We have two race conditions in the probe code which could lead to a null
pointer dereference in the interrupt handler.
The interrupt handler accesses the clockevent device, which may not yet be
registered.
First race condition happens when the interrupt handler gets registered before
the interrupts get disabled. The second race condition happens when the
interrupts get enabled, but the clockevent device is not yet registered.
Fix that by disabling the interrupts before we register the interrupt and enable
the interrupts after the clockevent device got registered.
Reported-by: Gongbae Park <yongbae2@gmail.com>
Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
This patch adds a clock source and clock event for the timer found
on the Mediatek SoCs.
The Mediatek General Purpose Timer block provides five 32 bit timers and
one 64 bit timer.
Two 32 bit timers are used by this driver:
TIMER1: clock events supporting periodic and oneshot events
TIMER2: clock source configured as a free running counter
The General Purpose Timer block can be run with two clocks. A 13 MHz system
clock and the RTC clock running at 32 KHz. This implementation uses the system
clock with no clock source divider.
The interrupts are shared between the different timers and have to be read back
from a register. We just enable one interrupt for the clock event. The clock
event timer is used by all cores.
Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
