Question regarding QEMU

[Sabanic-P]

Hello,

I am trying to use the igvm branch of QEMU for SVSM and regular AMD SEV-SNP virtual machines. SVSM works fine with the igvm file. But with regular CVM without igvm:

  sudo {{QEMU_COCONUT}} \
        -cpu EPYC-v4,host-phys-bits=true \
        -smp {{smp}} \
        -m {{mem}} \
        -machine q35,confidential-guest-support=sev0,memory-backend=ram1 \
        -object memory-backend-memfd,id=ram1,size={{mem}},share=true,prealloc=false \
        -object sev-snp-guest,id=sev0,cbitpos=51,reduced-phys-bits=1 \
        -enable-kvm \
        -nographic \
        -kernel {{LINUX_DIR}}/arch/x86/boot/bzImage \
        -append "root=/dev/vda console=hvc0" \
        -blockdev qcow2,node-name=q2,file.driver=file,file.filename={{GUEST_FS}} \
        -device virtio-blk-pci,drive=q2 \
        -drive if=pflash,format=raw,unit=0,file={{OVMF_COCONUT}},readonly=on \
        -serial null \

Qemu only returns with:

qemu-system-x86_64: Failed to put registers after init: Invalid argument

I was wondering if it is possible to boot this version of Qemu without SVMS?

[roy-hopkins]

I've just tried this myself and it I get the same results - SEV-SNP without SVSM does not seem to work. I'll investigate a bit further.