Re: [PATCH 00/20] OvmfPkg: SEV: decrypt the initial SMRAM save state map for SMBASE relocation

[Laszlo Ersek <lersek@redhat.com>]

On 03/02/18 14:17, Brijesh Singh wrote:
> On 3/2/18 5:53 AM, Laszlo Ersek wrote:

>> Do you have (maybe updated) instructions for setting up the SEV host?
>> What are the latest bits that are expected to work together?

> For host kernel:
> - use recent kvm/master
> - make sure following kernel config is enabled
>   CONFIG_KVM_AMD_SEV
>   CONFIG_CRYPTO_DEV_SP_PSP
>   CONFIG_AMD_MEM_ENCRYPT
>   CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
> 
> For guest kernel:
>  - you can use host kernel or anything >=4.15
>     make sure you have following config enabled in kernel:
>       CONFIG_AMD_MEM_ENCRYPT
> 
> For qemu:
> - v10 patches from this branch
> https://github.com/codomania/qemu/tree/v10

QEMU exits with the following error for me:

2018-03-05T13:40:12.478835Z qemu-system-x86_64: sev_ram_block_added: failed to register region (0x7f3df3e00000+0x200000000)
2018-03-05T13:40:12.489183Z qemu-system-x86_64: sev_ram_block_added: failed to register region (0x7f3ffaa00000+0x37c000)
2018-03-05T13:40:12.497580Z qemu-system-x86_64: sev_ram_block_added: failed to register region (0x7f3ffa800000+0x20000)
2018-03-05T13:40:12.504485Z qemu-system-x86_64: sev_launch_update_data: LAUNCH_UPDATE ret=-12 fw_error=0 ''
2018-03-05T13:40:12.504493Z qemu-system-x86_64: failed to encrypt pflash rom

Here's my full QEMU command line (started by libvirt) -- this command line does not restrict pflash access to guest code that runs in SMM, and correspondingly, the OVMF build lacks SMM_REQUIRE:

/opt/qemu-installed/bin/qemu-system-x86_64 \
  -name guest=from-brijesh,debug-threads=on \
  -S \
  -object secret,id=masterKey0,format=raw,file=/var/lib/libvirt/qemu/domain-4-from-brijesh/master-key.aes \
  -machine pc-q35-2.10,accel=kvm,usb=off,smm=on,dump-guest-core=off \
  -cpu host \
  -drive file=/home/virt-images/OVMF_CODE.4m.fd,if=pflash,format=raw,unit=0,readonly=on \
  -drive file=/var/lib/libvirt/qemu/nvram/from-brijesh_VARS.fd,if=pflash,format=raw,unit=1 \
  -m 8192 \
  -realtime mlock=off \
  -smp 1,sockets=1,cores=1,threads=1 \
  -uuid e2373f13-f481-4008-88d0-d61fa9da16fe \
  -no-user-config \
  -nodefaults \
  -chardev socket,id=charmonitor,path=/var/lib/libvirt/qemu/domain-4-from-brijesh/monitor.sock,server,nowait \
  -mon chardev=charmonitor,id=monitor,mode=control \
  -rtc base=utc \
  -no-shutdown \
  -boot strict=on \
  -device pcie-root-port,port=0x10,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,addr=0x2 \
  -device pcie-root-port,port=0x11,chassis=2,id=pci.2,bus=pcie.0,addr=0x2.0x1 \
  -device pcie-root-port,port=0x12,chassis=3,id=pci.3,bus=pcie.0,addr=0x2.0x2 \
  -device pcie-root-port,port=0x13,chassis=4,id=pci.4,bus=pcie.0,addr=0x2.0x3 \
  -device nec-usb-xhci,id=usb,bus=pci.1,addr=0x0 \
  -device virtio-scsi-pci,iommu_platform=on,ats=on,id=scsi0,bus=pci.3,addr=0x0 \
  -drive file=/var/lib/libvirt/images/rhel-7-server.qcow2,format=qcow2,if=none,id=drive-scsi0-0-0-0,cache=writeback,discard=unmap,werror=enospc \
  -device scsi-hd,bus=scsi0.0,channel=0,scsi-id=0,lun=0,drive=drive-scsi0-0-0-0,id=scsi0-0-0-0,bootindex=1 \
  -netdev tap,fd=26,id=hostnet0,vhost=on,vhostfd=28 \
  -device virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00:65:f7:fb,bus=pci.4,addr=0x0,rombar=0 \
  -chardev pty,id=charserial0 \
  -device isa-serial,chardev=charserial0,id=serial0 \
  -device usb-tablet,id=input2,bus=usb.0,port=1 \
  -spice port=5900,addr=127.0.0.1,disable-ticketing,seamless-migration=on \
  -device cirrus-vga,id=video0,bus=pcie.0,addr=0x1 \
  -device virtio-balloon-pci,id=balloon0,bus=pci.2,addr=0x0 \
  -global isa-debugcon.iobase=0x402 \
  -debugcon file:/tmp/from-brijesh.log \
  -fw_cfg name=opt/ovmf/PcdResizeXterm,string=y \
  -s \
  -object sev-guest,id=sev0,policy=0x0,cbitpos=47,reduced-phys-bits=5 \
  -machine memory-encryption=sev0 \
  -msg timestamp=on

Thanks,
Laszlo