[vfio-users] problem with passthrough and unsafe interrupts

[Janusz]

W dniu 13.09.2015 o 00:28, Blank Field pisze:
> Looking at IOMMU groups, his lspci and his problems, there's no way
> anyone would want to take intel for VFIO usage.
> Good lord, that's worse than my system...
>> No BSOD, only silent reboot or reset on uefi bios display, also reset
>> issue for gpu (that was already fixed I think in some kernel/qemu
>> version for hawaii, monitor still gets old display sometimes after
>> turining off or reset VM), in dmesg I found only those:
>>
>> [10145.621272] vgaarb: device changed decodes:
>> PCI:0000:01:00.0,olddecodes=io+mem,decodes=io+mem:owns=io+mem
>> [10145.641778] vgaarb: device changed decodes:
>> PCI:0000:01:00.0,olddecodes=io+mem,decodes=io+mem:owns=io+mem
>> [10145.760058] [drm:check_wm_state] *ERROR* mismatch in DDB state
>> pipe A plane 1 (expected (0,0), found (0,289))
>> [10145.760061] [drm:check_wm_state] *ERROR* mismatch in DDB state
>> pipe A cursor (expected (0,0), found (289,297))
>> [10145.760062] [drm:check_wm_state] *ERROR* mismatch in DDB state
>> pipe B plane 1 (expected (0,0), found (297,586))
>> [10145.760063] [drm:check_wm_state] *ERROR* mismatch in DDB state
>> pipe B cursor (expected (0,0), found (586,594))
>> [10148.490876] vfio_ecap_init: 0000:01:00.0 hiding ecap 0x19 at 0x270
>> [10148.490881] vfio_ecap_init: 0000:01:00.0 hiding ecap 0x1b at 0x2d0
>> [10154.080574] usb 1-12: reset low-speed USB device number 5 using
>> xhci_hcd
>> [10154.372122] usb 1-12: ep 0x81 - rounding interval to 64
>> microframes, ep desc says 80 microframes
>> [10194.443399] kvm: zapping shadow pages for mmio generation wraparound
>> [10194.453708] kvm: zapping shadow pages for mmio generation wraparound
>> [10165.930150] usb 1-12: ep 0x81 - rounding interval to 64
>> microframes, ep desc says 80 microframes
>> [10168.912066] usb 1-12: reset low-speed USB device number 5 using
>> xhci_hcd
>> [10169.203902] usb 1-12: ep 0x81 - rounding interval to 64
>> microframes, ep desc says 80 microframes
>>
>>
>> I can be missing something as I get lot of warnings from i915 driver
>> (known bug for i915 and skylake), but I did grep for kvm and vfio and
>> didn't find anything else
>>
>> I am running now dev version of qemu because I wanted to test if
>> newer version will give better result (it didn't), and didn't
>> compiled back the stable version yet
> And yes, I have AMD Catalyst drivers installed in the guest, but as
> this also happening before it starts to boot windows and when starting
> windows installation, I don't think this is the reason
I think I found some solution. I changed number of threads on cpu from 2
to 1, and windows installation is starting every time now. problem still
is with installed windows - its rebooting every time it wants to start
win10, is windows sensitive for such changes?
When I changed number of threads to 2 and number of cores to 3, problem
still occurs

Also, I upgraded to kernel 4.3-r1

I find that someone reported issue to OVMF that it has problems with
kernel >= 4.2 https://github.com/tianocore/edk2/issues/21, unfortunately
I am not able to test it on 4.1 or 4.0 as on 4.1 I get some weird
operations on null pointer in kernel at boot - segfault, and in 4.0 I
don't even get signal to monitor - probably hardware is too new for
those versions (I know about i915 preliminary support but its not working)

anyway, I am gonna test futher later,  and see if with threads=1,cores=4
will problem still occur after reinstalling win10