[PATCH] ARM/ARM64: arch-timer: fix arch_timer_probed logic

[Thomas Gleixner]

On Mon, 27 Oct 2014, Marc Zyngier wrote:
> Hi Daniel,
> 
> On 21/10/14 12:12, Daniel Lezcano wrote:
> > On 10/21/2014 01:07 PM, Mark Rutland wrote:
> >> Hi Daniel,
> >>
> >> On Tue, Oct 21, 2014 at 11:58:29AM +0100, Daniel Lezcano wrote:
> >>> On 10/15/2014 05:06 PM, Marc Zyngier wrote:
> >>>> Commit c387f07e6205 (clocksource: arm_arch_timer: Discard unavailable
> >>>> timers correctly) changed the way the driver makes sure both the memory
> >>>> and system-register timers have been probed before finalizing the probing.
> >>>>
> >>>> There is a interesting flaw in this logic that leads to this final step
> >>>> never to be executed. Things seems to work pretty well until something
> >>>> actually needs the data that is produced during this final stage.
> >>>>
> >>>> For example, KVM explodes on the first run of a guest when executed on
> >>>> a platform that has both memory and sysreg nodes (Juno, for example).
> >>>>
> >>>> Just fix the damned logic, and enjoy booting VMs again.
> >>>>
> >>>> Tested on a Juno system.
> >>>>
> >>>> Cc: Sudeep Holla <sudeep.holla at arm.com>
> >>>> Cc: Stephen Boyd <sboyd at codeaurora.org>
> >>>> Cc: Mark Rutland <mark.rutland at arm.com>
> >>>> Cc: Daniel Lezcano <daniel.lezcano at linaro.org>
> >>>> Cc: Christoffer Dall <christoffer.dall at linaro.org>
> >>>> Reported-by: Riku Voipio <riku.voipio at linaro.org>
> >>>> Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
> >>>> ---
> >>>
> >>> Applied to my tree. Also for -next.
> >>
> >> Is this going to hit -rc2? This was a regression introduced in -rc1.
> >>
> >> Without this fix we've also lost our high precision sched_clock on arm64
> >> platforms.
> >>
> > 
> > Sure.
> > 
> > Thomas or Ingo,
> > 
> > is it possible to update the tip/urgent branch, so I can send the fixes 
> > against 3.18-rc1 ?
> 
> Any update on this? -rc2 has landed, but arm/arm64 timers are still in a
> rather bad shape. Can this please be merged as an urgent fix?

Daniel, timers/urgent is on rc1 already. Please send your pull request.

Thanks,

	tglx