@@ -5,7 +5,7 @@ LDFLAGS += -lrt -lpthread
bins = posix_timers nanosleep inconsistency-check nsleep-lat raw_skew \
set-timer-lat threadtest mqueue-lat valid-adjtimex \
alarmtimer-suspend change_skew skew_consistency clocksource-switch \
- leap-a-day
+ leap-a-day leapcrash
all: ${bins}
@@ -31,6 +31,7 @@ run_destructive_tests: run_tests
./skew_consistency
./clocksource-switch
./leap-a-day -s -i 10
+ ./leapcrash
clean:
rm -f ${bins}
new file mode 100644
@@ -0,0 +1,120 @@
+/* Demo leapsecond deadlock
+ * by: John Stultz (john.stultz@linaro.org)
+ * (C) Copyright IBM 2012
+ * (C) Copyright 2013, 2015 Linaro Limited
+ * Licensed under the GPL
+ *
+ * This test demonstrates leapsecond deadlock that is possibe
+ * on kernels from 2.6.26 to 3.3.
+ *
+ * WARNING: THIS WILL LIKELY HARDHANG SYSTEMS AND MAY LOSE DATA
+ * RUN AT YOUR OWN RISK!
+ * To build:
+ * $ gcc leapcrash.c -o leapcrash -lrt
+ */
+
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include <sys/time.h>
+#include <sys/timex.h>
+#include <string.h>
+#include <signal.h>
+#ifdef KTEST
+#include "../kselftest.h"
+#else
+static inline int ksft_exit_pass(void)
+{
+ exit(0);
+}
+static inline int ksft_exit_fail(void)
+{
+ exit(1);
+}
+#endif
+
+
+
+/* clear NTP time_status & time_state */
+int clear_time_state(void)
+{
+ struct timex tx;
+ int ret;
+
+ /*
+ * We have to call adjtime twice here, as kernels
+ * prior to 6b1859dba01c7 (included in 3.5 and
+ * -stable), had an issue with the state machine
+ * and wouldn't clear the STA_INS/DEL flag directly.
+ */
+ tx.modes = ADJ_STATUS;
+ tx.status = STA_PLL;
+ ret = adjtimex(&tx);
+
+ tx.modes = ADJ_STATUS;
+ tx.status = 0;
+ ret = adjtimex(&tx);
+
+ return ret;
+}
+
+/* Make sure we cleanup on ctrl-c */
+void handler(int unused)
+{
+ clear_time_state();
+ exit(0);
+}
+
+
+int main(void)
+{
+ struct timex tx;
+ struct timespec ts;
+ time_t next_leap;
+ int count = 0;
+
+ setbuf(stdout, NULL);
+
+ signal(SIGINT, handler);
+ signal(SIGKILL, handler);
+ printf("This runs for a few minutes. Press ctrl-c to stop\n");
+
+ clear_time_state();
+
+
+ /* Get the current time */
+ clock_gettime(CLOCK_REALTIME, &ts);
+
+ /* Calculate the next possible leap second 23:59:60 GMT */
+ next_leap = ts.tv_sec;
+ next_leap += 86400 - (next_leap % 86400);
+
+ for (count = 0; count < 20; count++) {
+ struct timeval tv;
+
+
+ /* set the time to 2 seconds before the leap */
+ tv.tv_sec = next_leap - 2;
+ tv.tv_usec = 0;
+ if (settimeofday(&tv, NULL)) {
+ printf("Error: You're likely not running with proper (ie: root) permissions\n");
+ return ksft_exit_fail();
+ }
+ tx.modes = 0;
+ adjtimex(&tx);
+
+ /* hammer on adjtime w/ STA_INS */
+ while (tx.time.tv_sec < next_leap + 1) {
+ /* Set the leap second insert flag */
+ tx.modes = ADJ_STATUS;
+ tx.status = STA_INS;
+ adjtimex(&tx);
+ }
+ clear_time_state();
+ printf(".");
+ }
+ printf("[OK]\n");
+ return ksft_exit_pass();
+}
This change adds the leapcrash test which tests to see if a leapsecond deadlock which was observed from 2.6.26 to 3.3 is present on this system. Cc: Shuah Khan <shuahkh@osg.samsung.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Richard Cochran <richardcochran@gmail.com> Signed-off-by: John Stultz <john.stultz@linaro.org> --- tools/testing/selftests/timers/Makefile | 3 +- tools/testing/selftests/timers/leapcrash.c | 120 +++++++++++++++++++++++++++++ 2 files changed, 122 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/timers/leapcrash.c