kvm-unit-tests gicv2 cases fail

kvm-unit-tests gicv2 cases fail

[Li Zhang]

Hi,

I run kvm-units-test on ARM server(QDF2400), but gicv2-ipi,
gicv2-active cases fail.
By debuging kvm-unit-tests source code, I found that interrupt is not
handled. do_handle_exception is not called.

By looking into KVM source code, it has GICv2 emulation on GICv3 support.
I've tried a lot of kernel versions, from v4.12~v4.19 in mainline,
these cases always fail.
Is it possible that hardware/software disables this?

It seems that GICv2 is a little old for ARM server, I am confused when
we can use it.
Do we need to care about these cases?

--

Best Regards
-Li

Re: kvm-unit-tests gicv2 cases fail

[Andrew Jones]

On Thu, Oct 18, 2018 at 05:17:57PM +0800, Li Zhang wrote:
> Hi,
> 
> I run kvm-units-test on ARM server(QDF2400), but gicv2-ipi,
> gicv2-active cases fail.
> By debuging kvm-unit-tests source code, I found that interrupt is not
> handled. do_handle_exception is not called.
> 
> By looking into KVM source code, it has GICv2 emulation on GICv3 support.
> I've tried a lot of kernel versions, from v4.12~v4.19 in mainline,
> these cases always fail.
> Is it possible that hardware/software disables this?
> 
> It seems that GICv2 is a little old for ARM server, I am confused when
> we can use it.
> Do we need to care about these cases?

We care, but I haven't seen these issues, and, if this only reproduces on
a gicv2 emulation on gicv3 configuration, then I don't have any hardware
where I can reproduce/debug it.

Thanks,
drew

Re: kvm-unit-tests gicv2 cases fail

[Li Zhang]

Yes, it only reproduces on a GICv2 emulation on GICv3.
I am looking into the source code. And I still can't find any error in
KVM code.
On Fri, Oct 19, 2018 at 11:26 AM Andrew Jones <drjones@redhat.com> wrote:
>
> On Thu, Oct 18, 2018 at 05:17:57PM +0800, Li Zhang wrote:
> > Hi,
> >
> > I run kvm-units-test on ARM server(QDF2400), but gicv2-ipi,
> > gicv2-active cases fail.
> > By debuging kvm-unit-tests source code, I found that interrupt is not
> > handled. do_handle_exception is not called.
> >
> > By looking into KVM source code, it has GICv2 emulation on GICv3 support.
> > I've tried a lot of kernel versions, from v4.12~v4.19 in mainline,
> > these cases always fail.
> > Is it possible that hardware/software disables this?
> >
> > It seems that GICv2 is a little old for ARM server, I am confused when
> > we can use it.
> > Do we need to care about these cases?
>
> We care, but I haven't seen these issues, and, if this only reproduces on
> a gicv2 emulation on gicv3 configuration, then I don't have any hardware
> where I can reproduce/debug it.
>
> Thanks,
> drew



-- 

Best Regards
-Li

Re: kvm-unit-tests gicv2 cases fail

[Ard Biesheuvel]

On 19 October 2018 at 11:25, Andrew Jones <drjones@redhat.com> wrote:
> On Thu, Oct 18, 2018 at 05:17:57PM +0800, Li Zhang wrote:
>> Hi,
>>
>> I run kvm-units-test on ARM server(QDF2400), but gicv2-ipi,
>> gicv2-active cases fail.
>> By debuging kvm-unit-tests source code, I found that interrupt is not
>> handled. do_handle_exception is not called.
>>
>> By looking into KVM source code, it has GICv2 emulation on GICv3 support.
>> I've tried a lot of kernel versions, from v4.12~v4.19 in mainline,
>> these cases always fail.
>> Is it possible that hardware/software disables this?
>>
>> It seems that GICv2 is a little old for ARM server, I am confused when
>> we can use it.
>> Do we need to care about these cases?
>
> We care, but I haven't seen these issues, and, if this only reproduces on
> a gicv2 emulation on gicv3 configuration, then I don't have any hardware
> where I can reproduce/debug it.
>

Do you have access to a Socionext SynQuacer board? I use it regularly
with QEMU/KVM running both in GICv2 and GICv3 modes, and I haven't
noticed any issues.

Re: kvm-unit-tests gicv2 cases fail

[Li Zhang]

On Fri, Oct 19, 2018 at 11:59 AM Ard Biesheuvel
<ard.biesheuvel@linaro.org> wrote:
>
> On 19 October 2018 at 11:25, Andrew Jones <drjones@redhat.com> wrote:
> > On Thu, Oct 18, 2018 at 05:17:57PM +0800, Li Zhang wrote:
> >> Hi,
> >>
> >> I run kvm-units-test on ARM server(QDF2400), but gicv2-ipi,
> >> gicv2-active cases fail.
> >> By debuging kvm-unit-tests source code, I found that interrupt is not
> >> handled. do_handle_exception is not called.
> >>
> >> By looking into KVM source code, it has GICv2 emulation on GICv3 support.
> >> I've tried a lot of kernel versions, from v4.12~v4.19 in mainline,
> >> these cases always fail.
> >> Is it possible that hardware/software disables this?
> >>
> >> It seems that GICv2 is a little old for ARM server, I am confused when
> >> we can use it.
> >> Do we need to care about these cases?
> >
> > We care, but I haven't seen these issues, and, if this only reproduces on
> > a gicv2 emulation on gicv3 configuration, then I don't have any hardware
> > where I can reproduce/debug it.
> >
>
> Do you have access to a Socionext SynQuacer board? I use it regularly
> with QEMU/KVM running both in GICv2 and GICv3 modes, and I haven't
> noticed any issues.

I only have QDF2400 boards on my hand.

Do you mean by starting a guest with QEMU/KVM with GICv2?
I tried that once, guest hang. Guest kernel has some message with call trace.
So I checked kvm-unit-tests, GICv2 always failed.


-- 

Best Regards
-Li

Re: kvm-unit-tests gicv2 cases fail

[Christoffer Dall]

On Thu, Oct 18, 2018 at 05:17:57PM +0800, Li Zhang wrote:
> Hi,
> 
> I run kvm-units-test on ARM server(QDF2400), but gicv2-ipi,
> gicv2-active cases fail.

I didn't think QDF2400 has GICv2 on GICv3 support?

Do the test cases fail or are they reported as skipped?

> By debuging kvm-unit-tests source code, I found that interrupt is not
> handled. do_handle_exception is not called.
> 
> By looking into KVM source code, it has GICv2 emulation on GICv3 support.
> I've tried a lot of kernel versions, from v4.12~v4.19 in mainline,
> these cases always fail.
> Is it possible that hardware/software disables this?
> 
> It seems that GICv2 is a little old for ARM server, I am confused when
> we can use it.
> Do we need to care about these cases?
> 

I don't think you need to care.  I believe Marc has run the
GICv2-on-GICv3 tests on his supported platforms with recent
kvm-unit-tests and other have reported succes as well.


Thanks,

    Christoffer

Re: kvm-unit-tests gicv2 cases fail

[Marc Zyngier]

[Thanks Christoffer for cc'ing me]

On Thu, 01 Nov 2018 10:10:48 +0000,
Christoffer Dall <christoffer.dall@arm.com> wrote:
> 
> On Thu, Oct 18, 2018 at 05:17:57PM +0800, Li Zhang wrote:
> > Hi,
> > 
> > I run kvm-units-test on ARM server(QDF2400), but gicv2-ipi,
> > gicv2-active cases fail.
> 
> I didn't think QDF2400 has GICv2 on GICv3 support?
> 
> Do the test cases fail or are they reported as skipped?
> 
> > By debuging kvm-unit-tests source code, I found that interrupt is not
> > handled. do_handle_exception is not called.
> > 
> > By looking into KVM source code, it has GICv2 emulation on GICv3 support.
> > I've tried a lot of kernel versions, from v4.12~v4.19 in mainline,
> > these cases always fail.
> > Is it possible that hardware/software disables this?

Most implementations do not have the v2 compatibility interface, and
nobody really needs it. This is a convenient way to run older VMs that
do not know about GICv3 (32bit VMs, for example), but that's in no way
a common setup.

> > 
> > It seems that GICv2 is a little old for ARM server, I am confused when
> > we can use it.
> > Do we need to care about these cases?
> > 
> 
> I don't think you need to care.  I believe Marc has run the
> GICv2-on-GICv3 tests on his supported platforms with recent
> kvm-unit-tests and other have reported succes as well.

Here you go (on my Chromebook running 4.18):

PASS gicv2-ipi (3 tests)
PASS gicv2-mmio (17 tests)
PASS gicv2-mmio-up (17 tests)
PASS gicv2-mmio-3p (17 tests)
PASS gicv3-ipi (3 tests)
PASS gicv2-active (1 tests)
PASS gicv3-active (1 tests)

Thanks,

	M.

-- 
Jazz is not dead, it just smell funny.

Re: kvm-unit-tests gicv2 cases fail

[Li Zhang]

On Thu, Nov 1, 2018 at 6:25 PM Marc Zyngier <marc.zyngier@arm.com> wrote:
>
> [Thanks Christoffer for cc'ing me]
>
> On Thu, 01 Nov 2018 10:10:48 +0000,
> Christoffer Dall <christoffer.dall@arm.com> wrote:
> >
> > On Thu, Oct 18, 2018 at 05:17:57PM +0800, Li Zhang wrote:
> > > Hi,
> > >
> > > I run kvm-units-test on ARM server(QDF2400), but gicv2-ipi,
> > > gicv2-active cases fail.
> >
> > I didn't think QDF2400 has GICv2 on GICv3 support?
> >
> > Do the test cases fail or are they reported as skipped?
> >
> > > By debuging kvm-unit-tests source code, I found that interrupt is not
> > > handled. do_handle_exception is not called.
> > >
> > > By looking into KVM source code, it has GICv2 emulation on GICv3 support.
> > > I've tried a lot of kernel versions, from v4.12~v4.19 in mainline,
> > > these cases always fail.
> > > Is it possible that hardware/software disables this?
>
> Most implementations do not have the v2 compatibility interface, and
> nobody really needs it. This is a convenient way to run older VMs that
> do not know about GICv3 (32bit VMs, for example), but that's in no way
> a common setup.

I see, thanks for your explanation.

>
> > >
> > > It seems that GICv2 is a little old for ARM server, I am confused when
> > > we can use it.
> > > Do we need to care about these cases?
> > >
> >
> > I don't think you need to care.  I believe Marc has run the
> > GICv2-on-GICv3 tests on his supported platforms with recent
> > kvm-unit-tests and other have reported succes as well.
>
> Here you go (on my Chromebook running 4.18):
>
> PASS gicv2-ipi (3 tests)
> PASS gicv2-mmio (17 tests)
> PASS gicv2-mmio-up (17 tests)
> PASS gicv2-mmio-3p (17 tests)
> PASS gicv3-ipi (3 tests)
> PASS gicv2-active (1 tests)
> PASS gicv3-active (1 tests)
>
> Thanks,
>
>         M.
>
> --
> Jazz is not dead, it just smell funny.



-- 

Best Regards
-Li