Re: [RFC PATCH 8/8] ARM: KVM: Support vGICv3 ITS

[Vladimir Murzin <vladimir.murzin@arm.com>]

On 21/10/16 12:02, Andre Przywara wrote:
> Hi,
> 
> On 21/10/16 10:36, Vladimir Murzin wrote:
>> This patch allows to build and use vGICv3 ITS in 32-bit mode.
> 
> Ah, what a relief to see that config option go. Thanks for that!
> 
> I quickly booted an ITS guest on a (64-bit) model and couldn't spot any
> regressions.

Awesome!

> 
>> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
> 
> Reviewed-by: Andre Przywara <andre.przywara@arm.com>

Thanks for your time!

Cheers
Vladimir

> 
> Cheers,
> Andre.
> 
>> ---
>>  Documentation/virtual/kvm/api.txt   |    2 +-
>>  arch/arm/include/uapi/asm/kvm.h     |    2 ++
>>  arch/arm/kvm/Kconfig                |    1 +
>>  arch/arm/kvm/Makefile               |    1 +
>>  arch/arm/kvm/arm.c                  |    6 ++++++
>>  arch/arm64/kvm/Kconfig              |    4 ----
>>  arch/arm64/kvm/reset.c              |    6 ------
>>  virt/kvm/arm/vgic/vgic-kvm-device.c |    2 --
>>  virt/kvm/arm/vgic/vgic-mmio-v3.c    |    2 --
>>  virt/kvm/arm/vgic/vgic.h            |   26 --------------------------
>>  10 files changed, 11 insertions(+), 41 deletions(-)
>>
>> diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
>> index 739db9a..2feeae6 100644
>> --- a/Documentation/virtual/kvm/api.txt
>> +++ b/Documentation/virtual/kvm/api.txt
>> @@ -2198,7 +2198,7 @@ after pausing the vcpu, but before it is resumed.
>>  4.71 KVM_SIGNAL_MSI
>>  
>>  Capability: KVM_CAP_SIGNAL_MSI
>> -Architectures: x86 arm64
>> +Architectures: x86 arm arm64
>>  Type: vm ioctl
>>  Parameters: struct kvm_msi (in)
>>  Returns: >0 on delivery, 0 if guest blocked the MSI, and -1 on error
>> diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h
>> index b38c10c..af05f8e 100644
>> --- a/arch/arm/include/uapi/asm/kvm.h
>> +++ b/arch/arm/include/uapi/asm/kvm.h
>> @@ -87,9 +87,11 @@ struct kvm_regs {
>>  /* Supported VGICv3 address types  */
>>  #define KVM_VGIC_V3_ADDR_TYPE_DIST	2
>>  #define KVM_VGIC_V3_ADDR_TYPE_REDIST	3
>> +#define KVM_VGIC_ITS_ADDR_TYPE		4
>>  
>>  #define KVM_VGIC_V3_DIST_SIZE		SZ_64K
>>  #define KVM_VGIC_V3_REDIST_SIZE		(2 * SZ_64K)
>> +#define KVM_VGIC_V3_ITS_SIZE		(2 * SZ_64K)
>>  
>>  #define KVM_ARM_VCPU_POWER_OFF		0 /* CPU is started in OFF state */
>>  #define KVM_ARM_VCPU_PSCI_0_2		1 /* CPU uses PSCI v0.2 */
>> diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig
>> index 3e1cd04..90d0176 100644
>> --- a/arch/arm/kvm/Kconfig
>> +++ b/arch/arm/kvm/Kconfig
>> @@ -34,6 +34,7 @@ config KVM
>>  	select HAVE_KVM_IRQFD
>>  	select HAVE_KVM_IRQCHIP
>>  	select HAVE_KVM_IRQ_ROUTING
>> +	select HAVE_KVM_MSI
>>  	depends on ARM_VIRT_EXT && ARM_LPAE && ARM_ARCH_TIMER
>>  	---help---
>>  	  Support hosting virtualized guest machines.
>> diff --git a/arch/arm/kvm/Makefile b/arch/arm/kvm/Makefile
>> index f19842e..d571243 100644
>> --- a/arch/arm/kvm/Makefile
>> +++ b/arch/arm/kvm/Makefile
>> @@ -32,5 +32,6 @@ obj-y += $(KVM)/arm/vgic/vgic-mmio.o
>>  obj-y += $(KVM)/arm/vgic/vgic-mmio-v2.o
>>  obj-y += $(KVM)/arm/vgic/vgic-mmio-v3.o
>>  obj-y += $(KVM)/arm/vgic/vgic-kvm-device.o
>> +obj-y += $(KVM)/arm/vgic/vgic-its.o
>>  obj-y += $(KVM)/irqchip.o
>>  obj-y += $(KVM)/arm/arch_timer.o
>> diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
>> index 03e9273..8b13448 100644
>> --- a/arch/arm/kvm/arm.c
>> +++ b/arch/arm/kvm/arm.c
>> @@ -209,6 +209,12 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
>>  	case KVM_CAP_MAX_VCPUS:
>>  		r = KVM_MAX_VCPUS;
>>  		break;
>> +	case KVM_CAP_MSI_DEVID:
>> +		if (!kvm)
>> +			r = -EINVAL;
>> +		else
>> +			r = kvm->arch.vgic.msis_require_devid;
>> +		break;
>>  	default:
>>  		r = kvm_arch_dev_ioctl_check_extension(kvm, ext);
>>  		break;
>> diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig
>> index 6eaf12c..52cb7ad 100644
>> --- a/arch/arm64/kvm/Kconfig
>> +++ b/arch/arm64/kvm/Kconfig
>> @@ -16,9 +16,6 @@ menuconfig VIRTUALIZATION
>>  
>>  if VIRTUALIZATION
>>  
>> -config KVM_ARM_VGIC_V3_ITS
>> -	bool
>> -
>>  config KVM
>>  	bool "Kernel-based Virtual Machine (KVM) support"
>>  	depends on OF
>> @@ -34,7 +31,6 @@ config KVM
>>  	select KVM_VFIO
>>  	select HAVE_KVM_EVENTFD
>>  	select HAVE_KVM_IRQFD
>> -	select KVM_ARM_VGIC_V3_ITS
>>  	select KVM_ARM_PMU if HW_PERF_EVENTS
>>  	select HAVE_KVM_MSI
>>  	select HAVE_KVM_IRQCHIP
>> diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c
>> index 5bc4608..e95d4f6 100644
>> --- a/arch/arm64/kvm/reset.c
>> +++ b/arch/arm64/kvm/reset.c
>> @@ -86,12 +86,6 @@ int kvm_arch_dev_ioctl_check_extension(struct kvm *kvm, long ext)
>>  	case KVM_CAP_VCPU_ATTRIBUTES:
>>  		r = 1;
>>  		break;
>> -	case KVM_CAP_MSI_DEVID:
>> -		if (!kvm)
>> -			r = -EINVAL;
>> -		else
>> -			r = kvm->arch.vgic.msis_require_devid;
>> -		break;
>>  	default:
>>  		r = 0;
>>  	}
>> diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c
>> index ce1f4ed..fbe87a6 100644
>> --- a/virt/kvm/arm/vgic/vgic-kvm-device.c
>> +++ b/virt/kvm/arm/vgic/vgic-kvm-device.c
>> @@ -221,11 +221,9 @@ int kvm_register_vgic_device(unsigned long type)
>>  		ret = kvm_register_device_ops(&kvm_arm_vgic_v3_ops,
>>  					      KVM_DEV_TYPE_ARM_VGIC_V3);
>>  
>> -#ifdef CONFIG_KVM_ARM_VGIC_V3_ITS
>>  		if (ret)
>>  			break;
>>  		ret = kvm_vgic_register_its_device();
>> -#endif
>>  		break;
>>  	}
>>  
>> diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
>> index 0d3c76a..50f42f0 100644
>> --- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
>> +++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
>> @@ -42,7 +42,6 @@ u64 update_64bit_reg(u64 reg, unsigned int offset, unsigned int len,
>>  	return reg | ((u64)val << lower);
>>  }
>>  
>> -#ifdef CONFIG_KVM_ARM_VGIC_V3_ITS
>>  bool vgic_has_its(struct kvm *kvm)
>>  {
>>  	struct vgic_dist *dist = &kvm->arch.vgic;
>> @@ -52,7 +51,6 @@ bool vgic_has_its(struct kvm *kvm)
>>  
>>  	return dist->has_its;
>>  }
>> -#endif
>>  
>>  static unsigned long vgic_mmio_read_v3_misc(struct kvm_vcpu *vcpu,
>>  					    gpa_t addr, unsigned int len)
>> diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
>> index 9d9e014..859f65c 100644
>> --- a/virt/kvm/arm/vgic/vgic.h
>> +++ b/virt/kvm/arm/vgic/vgic.h
>> @@ -84,37 +84,11 @@ static inline void vgic_get_irq_kref(struct vgic_irq *irq)
>>  int vgic_v3_map_resources(struct kvm *kvm);
>>  int vgic_register_redist_iodevs(struct kvm *kvm, gpa_t dist_base_address);
>>  
>> -#ifdef CONFIG_KVM_ARM_VGIC_V3_ITS
>>  int vgic_register_its_iodevs(struct kvm *kvm);
>>  bool vgic_has_its(struct kvm *kvm);
>>  int kvm_vgic_register_its_device(void);
>>  void vgic_enable_lpis(struct kvm_vcpu *vcpu);
>>  int vgic_its_inject_msi(struct kvm *kvm, struct kvm_msi *msi);
>> -#else
>> -static inline int vgic_register_its_iodevs(struct kvm *kvm)
>> -{
>> -	return -ENODEV;
>> -}
>> -
>> -static inline bool vgic_has_its(struct kvm *kvm)
>> -{
>> -	return false;
>> -}
>> -
>> -static inline int kvm_vgic_register_its_device(void)
>> -{
>> -	return -ENODEV;
>> -}
>> -
>> -static inline void vgic_enable_lpis(struct kvm_vcpu *vcpu)
>> -{
>> -}
>> -
>> -static inline int vgic_its_inject_msi(struct kvm *kvm, struct kvm_msi *msi)
>> -{
>> -	return -ENODEV;
>> -}
>> -#endif
>>  
>>  int kvm_register_vgic_device(unsigned long type);
>>  int vgic_lazy_init(struct kvm *kvm);
>>
>