Thanks. This put me on the right track and I was able to solve the problem. I will summarise the steps I took. (The PCI address in my case is 26:00.0 - take that into account when reading further)
On the KVM host, execute the following: dmesg | grep -i 'vfio.*26[:]00' This produced the following: vfio-pci 0000:26:00.0: BAR 0: can't reserve [mem 0xe0000000-0xefffffff 64bit pref] These entries indicates that the VM cannot access all IO memory of the PCI device. To find out which module grabbed the IO memory, do the following in the KVM host: grep -B 5 -A 5 "26[:]00" /proc/iomem This had the following entry: e0000000-e01effff : efifb This address block is inside the block that could not be reserved for the VM and efifb (EFI Frame Buffer) grabbed this memory. In my case, the PCI device was also the primary device configured for the PC in EFI. It could also be be vesafb (VESA Frame Buffer). The vesafb or efifb uses this address block for virtual consoles. (See /sys/class/vtconsole/vtcon0 and vtcon1). I tried the following options from the given references: echo 0 > /sys/class/vtconsole/vtcon0/bind echo 0 > /sys/class/vtconsole/vtcon1/bind reboot - this did not solve the problem I also tried a solution which requires that edit /etc/default/grub: GRUB_CMDLINE_LINUX_DEFAULT="<other options> video=vesa:off,efifb:off" update-initramfs -u update-grub reboot - this did not solve the problem either Then I some more options: GRUB_CMDLINE_LINUX_DEFAULT="<other options> vga=normal nofb nomodeset video=efifb:off" update-initramfs -u update-grub reboot - this solved the problem and after reboot efifb did not lock that address range any more. Reference: https://support.digium.com/community/s/article/How-to- disable-the-Linux-frame-buffer-if-it-s-causing-problems -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1776269 Title: Installer causes VM to be paused To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/qemu/+bug/1776269/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs