Re: [Qemu-devel] Assigning an eth port to a guest VM

[Yehuda Yitschak <yehuday@marvell.com>]

Cc: Eric Auger

> -----Original Message-----
> From: Yehuda Yitschak
> Sent: Monday, June 15, 2015 9:35
> To: qemu-devel@nongnu.org
> Cc: Yuval Caduri; Shadi Ammouri
> Subject: Assigning an eth port to a guest VM
> 
> Hello
> 
> I would to ask your advice on how to assign a semi-virtualized Ethernet port
> to a guest VM
> 
> The eth port's HW partially supports virtualization since the data path MMIO
> registers (which controls rx/tx operation) are duplicated per VM.
> So for the run-time operation the guest can directly access the MMIO
> registers, using VFIO-PLATFORM, and enjoy the performance benefit.
> 
> However for the initial setup and occasional configuration the guest need to
> access control path registers which are shared for all guests.
> AFAIK this is usually done with HW emulation using trap & emulate with
> QEMU.
> So, to the best of my knowledge I need a mix of VFIO and HW emulation to
> get the port to work with device assignment , right ?
> 
> Are there any standard methods for achieving this ?
> Is there an example for such an existing HW in QEMU ?
> 
> Thanks
> 
> Yehuda Yitschak