On Mon, Aug 10, 2026 at 12:45:00PM +0000, Wei Hu wrote: > From: Wei Liu <[email protected]> > > Query Hyper-V dynamic processor features during mshv initialization to
s/Hyper-V/MSHV/ > determine SEV-SNP availability, and report the result: on success log the > maximum number of encrypted partitions, otherwise log the decoded SNP > status string so misconfigurations are diagnosable. Cloud Hypervisor > expects the root driver to perform this capability check before SEV-SNP > child partition setup. No need to reference Cloud Hypervisor here. This applies to all VMMs. > > Signed-off-by: Wei Liu <[email protected]> > --- > drivers/hv/mshv_root_main.c | 96 +++++++++++++++++++++++++++++++++++++ > 1 file changed, 96 insertions(+) > [...] > +static void __init mshv_check_sev_snp_support(struct device *dev) > +{ > + struct hv_input_get_system_property *input; > + struct hv_output_get_system_property *output; > + unsigned long flags; > + enum hv_snp_status snp_status; > + u64 status; > + > + local_irq_save(flags); > + input = *this_cpu_ptr(hyperv_pcpu_input_arg); > + output = *this_cpu_ptr(hyperv_pcpu_output_arg); > + > + memset(input, 0, sizeof(*input)); > + input->property_id = HV_DYNAMIC_PROCESSOR_FEATURE_PROPERTY; > + input->hv_processor_feature = > HV_X64_DYNAMIC_PROCESSOR_FEATURE_SNP_STATUS; > + > + status = hv_do_hypercall(HVCALL_GET_SYSTEM_PROPERTY, input, output); > + local_irq_restore(flags); > + if (!hv_result_success(status)) { > + dev_warn(dev, "Failed to get SNP support: %s\n", > + hv_result_to_string(status)); > + return; > + } > + Our internal testing has shown that running this on an L1VH partition gets an error. The error should be non-fatal. Please squash my internal patch to this in the next revision. Wei
