Re: [Qemu-devel] [PATCH v4 00/11] Implement network booting in the s390-ccw BIOS

[Viktor Mihajlovski <mihajlov@linux.vnet.ibm.com>]

On 12.07.2017 12:53, Thomas Huth wrote:
> On 12.07.2017 10:33, Christian Borntraeger wrote:
>> On 07/11/2017 03:56 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.
>>>
>>> v4:
>>>  - Cosmetic clean-ups according to the review feedback from v3
>>>  - Fixed bug in the find_dev() function (spotted by Cornelia in v3)
>>>  - Added an additional patch to remove some unused structs from
>>>    virtio.h
>>>
>>> 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 (11):
>>>   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: Remove unused structs from virtio.h
>>>   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         |  30 ++++
>>>  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       | 362 +++++++++++++++++++++++++++++++++++++++
>>>  pc-bios/s390-ccw/s390-ccw.h      |  33 +---
>>>  pc-bios/s390-ccw/sclp.c          |  37 ++--
>>>  pc-bios/s390-ccw/virtio-blkdev.c | 296 ++++++++++++++++++++++++++++++++
>>>  pc-bios/s390-ccw/virtio-net.c    | 135 +++++++++++++++
>>>  pc-bios/s390-ccw/virtio-scsi.c   |   1 +
>>>  pc-bios/s390-ccw/virtio.c        | 306 ++++-----------------------------
>>>  pc-bios/s390-ccw/virtio.h        |  46 ++---
>>>  roms/SLOF                        |   2 +-
>>>  16 files changed, 1011 insertions(+), 388 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
>>>
>>
>> Was going to apply but then I updated the slof thing but building fails. Not sure yet why.
>>
>> In file included from /home/cborntra/REPOS/qemu/roms/SLOF/lib/libc/ctype/isdigit.c:13:0:
>> /home/cborntra/REPOS/qemu/roms/SLOF/lib/libc/ctype/isdigit.c:15:17: error: expected ‘)’ before ‘ch’
>>  int isdigit(int ch)
> 
> What a bummer! Sorry, I've only cross-compiled the s390-ccw BIOS so far,
> and that worked fine (since s390x machines are a little bit hard to get
> here), but seems like there is still something ugly going on when you
> build the code natively ... likely somethings wrong in the Makefile ...
> I'll try to figure it out ...
> 
>  Thomas
> 

I haven't tried recently, but you could consider using one of these here
https://developer.ibm.com/linuxone/

-- 

Mit freundlichen Grüßen/Kind Regards
   Viktor Mihajlovski

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