Thomas Gleixner 75b5016ce3 hrtimers: Push pending hrtimers away from outgoing CPU earlier ... [ Upstream commit 5c0930ccaa ] 2b8272ff4a ("cpu/hotplug: Prevent self deadlock on CPU hot-unplug") solved the straight forward CPU hotplug deadlock vs. the scheduler bandwidth timer. Yu discovered a more involved variant where a task which has a bandwidth timer started on the outgoing CPU holds a lock and then gets throttled. If the lock required by one of the CPU hotplug callbacks the hotplug operation deadlocks because the unthrottling timer event is not handled on the dying CPU and can only be recovered once the control CPU reaches the hotplug state which pulls the pending hrtimers from the dead CPU. Solve this by pushing the hrtimers away from the dying CPU in the dying callbacks. Nothing can queue a hrtimer on the dying CPU at that point because all other CPUs spin in stop_machine() with interrupts disabled and once the operation is finished the CPU is marked offline. Reported-by: Yu Liao <liaoyu15@huawei.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Liu Tie <liutie4@huawei.com> Link: https://lore.kernel.org/r/87a5rphara.ffs@tglx Signed-off-by: Sasha Levin <sashal@kernel.org>		2023-12-13 18:39:03 +01:00
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Kconfig	…
Makefile	…
alarmtimer.c	…
clockevents.c	…
clocksource-wdtest.c	…
clocksource.c	clocksource: Suspend the watchdog temporarily when high read latency detected	2023-03-10 09:33:50 +01:00
hrtimer.c	hrtimers: Push pending hrtimers away from outgoing CPU earlier	2023-12-13 18:39:03 +01:00
itimer.c	…
jiffies.c	…
namespace.c	…
ntp.c	…
ntp_internal.h	…
posix-clock.c	…
posix-cpu-timers.c	posix-cpu-timers: Implement the missing timer_wait_running callback	2023-05-11 23:03:00 +09:00
posix-stubs.c	…
posix-timers.c	posix-timers: Prevent RT livelock in itimer_delete()	2023-07-19 16:20:59 +02:00
posix-timers.h	…
sched_clock.c	…
test_udelay.c	time/debug: Fix memory leak with using debugfs_lookup()	2023-03-10 09:33:52 +01:00
tick-broadcast-hrtimer.c	…
tick-broadcast.c	tick/broadcast: Make broadcast device replacement work correctly	2023-05-24 17:32:31 +01:00
tick-common.c	tick/common: Align tick period during sched_timer setup	2023-06-28 11:12:18 +02:00
tick-internal.h	…
tick-legacy.c	…
tick-oneshot.c	…
tick-sched.c	tick/rcu: Fix false positive "softirq work is pending" messages	2023-09-13 09:42:57 +02:00
tick-sched.h	…
time.c	…
time_test.c	…
timeconst.bc	…
timeconv.c	…
timecounter.c	…
timekeeping.c	timekeeping: Fix references to nonexistent ktime_get_fast_ns()	2023-05-11 23:03:35 +09:00
timekeeping.h	…
timekeeping_debug.c	…
timekeeping_internal.h	…
timer.c	…
timer_list.c	…
vsyscall.c	…