Re: [PATCH v3 2/8] KVM: arm64: Enable the KVM-VFIO device

From: Eric Auger
Date: Mon Dec 01 2014 - 09:57:11 EST


On 11/30/2014 01:14 PM, Christoffer Dall wrote:
> On Sun, Nov 23, 2014 at 07:35:54PM +0100, Eric Auger wrote:
>> Used by KVM-enabled VFIO-based device passthrough support in QEMU.
>>
>> Signed-off-by: Joel Schopp <joel.schopp@xxxxxxx>
>> Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx>
>>
>> ---
>>
>> Extracted from [RFC PATCH] arm64: KVM: add irqfd support
>> http://www.spinics.net/lists/kvm-arm/msg10798.html
>> ---
>> arch/arm64/kvm/Kconfig | 1 +
>> arch/arm64/kvm/Makefile | 2 +-
>> 2 files changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig
>> index 09c25c2..2edf926 100644
>> --- a/arch/arm64/kvm/Kconfig
>> +++ b/arch/arm64/kvm/Kconfig
>> @@ -26,6 +26,7 @@ config KVM
>> select KVM_ARM_HOST
>> select KVM_ARM_VGIC
>> select KVM_ARM_TIMER
>> + select KVM_VFIO
>> select HAVE_KVM_EVENTFD
>> ---help---
>> Support hosting virtualized guest machines.
>> diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile
>> index 2e6b827..81ed091 100644
>> --- a/arch/arm64/kvm/Makefile
>> +++ b/arch/arm64/kvm/Makefile
>> @@ -11,7 +11,7 @@ ARM=../../../arch/arm/kvm
>>
>> obj-$(CONFIG_KVM_ARM_HOST) += kvm.o
>>
>> -kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o
>> +kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o $(KVM)/vfio.o
>> kvm-$(CONFIG_KVM_ARM_HOST) += $(ARM)/arm.o $(ARM)/mmu.o $(ARM)/mmio.o
>> kvm-$(CONFIG_KVM_ARM_HOST) += $(ARM)/psci.o $(ARM)/perf.o
>>
>> --
>> 1.9.1
>>
>
> Should these patches not be squashed into one?
Yes I can do.
>
> Also, what do they enable at this point? Should they be queued by the
> end of the series instead?
Well to me this patch should be moved even outside of this series. The
KVM-VFIO device is loaded when the QEMU VFIO device is instantiated.
This is used to record the VFIO groups in use. In VFIO platform case, if
the KVM-VFIO device does not exist, this is not fatal but we get a
warning in QEMU.

The KVM-VFIO device however is mandatory to enable forwarded irq feature.

Best Regards

Eric
>
> -Christoffer
>

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/