[PATCH 0/3] Support userspace irqchip with arch timers

[Alexander Graf]

> Am 28.10.2016 um 16:38 schrieb Marc Zyngier <marc.zyngier at arm.com>:
> 
> Alex,
> 
>> On 30/09/16 20:31, Alexander Graf wrote:
>> 
>> 
>>> On 30.09.16 17:43, Christoffer Dall wrote:
>>>> On Fri, Sep 30, 2016 at 05:38:11PM +0200, Alexander Graf wrote:
>>>> 
>>>> 
>>>>> On 30.09.16 16:54, Alexander Graf wrote:
>>>>> 
>>>>> 
>>>>>> On 27.09.16 21:08, Christoffer Dall wrote:
>>>>>> Hi Alex,
>>>>>> 
>>>>>> Marc and I have been looking at this during Linaro connect and have
>>>>>> slightly reworked your patch into this small series.
>>>>>> 
>>>>>> It would be good if you could have a look at it and test it out.
>>>>>> 
>>>>>> I've tested it with your QEMU, and it works for UP, but secondary CPUs
>>>>>> fail to come up, and it looks like the kernel never gets an IPI for
>>>>>> those CPUs from userspace.  Any chance you're willing to take a look at
>>>>>> that?
>>>>> 
>>>>> I still need to see whether I can come up with a prettier solution, but
>>>>> for now this works:
>>>>> 
>>>>> diff --git a/target-i386/kvm.c b/target-i386/kvm.c
>>>> 
>>>> Eh, no, not in i386 code :). But the problem seems to be a missing
>>>> mpstate sync.
>>>> 
>>> Yeah, that looked really dodgy.  Have you tested it? :)
>> 
>> This time around tested with the correct command line parameters I hope
>> :). I'll send a pretty patch later.
>> 
>> diff --git a/target-arm/kvm.c b/target-arm/kvm.c
>> index b4c8fe2..b549f00 100644
>> --- a/target-arm/kvm.c
>> +++ b/target-arm/kvm.c
>> @@ -173,6 +173,12 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
>>      */
>>     kvm_async_interrupts_allowed = true;
>> 
>> +    /*
>> +     * PSCI wakes up secondary cores, so we always need to
>> +     * have vCPUs waiting in kernel space
>> +     */
>> +    kvm_halt_in_kernel_allowed = true;
>> +
>>     cap_has_mp_state = kvm_check_extension(s, KVM_CAP_MP_STATE);
>> 
>>     type_register_static(&host_arm_cpu_type_info);
> 
> What the status of userspace for this thing? Are QEMU patches being
> posted and reviewed?

I didn't see a notification that the patches were merged. Are they in Linus' tree yet? Then I can post enablement to qemu-devel.

Alex