[vfio-users] two gpus

[Roger Lawhorn]

ok,

Well, the bug report I read said that all addr values must be 00.0 for 
it all to work.
That fixed it for me.


On 6/23/20 11:48 PM, Alex Williamson wrote:
> On Tue, 23 Jun 2020 23:33:22 -0400
> Roger Lawhorn <rll at twc.com> wrote:
>
>> I have the answer.
>>
>> I had to change my lines from:
>> -device
>> vfio-pci,host=0c:00.0,bus=root_port1,addr=00.0,multifunction=on,x-vga=on \
>> -device vfio-pci,host=0c:00.1,bus=root_port2,addr=00.1,multifunction=on \
>> -device vfio-pci,host=0d:00.0,bus=root_port3,addr=01.0,multifunction=on \
>>
>> to:
>> -device
>> vfio-pci,host=0c:00.0,bus=root_port1,addr=00.0,multifunction=on,x-vga=on \
>> -device vfio-pci,host=0c:00.1,bus=root_port2,addr=00.0,multifunction=on \
>> -device vfio-pci,host=0d:00.0,bus=root_port3,addr=00.0,multifunction=on \
>>
>>
>> Apparently, this is a known bug.
>> All cards must be on the same addr.
>>
>> I have both gpus and 8gb of vmem instead of just 4gb.
>>
>> Nice to know you CAN have more than one video card with gpu passthrough.
> That's not a bug, that's how PCI function number and PCIe slot numbering
> works.  You can't have a function number >0 without a function 0 with
> multifunction=on in the same slot and you can't have a slot number >0
> under a PCIe downstream port.
>