[GIT pull] timer fix for 4.15

[GIT pull] timer fix for 4.15

[Thomas Gleixner]

Linus,

please pull the latest timers-urgent-for-linus git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git timers-urgent-for-linus

A single bugfix which prevents arbitrary sigev_notify values in
posix-timers.

Thanks,

	tglx

------------------>
Thomas Gleixner (1):
      posix-timer: Properly check sigevent->sigev_notify


 kernel/time/posix-timers.c | 29 +++++++++++++++++------------
 1 file changed, 17 insertions(+), 12 deletions(-)

diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 13d6881f908b..ec999f32c840 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -434,17 +434,22 @@ static struct pid *good_sigevent(sigevent_t * event)
 {
 	struct task_struct *rtn = current->group_leader;
 
-	if ((event->sigev_notify & SIGEV_THREAD_ID ) &&
-		(!(rtn = find_task_by_vpid(event->sigev_notify_thread_id)) ||
-		 !same_thread_group(rtn, current) ||
-		 (event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_SIGNAL))
+	switch (event->sigev_notify) {
+	case SIGEV_SIGNAL | SIGEV_THREAD_ID:
+		rtn = find_task_by_vpid(event->sigev_notify_thread_id);
+		if (!rtn || !same_thread_group(rtn, current))
+			return NULL;
+		/* FALLTHRU */
+	case SIGEV_SIGNAL:
+	case SIGEV_THREAD:
+		if (event->sigev_signo <= 0 || event->sigev_signo > SIGRTMAX)
+			return NULL;
+		/* FALLTHRU */
+	case SIGEV_NONE:
+		return task_pid(rtn);
+	default:
 		return NULL;
-
-	if (((event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) &&
-	    ((event->sigev_signo <= 0) || (event->sigev_signo > SIGRTMAX)))
-		return NULL;
-
-	return task_pid(rtn);
+	}
 }
 
 static struct k_itimer * alloc_posix_timer(void)
@@ -669,7 +674,7 @@ void common_timer_get(struct k_itimer *timr, struct itimerspec64 *cur_setting)
 	struct timespec64 ts64;
 	bool sig_none;
 
-	sig_none = (timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE;
+	sig_none = timr->it_sigev_notify == SIGEV_NONE;
 	iv = timr->it_interval;
 
 	/* interval timer ? */
@@ -856,7 +861,7 @@ int common_timer_set(struct k_itimer *timr, int flags,
 
 	timr->it_interval = timespec64_to_ktime(new_setting->it_interval);
 	expires = timespec64_to_ktime(new_setting->it_value);
-	sigev_none = (timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE;
+	sigev_none = timr->it_sigev_notify == SIGEV_NONE;
 
 	kc->timer_arm(timr, expires, flags & TIMER_ABSTIME, sigev_none);
 	timr->it_active = !sigev_none;

[GIT pull] timer fix for 4.15

[Thomas Gleixner]

Linus,

please pull the latest timers-urgent-for-linus git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git timers-urgent-for-linus

A single fix for a ~10 years old problem which causes high resolution
timers to stop after a CPU unplug/plug cycle due to a stale flag in the per
CPU hrtimer base struct. Paul McKenney was hunting this for about a year,
but the heisenbug nature made it resistant against debug attempts for quite
some time.

Thanks,

	tglx

------------------>
Thomas Gleixner (1):
      hrtimer: Reset hrtimer cpu base proper on CPU hotplug


 kernel/time/hrtimer.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index d32520840fde..aa9d2a2b1210 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -655,7 +655,9 @@ static void hrtimer_reprogram(struct hrtimer *timer,
 static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base)
 {
 	base->expires_next = KTIME_MAX;
+	base->hang_detected = 0;
 	base->hres_active = 0;
+	base->next_timer = NULL;
 }
 
 /*
@@ -1589,6 +1591,7 @@ int hrtimers_prepare_cpu(unsigned int cpu)
 		timerqueue_init_head(&cpu_base->clock_base[i].active);
 	}
 
+	cpu_base->active_bases = 0;
 	cpu_base->cpu = cpu;
 	hrtimer_init_hres(cpu_base);
 	return 0;

[GIT pull] timer fix for 4.15

[Thomas Gleixner]

Linus,

please pull the latest timers-urgent-for-linus git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git timers-urgent-for-linus

A one-liner fix which prevents deferrable timers becoming stale when the
system does not switch into NOHZ mode.

Thanks,

	tglx

------------------>
Thomas Gleixner (1):
      timers: Unconditionally check deferrable base


 kernel/time/timer.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index 89a9e1b4264a..0bcf00e3ce48 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -1696,7 +1696,7 @@ void run_local_timers(void)
 	hrtimer_run_queues();
 	/* Raise the softirq only if required. */
 	if (time_before(jiffies, base->clk)) {
-		if (!IS_ENABLED(CONFIG_NO_HZ_COMMON) || !base->nohz_active)
+		if (!IS_ENABLED(CONFIG_NO_HZ_COMMON))
 			return;
 		/* CPU is awake, so check the deferrable base. */
 		base++;