Re: [RFC v2 01/24] linux-headers: Add RME related definitions

On 7/30/26 3:41 PM, Kohei Enju wrote:
> On 07/28 13:26, Mathieu Poirier wrote:
>> From: Jean-Philippe Brucker <[email protected]>
>>
>> This is a temporary patch intended for testing purposes only. It provides
>> definitions related to supporting Realms by the QEMU-VMM.
>>
>> Signed-off-by: Jean-Philippe Brucker <[email protected]>
>> Signed-off-by: Mathieu Poirier <[email protected]>
>> ---
>>   linux-headers/asm-arm64/kvm.h |  9 +++++++++
>>   linux-headers/linux/kvm.h     | 10 +++++++++-
>>   2 files changed, 18 insertions(+), 1 deletion(-)
>>
>> diff --git a/linux-headers/asm-arm64/kvm.h b/linux-headers/asm-arm64/kvm.h
>> index 6aefe7973814..4c08631ec7d2 100644
>> --- a/linux-headers/asm-arm64/kvm.h
>> +++ b/linux-headers/asm-arm64/kvm.h
>> @@ -208,6 +208,15 @@ struct kvm_arm_counter_offset {
>>   	__u64 reserved;
>>   };
>>   
>> +#define KVM_ARM_RMI_POPULATE_FLAGS_MEASURE     (1 << 0)
>> +struct kvm_arm_rmi_populate {
>> +	__u64 base;
>> +	__u64 size;
>> +	__u64 source_uaddr;
>> +	__u32 flags;
>> +	__u32 reserved;
>> +};
>> +
>>   #define KVM_ARM_TAGS_TO_GUEST		0
>>   #define KVM_ARM_TAGS_FROM_GUEST		1
>>   
>> diff --git a/linux-headers/linux/kvm.h b/linux-headers/linux/kvm.h
>> index dd52e2a65bfd..cdd5ad11f85a 100644
>> --- a/linux-headers/linux/kvm.h
>> +++ b/linux-headers/linux/kvm.h
>> @@ -689,14 +689,19 @@ struct kvm_enable_cap {
>>    * address size for the VM. Bits[7-0] are reserved for the guest
>>    * PA size shift (i.e, log2(PA_Size)). For backward compatibility,
>>    * value 0 implies the default IPA size, 40bits.
>> + *
>> + * Bits[30-31] are reserved for the VM type
>>    */
>>   #define KVM_VM_TYPE_ARM_IPA_SIZE_MASK	0xffULL
>>   #define KVM_VM_TYPE_ARM_IPA_SIZE(x)		\
>>   	((x) & KVM_VM_TYPE_ARM_IPA_SIZE_MASK)
>>   
>> +#define KVM_VM_TYPE_ARM_NORMAL		0
>> +#define KVM_VM_TYPE_ARM_REALM		(1UL << 30)
>>   #define KVM_VM_TYPE_ARM_PROTECTED	(1UL << 31)
>>   #define KVM_VM_TYPE_ARM_MASK		(KVM_VM_TYPE_ARM_IPA_SIZE_MASK | \
>> -					 KVM_VM_TYPE_ARM_PROTECTED)
>> +					 KVM_VM_TYPE_ARM_PROTECTED | \
>> +					 KVM_VM_TYPE_ARM_REALM)
>>   
>>   /*
>>    * ioctls for /dev/kvm fds:
>> @@ -719,6 +724,8 @@ struct kvm_enable_cap {
>>   #define KVM_GET_EMULATED_CPUID	  _IOWR(KVMIO, 0x09, struct kvm_cpuid2)
>>   #define KVM_GET_MSR_FEATURE_INDEX_LIST    _IOWR(KVMIO, 0x0a, struct kvm_msr_list)
>>   
>> +#define KVM_ARM_RMI_POPULATE	  _IOWR(KVMIO, 0xd7, struct kvm_arm_rmi_populate)
>> +
>>   /*
>>    * Extension capability list.
>>    */
>> @@ -986,6 +993,7 @@ struct kvm_enable_cap {
>>   #define KVM_CAP_S390_KEYOP 247
>>   #define KVM_CAP_S390_VSIE_ESAMODE 248
>>   #define KVM_CAP_S390_HPAGE_2G 249
>> +#define KVM_CAP_ARM_RMI 250
> 
> Not a big deal, but a note for anyone testing this series:
> 
> Use Linaro's Linux kernel tree, as mentioned in the cover letter:
> https://gitlab.com/Linaro/cca-public/linux/-/tree/upstream-v2?ref_type=heads
> 

It seems the capability values get an extra leap on KVM_CAP_ARM_AMI in
"upstream-v2" host kernel.

   include/uapi/linux/kvm.h

   #define KVM_CAP_S390_KEYOP 247
   #define KVM_CAP_S390_VSIE_ESAMODE 248
   #define KVM_CAP_ARM_RMI 250

> Alternetively, if you're using Arm's tree or other trees with Steven
> Price's v14 series as I am:
> 
> You'll need to adjust the definition of KVM_CAP_ARM_RMI, since it uses a
> differenct capability number.
> 
>>   
>>   struct kvm_irq_routing_irqchip {
>>   	__u32 irqchip;
>> -- 
>> 2.43.0
>>

Thanks,
Gavin