Messages in this thread Patch in this message | | | Date | Thu, 15 Dec 2016 03:16:10 -0800 | From | tip-bot for Thomas Gleixner <> | Subject | [tip:smp/urgent] clocksource/dummy_timer: Move hotplug callback after the real timers |
| |
Commit-ID: 9bf11ecce5a2758e5a097c2f3a13d08552d0d6f9 Gitweb: http://git.kernel.org/tip/9bf11ecce5a2758e5a097c2f3a13d08552d0d6f9 Author: Thomas Gleixner <tglx@linutronix.de> AuthorDate: Thu, 15 Dec 2016 12:01:05 +0100 Committer: Thomas Gleixner <tglx@linutronix.de> CommitDate: Thu, 15 Dec 2016 12:09:20 +0100
clocksource/dummy_timer: Move hotplug callback after the real timers
When the dummy timer callback is invoked before the real timer callbacks, then it tries to install that timer for the starting CPU. If the platform does not have a broadcast timer installed the installation fails with a kernel crash. The crash happens due to a unconditional deference of the non available broadcast device. This needs to be fixed in the timer core code.
But even when this is fixed in the core code then installing the dummy timer before the real timers is a pointless exercise.
Move it to the end of the callback list.
Fixes: 00c1d17aab51 ("clocksource/dummy_timer: Convert to hotplug state machine") Reported-and-tested-by: Mason <slash.tmp@free.fr> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Richard Cochran <rcochran@linutronix.de> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org>, Cc: Sebastian Frias <sf84@laposte.net> Cc: Thibaud Cornic <thibaud_cornic@sigmadesigns.com> Cc: Robin Murphy <robin.murphy@arm.com> Link: http://lkml.kernel.org/r/1147ef90-7877-e4d2-bb2b-5c4fa8d3144b@free.fr --- include/linux/cpuhotplug.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index 22acee7..2ab7bf5 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -101,7 +101,6 @@ enum cpuhp_state { CPUHP_AP_ARM_L2X0_STARTING, CPUHP_AP_ARM_ARCH_TIMER_STARTING, CPUHP_AP_ARM_GLOBAL_TIMER_STARTING, - CPUHP_AP_DUMMY_TIMER_STARTING, CPUHP_AP_JCORE_TIMER_STARTING, CPUHP_AP_EXYNOS4_MCT_TIMER_STARTING, CPUHP_AP_ARM_TWD_STARTING, @@ -115,6 +114,8 @@ enum cpuhp_state { CPUHP_AP_KVM_ARM_VGIC_INIT_STARTING, CPUHP_AP_KVM_ARM_VGIC_STARTING, CPUHP_AP_KVM_ARM_TIMER_STARTING, + /* Must be the last timer callback */ + CPUHP_AP_DUMMY_TIMER_STARTING, CPUHP_AP_ARM_XEN_STARTING, CPUHP_AP_ARM_CORESIGHT_STARTING, CPUHP_AP_ARM_CORESIGHT4_STARTING,
| |