[syslinux] syslinux.efi with QEMU/OVMF

[Laszlo Ersek]

On 04/09/15 01:24, BALATON Zoltan wrote:
> On Tue, 7 Apr 2015, Laszlo Ersek wrote:
>> Whereas syslinux.efi apparently uses the embedded gpxe/ tree, and that
>> one uses TCP timestamps. See tcp_xmit() in gpxe/src/net/tcp.c:
> 
> Actually syslinux.efi seems to be using the implementation calling into
> UEFI via these functions:
> 
> http://git.kernel.org/cgit/boot/syslinux/syslinux.git/tree/efi/tcp.c
> 
> I've tried to add debug messages to these functions and got the following:
> 
> core_tcp_connect: connecting
> core_tcp_connect: connected
> core_tcp_connect: at out: closing CompletionToken
> core_tcp_write: Sending 227 bytes
> tcp transmit failed, Access Denied
> 
> Meanwhile on the OVMF side I could get these debug logs:
> 
> Tcb (3F296898) state TCP_CLOSED --> TCP_SYN_SENT
> TcpToSendData: set RTT measure sequence 464107706 for TCB 3F296898
> Tcb (3F296898) state TCP_SYN_SENT --> TCP_ESTABLISHED
> TcpComputeRtt: new RTT for TCB 3F296898 computed SRTT: 0 RTTVAR: 0 RTO: 5
> TcpInput: connection established for TCB 3F296898 in SYN_SENT
> TcpInput: connection reset for TCB 3F296898
> Tcb (3F296898) state TCP_ESTABLISHED --> TCP_CLOSED
> Tcb (3F296898) state TCP_CLOSED --> TCP_CLOSED
> 
> So now it seems the problem may be in OVMF somewhere but how to find it?
> EDK2 code is hard to follow and I'm not sure what should I look for. Any
> hints?

Those messages are from "NetworkPkg/TcpDxe/TcpOutput.c".

OvmfPkg/README has a section called "Build Scripts".

Thanks
Laszlo