Re: [Qemu-devel] [PATCH v3 00/10] Implement network booting directly into the s390-ccw BIOS

[Christian Borntraeger]

On 07/10/2017 05:32 PM, Thomas Huth wrote:
> It's already possible to do a network boot of an s390x guest with an
> external netboot image based on a Linux installation, but it would
> be much more convenient if the s390-ccw firmware supported network
> booting right out of the box, without the need to assemble such an
> external image first.
> 
> This patch series now introduces a s390-netboot.img that can be used
> for network booting via DHCP and TFTP by re-using the networking stack
> from the SLOF firmware (see https://github.com/aik/SLOF/ for details),
> and adds a driver for virtio-net-ccw devices.
> 
> The code can only be built if the roms/SLOF submodule has been checked
> out (there is a sanity check for this in the Makefile). Once it has
> been built, you can download a combined kernel + initrd image via TFTP
> by starting QEMU for example with:
> 
>  qemu-system-s390x ... -device virtio-net,netdev=n1,bootindex=1 \
>        -netdev user,id=n1,tftp=/path/to/tftp,bootfile=kernel.img
> 
> Note that this version does not support downloading via config
> files (i.e. pxelinux config files or .INS config files) yet. This
> will be added later.
> 
> v3:
>  - Adressed the review feedback from v2
>  - The last remaining SLOF patch has now been merged (big thanks to
>    Alexey!), so not sending this as RFC anymore - it is ready now for
>    integration, I think.
> 
> v2:
>  - Put the network boot loader into a separate s390-netboot.img
>    binary instead of linking it directly into the s390-ccw firmware.
>  - Use the SLOF sources from the roms/SLOF/ submodule instead of
>    copying them into the pc-bios/s390-ccw folder
>  - Removed the .INS config file loading code for now - only support
>    combined kernel + initrd images in this initial implementation.
> 
> Thomas Huth (10):
>   pc-bios/s390-ccw: Move libc functions to separate header
>   pc-bios/s390-ccw: Move ebc2asc to sclp.c
>   pc-bios/s390-ccw: Move virtio-block related functions into a separate
>     file
>   pc-bios/s390-ccw: Add a write() function for stdio
>   pc-bios/s390-ccw: Move byteswap functions to a separate header
>   pc-bios/s390-ccw: Add code for virtio feature negotiation
>   roms/SLOF: Update submodule to latest status
>   pc-bios/s390-ccw: Add core files for the network bootloading program
>   pc-bios/s390-ccw: Add virtio-net driver code
>   pc-bios/s390-ccw: Link libnet into the netboot image and do the TFTP
>     load
> 
>  pc-bios/s390-ccw/Makefile        |  13 +-
>  pc-bios/s390-ccw/bootmap.c       |   2 +
>  pc-bios/s390-ccw/bootmap.h       |  26 ---
>  pc-bios/s390-ccw/bswap.h         |  25 +++
>  pc-bios/s390-ccw/libc.h          |  45 +++++
>  pc-bios/s390-ccw/main.c          |  14 +-
>  pc-bios/s390-ccw/netboot.mak     |  51 ++++++
>  pc-bios/s390-ccw/netmain.c       | 365 
> +++++++++++++++++++++++++++++++++++++++
>  pc-bios/s390-ccw/s390-ccw.h      |  33 +---
>  pc-bios/s390-ccw/sclp.c          |  37 ++--
>  pc-bios/s390-ccw/virtio-blkdev.c | 297 +++++++++++++++++++++++++++++++
>  pc-bios/s390-ccw/virtio-net.c    | 133 ++++++++++++++
>  pc-bios/s390-ccw/virtio-scsi.c   |   1 +
>  pc-bios/s390-ccw/virtio.c        | 306 ++++----------------------------
>  pc-bios/s390-ccw/virtio.h        |  18 +-
>  roms/SLOF                        |   2 +-
>  16 files changed, 1007 insertions(+), 361 deletions(-)
>  create mode 100644 pc-bios/s390-ccw/bswap.h
>  create mode 100644 pc-bios/s390-ccw/libc.h
>  create mode 100644 pc-bios/s390-ccw/netboot.mak
>  create mode 100644 pc-bios/s390-ccw/netmain.c
>  create mode 100644 pc-bios/s390-ccw/virtio-blkdev.c
>  create mode 100644 pc-bios/s390-ccw/virtio-net.c
> 

Generic Ack for all patches from me. I will give it some more review on the 
list,
but since this is standalone I will pick up this patch series unless review
has some findings.