Problem creating domU guest on arm64

[Marco Cacre <marco.cacre@xxxxxxxxx>]

Hi all,

I'm facing two kind of problem trying to create a Xen guest domain on rockpro64 (arm64).

I have successfully built uboot, xen (4.14.4) and dom0 linux kernel with xen tool stack, these two last starting from buildroot (with linux kernel version 5.15.33 and xen toolstack version 4.14.4)

These are the process of Xen:

177 root    /usr/sbin/xenwatchdogd 30 15
203 root    /usr/sbin/xenstored --pid-file /var/run/xen/xenstored.pid
208 root    /usr/sbin/xenconsoled --pid-file=/var/run/xen/xenconsoled.pid
214 root    /usr/lib/xen/bin/qemu-system-i386 -xen-domid 0 -xen-attach -name dom0 -nographic -M xenpv -daemonize -monitor /dev/null -serial/dev/nul -parallel/dev/null -pidfile/var/run/xen/qemu-dom0.pid

and the drivers loaded as a module:
# lsmod
Module                  Size  Used by    Tainted: G
xen_netback            65536  0
xen_blkback            49152  0

Xen and dom0 Image boot up successfully, at the end:
================================================
>xl list
Name                                        ID  Mem VCPUs State Time(s)
Domain-0                                    0  1024    2    r-----    4000.3

# uname -a
Linux rockpro64 5.15.33 #3 SMP PREEMPT Fri Apr 15 11:01:37 CEST 2022 aarch64 GNU/Linux
================================================

when I try to create a domU domain I have problem with disk backend, I have made several attempts trying with different domU linux and I always get the following error :

================================================
Parsing config from ./alpine_xen_domu.config

libxl: error: libxl_aoutils.c:539:async_exec_timeout: killing execution of /etc/xen/scripts/block add because of timeout
libxl: error: libxl_create.c:1608:domcreate_launch_dm: Domain 2:unable to add disk devices
libxl: error: libxl_aoutils.c:539:async_exec_timeout: killing execution of /etc/xen/scripts/block remove because of timeout
libxl: error: libxl_domain.c:1182:libxl__destroy_domid: Domain 2:Non-existant domain
libxl: error: libxl_domain.c:1136:domain_destroy_callback: Domain 2:Unable to destroy guest
libxl: error: libxl_domain.c:1063:domain_destroy_cb: Domain 2:Destruction of domain failed
================================================

The last try was with alpine domU linux with the following config:
================================================

# Alpine Linux PV DomU
# Kernel paths for install
kernel = "/home/xen/vmlinuz-virt"
ramdisk = "/home/xen/initramfs-virt"
extra="modules=loop,squashfs console=hvc0"
# Path to HDD and iso file
disk = [ 'format=raw, vdev=xvda, access=w, target=/data/a1.img',
        'format=raw, vdev=xvdc, access=r, devtype=cdrom, target=/home/xen/alpine-virt-3.15.3-armv7.iso'  ]
# Network configuration                                        
vif = ['bridge=br0']
# DomU settings                                                              
memory = 512                                                                  
name = "alpine-a1"                                                            
vcpus = 1                                                                    
maxvcpus = 1
================================================

thanks a lot in advance
Best regards
Marco