Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 1606 insertions, 0 deletions

diff --git a/lib/test_bitmap.c b/lib/test_bitmap.c
new file mode 100644
index 000000000..56bd23059
--- /dev/null
+++ b/lib/test_bitmap.c
@@ -0,0 +1,1606 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Test cases for bitmap API.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/bitmap.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/printk.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/uaccess.h>
+
+#include "../tools/testing/selftests/kselftest_module.h"
+
+#define EXP1_IN_BITS	(sizeof(exp1) * 8)
+
+KSTM_MODULE_GLOBALS();
+
+static char pbl_buffer[PAGE_SIZE] __initdata;
+static char print_buf[PAGE_SIZE * 2] __initdata;
+
+static const unsigned long exp1[] __initconst = {
+	BITMAP_FROM_U64(1),
+	BITMAP_FROM_U64(2),
+	BITMAP_FROM_U64(0x0000ffff),
+	BITMAP_FROM_U64(0xffff0000),
+	BITMAP_FROM_U64(0x55555555),
+	BITMAP_FROM_U64(0xaaaaaaaa),
+	BITMAP_FROM_U64(0x11111111),
+	BITMAP_FROM_U64(0x22222222),
+	BITMAP_FROM_U64(0xffffffff),
+	BITMAP_FROM_U64(0xfffffffe),
+	BITMAP_FROM_U64(0x3333333311111111ULL),
+	BITMAP_FROM_U64(0xffffffff77777777ULL),
+	BITMAP_FROM_U64(0),
+	BITMAP_FROM_U64(0x00008000),
+	BITMAP_FROM_U64(0x80000000),
+};
+
+static const unsigned long exp2[] __initconst = {
+	BITMAP_FROM_U64(0x3333333311111111ULL),
+	BITMAP_FROM_U64(0xffffffff77777777ULL),
+};
+
+/* Fibonacci sequence */
+static const unsigned long exp2_to_exp3_mask[] __initconst = {
+	BITMAP_FROM_U64(0x008000020020212eULL),
+};
+/* exp3_0_1 = (exp2[0] & ~exp2_to_exp3_mask) | (exp2[1] & exp2_to_exp3_mask) */
+static const unsigned long exp3_0_1[] __initconst = {
+	BITMAP_FROM_U64(0x33b3333311313137ULL),
+};
+/* exp3_1_0 = (exp2[1] & ~exp2_to_exp3_mask) | (exp2[0] & exp2_to_exp3_mask) */
+static const unsigned long exp3_1_0[] __initconst = {
+	BITMAP_FROM_U64(0xff7fffff77575751ULL),
+};
+
+static bool __init
+__check_eq_ulong(const char *srcfile, unsigned int line,
+		 const unsigned long exp_ulong, unsigned long x)
+{
+	if (exp_ulong != x) {
+		pr_err("[%s:%u] expected %lu, got %lu\n",
+			srcfile, line, exp_ulong, x);
+		return false;
+	}
+	return true;
+}
+
+static bool __init
+__check_eq_bitmap(const char *srcfile, unsigned int line,
+		  const unsigned long *exp_bmap, const unsigned long *bmap,
+		  unsigned int nbits)
+{
+	if (!bitmap_equal(exp_bmap, bmap, nbits)) {
+		pr_warn("[%s:%u] bitmaps contents differ: expected \"%*pbl\", got \"%*pbl\"\n",
+			srcfile, line,
+			nbits, exp_bmap, nbits, bmap);
+		return false;
+	}
+	return true;
+}
+
+static bool __init
+__check_eq_pbl(const char *srcfile, unsigned int line,
+	       const char *expected_pbl,
+	       const unsigned long *bitmap, unsigned int nbits)
+{
+	snprintf(pbl_buffer, sizeof(pbl_buffer), "%*pbl", nbits, bitmap);
+	if (strcmp(expected_pbl, pbl_buffer)) {
+		pr_warn("[%s:%u] expected \"%s\", got \"%s\"\n",
+			srcfile, line,
+			expected_pbl, pbl_buffer);
+		return false;
+	}
+	return true;
+}
+
+static bool __init __check_eq_clump8(const char *srcfile, unsigned int line,
+				    const unsigned int offset,
+				    const unsigned int size,
+				    const unsigned char *const clump_exp,
+				    const unsigned long *const clump)
+{
+	unsigned long exp;
+
+	if (offset >= size) {
+		pr_warn("[%s:%u] bit offset for clump out-of-bounds: expected less than %u, got %u\n",
+			srcfile, line, size, offset);
+		return false;
+	}
+
+	exp = clump_exp[offset / 8];
+	if (!exp) {
+		pr_warn("[%s:%u] bit offset for zero clump: expected nonzero clump, got bit offset %u with clump value 0",
+			srcfile, line, offset);
+		return false;
+	}
+
+	if (*clump != exp) {
+		pr_warn("[%s:%u] expected clump value of 0x%lX, got clump value of 0x%lX",
+			srcfile, line, exp, *clump);
+		return false;
+	}
+
+	return true;
+}
+
+static bool __init
+__check_eq_str(const char *srcfile, unsigned int line,
+		const char *exp_str, const char *str,
+		unsigned int len)
+{
+	bool eq;
+
+	eq = strncmp(exp_str, str, len) == 0;
+	if (!eq)
+		pr_err("[%s:%u] expected %s, got %s\n", srcfile, line, exp_str, str);
+
+	return eq;
+}
+
+#define __expect_eq(suffix, ...)					\
+	({								\
+		int result = 0;						\
+		total_tests++;						\
+		if (!__check_eq_ ## suffix(__FILE__, __LINE__,		\
+					   ##__VA_ARGS__)) {		\
+			failed_tests++;					\
+			result = 1;					\
+		}							\
+		result;							\
+	})
+
+#define expect_eq_ulong(...)		__expect_eq(ulong, ##__VA_ARGS__)
+#define expect_eq_uint(x, y)		expect_eq_ulong((unsigned int)(x), (unsigned int)(y))
+#define expect_eq_bitmap(...)		__expect_eq(bitmap, ##__VA_ARGS__)
+#define expect_eq_pbl(...)		__expect_eq(pbl, ##__VA_ARGS__)
+#define expect_eq_u32_array(...)	__expect_eq(u32_array, ##__VA_ARGS__)
+#define expect_eq_clump8(...)		__expect_eq(clump8, ##__VA_ARGS__)
+#define expect_eq_str(...)		__expect_eq(str, ##__VA_ARGS__)
+
+static void __init test_zero_clear(void)
+{
+	DECLARE_BITMAP(bmap, 1024);
+
+	/* Known way to set all bits */
+	memset(bmap, 0xff, 128);
+
+	expect_eq_pbl("0-22", bmap, 23);
+	expect_eq_pbl("0-1023", bmap, 1024);
+
+	/* single-word bitmaps */
+	bitmap_clear(bmap, 0, 9);
+	expect_eq_pbl("9-1023", bmap, 1024);
+
+	bitmap_zero(bmap, 35);
+	expect_eq_pbl("64-1023", bmap, 1024);
+
+	/* cross boundaries operations */
+	bitmap_clear(bmap, 79, 19);
+	expect_eq_pbl("64-78,98-1023", bmap, 1024);
+
+	bitmap_zero(bmap, 115);
+	expect_eq_pbl("128-1023", bmap, 1024);
+
+	/* Zeroing entire area */
+	bitmap_zero(bmap, 1024);
+	expect_eq_pbl("", bmap, 1024);
+}
+
+static void __init test_find_nth_bit(void)
+{
+	unsigned long b, bit, cnt = 0;
+	DECLARE_BITMAP(bmap, 64 * 3);
+
+	bitmap_zero(bmap, 64 * 3);
+	__set_bit(10, bmap);
+	__set_bit(20, bmap);
+	__set_bit(30, bmap);
+	__set_bit(40, bmap);
+	__set_bit(50, bmap);
+	__set_bit(60, bmap);
+	__set_bit(80, bmap);
+	__set_bit(123, bmap);
+
+	expect_eq_uint(10,  find_nth_bit(bmap, 64 * 3, 0));
+	expect_eq_uint(20,  find_nth_bit(bmap, 64 * 3, 1));
+	expect_eq_uint(30,  find_nth_bit(bmap, 64 * 3, 2));
+	expect_eq_uint(40,  find_nth_bit(bmap, 64 * 3, 3));
+	expect_eq_uint(50,  find_nth_bit(bmap, 64 * 3, 4));
+	expect_eq_uint(60,  find_nth_bit(bmap, 64 * 3, 5));
+	expect_eq_uint(80,  find_nth_bit(bmap, 64 * 3, 6));
+	expect_eq_uint(123, find_nth_bit(bmap, 64 * 3, 7));
+	expect_eq_uint(0,   !!(find_nth_bit(bmap, 64 * 3, 8) < 64 * 3));
+
+	expect_eq_uint(10,  find_nth_bit(bmap, 64 * 3 - 1, 0));
+	expect_eq_uint(20,  find_nth_bit(bmap, 64 * 3 - 1, 1));
+	expect_eq_uint(30,  find_nth_bit(bmap, 64 * 3 - 1, 2));
+	expect_eq_uint(40,  find_nth_bit(bmap, 64 * 3 - 1, 3));
+	expect_eq_uint(50,  find_nth_bit(bmap, 64 * 3 - 1, 4));
+	expect_eq_uint(60,  find_nth_bit(bmap, 64 * 3 - 1, 5));
+	expect_eq_uint(80,  find_nth_bit(bmap, 64 * 3 - 1, 6));
+	expect_eq_uint(123, find_nth_bit(bmap, 64 * 3 - 1, 7));
+	expect_eq_uint(0,   !!(find_nth_bit(bmap, 64 * 3 - 1, 8) < 64 * 3 - 1));
+
+	for_each_set_bit(bit, exp1, EXP1_IN_BITS) {
+		b = find_nth_bit(exp1, EXP1_IN_BITS, cnt++);
+		expect_eq_uint(b, bit);
+	}
+}
+
+static void __init
+test_bitmap_find_next_zero_area_off(void)
+{
+	DECLARE_BITMAP(bmap, 192);
+
+	bitmap_set(bmap, 0, 192);
+
+	bitmap_clear(bmap, 0, 8);
+	__clear_bit(50, bmap);
+	bitmap_clear(bmap, 60, 18);
+	__set_bit(69, bmap);
+	__clear_bit(80, bmap);
+	bitmap_clear(bmap, 100, 10);
+	__clear_bit(120, bmap);
+	bitmap_clear(bmap, 145, 8);
+	bitmap_clear(bmap, 160, 32);
+
+	expect_eq_uint(0,
+		bitmap_find_next_zero_area_off(bmap, 192, 0, 8, 0, 0));
+	expect_eq_uint(0,
+		bitmap_find_next_zero_area_off(bmap, 192, 0, 8, 3, 0));
+	expect_eq_uint(163,
+		bitmap_find_next_zero_area_off(bmap, 192, 0, 8, 3, 1));
+	expect_eq_uint(60,
+		bitmap_find_next_zero_area_off(bmap, 192, 1, 8, 0, 0));
+	expect_eq_uint(160,
+		bitmap_find_next_zero_area_off(bmap, 192, 1, 8, 7, 0));
+	expect_eq_uint(60,
+		bitmap_find_next_zero_area_off(bmap, 192, 1, 8, 7, 4));
+	expect_eq_uint(100,
+		bitmap_find_next_zero_area_off(bmap, 192, 0, 10, 0, 0));
+	expect_eq_uint(160,
+		bitmap_find_next_zero_area_off(bmap, 192, 0, 32, 0, 0));
+	expect_eq_uint(1,
+		!!(bitmap_find_next_zero_area_off(bmap, 192, 0, 33, 0, 0) >= 192));
+}
+
+static void __init test_fill_set(void)
+{
+	DECLARE_BITMAP(bmap, 1024);
+
+	/* Known way to clear all bits */
+	memset(bmap, 0x00, 128);
+
+	expect_eq_pbl("", bmap, 23);
+	expect_eq_pbl("", bmap, 1024);
+
+	/* single-word bitmaps */
+	bitmap_set(bmap, 0, 9);
+	expect_eq_pbl("0-8", bmap, 1024);
+
+	bitmap_fill(bmap, 35);
+	expect_eq_pbl("0-63", bmap, 1024);
+
+	/* cross boundaries operations */
+	bitmap_set(bmap, 79, 19);
+	expect_eq_pbl("0-63,79-97", bmap, 1024);
+
+	bitmap_fill(bmap, 115);
+	expect_eq_pbl("0-127", bmap, 1024);
+
+	/* Zeroing entire area */
+	bitmap_fill(bmap, 1024);
+	expect_eq_pbl("0-1023", bmap, 1024);
+}
+
+static void __init test_copy(void)
+{
+	DECLARE_BITMAP(bmap1, 1024);
+	DECLARE_BITMAP(bmap2, 1024);
+
+	bitmap_zero(bmap1, 1024);
+	bitmap_zero(bmap2, 1024);
+
+	/* single-word bitmaps */
+	bitmap_set(bmap1, 0, 19);
+	bitmap_copy(bmap2, bmap1, 23);
+	expect_eq_pbl("0-18", bmap2, 1024);
+
+	bitmap_set(bmap2, 0, 23);
+	bitmap_copy(bmap2, bmap1, 23);
+	expect_eq_pbl("0-18", bmap2, 1024);
+
+	/* multi-word bitmaps */
+	bitmap_set(bmap1, 0, 109);
+	bitmap_copy(bmap2, bmap1, 1024);
+	expect_eq_pbl("0-108", bmap2, 1024);
+
+	bitmap_fill(bmap2, 1024);
+	bitmap_copy(bmap2, bmap1, 1024);
+	expect_eq_pbl("0-108", bmap2, 1024);
+
+	/* the following tests assume a 32- or 64-bit arch (even 128b
+	 * if we care)
+	 */
+
+	bitmap_fill(bmap2, 1024);
+	bitmap_copy(bmap2, bmap1, 109);  /* ... but 0-padded til word length */
+	expect_eq_pbl("0-108,128-1023", bmap2, 1024);
+
+	bitmap_fill(bmap2, 1024);
+	bitmap_copy(bmap2, bmap1, 97);  /* ... but aligned on word length */
+	expect_eq_pbl("0-108,128-1023", bmap2, 1024);
+}
+
+static void __init test_bitmap_region(void)
+{
+	int pos, order;
+
+	DECLARE_BITMAP(bmap, 1000);
+
+	bitmap_zero(bmap, 1000);
+
+	for (order = 0; order < 10; order++) {
+		pos = bitmap_find_free_region(bmap, 1000, order);
+		if (order == 0)
+			expect_eq_uint(pos, 0);
+		else
+			expect_eq_uint(pos, order < 9 ? BIT(order) : -ENOMEM);
+	}
+
+	bitmap_release_region(bmap, 0, 0);
+	for (order = 1; order < 9; order++)
+		bitmap_release_region(bmap, BIT(order), order);
+
+	expect_eq_uint(bitmap_weight(bmap, 1000), 0);
+}
+
+#define EXP2_IN_BITS	(sizeof(exp2) * 8)
+
+static void __init test_replace(void)
+{
+	unsigned int nbits = 64;
+	unsigned int nlongs = DIV_ROUND_UP(nbits, BITS_PER_LONG);
+	DECLARE_BITMAP(bmap, 1024);
+
+	BUILD_BUG_ON(EXP2_IN_BITS < nbits * 2);
+
+	bitmap_zero(bmap, 1024);
+	bitmap_replace(bmap, &exp2[0 * nlongs], &exp2[1 * nlongs], exp2_to_exp3_mask, nbits);
+	expect_eq_bitmap(bmap, exp3_0_1, nbits);
+
+	bitmap_zero(bmap, 1024);
+	bitmap_replace(bmap, &exp2[1 * nlongs], &exp2[0 * nlongs], exp2_to_exp3_mask, nbits);
+	expect_eq_bitmap(bmap, exp3_1_0, nbits);
+
+	bitmap_fill(bmap, 1024);
+	bitmap_replace(bmap, &exp2[0 * nlongs], &exp2[1 * nlongs], exp2_to_exp3_mask, nbits);
+	expect_eq_bitmap(bmap, exp3_0_1, nbits);
+
+	bitmap_fill(bmap, 1024);
+	bitmap_replace(bmap, &exp2[1 * nlongs], &exp2[0 * nlongs], exp2_to_exp3_mask, nbits);
+	expect_eq_bitmap(bmap, exp3_1_0, nbits);
+}
+
+static const unsigned long sg_mask[] __initconst = {
+	BITMAP_FROM_U64(0x000000000000035aULL),
+	BITMAP_FROM_U64(0x0000000000000000ULL),
+};
+
+static const unsigned long sg_src[] __initconst = {
+	BITMAP_FROM_U64(0x0000000000000667ULL),
+	BITMAP_FROM_U64(0x0000000000000000ULL),
+};
+
+static const unsigned long sg_gather_exp[] __initconst = {
+	BITMAP_FROM_U64(0x0000000000000029ULL),
+	BITMAP_FROM_U64(0x0000000000000000ULL),
+};
+
+static const unsigned long sg_scatter_exp[] __initconst = {
+	BITMAP_FROM_U64(0x000000000000021aULL),
+	BITMAP_FROM_U64(0x0000000000000000ULL),
+};
+
+static void __init test_bitmap_sg(void)
+{
+	unsigned int nbits = 64;
+	DECLARE_BITMAP(bmap_gather, 100);
+	DECLARE_BITMAP(bmap_scatter, 100);
+	DECLARE_BITMAP(bmap_tmp, 100);
+	DECLARE_BITMAP(bmap_res, 100);
+
+	/* Simple gather call */
+	bitmap_zero(bmap_gather, 100);
+	bitmap_gather(bmap_gather, sg_src, sg_mask, nbits);
+	expect_eq_bitmap(sg_gather_exp, bmap_gather, 100);
+
+	/* Simple scatter call */
+	bitmap_zero(bmap_scatter, 100);
+	bitmap_scatter(bmap_scatter, sg_src, sg_mask, nbits);
+	expect_eq_bitmap(sg_scatter_exp, bmap_scatter, 100);
+
+	/* Scatter/gather relationship */
+	bitmap_zero(bmap_tmp, 100);
+	bitmap_zero(bmap_res, 100);
+	bitmap_gather(bmap_tmp, bmap_scatter, sg_mask, nbits);
+	bitmap_scatter(bmap_res, bmap_tmp, sg_mask, nbits);
+	expect_eq_bitmap(bmap_scatter, bmap_res, 100);
+}
+
+#define PARSE_TIME	0x1
+#define NO_LEN		0x2
+
+struct test_bitmap_parselist{
+	const int errno;
+	const char *in;
+	const unsigned long *expected;
+	const int nbits;
+	const int flags;
+};
+
+static const struct test_bitmap_parselist parselist_tests[] __initconst = {
+#define step (sizeof(u64) / sizeof(unsigned long))
+
+	{0, "0",			&exp1[0], 8, 0},
+	{0, "1",			&exp1[1 * step], 8, 0},
+	{0, "0-15",			&exp1[2 * step], 32, 0},
+	{0, "16-31",			&exp1[3 * step], 32, 0},
+	{0, "0-31:1/2",			&exp1[4 * step], 32, 0},
+	{0, "1-31:1/2",			&exp1[5 * step], 32, 0},
+	{0, "0-31:1/4",			&exp1[6 * step], 32, 0},
+	{0, "1-31:1/4",			&exp1[7 * step], 32, 0},
+	{0, "0-31:4/4",			&exp1[8 * step], 32, 0},
+	{0, "1-31:4/4",			&exp1[9 * step], 32, 0},
+	{0, "0-31:1/4,32-63:2/4",	&exp1[10 * step], 64, 0},
+	{0, "0-31:3/4,32-63:4/4",	&exp1[11 * step], 64, 0},
+	{0, "  ,,  0-31:3/4  ,, 32-63:4/4  ,,  ",	&exp1[11 * step], 64, 0},
+
+	{0, "0-31:1/4,32-63:2/4,64-95:3/4,96-127:4/4",	exp2, 128, 0},
+
+	{0, "0-2047:128/256", NULL, 2048, PARSE_TIME},
+
+	{0, "",				&exp1[12 * step], 8, 0},
+	{0, "\n",			&exp1[12 * step], 8, 0},
+	{0, ",,  ,,  , ,  ,",		&exp1[12 * step], 8, 0},
+	{0, " ,  ,,  , ,   ",		&exp1[12 * step], 8, 0},
+	{0, " ,  ,,  , ,   \n",		&exp1[12 * step], 8, 0},
+
+	{0, "0-0",			&exp1[0], 32, 0},
+	{0, "1-1",			&exp1[1 * step], 32, 0},
+	{0, "15-15",			&exp1[13 * step], 32, 0},
+	{0, "31-31",			&exp1[14 * step], 32, 0},
+
+	{0, "0-0:0/1",			&exp1[12 * step], 32, 0},
+	{0, "0-0:1/1",			&exp1[0], 32, 0},
+	{0, "0-0:1/31",			&exp1[0], 32, 0},
+	{0, "0-0:31/31",		&exp1[0], 32, 0},
+	{0, "1-1:1/1",			&exp1[1 * step], 32, 0},
+	{0, "0-15:16/31",		&exp1[2 * step], 32, 0},
+	{0, "15-15:1/2",		&exp1[13 * step], 32, 0},
+	{0, "15-15:31/31",		&exp1[13 * step], 32, 0},
+	{0, "15-31:1/31",		&exp1[13 * step], 32, 0},
+	{0, "16-31:16/31",		&exp1[3 * step], 32, 0},
+	{0, "31-31:31/31",		&exp1[14 * step], 32, 0},
+
+	{0, "N-N",			&exp1[14 * step], 32, 0},
+	{0, "0-0:1/N",			&exp1[0], 32, 0},
+	{0, "0-0:N/N",			&exp1[0], 32, 0},
+	{0, "0-15:16/N",		&exp1[2 * step], 32, 0},
+	{0, "15-15:N/N",		&exp1[13 * step], 32, 0},
+	{0, "15-N:1/N",			&exp1[13 * step], 32, 0},
+	{0, "16-N:16/N",		&exp1[3 * step], 32, 0},
+	{0, "N-N:N/N",			&exp1[14 * step], 32, 0},
+
+	{0, "0-N:1/3,1-N:1/3,2-N:1/3",		&exp1[8 * step], 32, 0},
+	{0, "0-31:1/3,1-31:1/3,2-31:1/3",	&exp1[8 * step], 32, 0},
+	{0, "1-10:8/12,8-31:24/29,0-31:0/3",	&exp1[9 * step], 32, 0},
+
+	{0,	  "all",		&exp1[8 * step], 32, 0},
+	{0,	  "0, 1, all,  ",	&exp1[8 * step], 32, 0},
+	{0,	  "all:1/2",		&exp1[4 * step], 32, 0},
+	{0,	  "ALL:1/2",		&exp1[4 * step], 32, 0},
+	{-EINVAL, "al", NULL, 8, 0},
+	{-EINVAL, "alll", NULL, 8, 0},
+
+	{-EINVAL, "-1",	NULL, 8, 0},
+	{-EINVAL, "-0",	NULL, 8, 0},
+	{-EINVAL, "10-1", NULL, 8, 0},
+	{-ERANGE, "8-8", NULL, 8, 0},
+	{-ERANGE, "0-31", NULL, 8, 0},
+	{-EINVAL, "0-31:", NULL, 32, 0},
+	{-EINVAL, "0-31:0", NULL, 32, 0},
+	{-EINVAL, "0-31:0/", NULL, 32, 0},
+	{-EINVAL, "0-31:0/0", NULL, 32, 0},
+	{-EINVAL, "0-31:1/0", NULL, 32, 0},
+	{-EINVAL, "0-31:10/1", NULL, 32, 0},
+	{-EOVERFLOW, "0-98765432123456789:10/1", NULL, 8, 0},
+
+	{-EINVAL, "a-31", NULL, 8, 0},
+	{-EINVAL, "0-a1", NULL, 8, 0},
+	{-EINVAL, "a-31:10/1", NULL, 8, 0},
+	{-EINVAL, "0-31:a/1", NULL, 8, 0},
+	{-EINVAL, "0-\n", NULL, 8, 0},
+
+};
+
+static void __init test_bitmap_parselist(void)
+{
+	int i;
+	int err;
+	ktime_t time;
+	DECLARE_BITMAP(bmap, 2048);
+
+	for (i = 0; i < ARRAY_SIZE(parselist_tests); i++) {
+#define ptest parselist_tests[i]
+
+		time = ktime_get();
+		err = bitmap_parselist(ptest.in, bmap, ptest.nbits);
+		time = ktime_get() - time;
+
+		if (err != ptest.errno) {
+			pr_err("parselist: %d: input is %s, errno is %d, expected %d\n",
+					i, ptest.in, err, ptest.errno);
+			failed_tests++;
+			continue;
+		}
+
+		if (!err && ptest.expected
+			 && !__bitmap_equal(bmap, ptest.expected, ptest.nbits)) {
+			pr_err("parselist: %d: input is %s, result is 0x%lx, expected 0x%lx\n",
+					i, ptest.in, bmap[0],
+					*ptest.expected);
+			failed_tests++;
+			continue;
+		}
+
+		if (ptest.flags & PARSE_TIME)
+			pr_info("parselist('%s'):\t%llu\n", ptest.in, time);
+
+#undef ptest
+	}
+}
+
+static void __init test_bitmap_printlist(void)
+{
+	unsigned long *bmap = kmalloc(PAGE_SIZE, GFP_KERNEL);
+	char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+	char expected[256];
+	int ret, slen;
+	ktime_t time;
+
+	if (!buf || !bmap)
+		goto out;
+
+	memset(bmap, -1, PAGE_SIZE);
+	slen = snprintf(expected, 256, "0-%ld", PAGE_SIZE * 8 - 1);
+	if (slen < 0)
+		goto out;
+
+	time = ktime_get();
+	ret = scnprintf(buf, PAGE_SIZE, "%*pbl", (int)PAGE_SIZE * 8, bmap);
+	time = ktime_get() - time;
+
+	if (ret != slen) {
+		pr_err("scnprintf(\"%%*pbl\"): result is %d, expected %d\n", ret, slen);
+		failed_tests++;
+		goto out;
+	}
+
+	if (strncmp(buf, expected, slen)) {
+		pr_err("scnprintf(\"%%*pbl\"): result is %s, expected %s\n", buf, expected);
+		failed_tests++;
+		goto out;
+	}
+
+	pr_info("scnprintf(\"%%*pbl\", '%s'):\t%llu\n", buf, time);
+out:
+	kfree(buf);
+	kfree(bmap);
+}
+
+static const unsigned long parse_test[] __initconst = {
+	BITMAP_FROM_U64(0),
+	BITMAP_FROM_U64(1),
+	BITMAP_FROM_U64(0xdeadbeef),
+	BITMAP_FROM_U64(0x100000000ULL),
+};
+
+static const unsigned long parse_test2[] __initconst = {
+	BITMAP_FROM_U64(0x100000000ULL), BITMAP_FROM_U64(0xdeadbeef),
+	BITMAP_FROM_U64(0x100000000ULL), BITMAP_FROM_U64(0xbaadf00ddeadbeef),
+	BITMAP_FROM_U64(0x100000000ULL), BITMAP_FROM_U64(0x0badf00ddeadbeef),
+};
+
+static const struct test_bitmap_parselist parse_tests[] __initconst = {
+	{0, "",				&parse_test[0 * step], 32, 0},
+	{0, " ",			&parse_test[0 * step], 32, 0},
+	{0, "0",			&parse_test[0 * step], 32, 0},
+	{0, "0\n",			&parse_test[0 * step], 32, 0},
+	{0, "1",			&parse_test[1 * step], 32, 0},
+	{0, "deadbeef",			&parse_test[2 * step], 32, 0},
+	{0, "1,0",			&parse_test[3 * step], 33, 0},
+	{0, "deadbeef,\n,0,1",		&parse_test[2 * step], 96, 0},
+
+	{0, "deadbeef,1,0",		&parse_test2[0 * 2 * step], 96, 0},
+	{0, "baadf00d,deadbeef,1,0",	&parse_test2[1 * 2 * step], 128, 0},
+	{0, "badf00d,deadbeef,1,0",	&parse_test2[2 * 2 * step], 124, 0},
+	{0, "badf00d,deadbeef,1,0",	&parse_test2[2 * 2 * step], 124, NO_LEN},
+	{0, "  badf00d,deadbeef,1,0  ",	&parse_test2[2 * 2 * step], 124, 0},
+	{0, " , badf00d,deadbeef,1,0 , ",	&parse_test2[2 * 2 * step], 124, 0},
+	{0, " , badf00d, ,, ,,deadbeef,1,0 , ",	&parse_test2[2 * 2 * step], 124, 0},
+
+	{-EINVAL,    "goodfood,deadbeef,1,0",	NULL, 128, 0},
+	{-EOVERFLOW, "3,0",			NULL, 33, 0},
+	{-EOVERFLOW, "123badf00d,deadbeef,1,0",	NULL, 128, 0},
+	{-EOVERFLOW, "badf00d,deadbeef,1,0",	NULL, 90, 0},
+	{-EOVERFLOW, "fbadf00d,deadbeef,1,0",	NULL, 95, 0},
+	{-EOVERFLOW, "badf00d,deadbeef,1,0",	NULL, 100, 0},
+#undef step
+};
+
+static void __init test_bitmap_parse(void)
+{
+	int i;
+	int err;
+	ktime_t time;
+	DECLARE_BITMAP(bmap, 2048);
+
+	for (i = 0; i < ARRAY_SIZE(parse_tests); i++) {
+		struct test_bitmap_parselist test = parse_tests[i];
+		size_t len = test.flags & NO_LEN ? UINT_MAX : strlen(test.in);
+
+		time = ktime_get();
+		err = bitmap_parse(test.in, len, bmap, test.nbits);
+		time = ktime_get() - time;
+
+		if (err != test.errno) {
+			pr_err("parse: %d: input is %s, errno is %d, expected %d\n",
+					i, test.in, err, test.errno);
+			failed_tests++;
+			continue;
+		}
+
+		if (!err && test.expected
+			 && !__bitmap_equal(bmap, test.expected, test.nbits)) {
+			pr_err("parse: %d: input is %s, result is 0x%lx, expected 0x%lx\n",
+					i, test.in, bmap[0],
+					*test.expected);
+			failed_tests++;
+			continue;
+		}
+
+		if (test.flags & PARSE_TIME)
+			pr_info("parse: %d: input is '%s' OK, Time: %llu\n",
+					i, test.in, time);
+	}
+}
+
+static void __init test_bitmap_arr32(void)
+{
+	unsigned int nbits, next_bit;
+	u32 arr[EXP1_IN_BITS / 32];
+	DECLARE_BITMAP(bmap2, EXP1_IN_BITS);
+
+	memset(arr, 0xa5, sizeof(arr));
+
+	for (nbits = 1; nbits < EXP1_IN_BITS; ++nbits) {
+		bitmap_to_arr32(arr, exp1, nbits);
+		bitmap_from_arr32(bmap2, arr, nbits);
+		expect_eq_bitmap(bmap2, exp1, nbits);
+
+		next_bit = find_next_bit(bmap2,
+				round_up(nbits, BITS_PER_LONG), nbits);
+		if (next_bit < round_up(nbits, BITS_PER_LONG)) {
+			pr_err("bitmap_copy_arr32(nbits == %d:"
+				" tail is not safely cleared: %d\n",
+				nbits, next_bit);
+			failed_tests++;
+		}
+
+		if (nbits < EXP1_IN_BITS - 32)
+			expect_eq_uint(arr[DIV_ROUND_UP(nbits, 32)],
+								0xa5a5a5a5);
+	}
+}
+
+static void __init test_bitmap_arr64(void)
+{
+	unsigned int nbits, next_bit;
+	u64 arr[EXP1_IN_BITS / 64];
+	DECLARE_BITMAP(bmap2, EXP1_IN_BITS);
+
+	memset(arr, 0xa5, sizeof(arr));
+
+	for (nbits = 1; nbits < EXP1_IN_BITS; ++nbits) {
+		memset(bmap2, 0xff, sizeof(arr));
+		bitmap_to_arr64(arr, exp1, nbits);
+		bitmap_from_arr64(bmap2, arr, nbits);
+		expect_eq_bitmap(bmap2, exp1, nbits);
+
+		next_bit = find_next_bit(bmap2, round_up(nbits, BITS_PER_LONG), nbits);
+		if (next_bit < round_up(nbits, BITS_PER_LONG)) {
+			pr_err("bitmap_copy_arr64(nbits == %d:"
+				" tail is not safely cleared: %d\n", nbits, next_bit);
+			failed_tests++;
+		}
+
+		if ((nbits % 64) &&
+		    (arr[(nbits - 1) / 64] & ~GENMASK_ULL((nbits - 1) % 64, 0))) {
+			pr_err("bitmap_to_arr64(nbits == %d): tail is not safely cleared: 0x%016llx (must be 0x%016llx)\n",
+			       nbits, arr[(nbits - 1) / 64],
+			       GENMASK_ULL((nbits - 1) % 64, 0));
+			failed_tests++;
+		}
+
+		if (nbits < EXP1_IN_BITS - 64)
+			expect_eq_uint(arr[DIV_ROUND_UP(nbits, 64)], 0xa5a5a5a5);
+	}
+}
+
+static void noinline __init test_mem_optimisations(void)
+{
+	DECLARE_BITMAP(bmap1, 1024);
+	DECLARE_BITMAP(bmap2, 1024);
+	unsigned int start, nbits;
+
+	for (start = 0; start < 1024; start += 8) {
+		for (nbits = 1; nbits < 1024 - start; nbits += 8) {
+			memset(bmap1, 0x5a, sizeof(bmap1));
+			memset(bmap2, 0x5a, sizeof(bmap2));
+
+			bitmap_set(bmap1, start, nbits);
+			__bitmap_set(bmap2, start, nbits);
+			if (!bitmap_equal(bmap1, bmap2, 1024)) {
+				printk("set not equal %d %d\n", start, nbits);
+				failed_tests++;
+			}
+			if (!__bitmap_equal(bmap1, bmap2, 1024)) {
+				printk("set not __equal %d %d\n", start, nbits);
+				failed_tests++;
+			}
+
+			bitmap_clear(bmap1, start, nbits);
+			__bitmap_clear(bmap2, start, nbits);
+			if (!bitmap_equal(bmap1, bmap2, 1024)) {
+				printk("clear not equal %d %d\n", start, nbits);
+				failed_tests++;
+			}
+			if (!__bitmap_equal(bmap1, bmap2, 1024)) {
+				printk("clear not __equal %d %d\n", start,
+									nbits);
+				failed_tests++;
+			}
+		}
+	}
+}
+
+static const unsigned char clump_exp[] __initconst = {
+	0x01,	/* 1 bit set */
+	0x02,	/* non-edge 1 bit set */
+	0x00,	/* zero bits set */
+	0x38,	/* 3 bits set across 4-bit boundary */
+	0x38,	/* Repeated clump */
+	0x0F,	/* 4 bits set */
+	0xFF,	/* all bits set */
+	0x05,	/* non-adjacent 2 bits set */
+};
+
+static void __init test_for_each_set_clump8(void)
+{
+#define CLUMP_EXP_NUMBITS 64
+	DECLARE_BITMAP(bits, CLUMP_EXP_NUMBITS);
+	unsigned int start;
+	unsigned long clump;
+
+	/* set bitmap to test case */
+	bitmap_zero(bits, CLUMP_EXP_NUMBITS);
+	bitmap_set(bits, 0, 1);		/* 0x01 */
+	bitmap_set(bits, 9, 1);		/* 0x02 */
+	bitmap_set(bits, 27, 3);	/* 0x28 */
+	bitmap_set(bits, 35, 3);	/* 0x28 */
+	bitmap_set(bits, 40, 4);	/* 0x0F */
+	bitmap_set(bits, 48, 8);	/* 0xFF */
+	bitmap_set(bits, 56, 1);	/* 0x05 - part 1 */
+	bitmap_set(bits, 58, 1);	/* 0x05 - part 2 */
+
+	for_each_set_clump8(start, clump, bits, CLUMP_EXP_NUMBITS)
+		expect_eq_clump8(start, CLUMP_EXP_NUMBITS, clump_exp, &clump);
+}
+
+static void __init test_for_each_set_bit_wrap(void)
+{
+	DECLARE_BITMAP(orig, 500);
+	DECLARE_BITMAP(copy, 500);
+	unsigned int wr, bit;
+
+	bitmap_zero(orig, 500);
+
+	/* Set individual bits */
+	for (bit = 0; bit < 500; bit += 10)
+		bitmap_set(orig, bit, 1);
+
+	/* Set range of bits */
+	bitmap_set(orig, 100, 50);
+
+	for (wr = 0; wr < 500; wr++) {
+		bitmap_zero(copy, 500);
+
+		for_each_set_bit_wrap(bit, orig, 500, wr)
+			bitmap_set(copy, bit, 1);
+
+		expect_eq_bitmap(orig, copy, 500);
+	}
+}
+
+static void __init test_for_each_set_bit(void)
+{
+	DECLARE_BITMAP(orig, 500);
+	DECLARE_BITMAP(copy, 500);
+	unsigned int bit;
+
+	bitmap_zero(orig, 500);
+	bitmap_zero(copy, 500);
+
+	/* Set individual bits */
+	for (bit = 0; bit < 500; bit += 10)
+		bitmap_set(orig, bit, 1);
+
+	/* Set range of bits */
+	bitmap_set(orig, 100, 50);
+
+	for_each_set_bit(bit, orig, 500)
+		bitmap_set(copy, bit, 1);
+
+	expect_eq_bitmap(orig, copy, 500);
+}
+
+static void __init test_for_each_set_bit_from(void)
+{
+	DECLARE_BITMAP(orig, 500);
+	DECLARE_BITMAP(copy, 500);
+	unsigned int wr, bit;
+
+	bitmap_zero(orig, 500);
+
+	/* Set individual bits */
+	for (bit = 0; bit < 500; bit += 10)
+		bitmap_set(orig, bit, 1);
+
+	/* Set range of bits */
+	bitmap_set(orig, 100, 50);
+
+	for (wr = 0; wr < 500; wr++) {
+		DECLARE_BITMAP(tmp, 500);
+
+		bitmap_zero(copy, 500);
+		bit = wr;
+
+		for_each_set_bit_from(bit, orig, 500)
+			bitmap_set(copy, bit, 1);
+
+		bitmap_copy(tmp, orig, 500);
+		bitmap_clear(tmp, 0, wr);
+		expect_eq_bitmap(tmp, copy, 500);
+	}
+}
+
+static void __init test_bitmap_weight(void)
+{
+	unsigned int bit, w1, w2, w;
+	DECLARE_BITMAP(b, 30);
+	DECLARE_BITMAP(b1, 128);
+
+	bitmap_parselist("all:1/2", b, 30);
+
+	/* Test inline implementation */
+	w = bitmap_weight(b, 30);
+	w1 = bitmap_weight(b, 15);
+	w2 = bitmap_weight_from(b, 15, 30);
+
+	expect_eq_uint(15, w);
+	expect_eq_uint(8, w1);
+	expect_eq_uint(7, w2);
+
+	/* Test outline implementation */
+	w = bitmap_weight(exp1, EXP1_IN_BITS);
+	for (bit = 1; bit < EXP1_IN_BITS; bit++) {
+		w1 = bitmap_weight(exp1, bit);
+		w2 = bitmap_weight_from(exp1, bit, EXP1_IN_BITS);
+		expect_eq_uint(w1 + w2, w);
+	}
+
+	/* Test out-of-range */
+	w = bitmap_weight_from(b, 31, 30);
+	expect_eq_uint(0, !!(w < 30));
+
+	/*
+	 * Test bitmap_weight() for correctness in case of some bits set between
+	 * nbits and end of the last word.
+	 */
+	bitmap_fill(b1, 128);
+
+	/* Inline */
+	expect_eq_uint(30, bitmap_weight(b1, 30));
+	expect_eq_uint(100, bitmap_weight(b1, 100));
+
+	/* Outline */
+	for (int i  = 1; i < 128; i++)
+		expect_eq_uint(i, bitmap_weight(b1, i));
+}
+
+static void __init test_for_each_clear_bit(void)
+{
+	DECLARE_BITMAP(orig, 500);
+	DECLARE_BITMAP(copy, 500);
+	unsigned int bit;
+
+	bitmap_fill(orig, 500);
+	bitmap_fill(copy, 500);
+
+	/* Set individual bits */
+	for (bit = 0; bit < 500; bit += 10)
+		bitmap_clear(orig, bit, 1);
+
+	/* Set range of bits */
+	bitmap_clear(orig, 100, 50);
+
+	for_each_clear_bit(bit, orig, 500)
+		bitmap_clear(copy, bit, 1);
+
+	expect_eq_bitmap(orig, copy, 500);
+}
+
+static void __init test_for_each_clear_bit_from(void)
+{
+	DECLARE_BITMAP(orig, 500);
+	DECLARE_BITMAP(copy, 500);
+	unsigned int wr, bit;
+
+	bitmap_fill(orig, 500);
+
+	/* Set individual bits */
+	for (bit = 0; bit < 500; bit += 10)
+		bitmap_clear(orig, bit, 1);
+
+	/* Set range of bits */
+	bitmap_clear(orig, 100, 50);
+
+	for (wr = 0; wr < 500; wr++) {
+		DECLARE_BITMAP(tmp, 500);
+
+		bitmap_fill(copy, 500);
+		bit = wr;
+
+		for_each_clear_bit_from(bit, orig, 500)
+			bitmap_clear(copy, bit, 1);
+
+		bitmap_copy(tmp, orig, 500);
+		bitmap_set(tmp, 0, wr);
+		expect_eq_bitmap(tmp, copy, 500);
+	}
+}
+
+static void __init test_for_each_set_bitrange(void)
+{
+	DECLARE_BITMAP(orig, 500);
+	DECLARE_BITMAP(copy, 500);
+	unsigned int s, e;
+
+	bitmap_zero(orig, 500);
+	bitmap_zero(copy, 500);
+
+	/* Set individual bits */
+	for (s = 0; s < 500; s += 10)
+		bitmap_set(orig, s, 1);
+
+	/* Set range of bits */
+	bitmap_set(orig, 100, 50);
+
+	for_each_set_bitrange(s, e, orig, 500)
+		bitmap_set(copy, s, e-s);
+
+	expect_eq_bitmap(orig, copy, 500);
+}
+
+static void __init test_for_each_clear_bitrange(void)
+{
+	DECLARE_BITMAP(orig, 500);
+	DECLARE_BITMAP(copy, 500);
+	unsigned int s, e;
+
+	bitmap_fill(orig, 500);
+	bitmap_fill(copy, 500);
+
+	/* Set individual bits */
+	for (s = 0; s < 500; s += 10)
+		bitmap_clear(orig, s, 1);
+
+	/* Set range of bits */
+	bitmap_clear(orig, 100, 50);
+
+	for_each_clear_bitrange(s, e, orig, 500)
+		bitmap_clear(copy, s, e-s);
+
+	expect_eq_bitmap(orig, copy, 500);
+}
+
+static void __init test_for_each_set_bitrange_from(void)
+{
+	DECLARE_BITMAP(orig, 500);
+	DECLARE_BITMAP(copy, 500);
+	unsigned int wr, s, e;
+
+	bitmap_zero(orig, 500);
+
+	/* Set individual bits */
+	for (s = 0; s < 500; s += 10)
+		bitmap_set(orig, s, 1);
+
+	/* Set range of bits */
+	bitmap_set(orig, 100, 50);
+
+	for (wr = 0; wr < 500; wr++) {
+		DECLARE_BITMAP(tmp, 500);
+
+		bitmap_zero(copy, 500);
+		s = wr;
+
+		for_each_set_bitrange_from(s, e, orig, 500)
+			bitmap_set(copy, s, e - s);
+
+		bitmap_copy(tmp, orig, 500);
+		bitmap_clear(tmp, 0, wr);
+		expect_eq_bitmap(tmp, copy, 500);
+	}
+}
+
+static void __init test_for_each_clear_bitrange_from(void)
+{
+	DECLARE_BITMAP(orig, 500);
+	DECLARE_BITMAP(copy, 500);
+	unsigned int wr, s, e;
+
+	bitmap_fill(orig, 500);
+
+	/* Set individual bits */
+	for (s = 0; s < 500; s += 10)
+		bitmap_clear(orig, s, 1);
+
+	/* Set range of bits */
+	bitmap_set(orig, 100, 50);
+
+	for (wr = 0; wr < 500; wr++) {
+		DECLARE_BITMAP(tmp, 500);
+
+		bitmap_fill(copy, 500);
+		s = wr;
+
+		for_each_clear_bitrange_from(s, e, orig, 500)
+			bitmap_clear(copy, s, e - s);
+
+		bitmap_copy(tmp, orig, 500);
+		bitmap_set(tmp, 0, wr);
+		expect_eq_bitmap(tmp, copy, 500);
+	}
+}
+
+struct test_bitmap_cut {
+	unsigned int first;
+	unsigned int cut;
+	unsigned int nbits;
+	unsigned long in[4];
+	unsigned long expected[4];
+};
+
+static struct test_bitmap_cut test_cut[] = {
+	{  0,  0,  8, { 0x0000000aUL, }, { 0x0000000aUL, }, },
+	{  0,  0, 32, { 0xdadadeadUL, }, { 0xdadadeadUL, }, },
+	{  0,  3,  8, { 0x000000aaUL, }, { 0x00000015UL, }, },
+	{  3,  3,  8, { 0x000000aaUL, }, { 0x00000012UL, }, },
+	{  0,  1, 32, { 0xa5a5a5a5UL, }, { 0x52d2d2d2UL, }, },
+	{  0,  8, 32, { 0xdeadc0deUL, }, { 0x00deadc0UL, }, },
+	{  1,  1, 32, { 0x5a5a5a5aUL, }, { 0x2d2d2d2cUL, }, },
+	{  0, 15, 32, { 0xa5a5a5a5UL, }, { 0x00014b4bUL, }, },
+	{  0, 16, 32, { 0xa5a5a5a5UL, }, { 0x0000a5a5UL, }, },
+	{ 15, 15, 32, { 0xa5a5a5a5UL, }, { 0x000125a5UL, }, },
+	{ 15, 16, 32, { 0xa5a5a5a5UL, }, { 0x0000a5a5UL, }, },
+	{ 16, 15, 32, { 0xa5a5a5a5UL, }, { 0x0001a5a5UL, }, },
+
+	{ BITS_PER_LONG, BITS_PER_LONG, BITS_PER_LONG,
+		{ 0xa5a5a5a5UL, 0xa5a5a5a5UL, },
+		{ 0xa5a5a5a5UL, 0xa5a5a5a5UL, },
+	},
+	{ 1, BITS_PER_LONG - 1, BITS_PER_LONG,
+		{ 0xa5a5a5a5UL, 0xa5a5a5a5UL, },
+		{ 0x00000001UL, 0x00000001UL, },
+	},
+
+	{ 0, BITS_PER_LONG * 2, BITS_PER_LONG * 2 + 1,
+		{ 0xa5a5a5a5UL, 0x00000001UL, 0x00000001UL, 0x00000001UL },
+		{ 0x00000001UL, },
+	},
+	{ 16, BITS_PER_LONG * 2 + 1, BITS_PER_LONG * 2 + 1 + 16,
+		{ 0x0000ffffUL, 0x5a5a5a5aUL, 0x5a5a5a5aUL, 0x5a5a5a5aUL },
+		{ 0x2d2dffffUL, },
+	},
+};
+
+static void __init test_bitmap_cut(void)
+{
+	unsigned long b[5], *in = &b[1], *out = &b[0];	/* Partial overlap */
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(test_cut); i++) {
+		struct test_bitmap_cut *t = &test_cut[i];
+
+		memcpy(in, t->in, sizeof(t->in));
+
+		bitmap_cut(out, in, t->first, t->cut, t->nbits);
+
+		expect_eq_bitmap(t->expected, out, t->nbits);
+	}
+}
+
+struct test_bitmap_print {
+	const unsigned long *bitmap;
+	unsigned long nbits;
+	const char *mask;
+	const char *list;
+};
+
+static const unsigned long small_bitmap[] __initconst = {
+	BITMAP_FROM_U64(0x3333333311111111ULL),
+};
+
+static const char small_mask[] __initconst = "33333333,11111111\n";
+static const char small_list[] __initconst = "0,4,8,12,16,20,24,28,32-33,36-37,40-41,44-45,48-49,52-53,56-57,60-61\n";
+
+static const unsigned long large_bitmap[] __initconst = {
+	BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+	BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+	BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+	BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+	BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+	BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+	BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+	BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+	BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+	BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+	BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+	BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+	BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+	BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+	BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+	BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+	BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+	BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+	BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+	BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+};
+
+static const char large_mask[] __initconst = "33333333,11111111,33333333,11111111,"
+					"33333333,11111111,33333333,11111111,"
+					"33333333,11111111,33333333,11111111,"
+					"33333333,11111111,33333333,11111111,"
+					"33333333,11111111,33333333,11111111,"
+					"33333333,11111111,33333333,11111111,"
+					"33333333,11111111,33333333,11111111,"
+					"33333333,11111111,33333333,11111111,"
+					"33333333,11111111,33333333,11111111,"
+					"33333333,11111111,33333333,11111111,"
+					"33333333,11111111,33333333,11111111,"
+					"33333333,11111111,33333333,11111111,"
+					"33333333,11111111,33333333,11111111,"
+					"33333333,11111111,33333333,11111111,"
+					"33333333,11111111,33333333,11111111,"
+					"33333333,11111111,33333333,11111111,"
+					"33333333,11111111,33333333,11111111,"
+					"33333333,11111111,33333333,11111111,"
+					"33333333,11111111,33333333,11111111,"
+					"33333333,11111111,33333333,11111111\n";
+
+static const char large_list[] __initconst = /* more than 4KB */
+	"0,4,8,12,16,20,24,28,32-33,36-37,40-41,44-45,48-49,52-53,56-57,60-61,64,68,72,76,80,84,88,92,96-97,100-101,104-1"
+	"05,108-109,112-113,116-117,120-121,124-125,128,132,136,140,144,148,152,156,160-161,164-165,168-169,172-173,176-1"
+	"77,180-181,184-185,188-189,192,196,200,204,208,212,216,220,224-225,228-229,232-233,236-237,240-241,244-245,248-2"
+	"49,252-253,256,260,264,268,272,276,280,284,288-289,292-293,296-297,300-301,304-305,308-309,312-313,316-317,320,3"
+	"24,328,332,336,340,344,348,352-353,356-357,360-361,364-365,368-369,372-373,376-377,380-381,384,388,392,396,400,4"
+	"04,408,412,416-417,420-421,424-425,428-429,432-433,436-437,440-441,444-445,448,452,456,460,464,468,472,476,480-4"
+	"81,484-485,488-489,492-493,496-497,500-501,504-505,508-509,512,516,520,524,528,532,536,540,544-545,548-549,552-5"
+	"53,556-557,560-561,564-565,568-569,572-573,576,580,584,588,592,596,600,604,608-609,612-613,616-617,620-621,624-6"
+	"25,628-629,632-633,636-637,640,644,648,652,656,660,664,668,672-673,676-677,680-681,684-685,688-689,692-693,696-6"
+	"97,700-701,704,708,712,716,720,724,728,732,736-737,740-741,744-745,748-749,752-753,756-757,760-761,764-765,768,7"
+	"72,776,780,784,788,792,796,800-801,804-805,808-809,812-813,816-817,820-821,824-825,828-829,832,836,840,844,848,8"
+	"52,856,860,864-865,868-869,872-873,876-877,880-881,884-885,888-889,892-893,896,900,904,908,912,916,920,924,928-9"
+	"29,932-933,936-937,940-941,944-945,948-949,952-953,956-957,960,964,968,972,976,980,984,988,992-993,996-997,1000-"
+	"1001,1004-1005,1008-1009,1012-1013,1016-1017,1020-1021,1024,1028,1032,1036,1040,1044,1048,1052,1056-1057,1060-10"
+	"61,1064-1065,1068-1069,1072-1073,1076-1077,1080-1081,1084-1085,1088,1092,1096,1100,1104,1108,1112,1116,1120-1121"
+	",1124-1125,1128-1129,1132-1133,1136-1137,1140-1141,1144-1145,1148-1149,1152,1156,1160,1164,1168,1172,1176,1180,1"
+	"184-1185,1188-1189,1192-1193,1196-1197,1200-1201,1204-1205,1208-1209,1212-1213,1216,1220,1224,1228,1232,1236,124"
+	"0,1244,1248-1249,1252-1253,1256-1257,1260-1261,1264-1265,1268-1269,1272-1273,1276-1277,1280,1284,1288,1292,1296,"
+	"1300,1304,1308,1312-1313,1316-1317,1320-1321,1324-1325,1328-1329,1332-1333,1336-1337,1340-1341,1344,1348,1352,13"
+	"56,1360,1364,1368,1372,1376-1377,1380-1381,1384-1385,1388-1389,1392-1393,1396-1397,1400-1401,1404-1405,1408,1412"
+	",1416,1420,1424,1428,1432,1436,1440-1441,1444-1445,1448-1449,1452-1453,1456-1457,1460-1461,1464-1465,1468-1469,1"
+	"472,1476,1480,1484,1488,1492,1496,1500,1504-1505,1508-1509,1512-1513,1516-1517,1520-1521,1524-1525,1528-1529,153"
+	"2-1533,1536,1540,1544,1548,1552,1556,1560,1564,1568-1569,1572-1573,1576-1577,1580-1581,1584-1585,1588-1589,1592-"
+	"1593,1596-1597,1600,1604,1608,1612,1616,1620,1624,1628,1632-1633,1636-1637,1640-1641,1644-1645,1648-1649,1652-16"
+	"53,1656-1657,1660-1661,1664,1668,1672,1676,1680,1684,1688,1692,1696-1697,1700-1701,1704-1705,1708-1709,1712-1713"
+	",1716-1717,1720-1721,1724-1725,1728,1732,1736,1740,1744,1748,1752,1756,1760-1761,1764-1765,1768-1769,1772-1773,1"
+	"776-1777,1780-1781,1784-1785,1788-1789,1792,1796,1800,1804,1808,1812,1816,1820,1824-1825,1828-1829,1832-1833,183"
+	"6-1837,1840-1841,1844-1845,1848-1849,1852-1853,1856,1860,1864,1868,1872,1876,1880,1884,1888-1889,1892-1893,1896-"
+	"1897,1900-1901,1904-1905,1908-1909,1912-1913,1916-1917,1920,1924,1928,1932,1936,1940,1944,1948,1952-1953,1956-19"
+	"57,1960-1961,1964-1965,1968-1969,1972-1973,1976-1977,1980-1981,1984,1988,1992,1996,2000,2004,2008,2012,2016-2017"
+	",2020-2021,2024-2025,2028-2029,2032-2033,2036-2037,2040-2041,2044-2045,2048,2052,2056,2060,2064,2068,2072,2076,2"
+	"080-2081,2084-2085,2088-2089,2092-2093,2096-2097,2100-2101,2104-2105,2108-2109,2112,2116,2120,2124,2128,2132,213"
+	"6,2140,2144-2145,2148-2149,2152-2153,2156-2157,2160-2161,2164-2165,2168-2169,2172-2173,2176,2180,2184,2188,2192,"
+	"2196,2200,2204,2208-2209,2212-2213,2216-2217,2220-2221,2224-2225,2228-2229,2232-2233,2236-2237,2240,2244,2248,22"
+	"52,2256,2260,2264,2268,2272-2273,2276-2277,2280-2281,2284-2285,2288-2289,2292-2293,2296-2297,2300-2301,2304,2308"
+	",2312,2316,2320,2324,2328,2332,2336-2337,2340-2341,2344-2345,2348-2349,2352-2353,2356-2357,2360-2361,2364-2365,2"
+	"368,2372,2376,2380,2384,2388,2392,2396,2400-2401,2404-2405,2408-2409,2412-2413,2416-2417,2420-2421,2424-2425,242"
+	"8-2429,2432,2436,2440,2444,2448,2452,2456,2460,2464-2465,2468-2469,2472-2473,2476-2477,2480-2481,2484-2485,2488-"
+	"2489,2492-2493,2496,2500,2504,2508,2512,2516,2520,2524,2528-2529,2532-2533,2536-2537,2540-2541,2544-2545,2548-25"
+	"49,2552-2553,2556-2557\n";
+
+static const struct test_bitmap_print test_print[] __initconst = {
+	{ small_bitmap, sizeof(small_bitmap) * BITS_PER_BYTE, small_mask, small_list },
+	{ large_bitmap, sizeof(large_bitmap) * BITS_PER_BYTE, large_mask, large_list },
+};
+
+static void __init test_bitmap_print_buf(void)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(test_print); i++) {
+		const struct test_bitmap_print *t = &test_print[i];
+		int n;
+
+		n = bitmap_print_bitmask_to_buf(print_buf, t->bitmap, t->nbits,
+						0, 2 * PAGE_SIZE);
+		expect_eq_uint(strlen(t->mask) + 1, n);
+		expect_eq_str(t->mask, print_buf, n);
+
+		n = bitmap_print_list_to_buf(print_buf, t->bitmap, t->nbits,
+					     0, 2 * PAGE_SIZE);
+		expect_eq_uint(strlen(t->list) + 1, n);
+		expect_eq_str(t->list, print_buf, n);
+
+		/* test by non-zero offset */
+		if (strlen(t->list) > PAGE_SIZE) {
+			n = bitmap_print_list_to_buf(print_buf, t->bitmap, t->nbits,
+						     PAGE_SIZE, PAGE_SIZE);
+			expect_eq_uint(strlen(t->list) + 1 - PAGE_SIZE, n);
+			expect_eq_str(t->list + PAGE_SIZE, print_buf, n);
+		}
+	}
+}
+
+/*
+ * FIXME: Clang breaks compile-time evaluations when KASAN and GCOV are enabled.
+ * To workaround it, GCOV is force-disabled in Makefile for this configuration.
+ */
+static void __init test_bitmap_const_eval(void)
+{
+	DECLARE_BITMAP(bitmap, BITS_PER_LONG);
+	unsigned long initvar = BIT(2);
+	unsigned long bitopvar = 0;
+	unsigned long var = 0;
+	int res;
+
+	/*
+	 * Compilers must be able to optimize all of those to compile-time
+	 * constants on any supported optimization level (-O2, -Os) and any
+	 * architecture. Otherwise, trigger a build bug.
+	 * The whole function gets optimized out then, there's nothing to do
+	 * in runtime.
+	 */
+
+	/* Equals to `unsigned long bitmap[1] = { GENMASK(6, 5), }` */
+	bitmap_clear(bitmap, 0, BITS_PER_LONG);
+	if (!test_bit(7, bitmap))
+		bitmap_set(bitmap, 5, 2);
+
+	/* Equals to `unsigned long bitopvar = BIT(20)` */
+	__change_bit(31, &bitopvar);
+	bitmap_shift_right(&bitopvar, &bitopvar, 11, BITS_PER_LONG);
+
+	/* Equals to `unsigned long var = BIT(25)` */
+	var |= BIT(25);
+	if (var & BIT(0))
+		var ^= GENMASK(9, 6);
+
+	/* __const_hweight<32|64>(GENMASK(6, 5)) == 2 */
+	res = bitmap_weight(bitmap, 20);
+	BUILD_BUG_ON(!__builtin_constant_p(res));
+	BUILD_BUG_ON(res != 2);
+
+	/* !(BIT(31) & BIT(18)) == 1 */
+	res = !test_bit(18, &bitopvar);
+	BUILD_BUG_ON(!__builtin_constant_p(res));
+	BUILD_BUG_ON(!res);
+
+	/* BIT(2) & GENMASK(14, 8) == 0 */
+	res = initvar & GENMASK(14, 8);
+	BUILD_BUG_ON(!__builtin_constant_p(res));
+	BUILD_BUG_ON(res);
+
+	/* ~BIT(25) */
+	BUILD_BUG_ON(!__builtin_constant_p(~var));
+	BUILD_BUG_ON(~var != ~BIT(25));
+
+	/* ~BIT(25) | BIT(25) == ~0UL */
+	bitmap_complement(&var, &var, BITS_PER_LONG);
+	__assign_bit(25, &var, true);
+
+	/* !(~(~0UL)) == 1 */
+	res = bitmap_full(&var, BITS_PER_LONG);
+	BUILD_BUG_ON(!__builtin_constant_p(res));
+	BUILD_BUG_ON(!res);
+}
+
+/*
+ * Test bitmap should be big enough to include the cases when start is not in
+ * the first word, and start+nbits lands in the following word.
+ */
+#define TEST_BIT_LEN (1000)
+
+/*
+ * Helper function to test bitmap_write() overwriting the chosen byte pattern.
+ */
+static void __init test_bitmap_write_helper(const char *pattern)
+{
+	DECLARE_BITMAP(bitmap, TEST_BIT_LEN);
+	DECLARE_BITMAP(exp_bitmap, TEST_BIT_LEN);
+	DECLARE_BITMAP(pat_bitmap, TEST_BIT_LEN);
+	unsigned long w, r, bit;
+	int i, n, nbits;
+
+	/*
+	 * Only parse the pattern once and store the result in the intermediate
+	 * bitmap.
+	 */
+	bitmap_parselist(pattern, pat_bitmap, TEST_BIT_LEN);
+
+	/*
+	 * Check that writing a single bit does not accidentally touch the
+	 * adjacent bits.
+	 */
+	for (i = 0; i < TEST_BIT_LEN; i++) {
+		bitmap_copy(bitmap, pat_bitmap, TEST_BIT_LEN);
+		bitmap_copy(exp_bitmap, pat_bitmap, TEST_BIT_LEN);
+		for (bit = 0; bit <= 1; bit++) {
+			bitmap_write(bitmap, bit, i, 1);
+			__assign_bit(i, exp_bitmap, bit);
+			expect_eq_bitmap(exp_bitmap, bitmap,
+					 TEST_BIT_LEN);
+		}
+	}
+
+	/* Ensure writing 0 bits does not change anything. */
+	bitmap_copy(bitmap, pat_bitmap, TEST_BIT_LEN);
+	bitmap_copy(exp_bitmap, pat_bitmap, TEST_BIT_LEN);
+	for (i = 0; i < TEST_BIT_LEN; i++) {
+		bitmap_write(bitmap, ~0UL, i, 0);
+		expect_eq_bitmap(exp_bitmap, bitmap, TEST_BIT_LEN);
+	}
+
+	for (nbits = BITS_PER_LONG; nbits >= 1; nbits--) {
+		w = IS_ENABLED(CONFIG_64BIT) ? 0xdeadbeefdeadbeefUL
+					     : 0xdeadbeefUL;
+		w >>= (BITS_PER_LONG - nbits);
+		for (i = 0; i <= TEST_BIT_LEN - nbits; i++) {
+			bitmap_copy(bitmap, pat_bitmap, TEST_BIT_LEN);
+			bitmap_copy(exp_bitmap, pat_bitmap, TEST_BIT_LEN);
+			for (n = 0; n < nbits; n++)
+				__assign_bit(i + n, exp_bitmap, w & BIT(n));
+			bitmap_write(bitmap, w, i, nbits);
+			expect_eq_bitmap(exp_bitmap, bitmap, TEST_BIT_LEN);
+			r = bitmap_read(bitmap, i, nbits);
+			expect_eq_ulong(r, w);
+		}
+	}
+}
+
+static void __init test_bitmap_read_write(void)
+{
+	unsigned char *pattern[3] = {"", "all:1/2", "all"};
+	DECLARE_BITMAP(bitmap, TEST_BIT_LEN);
+	unsigned long zero_bits = 0, bits_per_long = BITS_PER_LONG;
+	unsigned long val;
+	int i, pi;
+
+	/*
+	 * Reading/writing zero bits should not crash the kernel.
+	 * READ_ONCE() prevents constant folding.
+	 */
+	bitmap_write(NULL, 0, 0, READ_ONCE(zero_bits));
+	/* Return value of bitmap_read() is undefined here. */
+	bitmap_read(NULL, 0, READ_ONCE(zero_bits));
+
+	/*
+	 * Reading/writing more than BITS_PER_LONG bits should not crash the
+	 * kernel. READ_ONCE() prevents constant folding.
+	 */
+	bitmap_write(NULL, 0, 0, READ_ONCE(bits_per_long) + 1);
+	/* Return value of bitmap_read() is undefined here. */
+	bitmap_read(NULL, 0, READ_ONCE(bits_per_long) + 1);
+
+	/*
+	 * Ensure that bitmap_read() reads the same value that was previously
+	 * written, and two consequent values are correctly merged.
+	 * The resulting bit pattern is asymmetric to rule out possible issues
+	 * with bit numeration order.
+	 */
+	for (i = 0; i < TEST_BIT_LEN - 7; i++) {
+		bitmap_zero(bitmap, TEST_BIT_LEN);
+
+		bitmap_write(bitmap, 0b10101UL, i, 5);
+		val = bitmap_read(bitmap, i, 5);
+		expect_eq_ulong(0b10101UL, val);
+
+		bitmap_write(bitmap, 0b101UL, i + 5, 3);
+		val = bitmap_read(bitmap, i + 5, 3);
+		expect_eq_ulong(0b101UL, val);
+
+		val = bitmap_read(bitmap, i, 8);
+		expect_eq_ulong(0b10110101UL, val);
+	}
+
+	for (pi = 0; pi < ARRAY_SIZE(pattern); pi++)
+		test_bitmap_write_helper(pattern[pi]);
+}
+
+static void __init test_bitmap_read_perf(void)
+{
+	DECLARE_BITMAP(bitmap, TEST_BIT_LEN);
+	unsigned int cnt, nbits, i;
+	unsigned long val;
+	ktime_t time;
+
+	bitmap_fill(bitmap, TEST_BIT_LEN);
+	time = ktime_get();
+	for (cnt = 0; cnt < 5; cnt++) {
+		for (nbits = 1; nbits <= BITS_PER_LONG; nbits++) {
+			for (i = 0; i < TEST_BIT_LEN; i++) {
+				if (i + nbits > TEST_BIT_LEN)
+					break;
+				/*
+				 * Prevent the compiler from optimizing away the
+				 * bitmap_read() by using its value.
+				 */
+				WRITE_ONCE(val, bitmap_read(bitmap, i, nbits));
+			}
+		}
+	}
+	time = ktime_get() - time;
+	pr_info("%s:\t\t%llu\n", __func__, time);
+}
+
+static void __init test_bitmap_write_perf(void)
+{
+	DECLARE_BITMAP(bitmap, TEST_BIT_LEN);
+	unsigned int cnt, nbits, i;
+	unsigned long val = 0xfeedface;
+	ktime_t time;
+
+	bitmap_zero(bitmap, TEST_BIT_LEN);
+	time = ktime_get();
+	for (cnt = 0; cnt < 5; cnt++) {
+		for (nbits = 1; nbits <= BITS_PER_LONG; nbits++) {
+			for (i = 0; i < TEST_BIT_LEN; i++) {
+				if (i + nbits > TEST_BIT_LEN)
+					break;
+				bitmap_write(bitmap, val, i, nbits);
+			}
+		}
+	}
+	time = ktime_get() - time;
+	pr_info("%s:\t\t%llu\n", __func__, time);
+}
+
+/*
+ * nbits == 0 is most commonly not a valid case. Bitmap users should revisit
+ * the caller logic. Bitmap API doesn't provide any guarantees on returned
+ * value. The pointers are not dereferenced. The return value is intentionally
+ * ignored.
+ */
+static void __init test_zero_nbits(void)
+{
+	static volatile __always_used unsigned long ret __initdata;
+
+	bitmap_clear(NULL, 0, 0);
+	bitmap_complement(NULL, NULL, 0);
+	bitmap_copy(NULL, NULL, 0);
+	bitmap_copy_clear_tail(NULL, NULL, 0);
+	bitmap_fill(NULL, 0);
+	bitmap_from_arr32(NULL, NULL, 0);
+	bitmap_from_arr64(NULL, NULL, 0);
+	bitmap_or(NULL, NULL, NULL, 0);
+	bitmap_set(NULL, 0, 0);
+	bitmap_shift_left(NULL, NULL, 0, 0);
+	bitmap_shift_right(NULL, NULL, 0, 0);
+	bitmap_to_arr32(NULL, NULL, 0);
+	bitmap_to_arr64(NULL, NULL, 0);
+	bitmap_write(NULL, 0, 0, 0);
+	bitmap_xor(NULL, NULL, NULL, 0);
+	bitmap_zero(NULL, 0);
+
+	ret = bitmap_and(NULL, NULL, NULL, 0);
+	ret = bitmap_empty(NULL, 0);
+	ret = bitmap_equal(NULL, NULL, 0);
+	ret = bitmap_full(NULL, 0);
+	ret = bitmap_or_equal(NULL, NULL, NULL, 0);
+	ret = bitmap_read(NULL, 0, 0);
+	ret = bitmap_subset(NULL, NULL, 0);
+	ret = bitmap_weight(NULL, 0);
+	ret = bitmap_weight_and(NULL, NULL, 0);
+	ret = bitmap_weight_andnot(NULL, NULL, 0);
+	ret = bitmap_weight_from(NULL, 0, 0);
+	ret = bitmap_weighted_or(NULL, NULL, NULL, 0);
+
+	ret = find_first_and_and_bit(NULL, NULL, NULL, 0);
+	ret = find_first_and_bit(NULL, NULL, 0);
+	ret = find_first_andnot_bit(NULL, NULL, 0);
+	ret = find_first_bit(NULL, 0);
+	ret = find_first_zero_bit(NULL, 0);
+	ret = find_last_bit(NULL, 0);
+	ret = find_next_and_bit(NULL, NULL, 0, 0);
+	ret = find_next_andnot_bit(NULL, NULL, 0, 0);
+	ret = find_next_bit(NULL, 0, 0);
+	ret = find_next_clump8(NULL, NULL, 0, 0);
+	ret = find_next_zero_bit(NULL, 0, 0);
+	ret = find_nth_and_bit(NULL, NULL, 0, 0);
+	ret = find_nth_bit(NULL, 0, 0);
+	ret = find_random_bit(NULL, 0);
+}
+
+#undef TEST_BIT_LEN
+
+static void __init selftest(void)
+{
+	test_zero_clear();
+	test_fill_set();
+	test_copy();
+	test_bitmap_region();
+	test_replace();
+	test_bitmap_sg();
+	test_bitmap_arr32();
+	test_bitmap_arr64();
+	test_bitmap_parse();
+	test_bitmap_parselist();
+	test_bitmap_printlist();
+	test_mem_optimisations();
+	test_bitmap_cut();
+	test_bitmap_print_buf();
+	test_bitmap_const_eval();
+	test_bitmap_read_write();
+	test_bitmap_read_perf();
+	test_bitmap_weight();
+	test_bitmap_write_perf();
+	test_zero_nbits();
+
+	test_find_nth_bit();
+	test_for_each_set_bit();
+	test_for_each_set_bit_from();
+	test_for_each_clear_bit();
+	test_for_each_clear_bit_from();
+	test_for_each_set_bitrange();
+	test_for_each_clear_bitrange();
+	test_for_each_set_bitrange_from();
+	test_for_each_clear_bitrange_from();
+	test_for_each_set_clump8();
+	test_for_each_set_bit_wrap();
+	test_bitmap_find_next_zero_area_off();
+}
+
+KSTM_MODULE_LOADERS(test_bitmap);
+MODULE_AUTHOR("david decotigny <david.decotigny@googlers.com>");
+MODULE_DESCRIPTION("Test cases for bitmap API");
+MODULE_LICENSE("GPL");