To summarise the situation here:
* in ARMv8 the Generic Timers are mandatory at the architectural/hardware level
* however the kernel folks do not want to guarantee that they are always
exposed to userspace (they want the flexibility in future to disable the
userspace access for possible errat
On 25 July 2014 10:54, Riku Voipio wrote:
> On Tue, Jul 22, 2014 at 10:22:15PM -, Peter Maydell wrote:
>> On 22 July 2014 20:46, Richard Henderson wrote:
>> > On 07/21/2014 10:37 AM, Peter Maydell wrote:
>> >>> It's trying to measure clock cycles required to perform the startup
>> >>> relocat
On Tue, Jul 22, 2014 at 10:22:15PM -, Peter Maydell wrote:
> On 22 July 2014 20:46, Richard Henderson wrote:
> > On 07/21/2014 10:37 AM, Peter Maydell wrote:
> >>> It's trying to measure clock cycles required to perform the startup
> >>> relocations.
> >>
> >> That's a neat trick, given that t
On 07/22/2014 12:22 PM, Peter Maydell wrote:
> In any case the kernel guys say you can't guarantee they
> exist unless you get them to define an ELF hwcap for
> "timers exist and have a sane value in the 'what frequency
> are they' register". So this is a glibc bug and I'm
> not fixing QEMU...
The
On 22 July 2014 20:46, Richard Henderson wrote:
> On 07/21/2014 10:37 AM, Peter Maydell wrote:
>>> It's trying to measure clock cycles required to perform the startup
>>> relocations.
>>
>> That's a neat trick, given that the generic timers are not cycle
>> counters! They're a fixed frequency coun
On 07/21/2014 10:37 AM, Peter Maydell wrote:
>> It's trying to measure clock cycles required to perform the startup
>> relocations.
>
> That's a neat trick, given that the generic timers are not cycle
> counters! They're a fixed frequency counter which is generally
> unrelated and rather slower th
On 21 July 2014 20:00, Richard Henderson wrote:
> On 07/21/2014 12:46 AM, Peter Maydell wrote:
>> Q: is this in a released glibc? The generic timers are strictly speaking
>> optional, so this seems kind of bogus. Also looking at the glibc sources
>> it never reads the counter frequency so what it
On 07/21/2014 12:46 AM, Peter Maydell wrote:
> Q: is this in a released glibc? The generic timers are strictly speaking
> optional, so this seems kind of bogus. Also looking at the glibc sources
> it never reads the counter frequency so what it is hoping to do with the
> timer values I have no idea
The kernel folks tell me that the generic timers being userspace
accessible is only for the benefit of the kernel's VDSO, and they're not
part of the kernel-to-userspace contract. This is therefore a bug in
glibc, not QEMU, and we should get glibc fixed.
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You received this bug notification beca
Q: is this in a released glibc? The generic timers are strictly speaking
optional, so this seems kind of bogus. Also looking at the glibc sources
it never reads the counter frequency so what it is hoping to do with the
timer values I have no idea.
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You received this bug notification because you
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