Vincent Guittot 15efb47dc5 PM-runtime: Fix deadlock with ktime_get() ... A deadlock has been seen when swicthing clocksources which use PM-runtime. The call path is: change_clocksource ... write_seqcount_begin ... timekeeping_update ... sh_cmt_clocksource_enable ... rpm_resume pm_runtime_mark_last_busy ktime_get do read_seqcount_begin while read_seqcount_retry .... write_seqcount_end Although we should be safe because we haven't yet changed the clocksource at that time, we can't do that because of seqcount protection. Use ktime_get_mono_fast_ns() instead which is lock safe for such cases. With ktime_get_mono_fast_ns, the timestamp is not guaranteed to be monotonic across an update and as a result can goes backward. According to update_fast_timekeeper() description: "In the worst case, this can result is a slightly wrong timestamp (a few nanoseconds)". For PM-runtime autosuspend, this means only that the suspend decision may be slightly suboptimal. Fixes: 8234f6734c ("PM-runtime: Switch autosuspend over to using hrtimers") Reported-by: Biju Das <biju.das@bp.renesas.com> Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>		2019-01-30 22:49:06 +01:00
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firmware_loader
power	PM-runtime: Fix deadlock with ktime_get()	2019-01-30 22:49:06 +01:00
regmap	regmap-irq: do not write mask register if mask_base is zero	2019-01-14 22:11:22 +00:00
test
arch_topology.c
attribute_container.c
base.h
bus.c
cacheinfo.c
class.c
component.c
container.c
core.c
cpu.c
dd.c
devcon.c
devcoredump.c
devres.c
devtmpfs.c
driver.c
firmware.c
hypervisor.c
init.c
isa.c
Kconfig
Makefile
map.c
memory.c
module.c
node.c
pinctrl.c
platform-msi.c
platform.c
property.c
soc.c
swnode.c
syscore.c
topology.c
transport_class.c