "Stress testing of fault handling and error reporting" if EXPERT
 	default 0
diff --git a/lib/bootconfig.c b/lib/bootconfig.c
index 70e0d52ffd24..74f3201ab8e5 100644
--- a/lib/bootconfig.c
+++ b/lib/bootconfig.c
@@ -50,7 +50,7 @@ static inline void * __init xbc_alloc_mem(size_t size)
 
 static inline void __init xbc_free_mem(void *addr, size_t size)
 {
-	memblock_free_ptr(addr, size);
+	memblock_free(addr, size);
 }
 
 #else /* !__KERNEL__ */
diff --git a/lib/cpumask.c b/lib/cpumask.c
index c3c76b833384..a971a82d2f43 100644
--- a/lib/cpumask.c
+++ b/lib/cpumask.c
@@ -188,7 +188,7 @@ EXPORT_SYMBOL(free_cpumask_var);
  */
 void __init free_bootmem_cpumask_var(cpumask_var_t mask)
 {
-	memblock_free_early(__pa(mask), cpumask_size());
+	memblock_free(mask, cpumask_size());
 }
 #endif
 
diff --git a/lib/stackdepot.c b/lib/stackdepot.c
index 0a2e417f83cb..09485dc5bd12 100644
--- a/lib/stackdepot.c
+++ b/lib/stackdepot.c
@@ -20,7 +20,6 @@
  */
 
 #include <linux/gfp.h>
-#include <linux/interrupt.h>
 #include <linux/jhash.h>
 #include <linux/kernel.h>
 #include <linux/mm.h>
@@ -102,8 +101,8 @@ static bool init_stack_slab(void **prealloc)
 }
 
 /* Allocation of a new stack in raw storage */
-static struct stack_record *depot_alloc_stack(unsigned long *entries, int size,
-		u32 hash, void **prealloc, gfp_t alloc_flags)
+static struct stack_record *
+depot_alloc_stack(unsigned long *entries, int size, u32 hash, void **prealloc)
 {
 	struct stack_record *stack;
 	size_t required_size = struct_size(stack, entries, size);
@@ -248,17 +247,28 @@ unsigned int stack_depot_fetch(depot_stack_handle_t handle,
 EXPORT_SYMBOL_GPL(stack_depot_fetch);
 
 /**
- * stack_depot_save - Save a stack trace from an array
+ * __stack_depot_save - Save a stack trace from an array
  *
  * @entries:		Pointer to storage array
  * @nr_entries:		Size of the storage array
  * @alloc_flags:	Allocation gfp flags
+ * @can_alloc:		Allocate stack slabs (increased chance of failure if false)
+ *
+ * Saves a stack trace from @entries array of size @nr_entries. If @can_alloc is
+ * %true, is allowed to replenish the stack slab pool in case no space is left
+ * (allocates using GFP flags of @alloc_flags). If @can_alloc is %false, avoids
+ * any allocations and will fail if no space is left to store the stack trace.
  *
- * Return: The handle of the stack struct stored in depot
+ * Context: Any context, but setting @can_alloc to %false is required if
+ *          alloc_pages() cannot be used from the current context. Currently
+ *          this is the case from contexts where neither %GFP_ATOMIC nor
+ *          %GFP_NOWAIT can be used (NMI, raw_spin_lock).
+ *
+ * Return: The handle of the stack struct stored in depot, 0 on failure.
  */
-depot_stack_handle_t stack_depot_save(unsigned long *entries,
-				      unsigned int nr_entries,
-				      gfp_t alloc_flags)
+depot_stack_handle_t __stack_depot_save(unsigned long *entries,
+					unsigned int nr_entries,
+					gfp_t alloc_flags, bool can_alloc)
 {
 	struct stack_record *found = NULL, **bucket;
 	depot_stack_handle_t retval = 0;
@@ -291,7 +301,7 @@ depot_stack_handle_t stack_depot_save(unsigned long *entries,
 	 * The smp_load_acquire() here pairs with smp_store_release() to
 	 * |next_slab_inited| in depot_alloc_stack() and init_stack_slab().
 	 */
-	if (unlikely(!smp_load_acquire(&next_slab_inited))) {
+	if (unlikely(can_alloc && !smp_load_acquire(&next_slab_inited))) {
 		/*
 		 * Zero out zone modifiers, as we don't have specific zone
 		 * requirements. Keep the flags related to allocation in atomic
@@ -309,9 +319,8 @@ depot_stack_handle_t stack_depot_save(unsigned long *entries,
 
 	found = find_stack(*bucket, entries, nr_entries, hash);
 	if (!found) {
-		struct stack_record *new =
-			depot_alloc_stack(entries, nr_entries,
-					  hash, &prealloc, alloc_flags);
+		struct stack_record *new = depot_alloc_stack(entries, nr_entries, hash, &prealloc);
+
 		if (new) {
 			new->next = *bucket;
 			/*
@@ -340,27 +349,24 @@ exit:
 fast_exit:
 	return retval;
 }
-EXPORT_SYMBOL_GPL(stack_depot_save);
-
-static inline int in_irqentry_text(unsigned long ptr)
-{
-	return (ptr >= (unsigned long)&__irqentry_text_start &&
-		ptr < (unsigned long)&__irqentry_text_end) ||
-		(ptr >= (unsigned long)&__softirqentry_text_start &&
-		 ptr < (unsigned long)&__softirqentry_text_end);
-}
+EXPORT_SYMBOL_GPL(__stack_depot_save);
 
-unsigned int filter_irq_stacks(unsigned long *entries,
-					     unsigned int nr_entries)
+/**
+ * stack_depot_save - Save a stack trace from an array
+ *
+ * @entries:		Pointer to storage array
+ * @nr_entries:		Size of the storage array
+ * @alloc_flags:	Allocation gfp flags
+ *
+ * Context: Contexts where allocations via alloc_pages() are allowed.
+ *          See __stack_depot_save() for more details.
+ *
+ * Return: The handle of the stack struct stored in depot, 0 on failure.
+ */
+depot_stack_handle_t stack_depot_save(unsigned long *entries,
+				      unsigned int nr_entries,
+				      gfp_t alloc_flags)
 {
-	unsigned int i;
-
-	for (i = 0; i < nr_entries; i++) {
-		if (in_irqentry_text(entries[i])) {
-			/* Include the irqentry function into the stack. */
-			return i + 1;
-		}
-	}
-	return nr_entries;
+	return __stack_depot_save(entries, nr_entries, alloc_flags, true);
 }
-EXPORT_SYMBOL_GPL(filter_irq_stacks);
+EXPORT_SYMBOL_GPL(stack_depot_save);
diff --git a/lib/test_kasan.c b/lib/test_kasan.c
index ebed755ebf34..67ed689a0b1b 100644
--- a/lib/test_kasan.c
+++ b/lib/test_kasan.c
@@ -440,6 +440,7 @@ static void kmalloc_oob_memset_2(struct kunit *test)
 	ptr = kmalloc(size, GFP_KERNEL);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
 
+	OPTIMIZER_HIDE_VAR(size);
 	KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr + size - 1, 0, 2));
 	kfree(ptr);
 }
@@ -452,6 +453,7 @@ static void kmalloc_oob_memset_4(struct kunit *test)
 	ptr = kmalloc(size, GFP_KERNEL);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
 
+	OPTIMIZER_HIDE_VAR(size);
 	KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr + size - 3, 0, 4));
 	kfree(ptr);
 }
@@ -464,6 +466,7 @@ static void kmalloc_oob_memset_8(struct kunit *test)
 	ptr = kmalloc(size, GFP_KERNEL);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
 
+	OPTIMIZER_HIDE_VAR(size);
 	KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr + size - 7, 0, 8));
 	kfree(ptr);
 }
@@ -476,6 +479,7 @@ static void kmalloc_oob_memset_16(struct kunit *test)
 	ptr = kmalloc(size, GFP_KERNEL);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
 
+	OPTIMIZER_HIDE_VAR(size);
 	KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr + size - 15, 0, 16));
 	kfree(ptr);
 }
@@ -488,16 +492,17 @@ static void kmalloc_oob_in_memset(struct kunit *test)
 	ptr = kmalloc(size, GFP_KERNEL);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
 
+	OPTIMIZER_HIDE_VAR(size);
 	KUNIT_EXPECT_KASAN_FAIL(test,
 				memset(ptr, 0, size + KASAN_GRANULE_SIZE));
 	kfree(ptr);
 }
 
-static void kmalloc_memmove_invalid_size(struct kunit *test)
+static void kmalloc_memmove_negative_size(struct kunit *test)
 {
 	char *ptr;
 	size_t size = 64;
-	volatile size_t invalid_size = -2;
+	size_t invalid_size = -2;
 
 	/*
 	 * Hardware tag-based mode doesn't check memmove for negative size.
@@ -510,6 +515,22 @@ static void kmalloc_memmove_invalid_size(struct kunit *test)
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
 
 	memset((char *)ptr, 0, 64);
+	OPTIMIZER_HIDE_VAR(invalid_size);
+	KUNIT_EXPECT_KASAN_FAIL(test,
+		memmove((char *)ptr, (char *)ptr + 4, invalid_size));
+	kfree(ptr);
+}
+
+static void kmalloc_memmove_invalid_size(struct kunit *test)
+{
+	char *ptr;
+	size_t size = 64;
+	volatile size_t invalid_size = size;
+
+	ptr = kmalloc(size, GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
+
+	memset((char *)ptr, 0, 64);
 	KUNIT_EXPECT_KASAN_FAIL(test,
 		memmove((char *)ptr, (char *)ptr + 4, invalid_size));
 	kfree(ptr);
@@ -1129,6 +1150,7 @@ static struct kunit_case kasan_kunit_test_cases[] = {
 	KUNIT_CASE(kmalloc_oob_memset_4),
 	KUNIT_CASE(kmalloc_oob_memset_8),
 	KUNIT_CASE(kmalloc_oob_memset_16),
+	KUNIT_CASE(kmalloc_memmove_negative_size),
 	KUNIT_CASE(kmalloc_memmove_invalid_size),
 	KUNIT_CASE(kmalloc_uaf),
 	KUNIT_CASE(kmalloc_uaf_memset),
diff --git a/lib/test_kasan_module.c b/lib/test_kasan_module.c
index 7ebf433edef3..b112cbc835e9 100644
--- a/lib/test_kasan_module.c
+++ b/lib/test_kasan_module.c
@@ -35,6 +35,8 @@ static noinline void __init copy_user_test(void)
 		return;
 	}
 
+	OPTIMIZER_HIDE_VAR(size);
+
 	pr_info("out-of-bounds in copy_from_user()\n");
 	unused = copy_from_user(kmem, usermem, size + 1);
 
diff --git a/lib/test_vmalloc.c b/lib/test_vmalloc.c
index e14993bc84d2..cf41fd6df42a 100644
--- a/lib/test_vmalloc.c
+++ b/lib/test_vmalloc.c
@@ -393,7 +393,7 @@ static struct test_driver {
 static void shuffle_array(int *arr, int n)
 {
 	unsigned int rnd;
-	int i, j, x;
+	int i, j;
 
 	for (i = n - 1; i > 0; i--)  {
 		get_random_bytes(&rnd, sizeof(rnd));
@@ -402,9 +402,7 @@ static void shuffle_array(int *arr, int n)
 		j = rnd % i;
 
 		/* Swap indexes. */
-		x = arr[i];
-		arr[i] = arr[j];
-		arr[j] = x;
+		swap(arr[i], arr[j]);
 	}
 }