qubes-linux-utils/udev/udev-qubes-dmroot.rules

# Create /dev/mapper/dmroot symlink on TemplateVM/StandaloneVM to make
# grub-mkconfig happy.
# On TemplateBasedVM, it is really a device mapper device.

SUBSYSTEM=="block", ENV{ID_PART_ENTRY_NAME}=="Root\x20filesystem", ATTR{ro}=="0", SYMLINK+="mapper/dmroot"
udev: create /dev/mapper/dmroot -> xvda3 symlink when its mounted directly When root device is available read-write (TemplateVM/StandaloneVM), its mounted directly, instead of using device-mapper layer. But /dev/mapper/dmroot still needs to exists (it is pointed from /etc/fstab), otherwise various tools, including grub-mkconfig get confused. Create a symlink using udev rule. It is already done in initramfs, and in case of Fedora that udev rule/symlink survive switching to non-initramfs udev, but not on Debian. So, add appropriate udev rules file. Fixes QubesOS/qubes-issues#3178 2018-06-13 13:48:00 +00:00			`# Create /dev/mapper/dmroot symlink on TemplateVM/StandaloneVM to make`
			`# grub-mkconfig happy.`
			`# On TemplateBasedVM, it is really a device mapper device.`

			`SUBSYSTEM=="block", ENV{ID_PART_ENTRY_NAME}=="Root\x20filesystem", ATTR{ro}=="0", SYMLINK+="mapper/dmroot"`