28 files changed, 914 insertions, 177 deletions
diff --git a/lib/842/842_compress.c b/lib/842/842_compress.c
index c02baa4168e1..055356508d97 100644
--- a/lib/842/842_compress.c
+++ b/lib/842/842_compress.c
@@ -532,6 +532,8 @@ int sw842_compress(const u8 *in, unsigned int ilen,
 		}
 		if (repeat_count) {
 			ret = add_repeat_template(p, repeat_count);
+			if (ret)
+				return ret;
 			repeat_count = 0;
 			if (next == last) /* reached max repeat bits */
 				goto repeat;
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 8fb1d685f696..df9587aa5c5e 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1280,6 +1280,17 @@ config BOOTPARAM_HUNG_TASK_PANIC
 
 	  Say N if unsure.
 
+config DETECT_HUNG_TASK_BLOCKER
+	bool "Dump Hung Tasks Blocker"
+	depends on DETECT_HUNG_TASK
+	depends on !PREEMPT_RT
+	default y
+	help
+	  Say Y here to show the blocker task's stacktrace who acquires
+	  the mutex lock which "hung tasks" are waiting.
+	  This will add overhead a bit but shows suspicious tasks and
+	  call trace if it comes from waiting a mutex.
+
 config WQ_WATCHDOG
 	bool "Detect Workqueue Stalls"
 	depends on DEBUG_KERNEL
@@ -2502,13 +2513,20 @@ config TEST_IDA
 	tristate "Perform selftest on IDA functions"
 
 config TEST_MISC_MINOR
-	tristate "Basic misc minor Kunit test" if !KUNIT_ALL_TESTS
+	tristate "miscdevice KUnit test" if !KUNIT_ALL_TESTS
 	depends on KUNIT
 	default KUNIT_ALL_TESTS
 	help
-	  Kunit test for the misc minor.
-	  It tests misc minor functions for dynamic and misc dynamic minor.
-	  This include misc_xxx functions
+	  Kunit test for miscdevice API, specially its behavior in respect to
+	  static and dynamic minor numbers.
+
+	  KUnit tests run during boot and output the results to the debug log
+	  in TAP format (https://testanything.org/). Only useful for kernel devs
+	  running the KUnit test harness, and not intended for inclusion into a
+	  production build.
+
+	  For more information on KUnit and unit tests in general please refer
+	  to the KUnit documentation in Documentation/dev-tools/kunit/.
 
 	  If unsure, say N.
 
@@ -2866,6 +2884,15 @@ config FORTIFY_KUNIT_TEST
 	  by the str*() and mem*() family of functions. For testing runtime
 	  traps of FORTIFY_SOURCE, see LKDTM's "FORTIFY_*" tests.
 
+config LONGEST_SYM_KUNIT_TEST
+	tristate "Test the longest symbol possible" if !KUNIT_ALL_TESTS
+	depends on KUNIT && KPROBES
+	default KUNIT_ALL_TESTS
+	help
+	  Tests the longest symbol possible
+
+	  If unsure, say N.
+
 config HW_BREAKPOINT_KUNIT_TEST
 	bool "Test hw_breakpoint constraints accounting" if !KUNIT_ALL_TESTS
 	depends on HAVE_HW_BREAKPOINT
diff --git a/lib/alloc_tag.c b/lib/alloc_tag.c
index 19b45617bdcf..1d893e313614 100644
--- a/lib/alloc_tag.c
+++ b/lib/alloc_tag.c
@@ -174,7 +174,7 @@ void pgalloc_tag_split(struct folio *folio, int old_order, int new_order)
 	if (!mem_alloc_profiling_enabled())
 		return;
 
-	tag = pgalloc_tag_get(&folio->page);
+	tag = __pgalloc_tag_get(&folio->page);
 	if (!tag)
 		return;
 
@@ -200,10 +200,10 @@ void pgalloc_tag_swap(struct folio *new, struct folio *old)
 	if (!mem_alloc_profiling_enabled())
 		return;
 
-	tag_old = pgalloc_tag_get(&old->page);
+	tag_old = __pgalloc_tag_get(&old->page);
 	if (!tag_old)
 		return;
-	tag_new = pgalloc_tag_get(&new->page);
+	tag_new = __pgalloc_tag_get(&new->page);
 	if (!tag_new)
 		return;
 
diff --git a/lib/bug.c b/lib/bug.c
index e0ff21989990..b1f07459c2ee 100644
--- a/lib/bug.c
+++ b/lib/bug.c
@@ -66,23 +66,19 @@ static LIST_HEAD(module_bug_list);
 
 static struct bug_entry *module_find_bug(unsigned long bugaddr)
 {
+	struct bug_entry *bug;
 	struct module *mod;
-	struct bug_entry *bug = NULL;
 
-	rcu_read_lock_sched();
+	guard(rcu)();
 	list_for_each_entry_rcu(mod, &module_bug_list, bug_list) {
 		unsigned i;
 
 		bug = mod->bug_table;
 		for (i = 0; i < mod->num_bugs; ++i, ++bug)
 			if (bugaddr == bug_addr(bug))
-				goto out;
+				return bug;
 	}
-	bug = NULL;
-out:
-	rcu_read_unlock_sched();
-
-	return bug;
+	return NULL;
 }
 
 void module_bug_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
@@ -235,11 +231,11 @@ void generic_bug_clear_once(void)
 #ifdef CONFIG_MODULES
 	struct module *mod;
 
-	rcu_read_lock_sched();
-	list_for_each_entry_rcu(mod, &module_bug_list, bug_list)
-		clear_once_table(mod->bug_table,
-				 mod->bug_table + mod->num_bugs);
-	rcu_read_unlock_sched();
+	scoped_guard(rcu) {
+		list_for_each_entry_rcu(mod, &module_bug_list, bug_list)
+			clear_once_table(mod->bug_table,
+					 mod->bug_table + mod->num_bugs);
+	}
 #endif
 
 	clear_once_table(__start___bug_table, __stop___bug_table);
diff --git a/lib/crypto/Kconfig b/lib/crypto/Kconfig
index b01253cac70a..798972b29b68 100644
--- a/lib/crypto/Kconfig
+++ b/lib/crypto/Kconfig
@@ -42,7 +42,7 @@ config CRYPTO_LIB_BLAKE2S_GENERIC
 	  of CRYPTO_LIB_BLAKE2S.
 
 config CRYPTO_ARCH_HAVE_LIB_CHACHA
-	tristate
+	bool
 	help
 	  Declares whether the architecture provides an arch-specific
 	  accelerated implementation of the ChaCha library interface,
@@ -58,17 +58,21 @@ config CRYPTO_LIB_CHACHA_GENERIC
 	  implementation is enabled, this implementation serves the users
 	  of CRYPTO_LIB_CHACHA.
 
-config CRYPTO_LIB_CHACHA
-	tristate "ChaCha library interface"
-	depends on CRYPTO_ARCH_HAVE_LIB_CHACHA || !CRYPTO_ARCH_HAVE_LIB_CHACHA
+config CRYPTO_LIB_CHACHA_INTERNAL
+	tristate
 	select CRYPTO_LIB_CHACHA_GENERIC if CRYPTO_ARCH_HAVE_LIB_CHACHA=n
+
+config CRYPTO_LIB_CHACHA
+	tristate
+	select CRYPTO
+	select CRYPTO_LIB_CHACHA_INTERNAL
 	help
 	  Enable the ChaCha library interface. This interface may be fulfilled
 	  by either the generic implementation or an arch-specific one, if one
 	  is available and enabled.
 
 config CRYPTO_ARCH_HAVE_LIB_CURVE25519
-	tristate
+	bool
 	help
 	  Declares whether the architecture provides an arch-specific
 	  accelerated implementation of the Curve25519 library interface,
@@ -76,6 +80,7 @@ config CRYPTO_ARCH_HAVE_LIB_CURVE25519
 
 config CRYPTO_LIB_CURVE25519_GENERIC
 	tristate
+	select CRYPTO_LIB_UTILS
 	help
 	  This symbol can be depended upon by arch implementations of the
 	  Curve25519 library interface that require the generic code as a
@@ -83,11 +88,14 @@ config CRYPTO_LIB_CURVE25519_GENERIC
 	  implementation is enabled, this implementation serves the users
 	  of CRYPTO_LIB_CURVE25519.
 
-config CRYPTO_LIB_CURVE25519
-	tristate "Curve25519 scalar multiplication library"
-	depends on CRYPTO_ARCH_HAVE_LIB_CURVE25519 || !CRYPTO_ARCH_HAVE_LIB_CURVE25519
+config CRYPTO_LIB_CURVE25519_INTERNAL
+	tristate
 	select CRYPTO_LIB_CURVE25519_GENERIC if CRYPTO_ARCH_HAVE_LIB_CURVE25519=n
-	select CRYPTO_LIB_UTILS
+
+config CRYPTO_LIB_CURVE25519
+	tristate
+	select CRYPTO
+	select CRYPTO_LIB_CURVE25519_INTERNAL
 	help
 	  Enable the Curve25519 library interface. This interface may be
 	  fulfilled by either the generic implementation or an arch-specific
@@ -104,7 +112,7 @@ config CRYPTO_LIB_POLY1305_RSIZE
 	default 1
 
 config CRYPTO_ARCH_HAVE_LIB_POLY1305
-	tristate
+	bool
 	help
 	  Declares whether the architecture provides an arch-specific
 	  accelerated implementation of the Poly1305 library interface,
@@ -119,23 +127,24 @@ config CRYPTO_LIB_POLY1305_GENERIC
 	  implementation is enabled, this implementation serves the users
 	  of CRYPTO_LIB_POLY1305.
 
-config CRYPTO_LIB_POLY1305
-	tristate "Poly1305 library interface"
-	depends on CRYPTO_ARCH_HAVE_LIB_POLY1305 || !CRYPTO_ARCH_HAVE_LIB_POLY1305
+config CRYPTO_LIB_POLY1305_INTERNAL
+	tristate
 	select CRYPTO_LIB_POLY1305_GENERIC if CRYPTO_ARCH_HAVE_LIB_POLY1305=n
+
+config CRYPTO_LIB_POLY1305
+	tristate
+	select CRYPTO
+	select CRYPTO_LIB_POLY1305_INTERNAL
 	help
 	  Enable the Poly1305 library interface. This interface may be fulfilled
 	  by either the generic implementation or an arch-specific one, if one
 	  is available and enabled.
 
 config CRYPTO_LIB_CHACHA20POLY1305
-	tristate "ChaCha20-Poly1305 AEAD support (8-byte nonce library version)"
-	depends on CRYPTO_ARCH_HAVE_LIB_CHACHA || !CRYPTO_ARCH_HAVE_LIB_CHACHA
-	depends on CRYPTO_ARCH_HAVE_LIB_POLY1305 || !CRYPTO_ARCH_HAVE_LIB_POLY1305
-	depends on CRYPTO
+	tristate
 	select CRYPTO_LIB_CHACHA
 	select CRYPTO_LIB_POLY1305
-	select CRYPTO_ALGAPI
+	select CRYPTO_LIB_UTILS
 
 config CRYPTO_LIB_SHA1
 	tristate
diff --git a/lib/crypto/chacha20poly1305.c b/lib/crypto/chacha20poly1305.c
index a839c0ac60b2..9cfa886f1f89 100644
--- a/lib/crypto/chacha20poly1305.c
+++ b/lib/crypto/chacha20poly1305.c
@@ -7,11 +7,10 @@
  * Information: https://tools.ietf.org/html/rfc8439
  */
 
-#include <crypto/algapi.h>
 #include <crypto/chacha20poly1305.h>
 #include <crypto/chacha.h>
 #include <crypto/poly1305.h>
-#include <crypto/scatterwalk.h>
+#include <crypto/utils.h>
 
 #include <linux/unaligned.h>
 #include <linux/kernel.h>
@@ -318,8 +317,8 @@ bool chacha20poly1305_crypt_sg_inplace(struct scatterlist *src,
 
 	if (unlikely(sl > -POLY1305_DIGEST_SIZE)) {
 		poly1305_final(&poly1305_state, b.mac[1]);
-		scatterwalk_map_and_copy(b.mac[encrypt], src, src_len,
-					 sizeof(b.mac[1]), encrypt);
+		sg_copy_buffer(src, sg_nents(src), b.mac[encrypt],
+			       sizeof(b.mac[1]), src_len, !encrypt);
 		ret = encrypt ||
 		      !crypto_memneq(b.mac[0], b.mac[1], POLY1305_DIGEST_SIZE);
 	}
diff --git a/lib/idr.c b/lib/idr.c
index da36054c3ca0..e2adc457abb4 100644
--- a/lib/idr.c
+++ b/lib/idr.c
@@ -477,6 +477,73 @@ nospc:
 EXPORT_SYMBOL(ida_alloc_range);
 
 /**
+ * ida_find_first_range - Get the lowest used ID.
+ * @ida: IDA handle.
+ * @min: Lowest ID to get.
+ * @max: Highest ID to get.
+ *
+ * Get the lowest used ID between @min and @max, inclusive.  The returned
+ * ID will not exceed %INT_MAX, even if @max is larger.
+ *
+ * Context: Any context. Takes and releases the xa_lock.
+ * Return: The lowest used ID, or errno if no used ID is found.
+ */
+int ida_find_first_range(struct ida *ida, unsigned int min, unsigned int max)
+{
+	unsigned long index = min / IDA_BITMAP_BITS;
+	unsigned int offset = min % IDA_BITMAP_BITS;
+	unsigned long *addr, size, bit;
+	unsigned long tmp = 0;
+	unsigned long flags;
+	void *entry;
+	int ret;
+
+	if ((int)min < 0)
+		return -EINVAL;
+	if ((int)max < 0)
+		max = INT_MAX;
+
+	xa_lock_irqsave(&ida->xa, flags);
+
+	entry = xa_find(&ida->xa, &index, max / IDA_BITMAP_BITS, XA_PRESENT);
+	if (!entry) {
+		ret = -ENOENT;
+		goto err_unlock;
+	}
+
+	if (index > min / IDA_BITMAP_BITS)
+		offset = 0;
+	if (index * IDA_BITMAP_BITS + offset > max) {
+		ret = -ENOENT;
+		goto err_unlock;
+	}
+
+	if (xa_is_value(entry)) {
+		tmp = xa_to_value(entry);
+		addr = &tmp;
+		size = BITS_PER_XA_VALUE;
+	} else {
+		addr = ((struct ida_bitmap *)entry)->bitmap;
+		size = IDA_BITMAP_BITS;
+	}
+
+	bit = find_next_bit(addr, size, offset);
+
+	xa_unlock_irqrestore(&ida->xa, flags);
+
+	if (bit == size ||
+	    index * IDA_BITMAP_BITS + bit > max)
+		return -ENOENT;
+
+	return index * IDA_BITMAP_BITS + bit;
+
+err_unlock:
+	xa_unlock_irqrestore(&ida->xa, flags);
+	return ret;
+}
+EXPORT_SYMBOL(ida_find_first_range);
+
+/**
  * ida_free() - Release an allocated ID.
  * @ida: IDA handle.
  * @id: Previously allocated ID.
diff --git a/lib/interval_tree.c b/lib/interval_tree.c
index 3412737ff365..324766e9bf63 100644
--- a/lib/interval_tree.c
+++ b/lib/interval_tree.c
@@ -20,9 +20,15 @@ EXPORT_SYMBOL_GPL(interval_tree_iter_next);
 /*
  * Roll nodes[1] into nodes[0] by advancing nodes[1] to the end of a contiguous
  * span of nodes. This makes nodes[0]->last the end of that contiguous used span
- * indexes that started at the original nodes[1]->start. nodes[1] is now the
- * first node starting the next used span. A hole span is between nodes[0]->last
- * and nodes[1]->start. nodes[1] must be !NULL.
+ * of indexes that started at the original nodes[1]->start.
+ *
+ * If there is an interior hole, nodes[1] is now the first node starting the
+ * next used span. A hole span is between nodes[0]->last and nodes[1]->start.
+ *
+ * If there is a tailing hole, nodes[1] is now NULL. A hole span is between
+ * nodes[0]->last and last_index.
+ *
+ * If the contiguous used range span to last_index, nodes[1] is set to NULL.
  */
 static void
 interval_tree_span_iter_next_gap(struct interval_tree_span_iter *state)
diff --git a/lib/interval_tree_test.c b/lib/interval_tree_test.c
index 837064b83a6c..5fd62656f42e 100644
--- a/lib/interval_tree_test.c
+++ b/lib/interval_tree_test.c
@@ -5,6 +5,8 @@
 #include <linux/prandom.h>
 #include <linux/slab.h>
 #include <asm/timex.h>
+#include <linux/bitmap.h>
+#include <linux/maple_tree.h>
 
 #define __param(type, name, init, msg)		\
 	static type name = init;		\
@@ -19,6 +21,7 @@ __param(int, search_loops, 1000, "Number of iterations searching the tree");
 __param(bool, search_all, false, "Searches will iterate all nodes in the tree");
 
 __param(uint, max_endpoint, ~0, "Largest value for the interval's endpoint");
+__param(ullong, seed, 3141592653589793238ULL, "Random seed");
 
 static struct rb_root_cached root = RB_ROOT_CACHED;
 static struct interval_tree_node *nodes = NULL;
@@ -59,26 +62,13 @@ static void init(void)
 		queries[i] = (prandom_u32_state(&rnd) >> 4) % max_endpoint;
 }
 
-static int interval_tree_test_init(void)
+static int basic_check(void)
 {
 	int i, j;
-	unsigned long results;
 	cycles_t time1, time2, time;
 
-	nodes = kmalloc_array(nnodes, sizeof(struct interval_tree_node),
-			      GFP_KERNEL);
-	if (!nodes)
-		return -ENOMEM;
-
-	queries = kmalloc_array(nsearches, sizeof(int), GFP_KERNEL);
-	if (!queries) {
-		kfree(nodes);
-		return -ENOMEM;
-	}
-
 	printk(KERN_ALERT "interval tree insert/remove");
 
-	prandom_seed_state(&rnd, 3141592653589793238ULL);
 	init();
 
 	time1 = get_cycles();
@@ -96,8 +86,19 @@ static int interval_tree_test_init(void)
 	time = div_u64(time, perf_loops);
 	printk(" -> %llu cycles\n", (unsigned long long)time);
 
+	return 0;
+}
+
+static int search_check(void)
+{
+	int i, j;
+	unsigned long results;
+	cycles_t time1, time2, time;
+
 	printk(KERN_ALERT "interval tree search");
 
+	init();
+
 	for (j = 0; j < nnodes; j++)
 		interval_tree_insert(nodes + j, &root);
 
@@ -120,6 +121,214 @@ static int interval_tree_test_init(void)
 	printk(" -> %llu cycles (%lu results)\n",
 	       (unsigned long long)time, results);
 
+	for (j = 0; j < nnodes; j++)
+		interval_tree_remove(nodes + j, &root);
+
+	return 0;
+}
+
+static int intersection_range_check(void)
+{
+	int i, j, k;
+	unsigned long start, last;
+	struct interval_tree_node *node;
+	unsigned long *intxn1;
+	unsigned long *intxn2;
+
+	printk(KERN_ALERT "interval tree iteration\n");
+
+	intxn1 = bitmap_alloc(nnodes, GFP_KERNEL);
+	if (!intxn1) {
+		WARN_ON_ONCE("Failed to allocate intxn1\n");
+		return -ENOMEM;
+	}
+
+	intxn2 = bitmap_alloc(nnodes, GFP_KERNEL);
+	if (!intxn2) {
+		WARN_ON_ONCE("Failed to allocate intxn2\n");
+		bitmap_free(intxn1);
+		return -ENOMEM;
+	}
+
+	for (i = 0; i < search_loops; i++) {
+		/* Initialize interval tree for each round */
+		init();
+		for (j = 0; j < nnodes; j++)
+			interval_tree_insert(nodes + j, &root);
+
+		/* Let's try nsearches different ranges */
+		for (k = 0; k < nsearches; k++) {
+			/* Try whole range once */
+			if (!k) {
+				start = 0UL;
+				last = ULONG_MAX;
+			} else {
+				last = (prandom_u32_state(&rnd) >> 4) % max_endpoint;
+				start = (prandom_u32_state(&rnd) >> 4) % last;
+			}
+
+			/* Walk nodes to mark intersection nodes */
+			bitmap_zero(intxn1, nnodes);
+			for (j = 0; j < nnodes; j++) {
+				node = nodes + j;
+
+				if (start <= node->last && last >= node->start)
+					bitmap_set(intxn1, j, 1);
+			}
+
+			/* Iterate tree to clear intersection nodes */
+			bitmap_zero(intxn2, nnodes);
+			for (node = interval_tree_iter_first(&root, start, last); node;
+			     node = interval_tree_iter_next(node, start, last))
+				bitmap_set(intxn2, node - nodes, 1);
+
+			WARN_ON_ONCE(!bitmap_equal(intxn1, intxn2, nnodes));
+		}
+
+		for (j = 0; j < nnodes; j++)
+			interval_tree_remove(nodes + j, &root);
+	}
+
+	bitmap_free(intxn1);
+	bitmap_free(intxn2);
+	return 0;
+}
+
+#ifdef CONFIG_INTERVAL_TREE_SPAN_ITER
+/*
+ * Helper function to get span of current position from maple tree point of
+ * view.
+ */
+static void mas_cur_span(struct ma_state *mas, struct interval_tree_span_iter *state)
+{
+	unsigned long cur_start;
+	unsigned long cur_last;
+	int is_hole;
+
+	if (mas->status == ma_overflow)
+		return;
+
+	/* walk to current position */
+	state->is_hole = mas_walk(mas) ? 0 : 1;
+
+	cur_start = mas->index < state->first_index ?
+			state->first_index : mas->index;
+
+	/* whether we have followers */
+	do {
+
+		cur_last = mas->last > state->last_index ?
+				state->last_index : mas->last;
+
+		is_hole = mas_next_range(mas, state->last_index) ? 0 : 1;
+
+	} while (mas->status != ma_overflow && is_hole == state->is_hole);
+
+	if (state->is_hole) {
+		state->start_hole = cur_start;
+		state->last_hole = cur_last;
+	} else {
+		state->start_used = cur_start;
+		state->last_used = cur_last;
+	}
+
+	/* advance position for next round */
+	if (mas->status != ma_overflow)
+		mas_set(mas, cur_last + 1);
+}
+
+static int span_iteration_check(void)
+{
+	int i, j, k;
+	unsigned long start, last;
+	struct interval_tree_span_iter span, mas_span;
+
+	DEFINE_MTREE(tree);
+
+	MA_STATE(mas, &tree, 0, 0);
+
+	printk(KERN_ALERT "interval tree span iteration\n");
+
+	for (i = 0; i < search_loops; i++) {
+		/* Initialize interval tree for each round */
+		init();
+		for (j = 0; j < nnodes; j++)
+			interval_tree_insert(nodes + j, &root);
+
+		/* Put all the range into maple tree */
+		mt_init_flags(&tree, MT_FLAGS_ALLOC_RANGE);
+		mt_set_in_rcu(&tree);
+
+		for (j = 0; j < nnodes; j++)
+			WARN_ON_ONCE(mtree_store_range(&tree, nodes[j].start,
+					nodes[j].last, nodes + j, GFP_KERNEL));
+
+		/* Let's try nsearches different ranges */
+		for (k = 0; k < nsearches; k++) {
+			/* Try whole range once */
+			if (!k) {
+				start = 0UL;
+				last = ULONG_MAX;
+			} else {
+				last = (prandom_u32_state(&rnd) >> 4) % max_endpoint;
+				start = (prandom_u32_state(&rnd) >> 4) % last;
+			}
+
+			mas_span.first_index = start;
+			mas_span.last_index = last;
+			mas_span.is_hole = -1;
+			mas_set(&mas, start);
+
+			interval_tree_for_each_span(&span, &root, start, last) {
+				mas_cur_span(&mas, &mas_span);
+
+				WARN_ON_ONCE(span.is_hole != mas_span.is_hole);
+
+				if (span.is_hole) {
+					WARN_ON_ONCE(span.start_hole != mas_span.start_hole);
+					WARN_ON_ONCE(span.last_hole != mas_span.last_hole);
+				} else {
+					WARN_ON_ONCE(span.start_used != mas_span.start_used);
+					WARN_ON_ONCE(span.last_used != mas_span.last_used);
+				}
+			}
+
+		}
+
+		WARN_ON_ONCE(mas.status != ma_overflow);
+
+		/* Cleanup maple tree for each round */
+		mtree_destroy(&tree);
+		/* Cleanup interval tree for each round */
+		for (j = 0; j < nnodes; j++)
+			interval_tree_remove(nodes + j, &root);
+	}
+	return 0;
+}
+#else
+static inline int span_iteration_check(void) {return 0; }
+#endif
+
+static int interval_tree_test_init(void)
+{
+	nodes = kmalloc_array(nnodes, sizeof(struct interval_tree_node),
+			      GFP_KERNEL);
+	if (!nodes)
+		return -ENOMEM;
+
+	queries = kmalloc_array(nsearches, sizeof(int), GFP_KERNEL);
+	if (!queries) {
+		kfree(nodes);
+		return -ENOMEM;
+	}
+
+	prandom_seed_state(&rnd, seed);
+
+	basic_check();
+	search_check();
+	intersection_range_check();
+	span_iteration_check();
+
 	kfree(queries);
 	kfree(nodes);
 
diff --git a/lib/lzo/Makefile b/lib/lzo/Makefile
index 2f58fafbbddd..fc7b2b7ef4b2 100644
--- a/lib/lzo/Makefile
+++ b/lib/lzo/Makefile
@@ -1,5 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0-only
-lzo_compress-objs := lzo1x_compress.o
+lzo_compress-objs := lzo1x_compress.o lzo1x_compress_safe.o
 lzo_decompress-objs := lzo1x_decompress_safe.o
 
 obj-$(CONFIG_LZO_COMPRESS) += lzo_compress.o
diff --git a/lib/lzo/lzo1x_compress.c b/lib/lzo/lzo1x_compress.c
index 47d6d43ea957..7b10ca86a893 100644
--- a/lib/lzo/lzo1x_compress.c
+++ b/lib/lzo/lzo1x_compress.c
@@ -18,11 +18,22 @@
 #include <linux/lzo.h>
 #include "lzodefs.h"
 
-static noinline size_t
-lzo1x_1_do_compress(const unsigned char *in, size_t in_len,
-		    unsigned char *out, size_t *out_len,
-		    size_t ti, void *wrkmem, signed char *state_offset,
-		    const unsigned char bitstream_version)
+#undef LZO_UNSAFE
+
+#ifndef LZO_SAFE
+#define LZO_UNSAFE 1
+#define LZO_SAFE(name) name
+#define HAVE_OP(x) 1
+#endif
+
+#define NEED_OP(x) if (!HAVE_OP(x)) goto output_overrun
+
+static noinline int
+LZO_SAFE(lzo1x_1_do_compress)(const unsigned char *in, size_t in_len,
+			      unsigned char **out, unsigned char *op_end,
+			      size_t *tp, void *wrkmem,
+			      signed char *state_offset,
+			      const unsigned char bitstream_version)
 {
 	const unsigned char *ip;
 	unsigned char *op;
@@ -30,8 +41,9 @@ lzo1x_1_do_compress(const unsigned char *in, size_t in_len,
 	const unsigned char * const ip_end = in + in_len - 20;
 	const unsigned char *ii;
 	lzo_dict_t * const dict = (lzo_dict_t *) wrkmem;
+	size_t ti = *tp;
 
-	op = out;
+	op = *out;
 	ip = in;
 	ii = ip;
 	ip += ti < 4 ? 4 - ti : 0;
@@ -116,25 +128,32 @@ next:
 		if (t != 0) {
 			if (t <= 3) {
 				op[*state_offset] |= t;
+				NEED_OP(4);
 				COPY4(op, ii);
 				op += t;
 			} else if (t <= 16) {
+				NEED_OP(17);
 				*op++ = (t - 3);
 				COPY8(op, ii);
 				COPY8(op + 8, ii + 8);
 				op += t;
 			} else {
 				if (t <= 18) {
+					NEED_OP(1);
 					*op++ = (t - 3);
 				} else {
 					size_t tt = t - 18;
+					NEED_OP(1);
 					*op++ = 0;
 					while (unlikely(tt > 255)) {
 						tt -= 255;
+						NEED_OP(1);
 						*op++ = 0;
 					}
+					NEED_OP(1);
 					*op++ = tt;
 				}
+				NEED_OP(t);
 				do {
 					COPY8(op, ii);
 					COPY8(op + 8, ii + 8);
@@ -151,6 +170,7 @@ next:
 		if (unlikely(run_length)) {
 			ip += run_length;
 			run_length -= MIN_ZERO_RUN_LENGTH;
+			NEED_OP(4);
 			put_unaligned_le32((run_length << 21) | 0xfffc18
 					   | (run_length & 0x7), op);
 			op += 4;
@@ -243,10 +263,12 @@ m_len_done:
 		ip += m_len;
 		if (m_len <= M2_MAX_LEN && m_off <= M2_MAX_OFFSET) {
 			m_off -= 1;
+			NEED_OP(2);
 			*op++ = (((m_len - 1) << 5) | ((m_off & 7) << 2));
 			*op++ = (m_off >> 3);
 		} else if (m_off <= M3_MAX_OFFSET) {
 			m_off -= 1;
+			NEED_OP(1);
 			if (m_len <= M3_MAX_LEN)
 				*op++ = (M3_MARKER | (m_len - 2));
 			else {
@@ -254,14 +276,18 @@ m_len_done:
 				*op++ = M3_MARKER | 0;
 				while (unlikely(m_len > 255)) {
 					m_len -= 255;
+					NEED_OP(1);
 					*op++ = 0;
 				}
+				NEED_OP(1);
 				*op++ = (m_len);
 			}
+			NEED_OP(2);
 			*op++ = (m_off << 2);
 			*op++ = (m_off >> 6);
 		} else {
 			m_off -= 0x4000;
+			NEED_OP(1);
 			if (m_len <= M4_MAX_LEN)
 				*op++ = (M4_MARKER | ((m_off >> 11) & 8)
 						| (m_len - 2));
@@ -282,11 +308,14 @@ m_len_done:
 				m_len -= M4_MAX_LEN;
 				*op++ = (M4_MARKER | ((m_off >> 11) & 8));
 				while (unlikely(m_len > 255)) {
+					NEED_OP(1);
 					m_len -= 255;
 					*op++ = 0;
 				}
+				NEED_OP(1);
 				*op++ = (m_len);
 			}
+			NEED_OP(2);
 			*op++ = (m_off << 2);
 			*op++ = (m_off >> 6);
 		}
@@ -295,14 +324,20 @@ finished_writing_instruction:
 		ii = ip;
 		goto next;
 	}
-	*out_len = op - out;
-	return in_end - (ii - ti);
+	*out = op;
+	*tp = in_end - (ii - ti);
+	return LZO_E_OK;
+
+output_overrun:
+	return LZO_E_OUTPUT_OVERRUN;
 }
 
-static int lzogeneric1x_1_compress(const unsigned char *in, size_t in_len,
-		     unsigned char *out, size_t *out_len,
-		     void *wrkmem, const unsigned char bitstream_version)
+static int LZO_SAFE(lzogeneric1x_1_compress)(
+	const unsigned char *in, size_t in_len,
+	unsigned char *out, size_t *out_len,
+	void *wrkmem, const unsigned char bitstream_version)
 {
+	unsigned char * const op_end = out + *out_len;
 	const unsigned char *ip = in;
 	unsigned char *op = out;
 	unsigned char *data_start;
@@ -326,14 +361,18 @@ static int lzogeneric1x_1_compress(const unsigned char *in, size_t in_len,
 	while (l > 20) {
 		size_t ll = min_t(size_t, l, m4_max_offset + 1);
 		uintptr_t ll_end = (uintptr_t) ip + ll;
+		int err;
+
 		if ((ll_end + ((t + ll) >> 5)) <= ll_end)
 			break;
 		BUILD_BUG_ON(D_SIZE * sizeof(lzo_dict_t) > LZO1X_1_MEM_COMPRESS);
 		memset(wrkmem, 0, D_SIZE * sizeof(lzo_dict_t));
-		t = lzo1x_1_do_compress(ip, ll, op, out_len, t, wrkmem,
-					&state_offset, bitstream_version);
+		err = LZO_SAFE(lzo1x_1_do_compress)(
+			ip, ll, &op, op_end, &t, wrkmem,
+			&state_offset, bitstream_version);
+		if (err != LZO_E_OK)
+			return err;
 		ip += ll;
-		op += *out_len;
 		l  -= ll;
 	}
 	t += l;
@@ -342,20 +381,26 @@ static int lzogeneric1x_1_compress(const unsigned char *in, size_t in_len,
 		const unsigned char *ii = in + in_len - t;
 
 		if (op == data_start && t <= 238) {
+			NEED_OP(1);
 			*op++ = (17 + t);
 		} else if (t <= 3) {
 			op[state_offset] |= t;
 		} else if (t <= 18) {
+			NEED_OP(1);
 			*op++ = (t - 3);
 		} else {
 			size_t tt = t - 18;
+			NEED_OP(1);
 			*op++ = 0;
 			while (tt > 255) {
 				tt -= 255;
+				NEED_OP(1);
 				*op++ = 0;
 			}
+			NEED_OP(1);
 			*op++ = tt;
 		}
+		NEED_OP(t);
 		if (t >= 16) do {
 			COPY8(op, ii);
 			COPY8(op + 8, ii + 8);
@@ -368,31 +413,38 @@ static int lzogeneric1x_1_compress(const unsigned char *in, size_t in_len,
 		} while (--t > 0);
 	}
 
+	NEED_OP(3);
 	*op++ = M4_MARKER | 1;
 	*op++ = 0;
 	*op++ = 0;
 
 	*out_len = op - out;
 	return LZO_E_OK;
+
+output_overrun:
+	return LZO_E_OUTPUT_OVERRUN;
 }
 
-int lzo1x_1_compress(const unsigned char *in, size_t in_len,
-		     unsigned char *out, size_t *out_len,
-		     void *wrkmem)
+int LZO_SAFE(lzo1x_1_compress)(const unsigned char *in, size_t in_len,
+			       unsigned char *out, size_t *out_len,
+			       void *wrkmem)
 {
-	return lzogeneric1x_1_compress(in, in_len, out, out_len, wrkmem, 0);
+	return LZO_SAFE(lzogeneric1x_1_compress)(
+		in, in_len, out, out_len, wrkmem, 0);
 }
 
-int lzorle1x_1_compress(const unsigned char *in, size_t in_len,
-		     unsigned char *out, size_t *out_len,
-		     void *wrkmem)
+int LZO_SAFE(lzorle1x_1_compress)(const unsigned char *in, size_t in_len,
+				  unsigned char *out, size_t *out_len,
+				  void *wrkmem)
 {
-	return lzogeneric1x_1_compress(in, in_len, out, out_len,
-				       wrkmem, LZO_VERSION);
+	return LZO_SAFE(lzogeneric1x_1_compress)(
+		in, in_len, out, out_len, wrkmem, LZO_VERSION);
 }
 
-EXPORT_SYMBOL_GPL(lzo1x_1_compress);
-EXPORT_SYMBOL_GPL(lzorle1x_1_compress);
+EXPORT_SYMBOL_GPL(LZO_SAFE(lzo1x_1_compress));
+EXPORT_SYMBOL_GPL(LZO_SAFE(lzorle1x_1_compress));
 
+#ifndef LZO_UNSAFE
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("LZO1X-1 Compressor");
+#endif
diff --git a/lib/lzo/lzo1x_compress_safe.c b/lib/lzo/lzo1x_compress_safe.c
new file mode 100644
index 000000000000..371c9f849492
--- /dev/null
+++ b/lib/lzo/lzo1x_compress_safe.c
@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *  LZO1X Compressor from LZO
+ *
+ *  Copyright (C) 1996-2012 Markus F.X.J. Oberhumer <markus@oberhumer.com>
+ *
+ *  The full LZO package can be found at:
+ *  http://www.oberhumer.com/opensource/lzo/
+ *
+ *  Changed for Linux kernel use by:
+ *  Nitin Gupta <nitingupta910@gmail.com>
+ *  Richard Purdie <rpurdie@openedhand.com>
+ */
+
+#define LZO_SAFE(name) name##_safe
+#define HAVE_OP(x) ((size_t)(op_end - op) >= (size_t)(x))
+
+#include "lzo1x_compress.c"
diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index f7153ade1be5..d0bea23fa4bc 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -584,13 +584,10 @@ static __always_inline bool ma_dead_node(const struct maple_node *node)
  */
 static __always_inline bool mte_dead_node(const struct maple_enode *enode)
 {
-	struct maple_node *parent, *node;
+	struct maple_node *node;
 
 	node = mte_to_node(enode);
-	/* Do not reorder reads from the node prior to the parent check */
-	smp_rmb();
-	parent = mte_parent(enode);
-	return (parent == node);
+	return ma_dead_node(node);
 }
 
 /*
@@ -1245,7 +1242,6 @@ static inline void mas_alloc_nodes(struct ma_state *mas, gfp_t gfp)
 	if (mas->mas_flags & MA_STATE_PREALLOC) {
 		if (allocated)
 			return;
-		BUG_ON(!allocated);
 		WARN_ON(!allocated);
 	}
 
@@ -1353,7 +1349,7 @@ static void mas_node_count(struct ma_state *mas, int count)
  * mas_start() - Sets up maple state for operations.
  * @mas: The maple state.
  *
- * If mas->status == mas_start, then set the min, max and depth to
+ * If mas->status == ma_start, then set the min, max and depth to
  * defaults.
  *
  * Return:
diff --git a/lib/min_heap.c b/lib/min_heap.c
index 4485372ff3b1..96f01a4c5fb6 100644
--- a/lib/min_heap.c
+++ b/lib/min_heap.c
@@ -2,7 +2,7 @@
 #include <linux/export.h>
 #include <linux/min_heap.h>
 
-void __min_heap_init(min_heap_char *heap, void *data, int size)
+void __min_heap_init(min_heap_char *heap, void *data, size_t size)
 {
 	__min_heap_init_inline(heap, data, size);
 }
@@ -20,7 +20,7 @@ bool __min_heap_full(min_heap_char *heap)
 }
 EXPORT_SYMBOL(__min_heap_full);
 
-void __min_heap_sift_down(min_heap_char *heap, int pos, size_t elem_size,
+void __min_heap_sift_down(min_heap_char *heap, size_t pos, size_t elem_size,
 			  const struct min_heap_callbacks *func, void *args)
 {
 	__min_heap_sift_down_inline(heap, pos, elem_size, func, args);
diff --git a/lib/plist.c b/lib/plist.c
index c6bce1226874..330febb4bd7d 100644
--- a/lib/plist.c
+++ b/lib/plist.c
@@ -171,12 +171,24 @@ void plist_requeue(struct plist_node *node, struct plist_head *head)
 
 	plist_del(node, head);
 
+	/*
+	 * After plist_del(), iter is the replacement of the node.  If the node
+	 * was on prio_list, take shortcut to find node_next instead of looping.
+	 */
+	if (!list_empty(&iter->prio_list)) {
+		iter = list_entry(iter->prio_list.next, struct plist_node,
+				  prio_list);
+		node_next = &iter->node_list;
+		goto queue;
+	}
+
 	plist_for_each_continue(iter, head) {
 		if (node->prio != iter->prio) {
 			node_next = &iter->node_list;
 			break;
 		}
 	}
+queue:
 	list_add_tail(&node->node_list, node_next);
 
 	plist_check_head(head);
diff --git a/lib/raid6/s390vx.uc b/lib/raid6/s390vx.uc
index 863e2d320938..8aa53eb2f395 100644
--- a/lib/raid6/s390vx.uc
+++ b/lib/raid6/s390vx.uc
@@ -11,6 +11,7 @@
  * This file is postprocessed using unroll.awk.
  */
 
+#include <linux/cpufeature.h>
 #include <linux/raid/pq.h>
 #include <asm/fpu.h>
 
diff --git a/lib/rbtree_test.c b/lib/rbtree_test.c
index 8655a76d29a1..690cede46ac2 100644
--- a/lib/rbtree_test.c
+++ b/lib/rbtree_test.c
@@ -14,6 +14,7 @@
 __param(int, nnodes, 100, "Number of nodes in the rb-tree");
 __param(int, perf_loops, 1000, "Number of iterations modifying the rb-tree");
 __param(int, check_loops, 100, "Number of iterations modifying and verifying the rb-tree");
+__param(ullong, seed, 3141592653589793238ULL, "Random seed");
 
 struct test_node {
 	u32 key;
@@ -239,19 +240,14 @@ static void check_augmented(int nr_nodes)
 	}
 }
 
-static int __init rbtree_test_init(void)
+static int basic_check(void)
 {
 	int i, j;
 	cycles_t time1, time2, time;
 	struct rb_node *node;
 
-	nodes = kmalloc_array(nnodes, sizeof(*nodes), GFP_KERNEL);
-	if (!nodes)
-		return -ENOMEM;
-
 	printk(KERN_ALERT "rbtree testing");
 
-	prandom_seed_state(&rnd, 3141592653589793238ULL);
 	init();
 
 	time1 = get_cycles();
@@ -343,6 +339,14 @@ static int __init rbtree_test_init(void)
 		check(0);
 	}
 
+	return 0;
+}
+
+static int augmented_check(void)
+{
+	int i, j;
+	cycles_t time1, time2, time;
+
 	printk(KERN_ALERT "augmented rbtree testing");
 
 	init();
@@ -390,6 +394,20 @@ static int __init rbtree_test_init(void)
 		check_augmented(0);
 	}
 
+	return 0;
+}
+
+static int __init rbtree_test_init(void)
+{
+	nodes = kmalloc_array(nnodes, sizeof(*nodes), GFP_KERNEL);
+	if (!nodes)
+		return -ENOMEM;
+
+	prandom_seed_state(&rnd, seed);
+
+	basic_check();
+	augmented_check();
+
 	kfree(nodes);
 
 	return -EAGAIN; /* Fail will directly unload the module */
diff --git a/lib/scatterlist.c b/lib/scatterlist.c
index 5bb6b8aff232..b58d5ef1a34b 100644
--- a/lib/scatterlist.c
+++ b/lib/scatterlist.c
@@ -879,7 +879,7 @@ EXPORT_SYMBOL(sg_miter_skip);
  *   @miter->addr and @miter->length point to the current mapping.
  *
  * Context:
- *   May sleep if !SG_MITER_ATOMIC.
+ *   May sleep if !SG_MITER_ATOMIC && !SG_MITER_LOCAL.
  *
  * Returns:
  *   true if @miter contains the next mapping.  false if end of sg
@@ -901,6 +901,8 @@ bool sg_miter_next(struct sg_mapping_iter *miter)
 
 	if (miter->__flags & SG_MITER_ATOMIC)
 		miter->addr = kmap_atomic(miter->page) + miter->__offset;
+	else if (miter->__flags & SG_MITER_LOCAL)
+		miter->addr = kmap_local_page(miter->page) + miter->__offset;
 	else
 		miter->addr = kmap(miter->page) + miter->__offset;
 
@@ -936,7 +938,9 @@ void sg_miter_stop(struct sg_mapping_iter *miter)
 		if (miter->__flags & SG_MITER_ATOMIC) {
 			WARN_ON_ONCE(!pagefault_disabled());
 			kunmap_atomic(miter->addr);
-		} else
+		} else if (miter->__flags & SG_MITER_LOCAL)
+			kunmap_local(miter->addr);
+		else
 			kunmap(miter->page);
 
 		miter->page = NULL;
@@ -965,7 +969,7 @@ size_t sg_copy_buffer(struct scatterlist *sgl, unsigned int nents, void *buf,
 {
 	unsigned int offset = 0;
 	struct sg_mapping_iter miter;
-	unsigned int sg_flags = SG_MITER_ATOMIC;
+	unsigned int sg_flags = SG_MITER_LOCAL;
 
 	if (to_buffer)
 		sg_flags |= SG_MITER_FROM_SG;
@@ -1080,7 +1084,7 @@ size_t sg_zero_buffer(struct scatterlist *sgl, unsigned int nents,
 {
 	unsigned int offset = 0;
 	struct sg_mapping_iter miter;
-	unsigned int sg_flags = SG_MITER_ATOMIC | SG_MITER_TO_SG;
+	unsigned int sg_flags = SG_MITER_LOCAL | SG_MITER_TO_SG;
 
 	sg_miter_start(&miter, sgl, nents, sg_flags);
 
diff --git a/lib/stackdepot.c b/lib/stackdepot.c
index 245d5b416699..73d7b50924ef 100644
--- a/lib/stackdepot.c
+++ b/lib/stackdepot.c
@@ -591,7 +591,8 @@ depot_stack_handle_t stack_depot_save_flags(unsigned long *entries,
 	depot_stack_handle_t handle = 0;
 	struct page *page = NULL;
 	void *prealloc = NULL;
-	bool can_alloc = depot_flags & STACK_DEPOT_FLAG_CAN_ALLOC;
+	bool allow_spin = gfpflags_allow_spinning(alloc_flags);
+	bool can_alloc = (depot_flags & STACK_DEPOT_FLAG_CAN_ALLOC) && allow_spin;
 	unsigned long flags;
 	u32 hash;
 
@@ -630,7 +631,7 @@ depot_stack_handle_t stack_depot_save_flags(unsigned long *entries,
 			prealloc = page_address(page);
 	}
 
-	if (in_nmi()) {
+	if (in_nmi() || !allow_spin) {
 		/* We can never allocate in NMI context. */
 		WARN_ON_ONCE(can_alloc);
 		/* Best effort; bail if we fail to take the lock. */
@@ -671,7 +672,10 @@ depot_stack_handle_t stack_depot_save_flags(unsigned long *entries,
 exit:
 	if (prealloc) {
 		/* Stack depot didn't use this memory, free it. */
-		free_pages((unsigned long)prealloc, DEPOT_POOL_ORDER);
+		if (!allow_spin)
+			free_pages_nolock(virt_to_page(prealloc), DEPOT_POOL_ORDER);
+		else
+			free_pages((unsigned long)prealloc, DEPOT_POOL_ORDER);
 	}
 	if (found)
 		handle = found->handle.handle;
diff --git a/lib/test_hmm.c b/lib/test_hmm.c
index 056f2e411d7b..5b144bc5c4ec 100644
--- a/lib/test_hmm.c
+++ b/lib/test_hmm.c
@@ -195,7 +195,8 @@ static int dmirror_fops_release(struct inode *inode, struct file *filp)
 
 static struct dmirror_chunk *dmirror_page_to_chunk(struct page *page)
 {
-	return container_of(page->pgmap, struct dmirror_chunk, pagemap);
+	return container_of(page_pgmap(page), struct dmirror_chunk,
+			    pagemap);
 }
 
 static struct dmirror_device *dmirror_page_to_device(struct page *page)
@@ -706,34 +707,23 @@ static int dmirror_check_atomic(struct dmirror *dmirror, unsigned long start,
 	return 0;
 }
 
-static int dmirror_atomic_map(unsigned long start, unsigned long end,
-			      struct page **pages, struct dmirror *dmirror)
+static int dmirror_atomic_map(unsigned long addr, struct page *page,
+		struct dmirror *dmirror)
 {
-	unsigned long pfn, mapped = 0;
-	int i;
+	void *entry;
 
 	/* Map the migrated pages into the device's page tables. */
 	mutex_lock(&dmirror->mutex);
 
-	for (i = 0, pfn = start >> PAGE_SHIFT; pfn < (end >> PAGE_SHIFT); pfn++, i++) {
-		void *entry;
-
-		if (!pages[i])
-			continue;
-
-		entry = pages[i];
-		entry = xa_tag_pointer(entry, DPT_XA_TAG_ATOMIC);
-		entry = xa_store(&dmirror->pt, pfn, entry, GFP_ATOMIC);
-		if (xa_is_err(entry)) {
-			mutex_unlock(&dmirror->mutex);
-			return xa_err(entry);
-		}
-
-		mapped++;
+	entry = xa_tag_pointer(page, DPT_XA_TAG_ATOMIC);
+	entry = xa_store(&dmirror->pt, addr >> PAGE_SHIFT, entry, GFP_ATOMIC);
+	if (xa_is_err(entry)) {
+		mutex_unlock(&dmirror->mutex);
+		return xa_err(entry);
 	}
 
 	mutex_unlock(&dmirror->mutex);
-	return mapped;
+	return 0;
 }
 
 static int dmirror_migrate_finalize_and_map(struct migrate_vma *args,
@@ -780,10 +770,8 @@ static int dmirror_exclusive(struct dmirror *dmirror,
 	unsigned long start, end, addr;
 	unsigned long size = cmd->npages << PAGE_SHIFT;
 	struct mm_struct *mm = dmirror->notifier.mm;
-	struct page *pages[64];
 	struct dmirror_bounce bounce;
-	unsigned long next;
-	int ret;
+	int ret = 0;
 
 	start = cmd->addr;
 	end = start + size;
@@ -795,36 +783,26 @@ static int dmirror_exclusive(struct dmirror *dmirror,
 		return -EINVAL;
 
 	mmap_read_lock(mm);
-	for (addr = start; addr < end; addr = next) {
-		unsigned long mapped = 0;
-		int i;
-
-		next = min(end, addr + (ARRAY_SIZE(pages) << PAGE_SHIFT));
+	for (addr = start; !ret && addr < end; addr += PAGE_SIZE) {
+		struct folio *folio;
+		struct page *page;
 
-		ret = make_device_exclusive_range(mm, addr, next, pages, NULL);
-		/*
-		 * Do dmirror_atomic_map() iff all pages are marked for
-		 * exclusive access to avoid accessing uninitialized
-		 * fields of pages.
-		 */
-		if (ret == (next - addr) >> PAGE_SHIFT)
-			mapped = dmirror_atomic_map(addr, next, pages, dmirror);
-		for (i = 0; i < ret; i++) {
-			if (pages[i]) {
-				unlock_page(pages[i]);
-				put_page(pages[i]);
-			}
+		page = make_device_exclusive(mm, addr, NULL, &folio);
+		if (IS_ERR(page)) {
+			ret = PTR_ERR(page);
+			break;
 		}
 
-		if (addr + (mapped << PAGE_SHIFT) < next) {
-			mmap_read_unlock(mm);
-			mmput(mm);
-			return -EBUSY;
-		}
+		ret = dmirror_atomic_map(addr, page, dmirror);
+		folio_unlock(folio);
+		folio_put(folio);
 	}
 	mmap_read_unlock(mm);
 	mmput(mm);
 
+	if (ret)
+		return ret;
+
 	/* Return the migrated data for verification. */
 	ret = dmirror_bounce_init(&bounce, start, size);
 	if (ret)
diff --git a/lib/test_ida.c b/lib/test_ida.c
index c80155a1956d..63078f8dc13f 100644
--- a/lib/test_ida.c
+++ b/lib/test_ida.c
@@ -189,6 +189,75 @@ static void ida_check_bad_free(struct ida *ida)
 	IDA_BUG_ON(ida, !ida_is_empty(ida));
 }
 
+/*
+ * Check ida_find_first_range() and varriants.
+ */
+static void ida_check_find_first(struct ida *ida)
+{
+	/* IDA is empty; all of the below should be not exist */
+	IDA_BUG_ON(ida, ida_exists(ida, 0));
+	IDA_BUG_ON(ida, ida_exists(ida, 3));
+	IDA_BUG_ON(ida, ida_exists(ida, 63));
+	IDA_BUG_ON(ida, ida_exists(ida, 1023));
+	IDA_BUG_ON(ida, ida_exists(ida, (1 << 20) - 1));
+
+	/* IDA contains a single value entry */
+	IDA_BUG_ON(ida, ida_alloc_min(ida, 3, GFP_KERNEL) != 3);
+	IDA_BUG_ON(ida, ida_exists(ida, 0));
+	IDA_BUG_ON(ida, !ida_exists(ida, 3));
+	IDA_BUG_ON(ida, ida_exists(ida, 63));
+	IDA_BUG_ON(ida, ida_exists(ida, 1023));
+	IDA_BUG_ON(ida, ida_exists(ida, (1 << 20) - 1));
+
+	IDA_BUG_ON(ida, ida_alloc_min(ida, 63, GFP_KERNEL) != 63);
+	IDA_BUG_ON(ida, ida_exists(ida, 0));
+	IDA_BUG_ON(ida, !ida_exists(ida, 3));
+	IDA_BUG_ON(ida, !ida_exists(ida, 63));
+	IDA_BUG_ON(ida, ida_exists(ida, 1023));
+	IDA_BUG_ON(ida, ida_exists(ida, (1 << 20) - 1));
+
+	/* IDA contains a single bitmap */
+	IDA_BUG_ON(ida, ida_alloc_min(ida, 1023, GFP_KERNEL) != 1023);
+	IDA_BUG_ON(ida, ida_exists(ida, 0));
+	IDA_BUG_ON(ida, !ida_exists(ida, 3));
+	IDA_BUG_ON(ida, !ida_exists(ida, 63));
+	IDA_BUG_ON(ida, !ida_exists(ida, 1023));
+	IDA_BUG_ON(ida, ida_exists(ida, (1 << 20) - 1));
+
+	/* IDA contains a tree */
+	IDA_BUG_ON(ida, ida_alloc_min(ida, (1 << 20) - 1, GFP_KERNEL) != (1 << 20) - 1);
+	IDA_BUG_ON(ida, ida_exists(ida, 0));
+	IDA_BUG_ON(ida, !ida_exists(ida, 3));
+	IDA_BUG_ON(ida, !ida_exists(ida, 63));
+	IDA_BUG_ON(ida, !ida_exists(ida, 1023));
+	IDA_BUG_ON(ida, !ida_exists(ida, (1 << 20) - 1));
+
+	/* Now try to find first */
+	IDA_BUG_ON(ida, ida_find_first(ida) != 3);
+	IDA_BUG_ON(ida, ida_find_first_range(ida, -1, 2) != -EINVAL);
+	IDA_BUG_ON(ida, ida_find_first_range(ida, 0, 2) != -ENOENT); // no used ID
+	IDA_BUG_ON(ida, ida_find_first_range(ida, 0, 3) != 3);
+	IDA_BUG_ON(ida, ida_find_first_range(ida, 1, 3) != 3);
+	IDA_BUG_ON(ida, ida_find_first_range(ida, 3, 3) != 3);
+	IDA_BUG_ON(ida, ida_find_first_range(ida, 2, 4) != 3);
+	IDA_BUG_ON(ida, ida_find_first_range(ida, 4, 3) != -ENOENT); // min > max, fail
+	IDA_BUG_ON(ida, ida_find_first_range(ida, 4, 60) != -ENOENT); // no used ID
+	IDA_BUG_ON(ida, ida_find_first_range(ida, 4, 64) != 63);
+	IDA_BUG_ON(ida, ida_find_first_range(ida, 63, 63) != 63);
+	IDA_BUG_ON(ida, ida_find_first_range(ida, 64, 1026) != 1023);
+	IDA_BUG_ON(ida, ida_find_first_range(ida, 1023, 1023) != 1023);
+	IDA_BUG_ON(ida, ida_find_first_range(ida, 1023, (1 << 20) - 1) != 1023);
+	IDA_BUG_ON(ida, ida_find_first_range(ida, 1024, (1 << 20) - 1) != (1 << 20) - 1);
+	IDA_BUG_ON(ida, ida_find_first_range(ida, (1 << 20), INT_MAX) != -ENOENT);
+
+	ida_free(ida, 3);
+	ida_free(ida, 63);
+	ida_free(ida, 1023);
+	ida_free(ida, (1 << 20) - 1);
+
+	IDA_BUG_ON(ida, !ida_is_empty(ida));
+}
+
 static DEFINE_IDA(ida);
 
 static int ida_checks(void)
@@ -202,6 +271,7 @@ static int ida_checks(void)
 	ida_check_max(&ida);
 	ida_check_conv(&ida);
 	ida_check_bad_free(&ida);
+	ida_check_find_first(&ida);
 
 	printk("IDA: %u of %u tests passed\n", tests_passed, tests_run);
 	return (tests_run != tests_passed) ? 0 : -EINVAL;
diff --git a/lib/test_xarray.c b/lib/test_xarray.c
index 0e865bab4a10..080a39d22e73 100644
--- a/lib/test_xarray.c
+++ b/lib/test_xarray.c
@@ -1858,6 +1858,54 @@ static void check_split_1(struct xarray *xa, unsigned long index,
 	xa_destroy(xa);
 }
 
+static void check_split_2(struct xarray *xa, unsigned long index,
+				unsigned int order, unsigned int new_order)
+{
+	XA_STATE_ORDER(xas, xa, index, new_order);
+	unsigned int i, found;
+	void *entry;
+
+	xa_store_order(xa, index, order, xa, GFP_KERNEL);
+	xa_set_mark(xa, index, XA_MARK_1);
+
+	/* allocate a node for xas_try_split() */
+	xas_set_err(&xas, -ENOMEM);
+	XA_BUG_ON(xa, !xas_nomem(&xas, GFP_KERNEL));
+
+	xas_lock(&xas);
+	xas_try_split(&xas, xa, order);
+	if (((new_order / XA_CHUNK_SHIFT) < (order / XA_CHUNK_SHIFT)) &&
+	    new_order < order - 1) {
+		XA_BUG_ON(xa, !xas_error(&xas) || xas_error(&xas) != -EINVAL);
+		xas_unlock(&xas);
+		goto out;
+	}
+	for (i = 0; i < (1 << order); i += (1 << new_order))
+		__xa_store(xa, index + i, xa_mk_index(index + i), 0);
+	xas_unlock(&xas);
+
+	for (i = 0; i < (1 << order); i++) {
+		unsigned int val = index + (i & ~((1 << new_order) - 1));
+		XA_BUG_ON(xa, xa_load(xa, index + i) != xa_mk_index(val));
+	}
+
+	xa_set_mark(xa, index, XA_MARK_0);
+	XA_BUG_ON(xa, !xa_get_mark(xa, index, XA_MARK_0));
+
+	xas_set_order(&xas, index, 0);
+	found = 0;
+	rcu_read_lock();
+	xas_for_each_marked(&xas, entry, ULONG_MAX, XA_MARK_1) {
+		found++;
+		XA_BUG_ON(xa, xa_is_internal(entry));
+	}
+	rcu_read_unlock();
+	XA_BUG_ON(xa, found != 1 << (order - new_order));
+out:
+	xas_destroy(&xas);
+	xa_destroy(xa);
+}
+
 static noinline void check_split(struct xarray *xa)
 {
 	unsigned int order, new_order;
@@ -1869,6 +1917,10 @@ static noinline void check_split(struct xarray *xa)
 			check_split_1(xa, 0, order, new_order);
 			check_split_1(xa, 1UL << order, order, new_order);
 			check_split_1(xa, 3UL << order, order, new_order);
+
+			check_split_2(xa, 0, order, new_order);
+			check_split_2(xa, 1UL << order, order, new_order);
+			check_split_2(xa, 3UL << order, order, new_order);
 		}
 	}
 }
diff --git a/lib/tests/Makefile b/lib/tests/Makefile
index a434c7cb733a..5a4794c1826e 100644
--- a/lib/tests/Makefile
+++ b/lib/tests/Makefile
@@ -27,6 +27,10 @@ obj-$(CONFIG_LIST_KUNIT_TEST) += list-test.o
 obj-$(CONFIG_KFIFO_KUNIT_TEST) += kfifo_kunit.o
 obj-$(CONFIG_TEST_LIST_SORT) += test_list_sort.o
 obj-$(CONFIG_LINEAR_RANGES_TEST) += test_linear_ranges.o
+
+CFLAGS_longest_symbol_kunit.o += $(call cc-disable-warning, missing-prototypes)
+obj-$(CONFIG_LONGEST_SYM_KUNIT_TEST) += longest_symbol_kunit.o
+
 obj-$(CONFIG_MEMCPY_KUNIT_TEST) += memcpy_kunit.o
 CFLAGS_overflow_kunit.o = $(call cc-disable-warning, tautological-constant-out-of-range-compare)
 obj-$(CONFIG_OVERFLOW_KUNIT_TEST) += overflow_kunit.o
diff --git a/lib/tests/longest_symbol_kunit.c b/lib/tests/longest_symbol_kunit.c
new file mode 100644
index 000000000000..e3c28ff1807f
--- /dev/null
+++ b/lib/tests/longest_symbol_kunit.c
@@ -0,0 +1,82 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Test the longest symbol length. Execute with:
+ *  ./tools/testing/kunit/kunit.py run longest-symbol
+ *  --arch=x86_64 --kconfig_add CONFIG_KPROBES=y --kconfig_add CONFIG_MODULES=y
+ *  --kconfig_add CONFIG_RETPOLINE=n --kconfig_add CONFIG_CFI_CLANG=n
+ *  --kconfig_add CONFIG_MITIGATION_RETPOLINE=n
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <kunit/test.h>
+#include <linux/stringify.h>
+#include <linux/kprobes.h>
+#include <linux/kallsyms.h>
+
+#define DI(name) s##name##name
+#define DDI(name) DI(n##name##name)
+#define DDDI(name) DDI(n##name##name)
+#define DDDDI(name) DDDI(n##name##name)
+#define DDDDDI(name) DDDDI(n##name##name)
+
+/*Generate a symbol whose name length is 511 */
+#define LONGEST_SYM_NAME  DDDDDI(g1h2i3j4k5l6m7n)
+
+#define RETURN_LONGEST_SYM 0xAAAAA
+
+noinline int LONGEST_SYM_NAME(void);
+noinline int LONGEST_SYM_NAME(void)
+{
+	return RETURN_LONGEST_SYM;
+}
+
+_Static_assert(sizeof(__stringify(LONGEST_SYM_NAME)) == KSYM_NAME_LEN,
+"Incorrect symbol length found. Expected KSYM_NAME_LEN: "
+__stringify(KSYM_NAME_LEN) ", but found: "
+__stringify(sizeof(LONGEST_SYM_NAME)));
+
+static void test_longest_symbol(struct kunit *test)
+{
+	KUNIT_EXPECT_EQ(test, RETURN_LONGEST_SYM, LONGEST_SYM_NAME());
+};
+
+static void test_longest_symbol_kallsyms(struct kunit *test)
+{
+	unsigned long (*kallsyms_lookup_name)(const char *name);
+	static int (*longest_sym)(void);
+
+	struct kprobe kp = {
+		.symbol_name = "kallsyms_lookup_name",
+	};
+
+	if (register_kprobe(&kp) < 0) {
+		pr_info("%s: kprobe not registered", __func__);
+		KUNIT_FAIL(test, "test_longest_symbol kallsyms: kprobe not registered\n");
+		return;
+	}
+
+	kunit_warn(test, "test_longest_symbol kallsyms: kprobe registered\n");
+	kallsyms_lookup_name = (unsigned long (*)(const char *name))kp.addr;
+	unregister_kprobe(&kp);
+
+	longest_sym =
+		(void *) kallsyms_lookup_name(__stringify(LONGEST_SYM_NAME));
+	KUNIT_EXPECT_EQ(test, RETURN_LONGEST_SYM, longest_sym());
+};
+
+static struct kunit_case longest_symbol_test_cases[] = {
+	KUNIT_CASE(test_longest_symbol),
+	KUNIT_CASE(test_longest_symbol_kallsyms),
+	{}
+};
+
+static struct kunit_suite longest_symbol_test_suite = {
+	.name = "longest-symbol",
+	.test_cases = longest_symbol_test_cases,
+};
+kunit_test_suite(longest_symbol_test_suite);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Test the longest symbol length");
+MODULE_AUTHOR("Sergio González Collado");
diff --git a/lib/tests/module/gen_test_kallsyms.sh b/lib/tests/module/gen_test_kallsyms.sh
index 561dcac0f359..31fe4ed63de8 100755
--- a/lib/tests/module/gen_test_kallsyms.sh
+++ b/lib/tests/module/gen_test_kallsyms.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 TARGET=$(basename $1)
 DIR=lib/tests/module
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 734bd70c8b9b..01699852f30c 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -1699,8 +1699,12 @@ char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
 	return buf;
 }
 
+#pragma GCC diagnostic push
+#ifndef __clang__
+#pragma GCC diagnostic ignored "-Wsuggest-attribute=format"
+#endif
 static char *va_format(char *buf, char *end, struct va_format *va_fmt,
-		       struct printf_spec spec, const char *fmt)
+		       struct printf_spec spec)
 {
 	va_list va;
 
@@ -1713,6 +1717,7 @@ static char *va_format(char *buf, char *end, struct va_format *va_fmt,
 
 	return buf;
 }
+#pragma GCC diagnostic pop
 
 static noinline_for_stack
 char *uuid_string(char *buf, char *end, const u8 *addr,
@@ -2291,9 +2296,6 @@ int __init no_hash_pointers_enable(char *str)
 }
 early_param("no_hash_pointers", no_hash_pointers_enable);
 
-/* Used for Rust formatting ('%pA'). */
-char *rust_fmt_argument(char *buf, char *end, void *ptr);
-
 /*
  * Show a '%p' thing.  A kernel extension is that the '%p' is followed
  * by an extra set of alphanumeric characters that are extended format
@@ -2469,7 +2471,7 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr,
 	case 'U':
 		return uuid_string(buf, end, ptr, spec, fmt);
 	case 'V':
-		return va_format(buf, end, ptr, spec, fmt);
+		return va_format(buf, end, ptr, spec);
 	case 'K':
 		return restricted_pointer(buf, end, ptr, spec);
 	case 'N':
diff --git a/lib/xarray.c b/lib/xarray.c
index 116e9286c64e..9644b18af18d 100644
--- a/lib/xarray.c
+++ b/lib/xarray.c
@@ -278,6 +278,7 @@ void xas_destroy(struct xa_state *xas)
 		xas->xa_alloc = node = next;
 	}
 }
+EXPORT_SYMBOL_GPL(xas_destroy);
 
 /**
  * xas_nomem() - Allocate memory if needed.
@@ -1007,6 +1008,26 @@ static void node_set_marks(struct xa_node *node, unsigned int offset,
 	}
 }
 
+static void __xas_init_node_for_split(struct xa_state *xas,
+		struct xa_node *node, void *entry)
+{
+	unsigned int i;
+	void *sibling = NULL;
+	unsigned int mask = xas->xa_sibs;
+
+	if (!node)
+		return;
+	node->array = xas->xa;
+	for (i = 0; i < XA_CHUNK_SIZE; i++) {
+		if ((i & mask) == 0) {
+			RCU_INIT_POINTER(node->slots[i], entry);
+			sibling = xa_mk_sibling(i);
+		} else {
+			RCU_INIT_POINTER(node->slots[i], sibling);
+		}
+	}
+}
+
 /**
  * xas_split_alloc() - Allocate memory for splitting an entry.
  * @xas: XArray operation state.
@@ -1025,7 +1046,6 @@ void xas_split_alloc(struct xa_state *xas, void *entry, unsigned int order,
 		gfp_t gfp)
 {
 	unsigned int sibs = (1 << (order % XA_CHUNK_SHIFT)) - 1;
-	unsigned int mask = xas->xa_sibs;
 
 	/* XXX: no support for splitting really large entries yet */
 	if (WARN_ON(xas->xa_shift + 2 * XA_CHUNK_SHIFT <= order))
@@ -1034,22 +1054,13 @@ void xas_split_alloc(struct xa_state *xas, void *entry, unsigned int order,
 		return;
 
 	do {
-		unsigned int i;
-		void *sibling = NULL;
 		struct xa_node *node;
 
 		node = kmem_cache_alloc_lru(radix_tree_node_cachep, xas->xa_lru, gfp);
 		if (!node)
 			goto nomem;
-		node->array = xas->xa;
-		for (i = 0; i < XA_CHUNK_SIZE; i++) {
-			if ((i & mask) == 0) {
-				RCU_INIT_POINTER(node->slots[i], entry);
-				sibling = xa_mk_sibling(i);
-			} else {
-				RCU_INIT_POINTER(node->slots[i], sibling);
-			}
-		}
+
+		__xas_init_node_for_split(xas, node, entry);
 		RCU_INIT_POINTER(node->parent, xas->xa_alloc);
 		xas->xa_alloc = node;
 	} while (sibs-- > 0);
@@ -1122,6 +1133,128 @@ void xas_split(struct xa_state *xas, void *entry, unsigned int order)
 	xas_update(xas, node);
 }
 EXPORT_SYMBOL_GPL(xas_split);
+
+/**
+ * xas_try_split_min_order() - Minimal split order xas_try_split() can accept
+ * @order: Current entry order.
+ *
+ * xas_try_split() can split a multi-index entry to smaller than @order - 1 if
+ * no new xa_node is needed. This function provides the minimal order
+ * xas_try_split() supports.
+ *
+ * Return: the minimal order xas_try_split() supports
+ *
+ * Context: Any context.
+ *
+ */
+unsigned int xas_try_split_min_order(unsigned int order)
+{
+	if (order % XA_CHUNK_SHIFT == 0)
+		return order == 0 ? 0 : order - 1;
+
+	return order - (order % XA_CHUNK_SHIFT);
+}
+EXPORT_SYMBOL_GPL(xas_try_split_min_order);
+
+/**
+ * xas_try_split() - Try to split a multi-index entry.
+ * @xas: XArray operation state.
+ * @entry: New entry to store in the array.
+ * @order: Current entry order.
+ *
+ * The size of the new entries is set in @xas.  The value in @entry is
+ * copied to all the replacement entries. If and only if one new xa_node is
+ * needed, the function will use GFP_NOWAIT to get one if xas->xa_alloc is
+ * NULL. If more new xa_node are needed, the function gives EINVAL error.
+ *
+ * NOTE: use xas_try_split_min_order() to get next split order instead of
+ * @order - 1 if you want to minmize xas_try_split() calls.
+ *
+ * Context: Any context.  The caller should hold the xa_lock.
+ */
+void xas_try_split(struct xa_state *xas, void *entry, unsigned int order)
+{
+	unsigned int sibs = (1 << (order % XA_CHUNK_SHIFT)) - 1;
+	unsigned int offset, marks;
+	struct xa_node *node;
+	void *curr = xas_load(xas);
+	int values = 0;
+	gfp_t gfp = GFP_NOWAIT;
+
+	node = xas->xa_node;
+	if (xas_top(node))
+		return;
+
+	if (xas->xa->xa_flags & XA_FLAGS_ACCOUNT)
+		gfp |= __GFP_ACCOUNT;
+
+	marks = node_get_marks(node, xas->xa_offset);
+
+	offset = xas->xa_offset + sibs;
+
+	if (xas->xa_shift < node->shift) {
+		struct xa_node *child = xas->xa_alloc;
+		unsigned int expected_sibs =
+			(1 << ((order - 1) % XA_CHUNK_SHIFT)) - 1;
+
+		/*
+		 * No support for splitting sibling entries
+		 * (horizontally) or cascade split (vertically), which
+		 * requires two or more new xa_nodes.
+		 * Since if one xa_node allocation fails,
+		 * it is hard to free the prior allocations.
+		 */
+		if (sibs || xas->xa_sibs != expected_sibs) {
+			xas_destroy(xas);
+			xas_set_err(xas, -EINVAL);
+			return;
+		}
+
+		if (!child) {
+			child = kmem_cache_alloc_lru(radix_tree_node_cachep,
+						     xas->xa_lru, gfp);
+			if (!child) {
+				xas_destroy(xas);
+				xas_set_err(xas, -ENOMEM);
+				return;
+			}
+			RCU_INIT_POINTER(child->parent, xas->xa_alloc);
+		}
+		__xas_init_node_for_split(xas, child, entry);
+
+		xas->xa_alloc = rcu_dereference_raw(child->parent);
+		child->shift = node->shift - XA_CHUNK_SHIFT;
+		child->offset = offset;
+		child->count = XA_CHUNK_SIZE;
+		child->nr_values = xa_is_value(entry) ?
+				XA_CHUNK_SIZE : 0;
+		RCU_INIT_POINTER(child->parent, node);
+		node_set_marks(node, offset, child, xas->xa_sibs,
+				marks);
+		rcu_assign_pointer(node->slots[offset],
+				xa_mk_node(child));
+		if (xa_is_value(curr))
+			values--;
+		xas_update(xas, child);
+
+	} else {
+		do {
+			unsigned int canon = offset - xas->xa_sibs;
+
+			node_set_marks(node, canon, NULL, 0, marks);
+			rcu_assign_pointer(node->slots[canon], entry);
+			while (offset > canon)
+				rcu_assign_pointer(node->slots[offset--],
+						xa_mk_sibling(canon));
+			values += (xa_is_value(entry) - xa_is_value(curr)) *
+					(xas->xa_sibs + 1);
+		} while (offset-- > xas->xa_offset);
+	}
+
+	node->nr_values += values;
+	xas_update(xas, node);
+}
+EXPORT_SYMBOL_GPL(xas_try_split);
 #endif
 
 /**
diff --git a/lib/zlib_deflate/deflate.c b/lib/zlib_deflate/deflate.c
index 3a1d8d34182e..8fb2a3e17c0e 100644
--- a/lib/zlib_deflate/deflate.c
+++ b/lib/zlib_deflate/deflate.c
@@ -151,9 +151,6 @@ static const config configuration_table[10] = {
  * meaning.
  */
 
-#define EQUAL 0
-/* result of memcmp for equal strings */
-
 /* ===========================================================================
  * Update a hash value with the given input byte
  * IN  assertion: all calls to UPDATE_HASH are made with consecutive
@@ -713,8 +710,7 @@ static void check_match(
 )
 {
     /* check that the match is indeed a match */
-    if (memcmp((char *)s->window + match,
-                (char *)s->window + start, length) != EQUAL) {
+    if (memcmp((char *)s->window + match, (char *)s->window + start, length)) {
         fprintf(stderr, " start %u, match %u, length %d\n",
 		start, match, length);
         do {