These tests validate that rseq is registered from various execution
contexts (main thread, constructor, destructor, other threads, other
threads created from constructor and destructor, forked process
(without exec), pthread_atfork handlers, pthread setspecific
destructors, C++ thread and process destructors, signal handlers,
atexit handlers).
tst-rseq.c only links against libc.so, testing registration of rseq in
a non-multithreaded environment.
tst-rseq-nptl.c also links against libpthread.so, testing registration
of rseq in a multithreaded environment.
See the Linux kernel selftests for extensive rseq stress-tests.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
CC: Carlos O'Donell <carlos@redhat.com>
CC: Florian Weimer <fweimer@redhat.com>
CC: Joseph Myers <joseph@codesourcery.com>
CC: Szabolcs Nagy <szabolcs.nagy@arm.com>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Ben Maurer <bmaurer@fb.com>
CC: Peter Zijlstra <peterz@infradead.org>
CC: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
CC: Boqun Feng <boqun.feng@gmail.com>
CC: Will Deacon <will.deacon@arm.com>
CC: Dave Watson <davejwatson@fb.com>
CC: Paul Turner <pjt@google.com>
CC: libc-alpha@sourceware.org
---
Changes since v1:
- Rename tst-rseq.c to tst-rseq-nptl.c.
- Introduce tst-rseq.c testing rseq registration in a non-multithreaded
environment.
Chances since v2:
- Update file headers.
- use xpthread key create/delete.
- remove set stacksize.
- Tests depend on both __NR_rseq and RSEQ_SIG being defined.
Changes since v3:
- Update ChangeLog.
Changes since v4:
- Remove volatile from sys_rseq() rseq_abi parameter.
- Use atomic_load_relaxed to load __rseq_abi.cpu_id, consequence of the
fact that __rseq_abi is not volatile anymore.
- Include atomic.h from tst-rseq.c for use of atomic_load_relaxed.
Move tst-rseq.c to internal tests within Makefile due to its use of
atomic.h.
- Test __rseq_handled initialization by glibc.
---
ChangeLog | 7 +
sysdeps/unix/sysv/linux/Makefile | 4 +-
sysdeps/unix/sysv/linux/tst-rseq-nptl.c | 368 ++++++++++++++++++++++++
sysdeps/unix/sysv/linux/tst-rseq.c | 122 ++++++++
4 files changed, 499 insertions(+), 2 deletions(-)
create mode 100644 sysdeps/unix/sysv/linux/tst-rseq-nptl.c
create mode 100644 sysdeps/unix/sysv/linux/tst-rseq.c
@@ -1,4 +1,11 @@
2019-04-23 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+
+ * sysdeps/unix/sysv/linux/Makefile: Add tst-rseq and tst-rseq-nptl.
+ * sysdeps/unix/sysv/linux/tst-rseq-nptl.c: New file.
+ * sysdeps/unix/sysv/linux/tst-rseq.c: Likewise.
+
+2019-04-23 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+
* support/Makefile: Add xpthread_key_create and xpthread_key_delete.
* support/xthread.h: Add prototype for xpthread_key_create and
xpthread_key_delete.
@@ -54,7 +54,7 @@ tests += tst-clone tst-clone2 tst-clone3 tst-fanotify tst-personality \
tst-quota tst-sync_file_range tst-sysconf-iov_max tst-ttyname \
test-errno-linux tst-memfd_create tst-mlock2 tst-pkey \
tst-rlimit-infinity tst-ofdlocks
-tests-internal += tst-ofdlocks-compat
+tests-internal += tst-ofdlocks-compat tst-rseq
# Generate the list of SYS_* macros for the system calls (__NR_*
@@ -230,5 +230,5 @@ ifeq ($(subdir),nptl)
tests += tst-align-clone tst-getpid1 \
tst-thread-affinity-pthread tst-thread-affinity-pthread2 \
tst-thread-affinity-sched
-tests-internal += tst-setgetname
+tests-internal += tst-setgetname tst-rseq-nptl
endif
new file mode 100644
@@ -0,0 +1,368 @@
+/* Restartable Sequences NPTL test.
+
+ Copyright (C) 2019 Free Software Foundation, Inc.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+/* These tests validate that rseq is registered from various execution
+ contexts (main thread, constructor, destructor, other threads, other
+ threads created from constructor and destructor, forked process
+ (without exec), pthread_atfork handlers, pthread setspecific
+ destructors, C++ thread and process destructors, signal handlers,
+ atexit handlers).
+
+ See the Linux kernel selftests for extensive rseq stress-tests. */
+
+#include <sys/syscall.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <support/check.h>
+#include <support/xthread.h>
+
+#ifdef __NR_rseq
+#include <sys/rseq.h>
+#endif
+
+#if defined __NR_rseq && defined RSEQ_SIG
+#include <pthread.h>
+#include <syscall.h>
+#include <stdlib.h>
+#include <error.h>
+#include <errno.h>
+#include <string.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <signal.h>
+#include <atomic.h>
+
+static pthread_key_t rseq_test_key;
+
+static int
+rseq_thread_registered (void)
+{
+ return (int32_t) atomic_load_relaxed (&__rseq_abi.cpu_id) >= 0;
+}
+
+static int
+do_rseq_main_test (void)
+{
+ if (raise (SIGUSR1))
+ FAIL_EXIT1 ("error raising signal");
+ if (pthread_setspecific (rseq_test_key, (void *) 1l))
+ FAIL_EXIT1 ("error in pthread_setspecific");
+ if (!rseq_thread_registered ())
+ {
+ FAIL_RET ("rseq not registered in main thread");
+ }
+ return 0;
+}
+
+static void
+cancel_routine (void *arg)
+{
+ if (!rseq_thread_registered ())
+ {
+ printf ("rseq not registered in cancel routine\n");
+ support_record_failure ();
+ }
+}
+
+static int cancel_thread_ready;
+
+static void
+test_cancel_thread (void)
+{
+ pthread_cleanup_push (cancel_routine, NULL);
+ atomic_store_release (&cancel_thread_ready, 1);
+ for (;;)
+ usleep (100);
+ pthread_cleanup_pop (0);
+}
+
+static void *
+thread_function (void * arg)
+{
+ int i = (int) (intptr_t) arg;
+
+ if (raise (SIGUSR1))
+ FAIL_EXIT1 ("error raising signal");
+ if (i == 0)
+ test_cancel_thread ();
+ if (pthread_setspecific (rseq_test_key, (void *) 1l))
+ FAIL_EXIT1 ("error in pthread_setspecific");
+ return rseq_thread_registered () ? NULL : (void *) 1l;
+}
+
+static void
+sighandler (int sig)
+{
+ if (!rseq_thread_registered ())
+ {
+ printf ("rseq not registered in signal handler\n");
+ support_record_failure ();
+ }
+}
+
+static void
+setup_signals (void)
+{
+ struct sigaction sa;
+
+ sigemptyset (&sa.sa_mask);
+ sigaddset (&sa.sa_mask, SIGUSR1);
+ sa.sa_flags = 0;
+ sa.sa_handler = sighandler;
+ if (sigaction (SIGUSR1, &sa, NULL) != 0)
+ {
+ FAIL_EXIT1 ("sigaction failure: %s", strerror (errno));
+ }
+}
+
+#define N 7
+static const int t[N] = { 1, 2, 6, 5, 4, 3, 50 };
+
+static int
+do_rseq_threads_test (int nr_threads)
+{
+ pthread_t th[nr_threads];
+ int i;
+ int result = 0;
+ pthread_attr_t at;
+
+ if (pthread_attr_init (&at) != 0)
+ {
+ FAIL_EXIT1 ("attr_init failed");
+ }
+
+ cancel_thread_ready = 0;
+ for (i = 0; i < nr_threads; ++i)
+ if (pthread_create (&th[i], NULL, thread_function,
+ (void *) (intptr_t) i) != 0)
+ {
+ FAIL_EXIT1 ("creation of thread %d failed", i);
+ }
+
+ if (pthread_attr_destroy (&at) != 0)
+ {
+ FAIL_EXIT1 ("attr_destroy failed");
+ }
+
+ while (!atomic_load_acquire (&cancel_thread_ready))
+ usleep (100);
+
+ if (pthread_cancel (th[0]))
+ FAIL_EXIT1 ("error in pthread_cancel");
+
+ for (i = 0; i < nr_threads; ++i)
+ {
+ void *v;
+ if (pthread_join (th[i], &v) != 0)
+ {
+ printf ("join of thread %d failed\n", i);
+ result = 1;
+ }
+ else if (i != 0 && v != NULL)
+ {
+ printf ("join %d successful, but child failed\n", i);
+ result = 1;
+ }
+ else if (i == 0 && v == NULL)
+ {
+ printf ("join %d successful, child did not fail as expected\n", i);
+ result = 1;
+ }
+ }
+ return result;
+}
+
+static int
+sys_rseq (struct rseq *rseq_abi, uint32_t rseq_len, int flags, uint32_t sig)
+{
+ return syscall (__NR_rseq, rseq_abi, rseq_len, flags, sig);
+}
+
+static int
+rseq_available (void)
+{
+ int rc;
+
+ rc = sys_rseq (NULL, 0, 0, 0);
+ if (rc != -1)
+ FAIL_EXIT1 ("Unexpected rseq return value %d", rc);
+ switch (errno)
+ {
+ case ENOSYS:
+ return 0;
+ case EINVAL:
+ return 1;
+ default:
+ FAIL_EXIT1 ("Unexpected rseq error %s", strerror (errno));
+ }
+}
+
+static int
+do_rseq_fork_test (void)
+{
+ int status;
+ pid_t pid, retpid;
+
+ pid = fork ();
+ switch (pid)
+ {
+ case 0:
+ exit (do_rseq_main_test ());
+ case -1:
+ FAIL_EXIT1 ("Unexpected fork error %s", strerror (errno));
+ }
+ retpid = TEMP_FAILURE_RETRY (waitpid (pid, &status, 0));
+ if (retpid != pid)
+ {
+ FAIL_EXIT1 ("waitpid returned %ld, expected %ld",
+ (long int) retpid, (long int) pid);
+ }
+ if (WEXITSTATUS (status))
+ {
+ printf ("rseq not registered in child\n");
+ return 1;
+ }
+ return 0;
+}
+
+static int
+do_rseq_test (void)
+{
+ int i, result = 0;
+
+ if (!rseq_available ())
+ {
+ FAIL_UNSUPPORTED ("kernel does not support rseq, skipping test");
+ }
+ setup_signals ();
+ if (raise (SIGUSR1))
+ FAIL_EXIT1 ("error raising signal");
+ if (do_rseq_main_test ())
+ result = 1;
+ for (i = 0; i < N; i++)
+ {
+ if (do_rseq_threads_test (t[i]))
+ result = 1;
+ }
+ if (do_rseq_fork_test ())
+ result = 1;
+ return result;
+}
+
+static void
+atfork_prepare (void)
+{
+ if (!rseq_thread_registered ())
+ {
+ printf ("rseq not registered in pthread atfork prepare\n");
+ support_record_failure ();
+ }
+}
+
+static void
+atfork_parent (void)
+{
+ if (!rseq_thread_registered ())
+ {
+ printf ("rseq not registered in pthread atfork parent\n");
+ support_record_failure ();
+ }
+}
+
+static void
+atfork_child (void)
+{
+ if (!rseq_thread_registered ())
+ {
+ printf ("rseq not registered in pthread atfork child\n");
+ support_record_failure ();
+ }
+}
+
+static void
+rseq_key_destructor (void *arg)
+{
+ /* Cannot use deferred failure reporting after main () returns. */
+ if (!rseq_thread_registered ())
+ FAIL_EXIT1 ("rseq not registered in pthread key destructor");
+}
+
+static void
+atexit_handler (void)
+{
+ /* Cannot use deferred failure reporting after main () returns. */
+ if (!rseq_thread_registered ())
+ FAIL_EXIT1 ("rseq not registered in atexit handler");
+}
+
+static void __attribute__ ((constructor))
+do_rseq_constructor_test (void)
+{
+ support_record_failure_init ();
+ if (!__rseq_handled)
+ FAIL_EXIT1 ("rseq registration ownership is not published by libc");
+ if (atexit (atexit_handler))
+ FAIL_EXIT1 ("error calling atexit");
+ xpthread_key_create (&rseq_test_key, rseq_key_destructor);
+ if (pthread_atfork (atfork_prepare, atfork_parent, atfork_child))
+ FAIL_EXIT1 ("error calling pthread_atfork");
+ if (do_rseq_test ())
+ FAIL_EXIT1 ("rseq not registered within constructor");
+}
+
+static void __attribute__ ((destructor))
+do_rseq_destructor_test (void)
+{
+ /* Cannot use deferred failure reporting after main () returns. */
+ if (do_rseq_test ())
+ FAIL_EXIT1 ("rseq not registered within destructor");
+ xpthread_key_delete (rseq_test_key);
+}
+
+/* Test C++ destructor called at thread and process exit. */
+void
+__call_tls_dtors (void)
+{
+ /* Cannot use deferred failure reporting after main () returns. */
+ if (!rseq_thread_registered ())
+ FAIL_EXIT1 ("rseq not registered in C++ thread/process exit destructor");
+}
+#else
+static int
+do_rseq_test (void)
+{
+#ifndef __NR_rseq
+ FAIL_UNSUPPORTED ("kernel headers do not support rseq, skipping test");
+#endif
+#ifndef RSEQ_SIG
+ FAIL_UNSUPPORTED ("glibc does not define RSEQ_SIG, skipping test");
+#endif
+ return 0;
+}
+#endif
+
+static int
+do_test (void)
+{
+ if (!__rseq_handled)
+ FAIL_EXIT1 ("rseq registration ownership is not published by libc");
+ return do_rseq_test ();
+}
+
+#include <support/test-driver.c>
new file mode 100644
@@ -0,0 +1,122 @@
+/* Restartable Sequences single-threaded tests.
+
+ Copyright (C) 2019 Free Software Foundation, Inc.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+/* These tests validate that rseq is registered from main in an executable
+ not linked against libpthread. */
+
+#include <sys/syscall.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <support/check.h>
+
+#ifdef __NR_rseq
+#include <sys/rseq.h>
+#endif
+
+#if defined __NR_rseq && defined RSEQ_SIG
+#include <syscall.h>
+#include <stdlib.h>
+#include <error.h>
+#include <errno.h>
+#include <stdint.h>
+#include <string.h>
+#include <atomic.h>
+
+static int
+rseq_thread_registered (void)
+{
+ return (int32_t) atomic_load_relaxed (&__rseq_abi.cpu_id) >= 0;
+}
+
+static int
+do_rseq_main_test (void)
+{
+ if (!rseq_thread_registered ())
+ {
+ FAIL_RET ("rseq not registered in main thread");
+ }
+ return 0;
+}
+
+static int
+sys_rseq (struct rseq *rseq_abi, uint32_t rseq_len, int flags, uint32_t sig)
+{
+ return syscall (__NR_rseq, rseq_abi, rseq_len, flags, sig);
+}
+
+static int
+rseq_available (void)
+{
+ int rc;
+
+ rc = sys_rseq (NULL, 0, 0, 0);
+ if (rc != -1)
+ FAIL_EXIT1 ("Unexpected rseq return value %d", rc);
+ switch (errno)
+ {
+ case ENOSYS:
+ return 0;
+ case EINVAL:
+ return 1;
+ default:
+ FAIL_EXIT1 ("Unexpected rseq error %s", strerror (errno));
+ }
+}
+
+static int
+do_rseq_test (void)
+{
+ int result = 0;
+
+ if (!rseq_available ())
+ {
+ FAIL_UNSUPPORTED ("kernel does not support rseq, skipping test");
+ }
+ if (do_rseq_main_test ())
+ result = 1;
+ return result;
+}
+#else
+static int
+do_rseq_test (void)
+{
+#ifndef __NR_rseq
+ FAIL_UNSUPPORTED ("kernel headers do not support rseq, skipping test");
+#endif
+#ifndef RSEQ_SIG
+ FAIL_UNSUPPORTED ("glibc does not define RSEQ_SIG, skipping test");
+#endif
+ return 0;
+}
+#endif
+
+/* Test whether glibc correctly sets __rseq_handled ownership by
+ providing an instance of the symbol within the executable.
+ The dynamic linker ensures all libraries and the executable
+ agree on choosing a single copy of this global symbol. */
+int __rseq_handled;
+
+static int
+do_test (void)
+{
+ if (!__rseq_handled)
+ FAIL_RET ("rseq registration ownership is not published by libc");
+ return do_rseq_test ();
+}
+
+#include <support/test-driver.c>