Re: [edk2-devel] [PATCH 00/17] [RFC] OvmfPkg: Add support for microvm machine type

["Yao, Jiewen" <jiewen.yao@intel.com>]

That is good info.

I recommend to add microvm feature to the https://github.com/tianocore/edk2/blob/master/Maintainers.txt

OvmfPkg: microvm-related modules
F: OvmfPkg/microvm/
F: OvmfPkg/Include/IndustryStandard/Microvm.h    

I also recommend you to be reviewer for the feature.
Feel free to add other people as reviewer too, if you think he/she can help review the patch set.


Thank you
Yao Jiewen

> -----Original Message-----
> From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Gerd
> Hoffmann
> Sent: Wednesday, September 1, 2021 3:25 PM
> To: Yao, Jiewen <jiewen.yao@intel.com>
> Cc: devel@edk2.groups.io; Marc-André Lureau
> <marcandre.lureau@redhat.com>; Anthony Perard
> <anthony.perard@citrix.com>; Ard Biesheuvel <ardb+tianocore@kernel.org>;
> Justen, Jordan L <jordan.l.justen@intel.com>; Julien Grall <julien@xen.org>;
> Stefan Berger <stefanb@linux.ibm.com>
> Subject: Re: [edk2-devel] [PATCH 00/17] [RFC] OvmfPkg: Add support for
> microvm machine type
> 
> On Tue, Aug 31, 2021 at 02:32:45PM +0000, Yao, Jiewen wrote:
> > Thank you. That confirms my guess.
> >
> > If you can add all those info in readme, that would be great, especially the URL
> https://qemu.readthedocs.io/en/latest/system/i386/microvm.html, as well as
> the scope.
> 
> Current README below (also covering the not-yet submitted
> virtio-mmio and pcie patches).
> 
> take care,
>   Gerd
> 
> -------------------- cut here -----------------------
> 
> This is an *experimental* port of OVMF for the qemu microvm
> machine type.
> 
> microvm background info
> -----------------------
> 
> microvm is designed for modern, virtio-based workloads.  Most legacy
> lpc/isa devices like pit and pic can be turned off.  virtio-mmio
> (i.e. '-device virtio-{blk,net,scsi,...}-device') is used for
> storage/network/etc.
> 
> Optional pcie support is available and any pcie device supported by
> qemu can be plugged in (including virtio-pci if you prefer that over
> virtio-mmio).
> 
> https://qemu.readthedocs.io/en/latest/system/i386/microvm.html
> https://www.kraxel.org/blog/2020/10/qemu-microvm-acpi/
> 
> design issues
> -------------
> 
> Not fully clear yet how to do hardware detection best.  Right now
> using device tree to find virtio-mmio devices and pcie host bridge,
> can reuse existing ArmVirtPkg code that way.  Needs patched qemu.
> 
> features
> --------
>  [working] serial console
>  [working] direct kernel boot
>  [in progress] virtio-mmio support
>  [in progress] pcie support
> 
> known limitations
> -----------------
>  * rtc=on is required for now.
>  * can't use separate code/vars (actually an microvm limitation,
>    there is no pflash support).
>  * transitional virtio-pci devices do not work.  microvm doesn't
>    support ioports on pcie, and ovmf doesn't initialize pcie devices
>    with ioports if there is no address space for them (even though
>    pcie devices are required to be functional without ioports).
> 
> known bugs
> ----------
>  * timer has wrong frequency (running fast on my hardware).
> 
> usage
> -----
> qemu-system-x86_64 \
>     -nographic \
>     -machine microvm,acpi=on,pit=off,pic=off,rtc=on \
>     -bios /path/to/MICROVM.fd \
>     [ ... more args here ... ]
> 
> 
> 
> 
>