v4.19.13 snapshot.
diff --git a/tools/testing/selftests/proc/.gitignore b/tools/testing/selftests/proc/.gitignore
new file mode 100644
index 0000000..82121a8
--- /dev/null
+++ b/tools/testing/selftests/proc/.gitignore
@@ -0,0 +1,13 @@
+/fd-001-lookup
+/fd-002-posix-eq
+/fd-003-kthread
+/proc-loadavg-001
+/proc-self-map-files-001
+/proc-self-map-files-002
+/proc-self-syscall
+/proc-self-wchan
+/proc-uptime-001
+/proc-uptime-002
+/read
+/self
+/thread-self
diff --git a/tools/testing/selftests/proc/Makefile b/tools/testing/selftests/proc/Makefile
new file mode 100644
index 0000000..1c12c34
--- /dev/null
+++ b/tools/testing/selftests/proc/Makefile
@@ -0,0 +1,19 @@
+CFLAGS += -Wall -O2 -Wno-unused-function
+CFLAGS += -D_GNU_SOURCE
+
+TEST_GEN_PROGS :=
+TEST_GEN_PROGS += fd-001-lookup
+TEST_GEN_PROGS += fd-002-posix-eq
+TEST_GEN_PROGS += fd-003-kthread
+TEST_GEN_PROGS += proc-loadavg-001
+TEST_GEN_PROGS += proc-self-map-files-001
+TEST_GEN_PROGS += proc-self-map-files-002
+TEST_GEN_PROGS += proc-self-syscall
+TEST_GEN_PROGS += proc-self-wchan
+TEST_GEN_PROGS += proc-uptime-001
+TEST_GEN_PROGS += proc-uptime-002
+TEST_GEN_PROGS += read
+TEST_GEN_PROGS += self
+TEST_GEN_PROGS += thread-self
+
+include ../lib.mk
diff --git a/tools/testing/selftests/proc/config b/tools/testing/selftests/proc/config
new file mode 100644
index 0000000..68fbd2b
--- /dev/null
+++ b/tools/testing/selftests/proc/config
@@ -0,0 +1 @@
+CONFIG_PROC_FS=y
diff --git a/tools/testing/selftests/proc/fd-001-lookup.c b/tools/testing/selftests/proc/fd-001-lookup.c
new file mode 100644
index 0000000..a2010df
--- /dev/null
+++ b/tools/testing/selftests/proc/fd-001-lookup.c
@@ -0,0 +1,168 @@
+/*
+ * Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+// Test /proc/*/fd lookup.
+#define _GNU_SOURCE
+#undef NDEBUG
+#include <assert.h>
+#include <dirent.h>
+#include <errno.h>
+#include <limits.h>
+#include <sched.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#include "proc.h"
+
+/* lstat(2) has more "coverage" in case non-symlink pops up somehow. */
+static void test_lookup_pass(const char *pathname)
+{
+ struct stat st;
+ ssize_t rv;
+
+ memset(&st, 0, sizeof(struct stat));
+ rv = lstat(pathname, &st);
+ assert(rv == 0);
+ assert(S_ISLNK(st.st_mode));
+}
+
+static void test_lookup_fail(const char *pathname)
+{
+ struct stat st;
+ ssize_t rv;
+
+ rv = lstat(pathname, &st);
+ assert(rv == -1 && errno == ENOENT);
+}
+
+static void test_lookup(unsigned int fd)
+{
+ char buf[64];
+ unsigned int c;
+ unsigned int u;
+ int i;
+
+ snprintf(buf, sizeof(buf), "/proc/self/fd/%u", fd);
+ test_lookup_pass(buf);
+
+ /* leading junk */
+ for (c = 1; c <= 255; c++) {
+ if (c == '/')
+ continue;
+ snprintf(buf, sizeof(buf), "/proc/self/fd/%c%u", c, fd);
+ test_lookup_fail(buf);
+ }
+
+ /* trailing junk */
+ for (c = 1; c <= 255; c++) {
+ if (c == '/')
+ continue;
+ snprintf(buf, sizeof(buf), "/proc/self/fd/%u%c", fd, c);
+ test_lookup_fail(buf);
+ }
+
+ for (i = INT_MIN; i < INT_MIN + 1024; i++) {
+ snprintf(buf, sizeof(buf), "/proc/self/fd/%d", i);
+ test_lookup_fail(buf);
+ }
+ for (i = -1024; i < 0; i++) {
+ snprintf(buf, sizeof(buf), "/proc/self/fd/%d", i);
+ test_lookup_fail(buf);
+ }
+ for (u = INT_MAX - 1024; u <= (unsigned int)INT_MAX + 1024; u++) {
+ snprintf(buf, sizeof(buf), "/proc/self/fd/%u", u);
+ test_lookup_fail(buf);
+ }
+ for (u = UINT_MAX - 1024; u != 0; u++) {
+ snprintf(buf, sizeof(buf), "/proc/self/fd/%u", u);
+ test_lookup_fail(buf);
+ }
+
+
+}
+
+int main(void)
+{
+ struct dirent *de;
+ unsigned int fd, target_fd;
+
+ if (unshare(CLONE_FILES) == -1)
+ return 1;
+
+ /* Wipe fdtable. */
+ do {
+ DIR *d;
+
+ d = opendir("/proc/self/fd");
+ if (!d)
+ return 1;
+
+ de = xreaddir(d);
+ assert(de->d_type == DT_DIR);
+ assert(streq(de->d_name, "."));
+
+ de = xreaddir(d);
+ assert(de->d_type == DT_DIR);
+ assert(streq(de->d_name, ".."));
+next:
+ de = xreaddir(d);
+ if (de) {
+ unsigned long long fd_ull;
+ unsigned int fd;
+ char *end;
+
+ assert(de->d_type == DT_LNK);
+
+ fd_ull = xstrtoull(de->d_name, &end);
+ assert(*end == '\0');
+ assert(fd_ull == (unsigned int)fd_ull);
+
+ fd = fd_ull;
+ if (fd == dirfd(d))
+ goto next;
+ close(fd);
+ }
+
+ closedir(d);
+ } while (de);
+
+ /* Now fdtable is clean. */
+
+ fd = open("/", O_PATH|O_DIRECTORY);
+ assert(fd == 0);
+ test_lookup(fd);
+ close(fd);
+
+ /* Clean again! */
+
+ fd = open("/", O_PATH|O_DIRECTORY);
+ assert(fd == 0);
+ /* Default RLIMIT_NOFILE-1 */
+ target_fd = 1023;
+ while (target_fd > 0) {
+ if (dup2(fd, target_fd) == target_fd)
+ break;
+ target_fd /= 2;
+ }
+ assert(target_fd > 0);
+ close(fd);
+ test_lookup(target_fd);
+ close(target_fd);
+
+ return 0;
+}
diff --git a/tools/testing/selftests/proc/fd-002-posix-eq.c b/tools/testing/selftests/proc/fd-002-posix-eq.c
new file mode 100644
index 0000000..417322c
--- /dev/null
+++ b/tools/testing/selftests/proc/fd-002-posix-eq.c
@@ -0,0 +1,57 @@
+/*
+ * Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+// Test that open(/proc/*/fd/*) opens the same file.
+#undef NDEBUG
+#include <assert.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+int main(void)
+{
+ int fd0, fd1, fd2;
+ struct stat st0, st1, st2;
+ char buf[64];
+ int rv;
+
+ fd0 = open("/", O_DIRECTORY|O_RDONLY);
+ assert(fd0 >= 0);
+
+ snprintf(buf, sizeof(buf), "/proc/self/fd/%u", fd0);
+ fd1 = open(buf, O_RDONLY);
+ assert(fd1 >= 0);
+
+ snprintf(buf, sizeof(buf), "/proc/thread-self/fd/%u", fd0);
+ fd2 = open(buf, O_RDONLY);
+ assert(fd2 >= 0);
+
+ rv = fstat(fd0, &st0);
+ assert(rv == 0);
+ rv = fstat(fd1, &st1);
+ assert(rv == 0);
+ rv = fstat(fd2, &st2);
+ assert(rv == 0);
+
+ assert(st0.st_dev == st1.st_dev);
+ assert(st0.st_ino == st1.st_ino);
+
+ assert(st0.st_dev == st2.st_dev);
+ assert(st0.st_ino == st2.st_ino);
+
+ return 0;
+}
diff --git a/tools/testing/selftests/proc/fd-003-kthread.c b/tools/testing/selftests/proc/fd-003-kthread.c
new file mode 100644
index 0000000..1d659d5
--- /dev/null
+++ b/tools/testing/selftests/proc/fd-003-kthread.c
@@ -0,0 +1,178 @@
+/*
+ * Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+// Test that /proc/$KERNEL_THREAD/fd/ is empty.
+#define _GNU_SOURCE
+#undef NDEBUG
+#include <sys/syscall.h>
+#include <assert.h>
+#include <dirent.h>
+#include <limits.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#include "proc.h"
+
+#define PF_KHTREAD 0x00200000
+
+/*
+ * Test for kernel threadness atomically with openat().
+ *
+ * Return /proc/$PID/fd descriptor if process is kernel thread.
+ * Return -1 if a process is userspace process.
+ */
+static int kernel_thread_fd(unsigned int pid)
+{
+ unsigned int flags = 0;
+ char buf[4096];
+ int dir_fd, fd;
+ ssize_t rv;
+
+ snprintf(buf, sizeof(buf), "/proc/%u", pid);
+ dir_fd = open(buf, O_RDONLY|O_DIRECTORY);
+ if (dir_fd == -1)
+ return -1;
+
+ /*
+ * Believe it or not, struct task_struct::flags is directly exposed
+ * to userspace!
+ */
+ fd = openat(dir_fd, "stat", O_RDONLY);
+ if (fd == -1) {
+ close(dir_fd);
+ return -1;
+ }
+ rv = read(fd, buf, sizeof(buf));
+ close(fd);
+ if (0 < rv && rv <= sizeof(buf)) {
+ unsigned long long flags_ull;
+ char *p, *end;
+ int i;
+
+ assert(buf[rv - 1] == '\n');
+ buf[rv - 1] = '\0';
+
+ /* Search backwards: ->comm can contain whitespace and ')'. */
+ for (i = 0; i < 43; i++) {
+ p = strrchr(buf, ' ');
+ assert(p);
+ *p = '\0';
+ }
+
+ p = strrchr(buf, ' ');
+ assert(p);
+
+ flags_ull = xstrtoull(p + 1, &end);
+ assert(*end == '\0');
+ assert(flags_ull == (unsigned int)flags_ull);
+
+ flags = flags_ull;
+ }
+
+ fd = -1;
+ if (flags & PF_KHTREAD) {
+ fd = openat(dir_fd, "fd", O_RDONLY|O_DIRECTORY);
+ }
+ close(dir_fd);
+ return fd;
+}
+
+static void test_readdir(int fd)
+{
+ DIR *d;
+ struct dirent *de;
+
+ d = fdopendir(fd);
+ assert(d);
+
+ de = xreaddir(d);
+ assert(streq(de->d_name, "."));
+ assert(de->d_type == DT_DIR);
+
+ de = xreaddir(d);
+ assert(streq(de->d_name, ".."));
+ assert(de->d_type == DT_DIR);
+
+ de = xreaddir(d);
+ assert(!de);
+}
+
+static inline int sys_statx(int dirfd, const char *pathname, int flags,
+ unsigned int mask, void *stx)
+{
+ return syscall(SYS_statx, dirfd, pathname, flags, mask, stx);
+}
+
+static void test_lookup_fail(int fd, const char *pathname)
+{
+ char stx[256] __attribute__((aligned(8)));
+ int rv;
+
+ rv = sys_statx(fd, pathname, AT_SYMLINK_NOFOLLOW, 0, (void *)stx);
+ assert(rv == -1 && errno == ENOENT);
+}
+
+static void test_lookup(int fd)
+{
+ char buf[64];
+ unsigned int u;
+ int i;
+
+ for (i = INT_MIN; i < INT_MIN + 1024; i++) {
+ snprintf(buf, sizeof(buf), "%d", i);
+ test_lookup_fail(fd, buf);
+ }
+ for (i = -1024; i < 1024; i++) {
+ snprintf(buf, sizeof(buf), "%d", i);
+ test_lookup_fail(fd, buf);
+ }
+ for (u = INT_MAX - 1024; u < (unsigned int)INT_MAX + 1024; u++) {
+ snprintf(buf, sizeof(buf), "%u", u);
+ test_lookup_fail(fd, buf);
+ }
+ for (u = UINT_MAX - 1024; u != 0; u++) {
+ snprintf(buf, sizeof(buf), "%u", u);
+ test_lookup_fail(fd, buf);
+ }
+}
+
+int main(void)
+{
+ unsigned int pid;
+ int fd;
+
+ /*
+ * In theory this will loop indefinitely if kernel threads are exiled
+ * from /proc.
+ *
+ * Start with kthreadd.
+ */
+ pid = 2;
+ while ((fd = kernel_thread_fd(pid)) == -1 && pid < 1024) {
+ pid++;
+ }
+ /* EACCES if run as non-root. */
+ if (pid >= 1024)
+ return 1;
+
+ test_readdir(fd);
+ test_lookup(fd);
+
+ return 0;
+}
diff --git a/tools/testing/selftests/proc/proc-loadavg-001.c b/tools/testing/selftests/proc/proc-loadavg-001.c
new file mode 100644
index 0000000..fcff704
--- /dev/null
+++ b/tools/testing/selftests/proc/proc-loadavg-001.c
@@ -0,0 +1,83 @@
+/*
+ * Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+/* Test that /proc/loadavg correctly reports last pid in pid namespace. */
+#define _GNU_SOURCE
+#include <errno.h>
+#include <sched.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/wait.h>
+
+int main(void)
+{
+ pid_t pid;
+ int wstatus;
+
+ if (unshare(CLONE_NEWPID) == -1) {
+ if (errno == ENOSYS || errno == EPERM)
+ return 2;
+ return 1;
+ }
+
+ pid = fork();
+ if (pid == -1)
+ return 1;
+ if (pid == 0) {
+ char buf[128], *p;
+ int fd;
+ ssize_t rv;
+
+ fd = open("/proc/loadavg" , O_RDONLY);
+ if (fd == -1)
+ return 1;
+ rv = read(fd, buf, sizeof(buf));
+ if (rv < 3)
+ return 1;
+ p = buf + rv;
+
+ /* pid 1 */
+ if (!(p[-3] == ' ' && p[-2] == '1' && p[-1] == '\n'))
+ return 1;
+
+ pid = fork();
+ if (pid == -1)
+ return 1;
+ if (pid == 0)
+ return 0;
+ if (waitpid(pid, NULL, 0) == -1)
+ return 1;
+
+ lseek(fd, 0, SEEK_SET);
+ rv = read(fd, buf, sizeof(buf));
+ if (rv < 3)
+ return 1;
+ p = buf + rv;
+
+ /* pid 2 */
+ if (!(p[-3] == ' ' && p[-2] == '2' && p[-1] == '\n'))
+ return 1;
+
+ return 0;
+ }
+
+ if (waitpid(pid, &wstatus, 0) == -1)
+ return 1;
+ if (WIFEXITED(wstatus) && WEXITSTATUS(wstatus) == 0)
+ return 0;
+ return 1;
+}
diff --git a/tools/testing/selftests/proc/proc-self-map-files-001.c b/tools/testing/selftests/proc/proc-self-map-files-001.c
new file mode 100644
index 0000000..4209c64
--- /dev/null
+++ b/tools/testing/selftests/proc/proc-self-map-files-001.c
@@ -0,0 +1,82 @@
+/*
+ * Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+/* Test readlink /proc/self/map_files/... */
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <stdlib.h>
+
+static void pass(const char *fmt, unsigned long a, unsigned long b)
+{
+ char name[64];
+ char buf[64];
+
+ snprintf(name, sizeof(name), fmt, a, b);
+ if (readlink(name, buf, sizeof(buf)) == -1)
+ exit(1);
+}
+
+static void fail(const char *fmt, unsigned long a, unsigned long b)
+{
+ char name[64];
+ char buf[64];
+
+ snprintf(name, sizeof(name), fmt, a, b);
+ if (readlink(name, buf, sizeof(buf)) == -1 && errno == ENOENT)
+ return;
+ exit(1);
+}
+
+int main(void)
+{
+ const unsigned int PAGE_SIZE = sysconf(_SC_PAGESIZE);
+ void *p;
+ int fd;
+ unsigned long a, b;
+
+ fd = open("/dev/zero", O_RDONLY);
+ if (fd == -1)
+ return 1;
+
+ p = mmap(NULL, PAGE_SIZE, PROT_NONE, MAP_PRIVATE|MAP_FILE, fd, 0);
+ if (p == MAP_FAILED)
+ return 1;
+
+ a = (unsigned long)p;
+ b = (unsigned long)p + PAGE_SIZE;
+
+ pass("/proc/self/map_files/%lx-%lx", a, b);
+ fail("/proc/self/map_files/ %lx-%lx", a, b);
+ fail("/proc/self/map_files/%lx -%lx", a, b);
+ fail("/proc/self/map_files/%lx- %lx", a, b);
+ fail("/proc/self/map_files/%lx-%lx ", a, b);
+ fail("/proc/self/map_files/0%lx-%lx", a, b);
+ fail("/proc/self/map_files/%lx-0%lx", a, b);
+ if (sizeof(long) == 4) {
+ fail("/proc/self/map_files/100000000%lx-%lx", a, b);
+ fail("/proc/self/map_files/%lx-100000000%lx", a, b);
+ } else if (sizeof(long) == 8) {
+ fail("/proc/self/map_files/10000000000000000%lx-%lx", a, b);
+ fail("/proc/self/map_files/%lx-10000000000000000%lx", a, b);
+ } else
+ return 1;
+
+ return 0;
+}
diff --git a/tools/testing/selftests/proc/proc-self-map-files-002.c b/tools/testing/selftests/proc/proc-self-map-files-002.c
new file mode 100644
index 0000000..8574442
--- /dev/null
+++ b/tools/testing/selftests/proc/proc-self-map-files-002.c
@@ -0,0 +1,90 @@
+/*
+ * Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+/* Test readlink /proc/self/map_files/... with minimum address. */
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <stdlib.h>
+
+static void pass(const char *fmt, unsigned long a, unsigned long b)
+{
+ char name[64];
+ char buf[64];
+
+ snprintf(name, sizeof(name), fmt, a, b);
+ if (readlink(name, buf, sizeof(buf)) == -1)
+ exit(1);
+}
+
+static void fail(const char *fmt, unsigned long a, unsigned long b)
+{
+ char name[64];
+ char buf[64];
+
+ snprintf(name, sizeof(name), fmt, a, b);
+ if (readlink(name, buf, sizeof(buf)) == -1 && errno == ENOENT)
+ return;
+ exit(1);
+}
+
+int main(void)
+{
+ const unsigned int PAGE_SIZE = sysconf(_SC_PAGESIZE);
+#ifdef __arm__
+ unsigned long va = 2 * PAGE_SIZE;
+#else
+ unsigned long va = 0;
+#endif
+ void *p;
+ int fd;
+ unsigned long a, b;
+
+ fd = open("/dev/zero", O_RDONLY);
+ if (fd == -1)
+ return 1;
+
+ p = mmap((void *)va, PAGE_SIZE, PROT_NONE, MAP_PRIVATE|MAP_FILE|MAP_FIXED, fd, 0);
+ if (p == MAP_FAILED) {
+ if (errno == EPERM)
+ return 2;
+ return 1;
+ }
+
+ a = (unsigned long)p;
+ b = (unsigned long)p + PAGE_SIZE;
+
+ pass("/proc/self/map_files/%lx-%lx", a, b);
+ fail("/proc/self/map_files/ %lx-%lx", a, b);
+ fail("/proc/self/map_files/%lx -%lx", a, b);
+ fail("/proc/self/map_files/%lx- %lx", a, b);
+ fail("/proc/self/map_files/%lx-%lx ", a, b);
+ fail("/proc/self/map_files/0%lx-%lx", a, b);
+ fail("/proc/self/map_files/%lx-0%lx", a, b);
+ if (sizeof(long) == 4) {
+ fail("/proc/self/map_files/100000000%lx-%lx", a, b);
+ fail("/proc/self/map_files/%lx-100000000%lx", a, b);
+ } else if (sizeof(long) == 8) {
+ fail("/proc/self/map_files/10000000000000000%lx-%lx", a, b);
+ fail("/proc/self/map_files/%lx-10000000000000000%lx", a, b);
+ } else
+ return 1;
+
+ return 0;
+}
diff --git a/tools/testing/selftests/proc/proc-self-syscall.c b/tools/testing/selftests/proc/proc-self-syscall.c
new file mode 100644
index 0000000..5ab5f48
--- /dev/null
+++ b/tools/testing/selftests/proc/proc-self-syscall.c
@@ -0,0 +1,60 @@
+/*
+ * Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+#define _GNU_SOURCE
+#include <unistd.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdio.h>
+
+static inline ssize_t sys_read(int fd, void *buf, size_t len)
+{
+ return syscall(SYS_read, fd, buf, len);
+}
+
+int main(void)
+{
+ char buf1[64];
+ char buf2[64];
+ int fd;
+ ssize_t rv;
+
+ fd = open("/proc/self/syscall", O_RDONLY);
+ if (fd == -1) {
+ if (errno == ENOENT)
+ return 2;
+ return 1;
+ }
+
+ /* Do direct system call as libc can wrap anything. */
+ snprintf(buf1, sizeof(buf1), "%ld 0x%lx 0x%lx 0x%lx",
+ (long)SYS_read, (long)fd, (long)buf2, (long)sizeof(buf2));
+
+ memset(buf2, 0, sizeof(buf2));
+ rv = sys_read(fd, buf2, sizeof(buf2));
+ if (rv < 0)
+ return 1;
+ if (rv < strlen(buf1))
+ return 1;
+ if (strncmp(buf1, buf2, strlen(buf1)) != 0)
+ return 1;
+
+ return 0;
+}
diff --git a/tools/testing/selftests/proc/proc-self-wchan.c b/tools/testing/selftests/proc/proc-self-wchan.c
new file mode 100644
index 0000000..a38b2fb
--- /dev/null
+++ b/tools/testing/selftests/proc/proc-self-wchan.c
@@ -0,0 +1,40 @@
+/*
+ * Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <unistd.h>
+
+int main(void)
+{
+ char buf[64];
+ int fd;
+
+ fd = open("/proc/self/wchan", O_RDONLY);
+ if (fd == -1) {
+ if (errno == ENOENT)
+ return 2;
+ return 1;
+ }
+
+ buf[0] = '\0';
+ if (read(fd, buf, sizeof(buf)) != 1)
+ return 1;
+ if (buf[0] != '0')
+ return 1;
+ return 0;
+}
diff --git a/tools/testing/selftests/proc/proc-uptime-001.c b/tools/testing/selftests/proc/proc-uptime-001.c
new file mode 100644
index 0000000..781f7a5
--- /dev/null
+++ b/tools/testing/selftests/proc/proc-uptime-001.c
@@ -0,0 +1,45 @@
+/*
+ * Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+// Test that values in /proc/uptime increment monotonically.
+#undef NDEBUG
+#include <assert.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#include "proc-uptime.h"
+
+int main(void)
+{
+ uint64_t start, u0, u1, i0, i1;
+ int fd;
+
+ fd = open("/proc/uptime", O_RDONLY);
+ assert(fd >= 0);
+
+ proc_uptime(fd, &u0, &i0);
+ start = u0;
+ do {
+ proc_uptime(fd, &u1, &i1);
+ assert(u1 >= u0);
+ assert(i1 >= i0);
+ u0 = u1;
+ i0 = i1;
+ } while (u1 - start < 100);
+
+ return 0;
+}
diff --git a/tools/testing/selftests/proc/proc-uptime-002.c b/tools/testing/selftests/proc/proc-uptime-002.c
new file mode 100644
index 0000000..30e2b78
--- /dev/null
+++ b/tools/testing/selftests/proc/proc-uptime-002.c
@@ -0,0 +1,79 @@
+/*
+ * Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+// Test that values in /proc/uptime increment monotonically
+// while shifting across CPUs.
+#define _GNU_SOURCE
+#undef NDEBUG
+#include <assert.h>
+#include <unistd.h>
+#include <sys/syscall.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <stdint.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#include "proc-uptime.h"
+
+static inline int sys_sched_getaffinity(pid_t pid, unsigned int len, unsigned long *m)
+{
+ return syscall(SYS_sched_getaffinity, pid, len, m);
+}
+
+static inline int sys_sched_setaffinity(pid_t pid, unsigned int len, unsigned long *m)
+{
+ return syscall(SYS_sched_setaffinity, pid, len, m);
+}
+
+int main(void)
+{
+ unsigned int len;
+ unsigned long *m;
+ unsigned int cpu;
+ uint64_t u0, u1, i0, i1;
+ int fd;
+
+ /* find out "nr_cpu_ids" */
+ m = NULL;
+ len = 0;
+ do {
+ len += sizeof(unsigned long);
+ free(m);
+ m = malloc(len);
+ } while (sys_sched_getaffinity(0, len, m) == -EINVAL);
+
+ fd = open("/proc/uptime", O_RDONLY);
+ assert(fd >= 0);
+
+ proc_uptime(fd, &u0, &i0);
+ for (cpu = 0; cpu < len * 8; cpu++) {
+ memset(m, 0, len);
+ m[cpu / (8 * sizeof(unsigned long))] |= 1UL << (cpu % (8 * sizeof(unsigned long)));
+
+ /* CPU might not exist, ignore error */
+ sys_sched_setaffinity(0, len, m);
+
+ proc_uptime(fd, &u1, &i1);
+ assert(u1 >= u0);
+ assert(i1 >= i0);
+ u0 = u1;
+ i0 = i1;
+ }
+
+ return 0;
+}
diff --git a/tools/testing/selftests/proc/proc-uptime.h b/tools/testing/selftests/proc/proc-uptime.h
new file mode 100644
index 0000000..dc6a42b
--- /dev/null
+++ b/tools/testing/selftests/proc/proc-uptime.h
@@ -0,0 +1,60 @@
+/*
+ * Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+#undef NDEBUG
+#include <assert.h>
+#include <errno.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "proc.h"
+
+static void proc_uptime(int fd, uint64_t *uptime, uint64_t *idle)
+{
+ uint64_t val1, val2;
+ char buf[64], *p;
+ ssize_t rv;
+
+ /* save "p < end" checks */
+ memset(buf, 0, sizeof(buf));
+ rv = pread(fd, buf, sizeof(buf), 0);
+ assert(0 <= rv && rv <= sizeof(buf));
+ buf[sizeof(buf) - 1] = '\0';
+
+ p = buf;
+
+ val1 = xstrtoull(p, &p);
+ assert(p[0] == '.');
+ assert('0' <= p[1] && p[1] <= '9');
+ assert('0' <= p[2] && p[2] <= '9');
+ assert(p[3] == ' ');
+
+ val2 = (p[1] - '0') * 10 + p[2] - '0';
+ *uptime = val1 * 100 + val2;
+
+ p += 4;
+
+ val1 = xstrtoull(p, &p);
+ assert(p[0] == '.');
+ assert('0' <= p[1] && p[1] <= '9');
+ assert('0' <= p[2] && p[2] <= '9');
+ assert(p[3] == '\n');
+
+ val2 = (p[1] - '0') * 10 + p[2] - '0';
+ *idle = val1 * 100 + val2;
+
+ assert(p + 4 == buf + rv);
+}
diff --git a/tools/testing/selftests/proc/proc.h b/tools/testing/selftests/proc/proc.h
new file mode 100644
index 0000000..b7d57ea
--- /dev/null
+++ b/tools/testing/selftests/proc/proc.h
@@ -0,0 +1,51 @@
+#pragma once
+#undef NDEBUG
+#include <assert.h>
+#include <dirent.h>
+#include <errno.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/syscall.h>
+
+static inline pid_t sys_getpid(void)
+{
+ return syscall(SYS_getpid);
+}
+
+static inline pid_t sys_gettid(void)
+{
+ return syscall(SYS_gettid);
+}
+
+static inline bool streq(const char *s1, const char *s2)
+{
+ return strcmp(s1, s2) == 0;
+}
+
+static unsigned long long xstrtoull(const char *p, char **end)
+{
+ if (*p == '0') {
+ *end = (char *)p + 1;
+ return 0;
+ } else if ('1' <= *p && *p <= '9') {
+ unsigned long long val;
+
+ errno = 0;
+ val = strtoull(p, end, 10);
+ assert(errno == 0);
+ return val;
+ } else
+ assert(0);
+}
+
+static struct dirent *xreaddir(DIR *d)
+{
+ struct dirent *de;
+
+ errno = 0;
+ de = readdir(d);
+ assert(de || errno == 0);
+ return de;
+}
diff --git a/tools/testing/selftests/proc/read.c b/tools/testing/selftests/proc/read.c
new file mode 100644
index 0000000..563e752
--- /dev/null
+++ b/tools/testing/selftests/proc/read.c
@@ -0,0 +1,132 @@
+/*
+ * Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+// Test
+// 1) read of every file in /proc
+// 2) readlink of every symlink in /proc
+// 3) recursively (1) + (2) for every directory in /proc
+// 4) write to /proc/*/clear_refs and /proc/*/task/*/clear_refs
+// 5) write to /proc/sysrq-trigger
+#undef NDEBUG
+#include <assert.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <dirent.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#include "proc.h"
+
+static void f_reg(DIR *d, const char *filename)
+{
+ char buf[4096];
+ int fd;
+ ssize_t rv;
+
+ /* read from /proc/kmsg can block */
+ fd = openat(dirfd(d), filename, O_RDONLY|O_NONBLOCK);
+ if (fd == -1)
+ return;
+ rv = read(fd, buf, sizeof(buf));
+ assert((0 <= rv && rv <= sizeof(buf)) || rv == -1);
+ close(fd);
+}
+
+static void f_reg_write(DIR *d, const char *filename, const char *buf, size_t len)
+{
+ int fd;
+ ssize_t rv;
+
+ fd = openat(dirfd(d), filename, O_WRONLY);
+ if (fd == -1)
+ return;
+ rv = write(fd, buf, len);
+ assert((0 <= rv && rv <= len) || rv == -1);
+ close(fd);
+}
+
+static void f_lnk(DIR *d, const char *filename)
+{
+ char buf[4096];
+ ssize_t rv;
+
+ rv = readlinkat(dirfd(d), filename, buf, sizeof(buf));
+ assert((0 <= rv && rv <= sizeof(buf)) || rv == -1);
+}
+
+static void f(DIR *d, unsigned int level)
+{
+ struct dirent *de;
+
+ de = xreaddir(d);
+ assert(de->d_type == DT_DIR);
+ assert(streq(de->d_name, "."));
+
+ de = xreaddir(d);
+ assert(de->d_type == DT_DIR);
+ assert(streq(de->d_name, ".."));
+
+ while ((de = xreaddir(d))) {
+ assert(!streq(de->d_name, "."));
+ assert(!streq(de->d_name, ".."));
+
+ switch (de->d_type) {
+ DIR *dd;
+ int fd;
+
+ case DT_REG:
+ if (level == 0 && streq(de->d_name, "sysrq-trigger")) {
+ f_reg_write(d, de->d_name, "h", 1);
+ } else if (level == 1 && streq(de->d_name, "clear_refs")) {
+ f_reg_write(d, de->d_name, "1", 1);
+ } else if (level == 3 && streq(de->d_name, "clear_refs")) {
+ f_reg_write(d, de->d_name, "1", 1);
+ } else {
+ f_reg(d, de->d_name);
+ }
+ break;
+ case DT_DIR:
+ fd = openat(dirfd(d), de->d_name, O_DIRECTORY|O_RDONLY);
+ if (fd == -1)
+ continue;
+ dd = fdopendir(fd);
+ if (!dd)
+ continue;
+ f(dd, level + 1);
+ closedir(dd);
+ break;
+ case DT_LNK:
+ f_lnk(d, de->d_name);
+ break;
+ default:
+ assert(0);
+ }
+ }
+}
+
+int main(void)
+{
+ DIR *d;
+
+ d = opendir("/proc");
+ if (!d)
+ return 2;
+ f(d, 0);
+ return 0;
+}
diff --git a/tools/testing/selftests/proc/self.c b/tools/testing/selftests/proc/self.c
new file mode 100644
index 0000000..21c15a1
--- /dev/null
+++ b/tools/testing/selftests/proc/self.c
@@ -0,0 +1,39 @@
+/*
+ * Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+// Test that /proc/self gives correct TGID.
+#undef NDEBUG
+#include <assert.h>
+#include <stdio.h>
+#include <unistd.h>
+
+#include "proc.h"
+
+int main(void)
+{
+ char buf1[64], buf2[64];
+ pid_t pid;
+ ssize_t rv;
+
+ pid = sys_getpid();
+ snprintf(buf1, sizeof(buf1), "%u", pid);
+
+ rv = readlink("/proc/self", buf2, sizeof(buf2));
+ assert(rv == strlen(buf1));
+ buf2[rv] = '\0';
+ assert(streq(buf1, buf2));
+
+ return 0;
+}
diff --git a/tools/testing/selftests/proc/thread-self.c b/tools/testing/selftests/proc/thread-self.c
new file mode 100644
index 0000000..4b23b39
--- /dev/null
+++ b/tools/testing/selftests/proc/thread-self.c
@@ -0,0 +1,64 @@
+/*
+ * Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+// Test that /proc/thread-self gives correct TGID/PID.
+#undef NDEBUG
+#include <assert.h>
+#include <sched.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <sys/wait.h>
+
+#include "proc.h"
+
+int f(void *arg)
+{
+ char buf1[64], buf2[64];
+ pid_t pid, tid;
+ ssize_t rv;
+
+ pid = sys_getpid();
+ tid = sys_gettid();
+ snprintf(buf1, sizeof(buf1), "%u/task/%u", pid, tid);
+
+ rv = readlink("/proc/thread-self", buf2, sizeof(buf2));
+ assert(rv == strlen(buf1));
+ buf2[rv] = '\0';
+ assert(streq(buf1, buf2));
+
+ if (arg)
+ exit(0);
+ return 0;
+}
+
+int main(void)
+{
+ const int PAGE_SIZE = sysconf(_SC_PAGESIZE);
+ pid_t pid;
+ void *stack;
+
+ /* main thread */
+ f((void *)0);
+
+ stack = mmap(NULL, 2 * PAGE_SIZE, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
+ assert(stack != MAP_FAILED);
+ /* side thread */
+ pid = clone(f, stack + PAGE_SIZE, CLONE_THREAD|CLONE_SIGHAND|CLONE_VM, (void *)1);
+ assert(pid > 0);
+ pause();
+
+ return 0;
+}