Problem with xen config

[Jim Fehlig]

On 7/27/20 9:17 AM, Christoph wrote:
> Hi all,
> 
> I 've such a config on xen (4.14):
> 
> name = "marax.chao5.int"
> uuid = "e0de3cb7-3937-417d-8d63-b0993b377b6a"
> maxmem = 16384
> memory = 16384
> kernel = '/usr/lib64/xen/boot/hvmloader'
> vcpus = 16
> rtc_timeoffset = 0
> localtime = 1
> on_poweroff = "destroy"
> on_reboot = "restart"
> on_crash = "restart"
> vif = [
> "mac=00:16:3e:05:01:10,bridge=xenbr5,script=vif-bridge,model=e1000" ]
> parallel = "none"
> serial = "none"
> type = "hvm"
> loader = "/usr/lib64/xen/boot/hvmloader"
> disk = [ "phy:/dev/mapper/marax_c,hda,rw",
> "phy:/dev/vg_lilith/lv_marax_d,hdb,rw" ]
> max_grant_frames = "128"
> pci = [ "01:00.0", "01:00.1", "01:00.2", "01:00.3", "00:1f.3", "05:00.0"
> ]
> pci_permissive  = 1
> keymap = "de"
> vnclisten="0.0.0.0"
> pci_power_mgmt=1
> xen_platform_pci=1
> pci_msitranslate=1
> viridian=1
> hpet=1
> acpi=1
> apic=1
> pae=1
> 
> I want to convert it to a xml format for use it with libvirt/virsh but I
> get an error:
> "error: An error occurred, but the cause is unknown"
> 
> If I comment out the line with pci = [ "01:00.0", "01:00.1", "01:00.2",
> "01:00.3", "00:1f.3", "05:00.0" ]
> then it works but I dont see the settings like
> 
> xen_platform_pci=1

This setting is not supported in the libvirt libxl driver, but AFAICT libxl sets 
the default to 'true' for HVM guests.

> pci_msitranslate=1

This is also not supported in libvirt and unfortunately defaults to 'false'.

> pci_permissive = 1

Patches have been submitted for this setting but so far there has not been 
agreement on the schema change

https://www.redhat.com/archives/libvir-list/2020-April/msg01230.html

> max_grant_frames = "128

This, along with max_event_channels, is supported as an attribute on the xenbus 
controller, e.g.

<controller type='xenbus' maxGrantFrames='128' maxEventChannels='2047'/>

> and the pci passthrough devices are not there...

Is setting maxGrantFrames (and possibly maxEventChannels) on the xenbus 
controller enough to see the devices in the guest?

Regards,
Jim