PARISC has a a busy looping power off routine. If the watchdog is enabled the watchdog timer will still fire, but the thread is not running, which causes the softlockup watchdog to trigger.
Provide a interface which allows to turn the watchdog off. Signed-off-by: Thomas Gleixner <t...@linutronix.de> Cc: Don Zickus <dzic...@redhat.com> Cc: Chris Metcalf <cmetc...@mellanox.com> Cc: linux-par...@vger.kernel.org Cc: Peter Zijlstra <pet...@infradead.org> Cc: Sebastian Siewior <bige...@linutronix.de> Cc: Nicholas Piggin <npig...@gmail.com> Cc: Ulrich Obergfell <uober...@redhat.com> Cc: Borislav Petkov <b...@alien8.de> Cc: Andrew Morton <a...@linux-foundation.org> Cc: Helge Deller <del...@gmx.de> Link: http://lkml.kernel.org/r/20170831073053.202164...@linutronix.de --- include/linux/nmi.h | 6 +++--- kernel/watchdog.c | 14 +++++++++++++- 2 files changed, 16 insertions(+), 4 deletions(-) --- a/include/linux/nmi.h +++ b/include/linux/nmi.h @@ -12,10 +12,10 @@ #ifdef CONFIG_LOCKUP_DETECTOR void lockup_detector_init(void); +void lockup_detector_soft_poweroff(void); #else -static inline void lockup_detector_init(void) -{ -} +static inline void lockup_detector_init(void) { } +static inline void lockup_detector_soft_poweroff(void) { } #endif #ifdef CONFIG_SOFTLOCKUP_DETECTOR --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -333,7 +333,8 @@ static enum hrtimer_restart watchdog_tim int duration; int softlockup_all_cpu_backtrace = sysctl_softlockup_all_cpu_backtrace; - if (atomic_read(&watchdog_park_in_progress) != 0) + if (!watchdog_enabled || + atomic_read(&watchdog_park_in_progress) != 0) return HRTIMER_NORESTART; /* kick the hardlockup detector */ @@ -660,6 +661,17 @@ static void set_sample_period(void) } #endif /* SOFTLOCKUP */ +/** + * lockup_detector_soft_poweroff - Interface to stop lockup detector(s) + * + * Special interface for parisc. It prevents lockup detector warnings from + * the default pm_poweroff() function which busy loops forever. + */ +void lockup_detector_soft_poweroff(void) +{ + watchdog_enabled = 0; +} + /* * Suspend the hard and soft lockup detector by parking the watchdog threads. */
