Dexuan Cui 6986750cb5 tick/broadcast: Use for_each_cpu() specially on UP kernels ...

commit 5596fe34495cf0f645f417eb928ef224df3e3cb4 upstream.

for_each_cpu() unintuitively reports CPU0 as set independent of the actual
cpumask content on UP kernels. This causes an unexpected PIT interrupt
storm on a UP kernel running in an SMP virtual machine on Hyper-V, and as
a result, the virtual machine can suffer from a strange random delay of 1~20
minutes during boot-up, and sometimes it can hang forever.

Protect if by checking whether the cpumask is empty before entering the
for_each_cpu() loop.

[ tglx: Use !IS_ENABLED(CONFIG_SMP) instead of #ifdeffery ]

Signed-off-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Josh Poulson <jopoulso@microsoft.com>
Cc: "Michael Kelley (EOSG)" <Michael.H.Kelley@microsoft.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: stable@vger.kernel.org
Cc: Rakib Mullick <rakib.mullick@gmail.com>
Cc: Jork Loeser <Jork.Loeser@microsoft.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: KY Srinivasan <kys@microsoft.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Link: https://lkml.kernel.org/r/KL1P15301MB000678289FE55BA365B3279ABF990@KL1P15301MB0006.APCP153.PROD.OUTLOOK.COM
Link: https://lkml.kernel.org/r/KL1P15301MB0006FA63BC22BEB64902EAA0BF930@KL1P15301MB0006.APCP153.PROD.OUTLOOK.COM
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2018-05-22 18:54:00 +02:00

..

alarmtimer.c

alarmtimer: Init nanosleep alarm timer on stack

2018-04-26 11:02:21 +02:00

clockevents.c

clockevents: Make clockevents_config() static

2017-03-23 12:14:05 -07:00

clocksource.c

x86/tsc, sched/clock, clocksource: Use clocksource watchdog to provide stable sync points

2017-05-15 10:15:18 +02:00

hrtimer.c

hrtimer: Ensure POSIX compliance (relative CLOCK_REALTIME hrtimers)

2018-03-03 10:24:21 +01:00

itimer.c

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

jiffies.c

jiffies: Revert bogus conversion of NSEC_PER_SEC to TICK_NSEC

2017-03-07 11:03:28 +01:00

Kconfig

rcu: Remove nohz_full full-system-idle state machine

2017-06-08 18:52:39 -07:00

Makefile

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

ntp_internal.h

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

ntp.c

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

posix-clock.c

posix-timers: Move posix-timer internals to core

2017-06-04 15:40:23 +02:00

posix-cpu-timers.c

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

posix-stubs.c

posix-timers: Use get_timespec64() and put_timespec64()

2017-06-30 04:13:19 -04:00

posix-timers.c

posix-timers: Protect posix clock array access against speculation

2018-03-28 18:24:46 +02:00

posix-timers.h

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

sched_clock.c

timers, sched_clock: Update timeout for clock wrap

2017-03-23 12:30:27 -07:00

test_udelay.c

time: Avoid timespec in udelay_test

2016-06-20 12:47:26 -07:00

tick-broadcast-hrtimer.c

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

tick-broadcast.c

tick/broadcast: Use for_each_cpu() specially on UP kernels

2018-05-22 18:54:00 +02:00

tick-common.c

ktime: Cleanup ktime_set() usage

2016-12-25 17:21:22 +01:00

tick-internal.h

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

tick-oneshot.c

ktime: Get rid of the union

2016-12-25 17:21:22 +01:00

tick-sched.c

tick/sched: Do not mess with an enqueued hrtimer

2018-05-01 12:58:26 -07:00

tick-sched.h

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

time.c

time: introduce {get,put}_itimerspec64

2017-06-25 21:58:46 -04:00

timeconst.bc

time: Introduce jiffies64_to_nsecs()

2017-02-01 09:13:45 +01:00

timeconv.c

time: Add time64_to_tm()

2016-06-20 12:47:15 -07:00

timecounter.c

clocksource: Use a plain u64 instead of cycle_t

2016-12-25 11:04:12 +01:00

timekeeping_debug.c

PM / timekeeping: Print debug messages when requested

2017-07-23 00:03:43 +02:00

timekeeping_internal.h

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

timekeeping.c

drivers/pps: aesthetic tweaks to PPS-related content

2017-09-08 18:26:51 -07:00

timekeeping.h

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

timer_list.c

sysrq: Reset the watchdog timers while displaying high-resolution timers

2017-03-23 12:46:53 -07:00

timer.c

timers: Forward timer base before migrating timers

2018-03-08 22:41:04 -08:00