can't enable sev_snp on Ubuntu22.04

[Cinderella0709]

Hi,

I'm new to confidential computing, and I want to test AMD sev_snp cooperating with Nvidia H100 to enable CC capability. However, I can't enable sev_snp by following the tutorial of sev-snp-devel branch. sev and sev-es are enabled, and I can launch a kvm by pass -object sev-guest. If I change the parameter into -object sev-snp-guest, I will get an error when launch kvm: qemu-system-x86_64: sev_kvm_init: failed to initialize ret=-25 fw_error=0 '' and qemu-system-x86_64: failed to initialize kvm: Operation not permitted.

my environment configuration is as follow:

[tlendacky]

The snp-latest branch is the branch that should be used from the AMDSEV repo.

I would recommend pulling the latest upstream Linux kernel or the kernel from the https://github.com/AMDESE/linux.git using the snp-host-latest branch.

Please try either one of those and report back if unable to enable SNP.