On Mon, Nov 8, 2021 at 5:37 PM Gilboa Davara <gilboad@gmail.com> wrote:
Hello all,

I'm setting up a fairly (?) complex oVirt over Gluster setup built around 3 Xeon servers-turned-into-workstations, each doubling as oVirt node + one primary Fedora VM w/ a dedicated passthrough GPU (+audio and a couple of USB root devices).
One of the servers seems to have some weird issue w/ the passthrough nVidia GPU that seems to require me to edit the VM iommu (1) and passthrough device (2) command line.
I tried using the qemu-cmdline addon to add the missing parameters, but it seems that qemu treats the added parameters as an additional device / iommu instead of editing the existing parameters.

So:
1. How can I view the VM qemu command line?
2. Can I somehow manually edit the qemu command line, either directly or by somehow adding parameters in the HE XML file?

- Gilboa.
[1] iommu:  VM XXX is down with error. Exit message: internal error: qemu unexpectedly closed the monitor: 2021-11-05T14:59:44.499366Z qemu-kvm: We need to set caching-mode=on for intel-iommu to enable device assignment with IOMMU protection.
[2] GPU: May need to add x-vga=off,

BTW, FWIW, by isolated I mean device attached during boot to vfio_pci, and passed to the VM with all of its iommu group members (e.g. nVidia GPU + nVidia HDMI audio).

- Gilboa