update kernel 5.15,boot stopped on "Timed out waiting for device dev-mapper-rl\x2dswap.device"

[yc lee]

A new RockyLinux8.5(CentOS8.5) VM is installed on XenServer8.2 host. There is no problem with the 4.18 kernel. After upgrading to the latest 5.15 kernel, the boot fails "dracut Warning: /dev/mapper/rl-root does not exsit"

journalctl

show error "Timed out waiting for device dev-mapper-rl\x2dswap.device"

After checking, I feel that the disk cannot be found when starting up Boot is a separate partition, the root partition and swap partition are both on the lvm partition I add "xen_emul_unplug=never" to /boot/grub2/grub.cfg ,the VM can boot success.

After installing xe-guest-utilities, vio and vif drivers do not take effect.

Are there any special options in the kernel after 5.13 that affect the virtual machine of the xen platform?

[yc lee]

I have solved this problems by self.

I recompiled the 5.15 kernel, and found that in the default compilation configuration, "Xen Virtual Block Device Support" and "Xen Block Device Backend Driver" are compiled in module (M) mode, I changed it to built-in mode (*) to compile, all the problems are solved. The VM can be started without adding the "xen_emul_unplug=never" parameter, and the VM-guest-tools status is also normal.

[yc lee]

Another solution is to regenerate the boot image.
 

dracut -v -f -H -k /usr/lib/modules/5.15.8-1.el8.elrepo.x86_64/ --add-drivers "xen-blkfront xen-netfront dm-mod" initramfs-5.15.8-1.el8.elrepo.x86_64.img 5.15.8-1.el8.elrepo.x86_64