[syslinux] syslinux.efi with QEMU/OVMF

[BALATON Zoltan]

Hello,

I'm trying to find out how to pxe boot with syslinux.efi on QEMU with 
OVMF. After getting through the initial hurdle caused by the iPXE based 
option ROM included with QEMU having a problem as described in these 
threads:

http://www.syslinux.org/archives/2014-November/022804.html
http://sourceforge.net/p/edk2/mailman/message/33236100/

I'm now getting further to almost being able to boot but still not quite.

To eliminate further variables I'm now using the suggested virtio-net-pci 
with romfile= option to disable any iPXE code and only use code included 
in OVMF and syslinux.

Where I'm stuck now is that syslinux.efi fails when trying to download a 
file from http. This fails with the efi version but works with the same 
PXE/HTTP server and QEMU client not using OVMF and instead of syslinux.efi 
using lpxelinux.0. Looking at packet captures show that the connection is 
closed by the server after establishment with syslinux.efi.

This is the http connection with BIOS and lpxelinux.0:

TCP 49153 > http  [SYN] Seq=0 Win=64000 Len=0 MSS=1460
TCP  http > 49153 [SYN, ACK] Seq=0 Ack=1 Win=65535 Len=0 MSS=1460
TCP 49153 > http  [ACK] Seq=1 Ack=1 Win=64000 Len=0
HTTP GET /boot HTTP/1.0

with http transfer commencing normally after this, while with OVMF and 
syslinux.efi I get the following:

TCP 1654 > http [SYN] Seq=0 Win=65535 Len=0 MSS=1460 WS=64 TSval=1039 TSecr=0
TCP http > 1654 [SYN, ACK] Seq=0 Ack=1 Win=65535 Len=0 MSS=1460 WS=64 TSval=1151334911 TSecr=1039
TCP 1654 > http [ACK] Seq=1 Ack=1 Win=2097152 Len=0 TSval=1039 TSecr=0
TCP http > 1654 [RST] Seq=1 Win=0 Len=0
HTTP GET /boot HTTP/1.0

with data packets sent by the http server getting RST replies after this 
presumably due to socket closed in reply to the RST packet from the 
server. I see different options and values used in the EFI case but I 
don't know where these are coming from and if they are causing the 
problem. Does anyone have an understanding what happens or any hints what 
to look for?

If I try tftp instead it can transfer some files but is very slow (slower 
than it should be as it is faster with the BIOS version) and still cannot 
successfully boot with the transfer ending unexpectedly before finishing. 
(I saw similar reports on the mailing lists with HP and Dell hardware but 
I'm not sure they are related.)

Any help is greatly appreciated.

Regards,
BALATON Zoltan