Re: Cannot turn iommu on inside guest

On Tue, Feb 11, 2020 at 09:09:36AM -0500, Mauricio Tavares wrote: > So I want to turn iommu support on in a guest ( <type arch='x86_64' > machine='pc-q35-4.1'>hvm</type>). Per [1] I tried to add to devices > either > > <devices> > <iommu model='intel'> > <driver intremap='on'/> > </iommu> > </devices> > > or just a simpler > > <devices> > <iommu model='intel /'> > </devices> > > However, when I try to boot it, it crashes with the following error > message (stolen from /var/log/libvirt/qemu/testkvm.log): > > 2020-02-11T05:13:27.278707Z qemu-system-x86_64: We need to set > caching-mode=on for intel-iommu to enable device assignment with IOMMU > protection. > 2020-02-11 05:13:27.577+0000: shutting down, reason=crashed > > that sounds like it wants me to do something like > > qemu-system-x86_64 [...] -device intel-iommu,intremap=on,caching-mode=on[2] > > using virsh. But > > <devices> > <iommu model='intel'> > <driver intremap='on' caching-mode='on '/> You need caching_mode="on" - notice underscore, not hypehn

> </iommu> > </devices> > > is not only not mentioned in [1] but also fails The correctly spelt caching_mode is mentioned there. > > [root@testbox tests]# virsh edit testkvm > error: XML document failed to validate against schema: Unable to > validate doc against /usr/share/libvirt/schemas/domain.rng > Extra element devices in interleave > Element domain failed to validate content > > Failed. Try again? [y,n,i,f,?]: > > Can anyone show me what I am missing here? > > [1] https://libvirt.org/formatdomain.html#elementsIommu > [2] https://wiki.qemu.org/Features/VT-d#Command_Line_Example_2 > > Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|