7285dd7fd3
Martin Schwidefsky analyzed it: To register a clocksource the clocksource_mutex is acquired and if necessary timekeeping_notify is called to install the clocksource as the timekeeper clock. timekeeping_notify uses stop_machine which needs to take cpu_add_remove_lock mutex. Starting a new cpu is done with the cpu_add_remove_lock mutex held. native_cpu_up checks the tsc of the new cpu and if the tsc is no good clocksource_change_rating is called. Which needs the clocksource_mutex and the deadlock is complete. The solution is to replace the TSC via the clocksource watchdog mechanism. Mark the TSC as unstable and schedule the watchdog work so it gets removed in the watchdog thread context. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> LKML-Reference: <new-submission> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: John Stultz <johnstul@us.ibm.com> |
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.. | ||
clockevents.c | ||
clocksource.c | ||
jiffies.c | ||
Kconfig | ||
Makefile | ||
ntp.c | ||
tick-broadcast.c | ||
tick-common.c | ||
tick-internal.h | ||
tick-oneshot.c | ||
tick-sched.c | ||
timecompare.c | ||
timekeeping.c | ||
timer_list.c | ||
timer_stats.c |