X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=tests%2Fregression%2Fkernel%2Fselect_poll_epoll.cpp;fp=tests%2Fregression%2Fkernel%2Fselect_poll_epoll.cpp;h=abedc0aa929557c7aa859e76788d71d53e0f0cb4;hb=d40c26206a44d9e247bbcdc01afb34c41d0c490d;hp=0000000000000000000000000000000000000000;hpb=d61d4fae208679ab4824cb0b53cfc1390803944e;p=lttng-tools.git

diff --git a/tests/regression/kernel/select_poll_epoll.cpp b/tests/regression/kernel/select_poll_epoll.cpp
new file mode 100644
index 000000000..abedc0aa9
--- /dev/null
+++ b/tests/regression/kernel/select_poll_epoll.cpp
@@ -0,0 +1,1021 @@
+/*
+ * Copyright (C) 2016 Julien Desfossez <jdesfossez@efficios.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ *
+ */
+
+#include <stdio.h>
+#include <poll.h>
+#include <signal.h>
+#include <unistd.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stddef.h>
+#include <sys/select.h>
+#include <sys/epoll.h>
+#include <popt.h>
+#include <sys/time.h>
+#include <sys/resource.h>
+#include <limits.h>
+#include <pthread.h>
+#include <sys/mman.h>
+#include <common/compat/time.h>
+#include <common/error.h>
+
+#define BUF_SIZE 256
+#define NB_FD 1
+#define MAX_FDS 2047
+#define NR_ITER 1000 /* for stress-tests */
+
+#define MIN_NR_FDS 5 /* the minimum number of open FDs required for the test to run */
+#define BIG_SELECT_FD 1022
+
+#define MSEC_PER_USEC 1000
+#define MSEC_PER_NSEC (MSEC_PER_USEC * 1000)
+
+static int timeout; /* seconds, -1 to disable */
+static volatile int stop_thread;
+static int wait_fd;
+
+/* Used by logging utils. */
+int lttng_opt_quiet, lttng_opt_verbose, lttng_opt_mi;
+
+static void run_working_cases(FILE *validation_output_file);
+static void pselect_invalid_fd(FILE *validation_output_file);
+static void test_ppoll_big(FILE *validation_output_file);
+static void ppoll_fds_buffer_overflow(FILE *validation_output_file);
+static void pselect_invalid_pointer(FILE *validation_output_file);
+static void ppoll_fds_ulong_max(FILE *validation_output_file);
+static void epoll_pwait_invalid_pointer(FILE *validation_output_file);
+static void epoll_pwait_int_max(FILE *validation_output_file);
+static void ppoll_concurrent_write(FILE *validation_output_file);
+static void epoll_pwait_concurrent_munmap(FILE *validation_output_file);
+
+typedef void (*test_case_cb)(FILE *output_file);
+
+static const struct test_case {
+	test_case_cb run;
+	bool produces_validation_info;
+	int timeout;
+} test_cases [] =
+{
+	{ .run = run_working_cases, .produces_validation_info = true, .timeout = -1 },
+	{ .run = run_working_cases, .produces_validation_info = true, .timeout = 1 },
+	{ .run = pselect_invalid_fd, .produces_validation_info = false },
+	{ .run = test_ppoll_big, .produces_validation_info = false },
+	{ .run = ppoll_fds_buffer_overflow, .produces_validation_info = false },
+	{ .run = pselect_invalid_pointer, .produces_validation_info = false },
+	{ .run = ppoll_fds_ulong_max, .produces_validation_info = false },
+	{ .run = epoll_pwait_invalid_pointer, .produces_validation_info = true },
+	{ .run = epoll_pwait_int_max, .produces_validation_info = true },
+	{ .run = ppoll_concurrent_write, .produces_validation_info = false },
+	{ .run = epoll_pwait_concurrent_munmap, .produces_validation_info = true },
+};
+
+struct ppoll_thread_data {
+	struct pollfd *ufds;
+	int value;
+};
+
+static
+void test_select_big(void)
+{
+	fd_set rfds, wfds, exfds;
+	struct timeval tv;
+	int ret;
+	int fd2;
+	char buf[BUF_SIZE];
+
+	FD_ZERO(&rfds);
+	FD_ZERO(&wfds);
+	FD_ZERO(&exfds);
+
+	fd2 = dup2(wait_fd, BIG_SELECT_FD);
+	if (fd2 < 0) {
+		PERROR("dup2");
+		goto end;
+	}
+	FD_SET(fd2, &rfds);
+
+	tv.tv_sec = 0;
+	tv.tv_usec = timeout * MSEC_PER_USEC;
+
+	if (timeout > 0) {
+		ret = select(fd2 + 1, &rfds, &wfds, &exfds, &tv);
+	} else {
+		ret = select(fd2 + 1, &rfds, &wfds, &exfds, NULL);
+	}
+
+	if (ret == -1) {
+		PERROR("select()");
+	} else if (ret) {
+		ret = read(wait_fd, buf, BUF_SIZE);
+		if (ret < 0) {
+			PERROR("[select] read");
+		}
+	}
+
+	ret = close(BIG_SELECT_FD);
+	if (ret) {
+		PERROR("close");
+	}
+
+end:
+	return;
+}
+
+static
+void test_pselect(void)
+{
+	fd_set rfds;
+	struct timespec tv;
+	int ret;
+	char buf[BUF_SIZE];
+
+	FD_ZERO(&rfds);
+	FD_SET(wait_fd, &rfds);
+
+	tv.tv_sec = 0;
+	tv.tv_nsec = timeout * MSEC_PER_NSEC;
+
+	if (timeout > 0) {
+		ret = pselect(1, &rfds, NULL, NULL, &tv, NULL);
+	} else {
+		ret = pselect(1, &rfds, NULL, NULL, NULL, NULL);
+	}
+
+	if (ret == -1) {
+		PERROR("pselect()");
+	} else if (ret) {
+		ret = read(wait_fd, buf, BUF_SIZE);
+		if (ret < 0) {
+			PERROR("[pselect] read");
+		}
+	}
+}
+
+static
+void test_select(void)
+{
+	fd_set rfds;
+	struct timeval tv;
+	int ret;
+	char buf[BUF_SIZE];
+
+	FD_ZERO(&rfds);
+	FD_SET(wait_fd, &rfds);
+
+	tv.tv_sec = 0;
+	tv.tv_usec = timeout * MSEC_PER_USEC;
+
+	if (timeout > 0) {
+		ret = select(1, &rfds, NULL, NULL, &tv);
+	} else {
+		ret = select(1, &rfds, NULL, NULL, NULL);
+	}
+
+	if (ret == -1) {
+		PERROR("select()");
+	} else if (ret) {
+		ret = read(wait_fd, buf, BUF_SIZE);
+		if (ret < 0) {
+			PERROR("[select] read");
+		}
+	}
+}
+
+static
+void test_poll(void)
+{
+	struct pollfd ufds[NB_FD];
+	char buf[BUF_SIZE];
+	int ret;
+
+	ufds[0].fd = wait_fd;
+	ufds[0].events = POLLIN|POLLPRI;
+
+	ret = poll(ufds, 1, timeout);
+
+	if (ret < 0) {
+		PERROR("poll");
+	} else if (ret > 0) {
+		ret = read(wait_fd, buf, BUF_SIZE);
+		if (ret < 0) {
+			PERROR("[poll] read");
+		}
+	}
+}
+
+static
+void test_ppoll(void)
+{
+	struct pollfd ufds[NB_FD];
+	char buf[BUF_SIZE];
+	int ret;
+	struct timespec ts;
+
+	ufds[0].fd = wait_fd;
+	ufds[0].events = POLLIN|POLLPRI;
+
+	if (timeout > 0) {
+		ts.tv_sec = 0;
+		ts.tv_nsec = timeout * MSEC_PER_NSEC;
+		ret = ppoll(ufds, 1, &ts, NULL);
+	} else {
+		ret = ppoll(ufds, 1, NULL, NULL);
+	}
+
+
+	if (ret < 0) {
+		PERROR("ppoll");
+	} else if (ret > 0) {
+		ret = read(wait_fd, buf, BUF_SIZE);
+		if (ret < 0) {
+			PERROR("[ppoll] read");
+		}
+	}
+}
+
+static
+void test_ppoll_big(FILE *validation_output_file)
+{
+	struct pollfd ufds[MAX_FDS];
+	char buf[BUF_SIZE];
+	int ret, i, fds[MAX_FDS];
+
+	for (i = 0; i < MAX_FDS; i++) {
+		fds[i] = dup(wait_fd);
+		if (fds[i] < 0) {
+			PERROR("dup");
+		}
+		ufds[i].fd = fds[i];
+		ufds[i].events = POLLIN|POLLPRI;
+	}
+
+	ret = ppoll(ufds, MAX_FDS, NULL, NULL);
+
+	if (ret < 0) {
+		PERROR("ppoll");
+	} else if (ret > 0) {
+		ret = read(wait_fd, buf, BUF_SIZE);
+		if (ret < 0) {
+			PERROR("[ppoll] read");
+		}
+	}
+
+	for (i = 0; i < MAX_FDS; i++) {
+		ret = close(fds[i]);
+		if (ret != 0) {
+			PERROR("close");
+		}
+	}
+
+	return;
+}
+
+static
+void test_epoll(FILE *validation_output_file)
+{
+	int ret, epollfd;
+	char buf[BUF_SIZE];
+	struct epoll_event epoll_event;
+
+	epollfd = epoll_create(NB_FD);
+	if (epollfd < 0) {
+		PERROR("[epoll] create");
+		goto end;
+	}
+
+	ret = fprintf(validation_output_file,
+			", \"epoll_wait_fd\": %i", epollfd);
+	if (ret < 0) {
+		PERROR("[epoll] Failed to write test validation output");
+		goto error;
+	}
+
+	epoll_event.events = EPOLLIN | EPOLLPRI | EPOLLET;
+	epoll_event.data.fd = wait_fd;
+	ret = epoll_ctl(epollfd, EPOLL_CTL_ADD, wait_fd, &epoll_event);
+	if (ret < 0) {
+		PERROR("[epoll] add");
+		goto error;
+	}
+
+	if (timeout > 0) {
+		ret = epoll_wait(epollfd, &epoll_event, 1, timeout);
+	} else {
+		ret = epoll_wait(epollfd, &epoll_event, 1, -1);
+	}
+
+	if (ret == 1) {
+		ret = read(wait_fd, buf, BUF_SIZE);
+		if (ret < 0) {
+			PERROR("[epoll] read");
+		}
+	} else if (ret != 0) {
+		PERROR("epoll_wait");
+	}
+
+error:
+	ret = close(epollfd);
+	if (ret) {
+		PERROR("close");
+	}
+end:
+	return;
+}
+
+static
+void test_epoll_pwait(FILE *validation_output_file)
+{
+	int ret, epollfd;
+	char buf[BUF_SIZE];
+	struct epoll_event epoll_event;
+
+	epollfd = epoll_create(NB_FD);
+	if (epollfd < 0) {
+		PERROR("[epoll_pwait] create");
+		goto end;
+	}
+
+	ret = fprintf(validation_output_file,
+			", \"epoll_pwait_fd\": %i", epollfd);
+	if (ret < 0) {
+		PERROR("[epoll_pwait] Failed to write test validation output");
+		goto error;
+	}
+
+	epoll_event.events = EPOLLIN | EPOLLPRI | EPOLLET;
+	epoll_event.data.fd = wait_fd;
+	ret = epoll_ctl(epollfd, EPOLL_CTL_ADD, wait_fd, &epoll_event);
+	if (ret < 0) {
+		PERROR("[epoll_pwait] add");
+		goto error;
+	}
+
+	if (timeout > 0) {
+		ret = epoll_pwait(epollfd, &epoll_event, 1, timeout, NULL);
+	} else {
+		ret = epoll_pwait(epollfd, &epoll_event, 1, -1, NULL);
+	}
+
+	if (ret == 1) {
+		ret = read(wait_fd, buf, BUF_SIZE);
+		if (ret < 0) {
+			PERROR("[epoll_pwait] read");
+		}
+	} else if (ret != 0) {
+		PERROR("epoll_pwait");
+	}
+
+error:
+	ret = close(epollfd);
+	if (ret) {
+		PERROR("close");
+	}
+end:
+	return;
+}
+
+static
+void run_working_cases(FILE *validation_output_file)
+{
+	int ret;
+	int pipe_fds[2];
+
+	if (timeout > 0) {
+		/*
+		 * We need an input pipe for some cases and stdin might
+		 * have random data, so we create a dummy pipe for this
+		 * test to make sure we are running under clean conditions.
+		 */
+		ret = pipe(pipe_fds);
+		if (ret != 0) {
+			PERROR("pipe");
+			goto end;
+		}
+		wait_fd = pipe_fds[0];
+	}
+	test_select();
+	test_pselect();
+	test_select_big();
+	test_poll();
+	test_ppoll();
+
+	ret = fprintf(validation_output_file, "{ \"pid\": %i", getpid());
+	if (ret < 0) {
+		PERROR("Failed to write pid to test validation file");
+		goto end;
+	}
+
+	test_epoll(validation_output_file);
+	test_epoll_pwait(validation_output_file);
+
+	if (timeout > 0) {
+		ret = close(pipe_fds[0]);
+		if (ret) {
+			PERROR("close");
+		}
+		ret = close(pipe_fds[1]);
+		if (ret) {
+			PERROR("close");
+		}
+	}
+
+	ret = fputs(" }", validation_output_file);
+	if (ret < 0) {
+		PERROR("Failed to close JSON dictionary in test validation file");
+		goto end;
+	}
+
+end:
+	return;
+}
+
+/*
+ * Ask for 100 FDs in a buffer for allocated for only 1 FD, should
+ * segfault (eventually with a "*** stack smashing detected ***" message).
+ * The event should contain an array of 100 FDs filled with garbage.
+ */
+static
+void ppoll_fds_buffer_overflow(FILE *validation_output_file)
+{
+	struct pollfd ufds[NB_FD];
+	char buf[BUF_SIZE];
+	int ret;
+
+	ufds[0].fd = wait_fd;
+	ufds[0].events = POLLIN|POLLPRI;
+
+	ret = syscall(SYS_ppoll, ufds, 100, NULL, NULL);
+
+	if (ret < 0) {
+		PERROR("ppoll");
+	} else if (ret > 0) {
+		ret = read(wait_fd, buf, BUF_SIZE);
+		if (ret < 0) {
+			PERROR("[ppoll] read");
+		}
+	}
+}
+
+/*
+ * Ask for ULONG_MAX FDs in a buffer for allocated for only 1 FD, should
+ * cleanly fail with a "Invalid argument".
+ * The event should contain an empty array of FDs and overflow = 1.
+ */
+static
+void ppoll_fds_ulong_max(FILE *validation_output_file)
+{
+	struct pollfd ufds[NB_FD];
+	char buf[BUF_SIZE];
+	int ret;
+
+	ufds[0].fd = wait_fd;
+	ufds[0].events = POLLIN|POLLPRI;
+
+	ret = syscall(SYS_ppoll, ufds, ULONG_MAX, NULL, NULL);
+	if (ret < 0) {
+		/* Expected error. */
+	} else if (ret > 0) {
+		ret = read(wait_fd, buf, BUF_SIZE);
+		if (ret < 0) {
+			PERROR("[ppoll] read");
+		}
+	}
+}
+
+/*
+ * Pass an invalid file descriptor to pselect6(). The syscall should return
+ * -EBADF. The recorded event should contain a "ret = -EBADF (-9)".
+ */
+static
+void pselect_invalid_fd(FILE *validation_output_file)
+{
+	fd_set rfds;
+	int ret;
+	int fd;
+	char buf[BUF_SIZE];
+
+	/*
+	 * Open a file, close it and use the closed FD in the pselect6 call.
+	 */
+	fd = open("/dev/null", O_RDONLY);
+	if (fd == -1) {
+		PERROR("open");
+		goto error;
+	}
+
+	ret = close(fd);
+	if (ret == -1) {
+		PERROR("close");
+		goto error;
+	}
+
+	FD_ZERO(&rfds);
+	FD_SET(fd, &rfds);
+
+	ret = syscall(SYS_pselect6, fd + 1, &rfds, NULL, NULL, NULL, NULL);
+	if (ret == -1) {
+		/* Expected error. */
+	} else if (ret) {
+		ret = read(wait_fd, buf, BUF_SIZE);
+		if (ret < 0) {
+			PERROR("[pselect] read");
+		}
+	}
+error:
+	return;
+}
+
+/*
+ * Invalid pointer as writefds, should output a ppoll event
+ * with 0 FDs.
+ */
+static
+void pselect_invalid_pointer(FILE *validation_output_file)
+{
+	fd_set rfds;
+	int ret;
+	char buf[BUF_SIZE];
+	void *invalid = (void *) 0x42;
+
+	FD_ZERO(&rfds);
+	FD_SET(wait_fd, &rfds);
+
+	ret = syscall(SYS_pselect6, 1, &rfds, (fd_set *) invalid, NULL, NULL,
+			NULL);
+	if (ret == -1) {
+		/* Expected error. */
+	} else if (ret) {
+		ret = read(wait_fd, buf, BUF_SIZE);
+		if (ret < 0) {
+			PERROR("[pselect] read");
+		}
+	}
+}
+
+/*
+ * Pass an invalid pointer to epoll_pwait, should fail with
+ * "Bad address", the event returns 0 FDs.
+ */
+static
+void epoll_pwait_invalid_pointer(FILE *validation_output_file)
+{
+	int ret, epollfd;
+	char buf[BUF_SIZE];
+	struct epoll_event epoll_event;
+	void *invalid = (void *) 0x42;
+
+	epollfd = epoll_create(NB_FD);
+	if (epollfd < 0) {
+		PERROR("[epoll_pwait] create");
+		goto end;
+	}
+
+	ret = fprintf(validation_output_file,
+			"{ \"epollfd\": %i, \"pid\": %i }", epollfd,
+			getpid());
+	if (ret < 0) {
+		PERROR("[epoll_pwait] Failed to write test validation output");
+		goto error;
+	}
+
+	epoll_event.events = EPOLLIN | EPOLLPRI | EPOLLET;
+	epoll_event.data.fd = wait_fd;
+	ret = epoll_ctl(epollfd, EPOLL_CTL_ADD, wait_fd, &epoll_event);
+	if (ret < 0) {
+		PERROR("[epoll_pwait] add");
+		goto error;
+	}
+
+	ret = syscall(SYS_epoll_pwait, epollfd,
+			(struct epoll_event *) invalid, 1, -1, NULL);
+
+	if (ret == 1) {
+		ret = read(wait_fd, buf, BUF_SIZE);
+		if (ret < 0) {
+			PERROR("[epoll_pwait] read");
+		}
+	} else if (ret != 0) {
+		/* Expected error. */
+	}
+
+error:
+	ret = close(epollfd);
+	if (ret) {
+		PERROR("close");
+	}
+end:
+	return;
+}
+
+/*
+ * Set maxevents to INT_MAX, should output "Invalid argument"
+ * The event should return an empty array.
+ */
+static
+void epoll_pwait_int_max(FILE *validation_output_file)
+{
+	int ret, epollfd;
+	char buf[BUF_SIZE];
+	struct epoll_event epoll_event;
+
+	epollfd = epoll_create(NB_FD);
+	if (epollfd < 0) {
+		PERROR("[epoll_pwait] create");
+		goto end;
+	}
+
+	ret = fprintf(validation_output_file,
+			"{ \"epollfd\": %i, \"pid\": %i }", epollfd,
+			getpid());
+	if (ret < 0) {
+		PERROR("[epoll_pwait] Failed to write test validation output");
+		goto error;
+	}
+
+	epoll_event.events = EPOLLIN | EPOLLPRI | EPOLLET;
+	epoll_event.data.fd = wait_fd;
+	ret = epoll_ctl(epollfd, EPOLL_CTL_ADD, wait_fd, &epoll_event);
+	if (ret < 0) {
+		PERROR("[epoll_pwait] add");
+		goto error;
+	}
+
+	ret = syscall(SYS_epoll_pwait, epollfd, &epoll_event, INT_MAX, -1,
+			NULL);
+
+	if (ret == 1) {
+		ret = read(wait_fd, buf, BUF_SIZE);
+		if (ret < 0) {
+			PERROR("[epoll_pwait] read");
+		}
+	} else if (ret != 0) {
+		/* Expected error. */
+	}
+
+error:
+	ret = close(epollfd);
+	if (ret) {
+		PERROR("close");
+	}
+end:
+	return;
+}
+
+static
+void *ppoll_writer(void *arg)
+{
+	struct ppoll_thread_data *data = (struct ppoll_thread_data *) arg;
+
+	while (!stop_thread) {
+		memset(data->ufds, data->value,
+				MAX_FDS * sizeof(struct pollfd));
+		usleep(100);
+	}
+
+	return NULL;
+}
+
+static
+void do_ppoll(int *fds, struct pollfd *ufds)
+{
+	int i, ret;
+	struct timespec ts;
+	char buf[BUF_SIZE];
+
+	ts.tv_sec = 0;
+	ts.tv_nsec = 1 * MSEC_PER_NSEC;
+
+	for (i = 0; i < MAX_FDS; i++) {
+		ufds[i].fd = fds[i];
+		ufds[i].events = POLLIN|POLLPRI;
+	}
+
+	ret = ppoll(ufds, MAX_FDS, &ts, NULL);
+
+	if (ret < 0) {
+		PERROR("ppoll");
+	} else if (ret > 0) {
+		ret = read(wait_fd, buf, BUF_SIZE);
+		if (ret < 0) {
+			PERROR("[ppoll] read");
+		}
+	}
+}
+
+static
+void stress_ppoll(int *fds, int value)
+{
+	pthread_t writer;
+	int iter, ret;
+	struct ppoll_thread_data thread_data;
+	struct pollfd ufds[MAX_FDS];
+
+	thread_data.ufds = ufds;
+	thread_data.value = value;
+
+	stop_thread = 0;
+	ret = pthread_create(&writer, NULL, &ppoll_writer, (void *) &thread_data);
+	if (ret != 0) {
+		fprintf(stderr, "[error] pthread_create\n");
+		goto end;
+	}
+	for (iter = 0; iter < NR_ITER; iter++) {
+		do_ppoll(fds, ufds);
+	}
+	stop_thread = 1;
+	ret = pthread_join(writer, NULL);
+	if (ret) {
+		fprintf(stderr, "[error] pthread_join\n");
+		goto end;
+	}
+end:
+	return;
+}
+
+/*
+ * 3 rounds of NR_ITER iterations with concurrent updates of the pollfd
+ * structure:
+ *   - memset to 0
+ *   - memset to 1
+ *   - memset to INT_MAX
+ * Waits for input, but also set a timeout in case the input FD is overwritten
+ * before entering in the syscall. We use MAX_FDS FDs (dup of stdin), so the
+ * resulting trace is big (20MB).
+ *
+ * ppoll should work as expected and the trace should be readable at the end.
+ */
+static
+void ppoll_concurrent_write(FILE *validation_output_file)
+{
+	int i, ret, fds[MAX_FDS];
+
+	for (i = 0; i < MAX_FDS; i++) {
+		fds[i] = dup(wait_fd);
+		if (fds[i] < 0) {
+			PERROR("dup");
+		}
+	}
+
+	stress_ppoll(fds, 0);
+	stress_ppoll(fds, 1);
+	stress_ppoll(fds, INT_MAX);
+
+	for (i = 0; i < MAX_FDS; i++) {
+		ret = close(fds[i]);
+		if (ret != 0) {
+			PERROR("close");
+		}
+	}
+
+	return;
+}
+
+static
+void *epoll_pwait_writer(void *addr)
+{
+	srand(time(NULL));
+
+	while (!stop_thread) {
+		usleep(rand() % 30);
+		munmap(addr, MAX_FDS * sizeof(struct epoll_event));
+	}
+
+	return NULL;
+}
+
+/*
+ * epoll_pwait on MAX_FDS fds while a concurrent thread munmaps the
+ * buffer allocated for the returned data. This should randomly segfault.
+ * The trace should be readable and no kernel OOPS should occur.
+ */
+static
+void epoll_pwait_concurrent_munmap(FILE *validation_output_file)
+{
+	int ret, epollfd, i, fds[MAX_FDS];
+	char buf[BUF_SIZE];
+	struct epoll_event *epoll_event;
+	pthread_t writer;
+
+	for (i = 0; i < MAX_FDS; i++) {
+		fds[i] = -1;
+	}
+	epollfd = epoll_create(MAX_FDS);
+	if (epollfd < 0) {
+		PERROR("[epoll_pwait] create");
+		goto end;
+	}
+
+	ret = fprintf(validation_output_file,
+			"{ \"epollfd\": %i, \"pid\": %i }", epollfd,
+			getpid());
+	if (ret < 0) {
+		PERROR("[epoll_pwait] Failed to write test validation output");
+		goto error;
+	}
+
+	epoll_event = (struct epoll_event *) mmap(NULL,
+			MAX_FDS * sizeof(struct epoll_event),
+			PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1,
+			0);
+	if (epoll_event == MAP_FAILED) {
+		PERROR("mmap");
+		goto error;
+	}
+
+	for (i = 0; i < MAX_FDS; i++) {
+		fds[i] = dup(wait_fd);
+		if (fds[i] < 0) {
+			PERROR("dup");
+		}
+		epoll_event[i].events = EPOLLIN | EPOLLPRI | EPOLLET;
+		epoll_event[i].data.fd = fds[i];
+		ret = epoll_ctl(epollfd, EPOLL_CTL_ADD, fds[i], epoll_event);
+		if (ret < 0) {
+			PERROR("[epoll_pwait] add");
+			goto error_unmap;
+		}
+	}
+	stop_thread = 0;
+	ret = pthread_create(&writer, NULL, &epoll_pwait_writer,
+			(void *) epoll_event);
+	if (ret != 0) {
+		fprintf(stderr, "[error] pthread_create\n");
+		goto error_unmap;
+	}
+
+	ret = epoll_pwait(epollfd, epoll_event, 1, 1, NULL);
+
+	if (ret == 1) {
+		ret = read(wait_fd, buf, BUF_SIZE);
+		if (ret < 0) {
+			PERROR("[epoll_pwait] read");
+		}
+	} else if (ret != 0) {
+		/* Expected error. */
+	}
+
+	stop_thread = 1;
+	ret = pthread_join(writer, NULL);
+	if (ret) {
+		fprintf(stderr, "[error] pthread_join\n");
+		goto error_unmap;
+	}
+error_unmap:
+	for (i = 0; i < MAX_FDS; i++) {
+		ret = close(fds[i]);
+		if (ret != 0) {
+			PERROR("close");
+		}
+	}
+
+	ret = munmap(epoll_event, MAX_FDS * sizeof(struct epoll_event));
+	if (ret != 0) {
+		PERROR("munmap");
+	}
+
+error:
+	ret = close(epollfd);
+	if (ret) {
+		PERROR("close");
+	}
+end:
+	return;
+}
+
+static
+void print_list(void)
+{
+	fprintf(stderr, "Test list (-t X):\n");
+	fprintf(stderr, "\t1: Working cases for select, pselect6, poll, ppoll "
+			"and epoll, waiting for input\n");
+	fprintf(stderr, "\t2: Timeout cases (1ms) for select, pselect6, poll, "
+			"ppoll and epoll\n");
+	fprintf(stderr, "\t3: pselect with an invalid fd\n");
+	fprintf(stderr, "\t4: ppoll with %d FDs\n", MAX_FDS);
+	fprintf(stderr, "\t5: ppoll buffer overflow, should segfault, waits "
+			"for input\n");
+	fprintf(stderr, "\t6: pselect with an invalid pointer, waits for "
+			"input\n");
+	fprintf(stderr, "\t7: ppoll with ulong_max fds, waits for input\n");
+	fprintf(stderr, "\t8: epoll_pwait with an invalid pointer, waits for "
+			"input\n");
+	fprintf(stderr, "\t9: epoll_pwait with maxevents set to INT_MAX, "
+			"waits for input\n");
+	fprintf(stderr, "\t10: ppoll with concurrent updates of the structure "
+			"from user-space, stress test (3000 iterations), "
+			"waits for input + timeout 1ms\n");
+	fprintf(stderr, "\t11: epoll_pwait with concurrent munmap of the buffer "
+			"from user-space, should randomly segfault, run "
+			"multiple times, waits for input + timeout 1ms\n");
+}
+
+int main(int argc, const char **argv)
+{
+	int c, ret, test = -1;
+	poptContext optCon;
+	struct rlimit open_lim;
+	FILE *test_validation_output_file = NULL;
+	const char *test_validation_output_file_path = NULL;
+	struct poptOption optionsTable[] = {
+		{ "test", 't', POPT_ARG_INT, &test, 0,
+			"Test to run", NULL },
+		{ "list", 'l', 0, 0, 'l',
+			"List of tests (-t X)", NULL },
+		{ "validation-file", 'o', POPT_ARG_STRING, &test_validation_output_file_path, 0,
+			"Test case output", NULL },
+		POPT_AUTOHELP
+		{ NULL, 0, 0, NULL, 0 }
+	};
+	const struct test_case *test_case;
+
+	optCon = poptGetContext(NULL, argc, argv, optionsTable, 0);
+
+	if (argc < 2) {
+		poptPrintUsage(optCon, stderr, 0);
+		ret = -1;
+		goto end;
+	}
+
+	ret = 0;
+
+	while ((c = poptGetNextOpt(optCon)) >= 0) {
+		switch (c) {
+		case 'l':
+			print_list();
+			goto end;
+		}
+	}
+
+	if (!test_validation_output_file_path) {
+		fprintf(stderr, "A test validation file path is required (--validation-file/-o)\n");
+		ret = -1;
+		goto end;
+	}
+
+	test_validation_output_file = fopen(test_validation_output_file_path, "w+");
+	if (!test_validation_output_file) {
+		PERROR("Failed to create test validation output file at '%s'",
+				test_validation_output_file_path);
+		ret = -1;
+		goto end;
+	}
+
+	open_lim.rlim_cur = MAX_FDS + MIN_NR_FDS;
+	open_lim.rlim_max = MAX_FDS + MIN_NR_FDS;
+
+	ret = setrlimit(RLIMIT_NOFILE, &open_lim);
+	if (ret < 0) {
+		PERROR("setrlimit");
+		goto end;
+	}
+
+	/*
+	 * Some tests might segfault, but we need the getpid() to be output
+	 * for the validation, disabling the buffering on the validation file
+	 * works.
+	 */
+	setbuf(test_validation_output_file, NULL);
+	wait_fd = STDIN_FILENO;
+
+	/* Test case id is 1-based. */
+	if (test < 1 || test > ARRAY_SIZE(test_cases)) {
+		poptPrintUsage(optCon, stderr, 0);
+		ret = -1;
+	}
+
+	test_case = &test_cases[test - 1];
+
+	timeout = test_case->timeout;
+	if (!test_case->produces_validation_info) {
+		/*
+		 * All test cases need to provide, at minimum, the pid of the
+		 * test application.
+		 */
+		ret = fprintf(test_validation_output_file, "{ \"pid\": %i }", getpid());
+		if (ret < 0) {
+			PERROR("Failed to write application pid to test validation file");
+			goto end;
+		}
+	}
+
+	test_case->run(test_validation_output_file);
+
+end:
+	if (test_validation_output_file) {
+		const int close_ret = fclose(test_validation_output_file);
+
+		if (close_ret) {
+			PERROR("Failed to close test output file");
+		}
+	}
+	poptFreeContext(optCon);
+	return ret;
+}