How to create more than one DomU using xen with linux BSP 5.4.70?

[eliozepeda]

Hello friends, I created one container "DomU" following the steps in the Linux 5.4.70_2.3.0​ documentation (https://www.nxp.com/webapp/Download?colCode=L5.4.70_2.3.0_LINUX_DOCS), to create the Image with xen I followed the chapters 5.0 - 5.4 and 5.6.11 in Yocto_project_User_Guide and then I followed the steps of chapter 12 Virtualization of Linux_Users_Guide and I was able to create the vm DomU...

Now I want to create more than one virtual machine, I tried changing the name in the file domu-imx8qm-mek.cfg that is the configuration file to create the first virtual machine DomU but I face the next errors:

root@imx8qmmek:~# xl create /etc/xen/domu-imx8qm-mek.cfg
Parsing config from /etc/xen/domu-imx8qm-mek.cfg
libxl: info: libxl_create.c:119:libxl__domain_build_info_setdefault: qemu-xen is unavailable, using qemu-xen-traditional instead: No such file or directory
(XEN) ****************************************************
(XEN) NOT FOUND A entry to power off passthrough resources
(XEN) The dts node name needs to be same as name = "xxx"
(XEN) in vm configuration file
(XEN) ****************************************************
libxl: error: libxl_arm.c:902:copy_partial_fdt: Can't copy the node "/passthrough" from the partial FDT
libxl: error: libxl_arm.c:902:copy_partial_fdt: Can't copy the node "/passthrough" from the partial FDT
libxl: error: libxl_arm.c:902:copy_partial_fdt: Can't copy the node "/passthrough" from the partial FDT
libxl: error: libxl_arm.c:934:copy_partial_fdt: Can't copy the node /bus@56000000 from the partial FDT
libxl: error: libxl_arm.c:934:copy_partial_fdt: Can't copy the node /bus@5a000000 from the partial FDT
[ 448.891629] imx-sc-thermal scu:thermal-sensor: failed to register sensor: 0
[ 448.899329] imx-sc-thermal scu:thermal-sensor: failed to register thermal sensor: -517
[ 448.918090] pwm-backlight lvds_backlight@0: lvds_backlight@0 supply power not found, using dummy regulator
(XEN) printk: 7 messages suppressed.
(XEN) IRQ 33 is already used by domain 1
libxl: error: libxl_create.c:1481:domcreate_launch_dm: Domain 3:failed give domain access to irq 33: Device or resource busy
libxl: error: libxl_domain.c:1177:libxl__destroy_domid: Domain 3:Non-existant domain
libxl: error: libxl_domain.c:1131:domain_destroy_callback: Domain 3:Unable to destroy guest
libxl: error: libxl_domain.c:1058:domain_destroy_cb: Domain 3:Destruction of domain failed

Right now I have three partitions in mi SD card, according to the Yocto_Project_User_Guide "To boot two Yocto Operating Systems, create three partitions on the SD card (no less than 16 GB). The first partition is FAT, used to hold Xen, image, and imx8qm-mek-dom0.dtb. The second and third partitions are used to hold Yocto rootfs." 

Do I need one partition with rootfs for every Virtual Machine that I want to create?

Can I use the same imx8qm-mek-domu.dtb file to create several virtual machines? 

What is the maximum number of vms  that I can create using an SD card?

I hope you can help me with this questions.

Thanks!

[Sanket_Parekh]

Hi @eliozepeda 

I hope you are doing well.

Do I need one partition with rootfs for every Virtual Machine that I want to create?
[Ans]: You need a separate partition with rootfs for each Domu created. 

Can I use the same imx8qm-mek-domu.dtb file to create several virtual machines?
[Ans]: One has to create separate dts and configuration file for each DomU created.

Thanks & Regards,

Sanket Parekh

[eliozepeda]

@Sanket_Parekh  thanks for your answer do you know where I can found documentation to create a new dts and configuration file? 

Thanks.

[Sanket_Parekh]

Hi @eliozepeda 

NXP doesn't provide documentation for creating more than one DomU using Xen.

However, One can refer to the below-mentioned documents.

1. https://xenbits.xen.org/docs/unstable/misc/arm/device-tree/booting.txt

2. https://xenbits.xen.org/docs/unstable/man/xl.cfg.5.html // for configuration file.

Thanks & Regards,

Sanket Parekh