On 9/5/2025 8:43 AM, Praveen K Paladugu wrote:
>
>
> On 8/28/2025 7:43 PM, Nuno Das Neves wrote:
>> From: Purna Pavan Chandra Aekkaladevi <paekkalad...@linux.microsoft.com>
>>
>> Some newer hypervisor APIs are gated by feature bits in the so-called
>> "vmm capabilities" partition property. Store the capabilities on
> nit: s/xx/Some hypervisor APIs are gated by feature bits exposed in
> "vmm capabilities" partition property./g
Thanks, I'll update it for v2
Nuno
>> mshv_root module init, using HVCALL_GET_PARTITION_PROPERTY_EX.
>>>> Signed-off-by: Purna Pavan Chandra Aekkaladevi
>>>> <paekkalad...@linux.microsoft.com>
>> Signed-off-by: Nuno Das Neves <nunodasne...@linux.microsoft.com>
>> ---
>> drivers/hv/mshv_root.h | 1 +
>> drivers/hv/mshv_root_main.c | 28 ++++++++++++++++++++++++++++
>> 2 files changed, 29 insertions(+)
>>
>> diff --git a/drivers/hv/mshv_root.h b/drivers/hv/mshv_root.h
>> index 4aeb03bea6b6..0cb1e2589fe1 100644
>> --- a/drivers/hv/mshv_root.h
>> +++ b/drivers/hv/mshv_root.h
>> @@ -178,6 +178,7 @@ struct mshv_root {
>> struct hv_synic_pages __percpu *synic_pages;
>> spinlock_t pt_ht_lock;
>> DECLARE_HASHTABLE(pt_htable, MSHV_PARTITIONS_HASH_BITS);
>> + struct hv_partition_property_vmm_capabilities vmm_caps;
>> };
>> /*
>> diff --git a/drivers/hv/mshv_root_main.c b/drivers/hv/mshv_root_main.c
>> index 56ababab57ce..29f61ecc9771 100644
>> --- a/drivers/hv/mshv_root_main.c
>> +++ b/drivers/hv/mshv_root_main.c
>> @@ -2327,6 +2327,28 @@ static int __init mshv_root_partition_init(struct
>> device *dev)
>> return err;
>> }
>> +static int mshv_init_vmm_caps(struct device *dev)
>> +{
>> + int ret;
>> +
>> + memset(&mshv_root.vmm_caps, 0, sizeof(mshv_root.vmm_caps));
>> + ret = hv_call_get_partition_property_ex(HV_PARTITION_ID_SELF,
>> + HV_PARTITION_PROPERTY_VMM_CAPABILITIES,
>> + 0, &mshv_root.vmm_caps,
>> + sizeof(mshv_root.vmm_caps));
>> +
>> + /*
>> + * HV_PARTITION_PROPERTY_VMM_CAPABILITIES is not supported in
>> + * older hyperv. Ignore the -EIO error code.
>> + */
>> + if (ret && ret != -EIO)
>> + return ret;
>> +
>> + dev_dbg(dev, "vmm_caps=0x%llx\n", mshv_root.vmm_caps.as_uint64[0]);
>> +
>> + return 0;
>> +}
>> +
>> static int __init mshv_parent_partition_init(void)
>> {
>> int ret;
>> @@ -2377,6 +2399,12 @@ static int __init mshv_parent_partition_init(void)
>> if (ret)
>> goto remove_cpu_state;
>> + ret = mshv_init_vmm_caps(dev);
>> + if (ret) {
>> + dev_err(dev, "Failed to get VMM capabilities\n");
>> + goto exit_partition;
>> + }
>> +
>> ret = mshv_irqfd_wq_init();
>> if (ret)
>> goto exit_partition;
>
> Reviewed-by: Praveen K Paladugu <pra...@linux.microsoft.com>
