John Stultz 4eca11dbd2 timekeeping: Avoid taking lock in NMI path with CONFIG_DEBUG_TIMEKEEPING ...

commit 27727df240c7cc84f2ba6047c6f18d5addfd25ef upstream.

When I added some extra sanity checking in timekeeping_get_ns() under
CONFIG_DEBUG_TIMEKEEPING, I missed that the NMI safe __ktime_get_fast_ns()
method was using timekeeping_get_ns().

Thus the locking added to the debug checks broke the NMI-safety of
__ktime_get_fast_ns().

This patch open-codes the timekeeping_get_ns() logic for
__ktime_get_fast_ns(), so can avoid any deadlocks in NMI.

Fixes: 4ca22c2648f9 "timekeeping: Add warnings when overflows or underflows are observed"
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/1471993702-29148-2-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2016-09-15 08:27:52 +02:00

..

alarmtimer.c

…

clockevents.c

clockevents: Remove unused set_mode() callback

2015-09-14 11:00:55 +02:00

clocksource.c

clocksource: Allow unregistering the watchdog

2016-09-15 08:27:47 +02:00

hrtimer.c

hrtimer: Catch illegal clockids

2016-09-15 08:27:44 +02:00

itimer.c

itimers: Handle relative timers with CONFIG_TIME_LOW_RES proper

2016-02-25 12:01:25 -08:00

jiffies.c

…

Kconfig

rcu: Drop RCU_USER_QS in favor of NO_HZ_FULL

2015-07-06 13:52:18 -07:00

Makefile

…

ntp_internal.h

ntp/pps: use timespec64 for hardpps()

2015-10-01 09:57:59 -07:00

ntp.c

ntp: Fix ADJ_SETOFFSET being used w/ ADJ_NANO

2016-09-15 08:27:47 +02:00

posix-clock.c

posix-clock: Fix return code on the poll method's error path

2016-03-03 15:07:15 -08:00

posix-cpu-timers.c

posix_cpu_timer: Exit early when process has been reaped

2016-08-10 11:49:29 +02:00

posix-timers.c

posix-timers: Handle relative timers with CONFIG_TIME_LOW_RES proper

2016-02-25 12:01:25 -08:00

sched_clock.c

…

test_udelay.c

…

tick-broadcast-hrtimer.c

kernel: broadcast-hrtimer: Migrate to new 'set-state' interface

2015-08-10 11:41:08 +02:00

tick-broadcast.c

tick: Move the export of tick_broadcast_oneshot_control to the proper place

2015-07-14 12:01:04 +02:00

tick-common.c

clockevents: Remove unused set_mode() callback

2015-09-14 11:00:55 +02:00

tick-internal.h

…

tick-oneshot.c

…

tick-sched.c

tick/nohz: Set the correct expiry when switching to nohz/lowres mode

2016-03-03 15:07:26 -08:00

tick-sched.h

tick/broadcast: Make idle check independent from mode and config

2015-07-07 18:46:47 +02:00

time.c

Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2015-09-01 14:04:50 -07:00

timeconst.bc

timeconst: Update path in comment

2015-10-26 10:06:06 +09:00

timeconv.c

…

timecounter.c

…

timekeeping_debug.c

timekeeping: Cap array access in timekeeping_debug

2016-09-15 08:27:52 +02:00

timekeeping_internal.h

…

timekeeping.c

timekeeping: Avoid taking lock in NMI path with CONFIG_DEBUG_TIMEKEEPING

2016-09-15 08:27:52 +02:00

timekeeping.h

…

timer_list.c

hrtimer: Handle remaining time proper for TIME_LOW_RES

2016-02-17 12:30:57 -08:00

timer_stats.c

…

timer.c

timers: Use proper base migration in add_timer_on()

2015-11-04 20:23:19 +01:00