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Re: [Xen-users] XEN 4.6 / 4.9 - PCI-Passthrough USB 3.0 win7 / Win10 not working

Am 04.01.2018 um 00:04 schrieb Håkon Alstadheim:
> Den 03. jan. 2018 02:06, skrev Chuck Ritola:
>> On Tue, Jan 2, 2018 at 6:43 AM, Xen Mann <xensemann@xxxxxx> wrote:
> [...]
>>>> For 16.04 and winXP this is working great! The PCIe Card appears in
>>>> Windows device manager, the attached USB-Device shows up in the device
>>>> manager and works like a charm.
>>>> However, this is not possible for my system with win7 and Win10 and the
>>>> very same setup.
> [...]
>>> -> Why is passthrough of USB-PCI-Cards working for XP and Ubuntu 16.04,
>>> even if those USB-Cards do not support FLReset.
>> ... The lack of function-level-reset support does not guarantee
>> failure of passthrough, though it often can introduce undefined
>> behavior when multiple domUs use the device consecutively. These clear
>> after the host is reset. From what I've seen, most devices do not
>> support FLReset but many will pass-through and be usable.
>> It would be good practice to ensure dom0 binds pciback to the
>> passed-through devices on boot so it does not initialize the devices
>> prematurely. Else, they may be in an intolerable state when the domU
>> OS tries to initialize them.
Is it possible to detect this intolerable state, is there a test that I
can run to get closer to this source of the problem?
> Bios & Firmware will (at least partly) initialize USB-cards to allow
> usb-keyboards to work during boot, so hiding the card from dom0 might
> not help that much.
On My Motherboard (Intel C236 Chipset) I can't use USB-devices attached
to the PCI-Card from Etrontech. So for example with it I can't select
the GRUB entry to boot from. Don't know if it does mean anything.
I probably could run a quick test with all my USB-PCIe Cards if they are
recognised if this helps.
Or can it be that bios only uses chipset USB?
> I'm not a programmer so what follows is to be taken with a grain of salt.
> I believe there is a handoff protocol between bios and dom0 that means
> dom0 will manage. This MIGHT mean that domUs will not be so fortunate.
> All this might be affected by various bios settings (something like
> legacy int<whatever> among other things).
dom0 or domU bios settings?
> So tinkering might let you
> muddle through, and then an update or the phase of the moon will mess
> you up again. 
Hey! I got my self a wall clock displaying the phase, useless. But now I
can use this for debugging, even by day! =)
> I have similar problems on my system, and I have been wondering if going
> full UEFI on both the hardware and the domUs might help.
> I have not been able to try out that theory, since I am having trouble
> booting using <code>bios = "ovmf"</code> . I have been able to boot
> domUs using ovmf on occasion, but even then dumU boot hangs for several
> minutes, probably looking for floppies or something. Long story, qemu
> fixes are in the works I belive.
Is it possible to get contact to this team? Offering help in testing a
release on different Hardware or so?

### So the problem of successful passing USB-PCIe to a VM with Xen ###

## Collected knowledge and ideas: ##

-this maybe might not be a direct question about WinXP vs. Win10
-dom0 BIOS config & uefi vs. legacy (Touching USB-PCI device)
   (Hakon Alstadheim) 18-01-04
-most devices do not support FLReset but many will pass-through and be
   (Chuck Ritola) 18-01-04
-Intolerable state of PCI. Avoid: Bind pciback on boot time, to give
domU untouched PCI device
   (Chuck Ritola) 18-01-04

## Open questions ##

Can the DomU-PCI Driver from the PCI-Hardware vendor be involved with
this problem?

Should I give it a try to compile a kernel my self which has pciback
included and not loaded as a model?

What happens when I'm passing a PCI-Device to several machines?
Say the pci-device is not initialized by dum0 drivers.
first domU -> init
   ...doing some stuff
first domU -> deinit ?
second domU -> init ?
   ...doing some stuff ?
seond domU ->deinit ?

-> Why only internal (chipset) USB-Host Controller is working for Win7?
-> Is there a difference between in winXP&16.04 vs. win7&win10?

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