Hi!
I stumbled upon the exact same issue with bullseye. Turns out, upgrading
the kernel to Linux 5.18 fixes the issue. I have not pinpointed the
exact bug/patch that resolves this.
More precisely, I upgraded the kernel image to
5.18.0-0.bpo.1-cloud-amd64 using the
debian-11-nocloud-amd64-20220613-1045.qcow2 image as a base. Tested on
Qemu 7.0.
Best regards,
Olivier
On Sun, 11 Apr 2021 20:12:20 +0200 =?utf-8?B?SsOhbiBNw6F0w6k=?=
<jan.m...@inf-it.com> wrote:
> Package: qemu-system-x86
> Version: 1:5.2+dfsg-9
>
> When I try to boot an AMD SEV enabled guest OS it crashes immediately
after the "Loading initial ramdisk ..." message (the result is infinite
reboot loop). Here is my libvirt XML which works fine without the
"<launchSecurity...>...<launchSecurity/>" XML element (which enables the
AMD SEV):
>
> <domain type='kvm'>
> <name>test</name>
> <uuid>4dea22b3-1d52-d8f3-2516-782e98ab3fa0</uuid>
> <genid>ab826c0a-a349-4470-bbb9-d2b6ee23e8c3</genid>
> <title>Test Server</title>
> <memory dumpCore='off' unit='KiB'>8388608</memory>
> <currentMemory unit='KiB'>8388608</currentMemory>
> <memtune>
> <hard_limit unit='KiB'>9437184</hard_limit>
> </memtune>
> <memoryBacking>
> <hugepages>
> <page size='2048' unit='KiB'/>
> </hugepages>
> <locked/>
> <source type='memfd'/>
> <access mode='shared'/>
> <allocation mode='immediate'/>
> <discard/>
> </memoryBacking>
> <vcpu placement='static'>4</vcpu>
> <iothreads>1</iothreads>
> <os firmware='efi'>
> <type arch='x86_64' machine='pc-q35-5.2'>hvm</type>
> <loader secure='yes'/>
> <nvram>/var/lib/libvirt/qemu/nvram/test_VARS.fd</nvram>
> <bootmenu enable='yes' timeout='5000'/>
> <bios useserial='yes'/>
> <smbios mode='emulate'/>
> </os>
> <features>
> <acpi/>
> <apic/>
> <pae/>
> <hap state='on'/>
> <privnet/>
> <kvm>
> <hidden state='off'/>
> <hint-dedicated state='on'/>
> <poll-control state='on'/>
> </kvm>
> <pvspinlock state='on'/>
> <ioapic driver='kvm'/>
> </features>
> <cpu mode='host-passthrough' check='none' migratable='off'>
> <topology sockets='1' dies='1' cores='2' threads='2'/>
> <cache mode='passthrough'/>
> <feature policy='require' name='topoext'/>
> </cpu>
> <clock offset='utc'>
> <timer name='kvmclock' present='yes'/>
> </clock>
> <on_poweroff>destroy</on_poweroff>
> <on_reboot>restart</on_reboot>
> <on_crash>coredump-restart</on_crash>
