tools/testing/selftests/bpf/prog_tests/mmap.c - pub/scm/linux/kernel/git/legion/linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 #include <test_progs.h>
 #include <sys/mman.h>
 #include "test_mmap.skel.h"

 struct map_data {
 	__u64 val[512 * 4];
 };

 static size_t roundup_page(size_t sz)
 {
 	long page_size = sysconf(_SC_PAGE_SIZE);
 	return (sz + page_size - 1) / page_size * page_size;
 }

 void test_mmap(void)
 {
 	const size_t bss_sz = roundup_page(sizeof(struct test_mmap__bss));
 	const size_t map_sz = roundup_page(sizeof(struct map_data));
 	const int zero = 0, one = 1, two = 2, far = 1500;
 	const long page_size = sysconf(_SC_PAGE_SIZE);
 	int err, duration = 0, i, data_map_fd, data_map_id, tmp_fd, rdmap_fd;
 	struct bpf_map *data_map, *bss_map;
 	void *bss_mmaped = NULL, *map_mmaped = NULL, *tmp0, *tmp1, *tmp2;
 	struct test_mmap__bss *bss_data;
 	struct bpf_map_info map_info;
 	__u32 map_info_sz = sizeof(map_info);
 	struct map_data *map_data;
 	struct test_mmap *skel;
 	__u64 val = 0;

 	skel = test_mmap__open_and_load();
 	if (CHECK(!skel, "skel_open_and_load", "skeleton open/load failed\n"))
 		return;

 	bss_map = skel->maps.bss;
 	data_map = skel->maps.data_map;
 	data_map_fd = bpf_map__fd(data_map);

 	rdmap_fd = bpf_map__fd(skel->maps.rdonly_map);
 	tmp1 = mmap(NULL, 4096, PROT_READ | PROT_WRITE, MAP_SHARED, rdmap_fd, 0);
 	if (CHECK(tmp1 != MAP_FAILED, "rdonly_write_mmap", "unexpected success\n")) {
 		munmap(tmp1, 4096);
 		goto cleanup;
 	}
 	/* now double-check if it's mmap()'able at all */
 	tmp1 = mmap(NULL, 4096, PROT_READ, MAP_SHARED, rdmap_fd, 0);
 	if (CHECK(tmp1 == MAP_FAILED, "rdonly_read_mmap", "failed: %d\n", errno))
 		goto cleanup;

 	/* get map's ID */
 	memset(&map_info, 0, map_info_sz);
 	err = bpf_obj_get_info_by_fd(data_map_fd, &map_info, &map_info_sz);
 	if (CHECK(err, "map_get_info", "failed %d\n", errno))
 		goto cleanup;
 	data_map_id = map_info.id;

 	/* mmap BSS map */
 	bss_mmaped = mmap(NULL, bss_sz, PROT_READ | PROT_WRITE, MAP_SHARED,
 			  bpf_map__fd(bss_map), 0);
 	if (CHECK(bss_mmaped == MAP_FAILED, "bss_mmap",
 		  ".bss mmap failed: %d\n", errno)) {
 		bss_mmaped = NULL;
 		goto cleanup;
 	}
 	/* map as R/W first */
 	map_mmaped = mmap(NULL, map_sz, PROT_READ | PROT_WRITE, MAP_SHARED,
 			  data_map_fd, 0);
 	if (CHECK(map_mmaped == MAP_FAILED, "data_mmap",
 		  "data_map mmap failed: %d\n", errno)) {
 		map_mmaped = NULL;
 		goto cleanup;
 	}

 	bss_data = bss_mmaped;
 	map_data = map_mmaped;

 	CHECK_FAIL(bss_data->in_val);
 	CHECK_FAIL(bss_data->out_val);
 	CHECK_FAIL(skel->bss->in_val);
 	CHECK_FAIL(skel->bss->out_val);
 	CHECK_FAIL(map_data->val[0]);
 	CHECK_FAIL(map_data->val[1]);
 	CHECK_FAIL(map_data->val[2]);
 	CHECK_FAIL(map_data->val[far]);

 	err = test_mmap__attach(skel);
 	if (CHECK(err, "attach_raw_tp", "err %d\n", err))
 		goto cleanup;

 	bss_data->in_val = 123;
 	val = 111;
 	CHECK_FAIL(bpf_map_update_elem(data_map_fd, &zero, &val, 0));

 	usleep(1);

 	CHECK_FAIL(bss_data->in_val != 123);
 	CHECK_FAIL(bss_data->out_val != 123);
 	CHECK_FAIL(skel->bss->in_val != 123);
 	CHECK_FAIL(skel->bss->out_val != 123);
 	CHECK_FAIL(map_data->val[0] != 111);
 	CHECK_FAIL(map_data->val[1] != 222);
 	CHECK_FAIL(map_data->val[2] != 123);
 	CHECK_FAIL(map_data->val[far] != 3 * 123);

 	CHECK_FAIL(bpf_map_lookup_elem(data_map_fd, &zero, &val));
 	CHECK_FAIL(val != 111);
 	CHECK_FAIL(bpf_map_lookup_elem(data_map_fd, &one, &val));
 	CHECK_FAIL(val != 222);
 	CHECK_FAIL(bpf_map_lookup_elem(data_map_fd, &two, &val));
 	CHECK_FAIL(val != 123);
 	CHECK_FAIL(bpf_map_lookup_elem(data_map_fd, &far, &val));
 	CHECK_FAIL(val != 3 * 123);

 	/* data_map freeze should fail due to R/W mmap() */
 	err = bpf_map_freeze(data_map_fd);
 	if (CHECK(!err || errno != EBUSY, "no_freeze",
 		  "data_map freeze succeeded: err=%d, errno=%d\n", err, errno))
 		goto cleanup;

 	err = mprotect(map_mmaped, map_sz, PROT_READ);
 	if (CHECK(err, "mprotect_ro", "mprotect to r/o failed %d\n", errno))
 		goto cleanup;

 	/* unmap R/W mapping */
 	err = munmap(map_mmaped, map_sz);
 	map_mmaped = NULL;
 	if (CHECK(err, "data_map_munmap", "data_map munmap failed: %d\n", errno))
 		goto cleanup;

 	/* re-map as R/O now */
 	map_mmaped = mmap(NULL, map_sz, PROT_READ, MAP_SHARED, data_map_fd, 0);
 	if (CHECK(map_mmaped == MAP_FAILED, "data_mmap",
 		  "data_map R/O mmap failed: %d\n", errno)) {
 		map_mmaped = NULL;
 		goto cleanup;
 	}
 	err = mprotect(map_mmaped, map_sz, PROT_WRITE);
 	if (CHECK(!err, "mprotect_wr", "mprotect() succeeded unexpectedly!\n"))
 		goto cleanup;
 	err = mprotect(map_mmaped, map_sz, PROT_EXEC);
 	if (CHECK(!err, "mprotect_ex", "mprotect() succeeded unexpectedly!\n"))
 		goto cleanup;
 	map_data = map_mmaped;

 	/* map/unmap in a loop to test ref counting */
 	for (i = 0; i < 10; i++) {
 		int flags = i % 2 ? PROT_READ : PROT_WRITE;
 		void *p;

 		p = mmap(NULL, map_sz, flags, MAP_SHARED, data_map_fd, 0);
 		if (CHECK_FAIL(p == MAP_FAILED))
 			goto cleanup;
 		err = munmap(p, map_sz);
 		if (CHECK_FAIL(err))
 			goto cleanup;
 	}

 	/* data_map freeze should now succeed due to no R/W mapping */
 	err = bpf_map_freeze(data_map_fd);
 	if (CHECK(err, "freeze", "data_map freeze failed: err=%d, errno=%d\n",
 		  err, errno))
 		goto cleanup;

 	/* mapping as R/W now should fail */
 	tmp1 = mmap(NULL, map_sz, PROT_READ | PROT_WRITE, MAP_SHARED,
 		    data_map_fd, 0);
 	if (CHECK(tmp1 != MAP_FAILED, "data_mmap", "mmap succeeded\n")) {
 		munmap(tmp1, map_sz);
 		goto cleanup;
 	}

 	bss_data->in_val = 321;
 	usleep(1);
 	CHECK_FAIL(bss_data->in_val != 321);
 	CHECK_FAIL(bss_data->out_val != 321);
 	CHECK_FAIL(skel->bss->in_val != 321);
 	CHECK_FAIL(skel->bss->out_val != 321);
 	CHECK_FAIL(map_data->val[0] != 111);
 	CHECK_FAIL(map_data->val[1] != 222);
 	CHECK_FAIL(map_data->val[2] != 321);
 	CHECK_FAIL(map_data->val[far] != 3 * 321);

 	/* check some more advanced mmap() manipulations */

 	tmp0 = mmap(NULL, 4 * page_size, PROT_READ, MAP_SHARED | MAP_ANONYMOUS,
 			  -1, 0);
 	if (CHECK(tmp0 == MAP_FAILED, "adv_mmap0", "errno %d\n", errno))
 		goto cleanup;

 	/* map all but last page: pages 1-3 mapped */
 	tmp1 = mmap(tmp0, 3 * page_size, PROT_READ, MAP_SHARED | MAP_FIXED,
 			  data_map_fd, 0);
 	if (CHECK(tmp0 != tmp1, "adv_mmap1", "tmp0: %p, tmp1: %p\n", tmp0, tmp1)) {
 		munmap(tmp0, 4 * page_size);
 		goto cleanup;
 	}

 	/* unmap second page: pages 1, 3 mapped */
 	err = munmap(tmp1 + page_size, page_size);
 	if (CHECK(err, "adv_mmap2", "errno %d\n", errno)) {
 		munmap(tmp1, 4 * page_size);
 		goto cleanup;
 	}

 	/* map page 2 back */
 	tmp2 = mmap(tmp1 + page_size, page_size, PROT_READ,
 		    MAP_SHARED | MAP_FIXED, data_map_fd, 0);
 	if (CHECK(tmp2 == MAP_FAILED, "adv_mmap3", "errno %d\n", errno)) {
 		munmap(tmp1, page_size);
 		munmap(tmp1 + 2*page_size, 2 * page_size);
 		goto cleanup;
 	}
 	CHECK(tmp1 + page_size != tmp2, "adv_mmap4",
 	      "tmp1: %p, tmp2: %p\n", tmp1, tmp2);

 	/* re-map all 4 pages */
 	tmp2 = mmap(tmp1, 4 * page_size, PROT_READ, MAP_SHARED | MAP_FIXED,
 		    data_map_fd, 0);
 	if (CHECK(tmp2 == MAP_FAILED, "adv_mmap5", "errno %d\n", errno)) {
 		munmap(tmp1, 4 * page_size); /* unmap page 1 */
 		goto cleanup;
 	}
 	CHECK(tmp1 != tmp2, "adv_mmap6", "tmp1: %p, tmp2: %p\n", tmp1, tmp2);

 	map_data = tmp2;
 	CHECK_FAIL(bss_data->in_val != 321);
 	CHECK_FAIL(bss_data->out_val != 321);
 	CHECK_FAIL(skel->bss->in_val != 321);
 	CHECK_FAIL(skel->bss->out_val != 321);
 	CHECK_FAIL(map_data->val[0] != 111);
 	CHECK_FAIL(map_data->val[1] != 222);
 	CHECK_FAIL(map_data->val[2] != 321);
 	CHECK_FAIL(map_data->val[far] != 3 * 321);

 	munmap(tmp2, 4 * page_size);

 	/* map all 4 pages, but with pg_off=1 page, should fail */
 	tmp1 = mmap(NULL, 4 * page_size, PROT_READ, MAP_SHARED | MAP_FIXED,
 		    data_map_fd, page_size /* initial page shift */);
 	if (CHECK(tmp1 != MAP_FAILED, "adv_mmap7", "unexpected success")) {
 		munmap(tmp1, 4 * page_size);
 		goto cleanup;
 	}

 	tmp1 = mmap(NULL, map_sz, PROT_READ, MAP_SHARED, data_map_fd, 0);
 	if (CHECK(tmp1 == MAP_FAILED, "last_mmap", "failed %d\n", errno))
 		goto cleanup;

 	test_mmap__destroy(skel);
 	skel = NULL;
 	CHECK_FAIL(munmap(bss_mmaped, bss_sz));
 	bss_mmaped = NULL;
 	CHECK_FAIL(munmap(map_mmaped, map_sz));
 	map_mmaped = NULL;

 	/* map should be still held by active mmap */
 	tmp_fd = bpf_map_get_fd_by_id(data_map_id);
 	if (CHECK(tmp_fd < 0, "get_map_by_id", "failed %d\n", errno)) {
 		munmap(tmp1, map_sz);
 		goto cleanup;
 	}
 	close(tmp_fd);

 	/* this should release data map finally */
 	munmap(tmp1, map_sz);

 	/* we need to wait for RCU grace period */
 	for (i = 0; i < 10000; i++) {
 		__u32 id = data_map_id - 1;
 		if (bpf_map_get_next_id(id, &id) || id > data_map_id)
 			break;
 		usleep(1);
 	}

 	/* should fail to get map FD by non-existing ID */
 	tmp_fd = bpf_map_get_fd_by_id(data_map_id);
 	if (CHECK(tmp_fd >= 0, "get_map_by_id_after",
 		  "unexpectedly succeeded %d\n", tmp_fd)) {
 		close(tmp_fd);
 		goto cleanup;
 	}

 cleanup:
 	if (bss_mmaped)
 		CHECK_FAIL(munmap(bss_mmaped, bss_sz));
 	if (map_mmaped)
 		CHECK_FAIL(munmap(map_mmaped, map_sz));
 	test_mmap__destroy(skel);
 }
	// SPDX-License-Identifier: GPL-2.0
	#include <test_progs.h>
	#include <sys/mman.h>
	#include "test_mmap.skel.h"

	struct map_data {
	__u64 val[512 * 4];
	};

	static size_t roundup_page(size_t sz)
	{
	long page_size = sysconf(_SC_PAGE_SIZE);
	return (sz + page_size - 1) / page_size * page_size;
	}

	void test_mmap(void)
	{
	const size_t bss_sz = roundup_page(sizeof(struct test_mmap__bss));
	const size_t map_sz = roundup_page(sizeof(struct map_data));
	const int zero = 0, one = 1, two = 2, far = 1500;
	const long page_size = sysconf(_SC_PAGE_SIZE);
	int err, duration = 0, i, data_map_fd, data_map_id, tmp_fd, rdmap_fd;
	struct bpf_map data_map, bss_map;
	void bss_mmaped = NULL, map_mmaped = NULL, tmp0, tmp1, *tmp2;
	struct test_mmap__bss *bss_data;
	struct bpf_map_info map_info;
	__u32 map_info_sz = sizeof(map_info);
	struct map_data *map_data;
	struct test_mmap *skel;
	__u64 val = 0;

	skel = test_mmap__open_and_load();
	if (CHECK(!skel, "skel_open_and_load", "skeleton open/load failed\n"))
	return;

	bss_map = skel->maps.bss;
	data_map = skel->maps.data_map;
	data_map_fd = bpf_map__fd(data_map);

	rdmap_fd = bpf_map__fd(skel->maps.rdonly_map);
	tmp1 = mmap(NULL, 4096, PROT_READ \| PROT_WRITE, MAP_SHARED, rdmap_fd, 0);
	if (CHECK(tmp1 != MAP_FAILED, "rdonly_write_mmap", "unexpected success\n")) {
	munmap(tmp1, 4096);
	goto cleanup;
	}
	/* now double-check if it's mmap()'able at all */
	tmp1 = mmap(NULL, 4096, PROT_READ, MAP_SHARED, rdmap_fd, 0);
	if (CHECK(tmp1 == MAP_FAILED, "rdonly_read_mmap", "failed: %d\n", errno))
	goto cleanup;

	/* get map's ID */
	memset(&map_info, 0, map_info_sz);
	err = bpf_obj_get_info_by_fd(data_map_fd, &map_info, &map_info_sz);
	if (CHECK(err, "map_get_info", "failed %d\n", errno))
	goto cleanup;
	data_map_id = map_info.id;

	/* mmap BSS map */
	bss_mmaped = mmap(NULL, bss_sz, PROT_READ \| PROT_WRITE, MAP_SHARED,
	bpf_map__fd(bss_map), 0);
	if (CHECK(bss_mmaped == MAP_FAILED, "bss_mmap",
	".bss mmap failed: %d\n", errno)) {
	bss_mmaped = NULL;
	goto cleanup;
	}
	/* map as R/W first */
	map_mmaped = mmap(NULL, map_sz, PROT_READ \| PROT_WRITE, MAP_SHARED,
	data_map_fd, 0);
	if (CHECK(map_mmaped == MAP_FAILED, "data_mmap",
	"data_map mmap failed: %d\n", errno)) {
	map_mmaped = NULL;
	goto cleanup;
	}

	bss_data = bss_mmaped;
	map_data = map_mmaped;

	CHECK_FAIL(bss_data->in_val);
	CHECK_FAIL(bss_data->out_val);
	CHECK_FAIL(skel->bss->in_val);
	CHECK_FAIL(skel->bss->out_val);
	CHECK_FAIL(map_data->val[0]);
	CHECK_FAIL(map_data->val[1]);
	CHECK_FAIL(map_data->val[2]);
	CHECK_FAIL(map_data->val[far]);

	err = test_mmap__attach(skel);
	if (CHECK(err, "attach_raw_tp", "err %d\n", err))
	goto cleanup;

	bss_data->in_val = 123;
	val = 111;
	CHECK_FAIL(bpf_map_update_elem(data_map_fd, &zero, &val, 0));

	usleep(1);

	CHECK_FAIL(bss_data->in_val != 123);
	CHECK_FAIL(bss_data->out_val != 123);
	CHECK_FAIL(skel->bss->in_val != 123);
	CHECK_FAIL(skel->bss->out_val != 123);
	CHECK_FAIL(map_data->val[0] != 111);
	CHECK_FAIL(map_data->val[1] != 222);
	CHECK_FAIL(map_data->val[2] != 123);
	CHECK_FAIL(map_data->val[far] != 3 * 123);

	CHECK_FAIL(bpf_map_lookup_elem(data_map_fd, &zero, &val));
	CHECK_FAIL(val != 111);
	CHECK_FAIL(bpf_map_lookup_elem(data_map_fd, &one, &val));
	CHECK_FAIL(val != 222);
	CHECK_FAIL(bpf_map_lookup_elem(data_map_fd, &two, &val));
	CHECK_FAIL(val != 123);
	CHECK_FAIL(bpf_map_lookup_elem(data_map_fd, &far, &val));
	CHECK_FAIL(val != 3 * 123);

	/* data_map freeze should fail due to R/W mmap() */
	err = bpf_map_freeze(data_map_fd);
	if (CHECK(!err \|\| errno != EBUSY, "no_freeze",
	"data_map freeze succeeded: err=%d, errno=%d\n", err, errno))
	goto cleanup;

	err = mprotect(map_mmaped, map_sz, PROT_READ);
	if (CHECK(err, "mprotect_ro", "mprotect to r/o failed %d\n", errno))
	goto cleanup;

	/* unmap R/W mapping */
	err = munmap(map_mmaped, map_sz);
	map_mmaped = NULL;
	if (CHECK(err, "data_map_munmap", "data_map munmap failed: %d\n", errno))
	goto cleanup;

	/* re-map as R/O now */
	map_mmaped = mmap(NULL, map_sz, PROT_READ, MAP_SHARED, data_map_fd, 0);
	if (CHECK(map_mmaped == MAP_FAILED, "data_mmap",
	"data_map R/O mmap failed: %d\n", errno)) {
	map_mmaped = NULL;
	goto cleanup;
	}
	err = mprotect(map_mmaped, map_sz, PROT_WRITE);
	if (CHECK(!err, "mprotect_wr", "mprotect() succeeded unexpectedly!\n"))
	goto cleanup;
	err = mprotect(map_mmaped, map_sz, PROT_EXEC);
	if (CHECK(!err, "mprotect_ex", "mprotect() succeeded unexpectedly!\n"))
	goto cleanup;
	map_data = map_mmaped;

	/* map/unmap in a loop to test ref counting */
	for (i = 0; i < 10; i++) {
	int flags = i % 2 ? PROT_READ : PROT_WRITE;
	void *p;

	p = mmap(NULL, map_sz, flags, MAP_SHARED, data_map_fd, 0);
	if (CHECK_FAIL(p == MAP_FAILED))
	goto cleanup;
	err = munmap(p, map_sz);
	if (CHECK_FAIL(err))
	goto cleanup;
	}

	/* data_map freeze should now succeed due to no R/W mapping */
	err = bpf_map_freeze(data_map_fd);
	if (CHECK(err, "freeze", "data_map freeze failed: err=%d, errno=%d\n",
	err, errno))
	goto cleanup;

	/* mapping as R/W now should fail */
	tmp1 = mmap(NULL, map_sz, PROT_READ \| PROT_WRITE, MAP_SHARED,
	data_map_fd, 0);
	if (CHECK(tmp1 != MAP_FAILED, "data_mmap", "mmap succeeded\n")) {
	munmap(tmp1, map_sz);
	goto cleanup;
	}

	bss_data->in_val = 321;
	usleep(1);
	CHECK_FAIL(bss_data->in_val != 321);
	CHECK_FAIL(bss_data->out_val != 321);
	CHECK_FAIL(skel->bss->in_val != 321);
	CHECK_FAIL(skel->bss->out_val != 321);
	CHECK_FAIL(map_data->val[0] != 111);
	CHECK_FAIL(map_data->val[1] != 222);
	CHECK_FAIL(map_data->val[2] != 321);
	CHECK_FAIL(map_data->val[far] != 3 * 321);

	/* check some more advanced mmap() manipulations */

	tmp0 = mmap(NULL, 4 * page_size, PROT_READ, MAP_SHARED \| MAP_ANONYMOUS,
	-1, 0);
	if (CHECK(tmp0 == MAP_FAILED, "adv_mmap0", "errno %d\n", errno))
	goto cleanup;

	/* map all but last page: pages 1-3 mapped */
	tmp1 = mmap(tmp0, 3 * page_size, PROT_READ, MAP_SHARED \| MAP_FIXED,
	data_map_fd, 0);
	if (CHECK(tmp0 != tmp1, "adv_mmap1", "tmp0: %p, tmp1: %p\n", tmp0, tmp1)) {
	munmap(tmp0, 4 * page_size);
	goto cleanup;
	}

	/* unmap second page: pages 1, 3 mapped */
	err = munmap(tmp1 + page_size, page_size);
	if (CHECK(err, "adv_mmap2", "errno %d\n", errno)) {
	munmap(tmp1, 4 * page_size);
	goto cleanup;
	}

	/* map page 2 back */
	tmp2 = mmap(tmp1 + page_size, page_size, PROT_READ,
	MAP_SHARED \| MAP_FIXED, data_map_fd, 0);
	if (CHECK(tmp2 == MAP_FAILED, "adv_mmap3", "errno %d\n", errno)) {
	munmap(tmp1, page_size);
	munmap(tmp1 + 2page_size, 2 page_size);
	goto cleanup;
	}
	CHECK(tmp1 + page_size != tmp2, "adv_mmap4",
	"tmp1: %p, tmp2: %p\n", tmp1, tmp2);

	/* re-map all 4 pages */
	tmp2 = mmap(tmp1, 4 * page_size, PROT_READ, MAP_SHARED \| MAP_FIXED,
	data_map_fd, 0);
	if (CHECK(tmp2 == MAP_FAILED, "adv_mmap5", "errno %d\n", errno)) {
	munmap(tmp1, 4 * page_size); /* unmap page 1 */
	goto cleanup;
	}
	CHECK(tmp1 != tmp2, "adv_mmap6", "tmp1: %p, tmp2: %p\n", tmp1, tmp2);

	map_data = tmp2;
	CHECK_FAIL(bss_data->in_val != 321);
	CHECK_FAIL(bss_data->out_val != 321);
	CHECK_FAIL(skel->bss->in_val != 321);
	CHECK_FAIL(skel->bss->out_val != 321);
	CHECK_FAIL(map_data->val[0] != 111);
	CHECK_FAIL(map_data->val[1] != 222);
	CHECK_FAIL(map_data->val[2] != 321);
	CHECK_FAIL(map_data->val[far] != 3 * 321);

	munmap(tmp2, 4 * page_size);

	/* map all 4 pages, but with pg_off=1 page, should fail */
	tmp1 = mmap(NULL, 4 * page_size, PROT_READ, MAP_SHARED \| MAP_FIXED,
	data_map_fd, page_size /* initial page shift */);
	if (CHECK(tmp1 != MAP_FAILED, "adv_mmap7", "unexpected success")) {
	munmap(tmp1, 4 * page_size);
	goto cleanup;
	}

	tmp1 = mmap(NULL, map_sz, PROT_READ, MAP_SHARED, data_map_fd, 0);
	if (CHECK(tmp1 == MAP_FAILED, "last_mmap", "failed %d\n", errno))
	goto cleanup;

	test_mmap__destroy(skel);
	skel = NULL;
	CHECK_FAIL(munmap(bss_mmaped, bss_sz));
	bss_mmaped = NULL;
	CHECK_FAIL(munmap(map_mmaped, map_sz));
	map_mmaped = NULL;

	/* map should be still held by active mmap */
	tmp_fd = bpf_map_get_fd_by_id(data_map_id);
	if (CHECK(tmp_fd < 0, "get_map_by_id", "failed %d\n", errno)) {
	munmap(tmp1, map_sz);
	goto cleanup;
	}
	close(tmp_fd);

	/* this should release data map finally */
	munmap(tmp1, map_sz);

	/* we need to wait for RCU grace period */
	for (i = 0; i < 10000; i++) {
	__u32 id = data_map_id - 1;
	if (bpf_map_get_next_id(id, &id) \|\| id > data_map_id)
	break;
	usleep(1);
	}

	/* should fail to get map FD by non-existing ID */
	tmp_fd = bpf_map_get_fd_by_id(data_map_id);
	if (CHECK(tmp_fd >= 0, "get_map_by_id_after",
	"unexpectedly succeeded %d\n", tmp_fd)) {
	close(tmp_fd);
	goto cleanup;
	}

	cleanup:
	if (bss_mmaped)
	CHECK_FAIL(munmap(bss_mmaped, bss_sz));
	if (map_mmaped)
	CHECK_FAIL(munmap(map_mmaped, map_sz));
	test_mmap__destroy(skel);
	}