Since xen cannot build /usr/local/lib/xen/bin/qumu-dm can we get a work around?

from drakvuf.

Use the pre-packaged deb files from the drakvuf-builds repo.

from drakvuf.

I removed the old .../git/drakvuf/xen/dist/*.deb package "xen-upstream" (from dpkg -l) then downloaded the build:
ubuntu_focal_xen-hypervisor-4.17.0-generic-amd64.deb , for ubuntu 20.04,
and installed the new build -- but still no qemu-dm which still is required from 'xl create -c <path/vm.cfg>'

Just to check I also downloaded the ubuntu_focal_drakvuf-bundle-1.1-git20230221092926+8260f2f-1-generic.deb
and installed it too, but still no qemu-dm and still cannot create a VM -- since I am checking out injection, I would need to re-build drakvuf anyway, but just decided to check if qemu-dm would be installed from that package (which I believe is most assuredly wrong).

Perhaps I did something wrong?

from drakvuf.

I'm not sure what error you are seeing but the pre-built packages are working fine. There is no such binary qemu-dm used by Xen. Xen uses qemu-system-i386 for VMs.

from drakvuf.

I am probably using something old-ish in the cfg file. This file used to work on 4.16, and this cfg has been around since 2018.

I am really wondering if the problem is my cfg line:
device_model_version="qemu-xen-traditional"

libxl_dm.c:2899 has to do with the libxl__domain_device_model call.
I will remove the line and see if that fixes it?

Here is the output of

xl create -c /etc/xen/vm1.cfg

Parsing config from /etc/xen/vm1.cfg
libxl: error: libxl_dm.c:2899:libxl__spawn_local_dm: Domain 4:device model /usr/lib/xen/bin/qemu-dm is not executable: No such file or directory
libxl: error: libxl_dm.c:3148:device_model_spawn_outcome: Domain 4:(null): spawn failed (rc=-3)
libxl: error: libxl_dm.c:3368:device_model_postconfig_done: Domain 4:Post DM startup configs failed, rc=-3
libxl: error: libxl_create.c:1894:domcreate_devmodel_started: Domain 4:device model did not start: -3
libxl: error: libxl_domain.c:1183:libxl__destroy_domid: Domain 4:Non-existant domain
libxl: error: libxl_domain.c:1137:domain_destroy_callback: Domain 4:Unable to destroy guest
libxl: error: libxl_domain.c:1064:domain_destroy_cb: Domain 4:Destruction of domain failed

$ cat vm1.cfg
arch = 'x86_64'
name = "vm1"
maxmem = 1024
memory = 1024
vcpus = 1
maxcpus = 1
builder = "hvm"
hap = 1
acpi = 1
on_poweroff = "destroy"
on_reboot = "destroy"
on_crash = "destroy"
vnc=1
vnclisten="0.0.0.0"
vga = "stdvga"
usb = 1
usbdevice = "tablet"
viridian = 1
altp2m = 2
shadow_memory = 16
on_crash="preserve"
device_model_version="qemu-xen-traditional"
vif = [ 'type=ioemu,model=e1000,bridge=xenbr0,mac=E4:42:A6:BA:7C:01' ]
boot = "dc"
disk = [ 'phy:/dev/vg/vm1,hda,w' , 'file:/root/cdrom/ubuntu-focal-20.04-server.iso,hdc:cdrom,r' ]

there is nothing new in /var/log/xen when run.

from drakvuf.

That works! I guess I no longer need to have device_model_version="qemu-xen-traditional" in the cfg, I just commented it out, now xl probably chooses qemu-xen.

What a horrible error message.

Thanks Tamas!!! I thought the error was a build problem.

from drakvuf.

qemu-traditional is no longer built by default (or used) by Xen since the 4.16 release. There are very few edge-cases where it's needed. Not sure where you go that config from, we never used it with DRAKVUF. In case anyone needs it in the future, you need to build the Xen tools by configuring with --enable-qemu-traditional to make it available.

from drakvuf.