[syslinux] Very slow download with pxelinux > 4.07 on specific hardware

[Eric PEYREMORTE]

Le 12/03/2014 22:00, H. Peter Anvin a écrit :
> On 03/10/2014 04:15 PM, Gene Cumm wrote:
>> It's also a balance of time.  While working on 4.10-pre*/5.10-pre*, I
>> found that some hardware misreports its behavior.  "Sure, Interrupts
>> work" but they don't is but one that I worked around on specific
>> hardware.
>>
> The odd part is that people are reporting this even using the legacy PXE
> implementation (not lpxelinux.0)...
>
> 	-hpa
If there is a way to get useful debug traces let me know.

By the way, everything is slow from the moment the following string 
appears :

PXELINUX 5.10 0x5321850f

I tried to search through the code, compare different versions to 
understand what's wrong, but i definitely don't have the required skills....

What i notice from the wireshark traces, is that pxelinux.0 is loaded 
really quickly. Then it fetches ldlinux.c32 very slowly (for the next 
files too)

For lpxelinux.0, from the trace, everything is slow too, but at some 
point, the client seems stuck in a loop sending acknowledgement for a 
packet again and again. The server tries to send the next packet but the 
clients keeps sending ack for the previous one.

Eric