[Fwd: Re: [syslinux] etherboot 5.3.14 and pxelinux keyboard problem]

[Michael Brown]

Tim Legge has passed the following message on to me:

hpa wrote:
> Quinn wrote:
> > Now it seems I have found a bug in PXELINUX with regards to etherboot.  
> > Up until 2.07 pxelinux was responsive to the keyboard.  From 2.08 and
> > up the keyboard is locked at the boot prompt when pxelinux is loaded
> > via etherboot 5.3.14.
>
> That would not be a PXELINUX bug, but an Etherboot bug.  The PXE READ
> UDP call is defined as non-blocking, but several implementors have
> screwed that one up (including VMWare.)  Unfortunately not answering
> ARPs has bad effects, too.

Etherboot's implementation of PXENV_UDP_READ is and has always been
non-blocking.  I don't see this problem when I try pxelinux from
syslinux-3.08-pre5 and current Etherboot CVS.  The relevant routine,
pxenv_udp_read() in Etherboot's core/pxe_export.c, hasn't changed since
July last year.

You can debug this by defining -DTRACE_PXE when compiling Etherboot.  This 
will show you a call trace such as 

Loading 10.254.254.2:pxelinux.0 ...(PXE).........done
[PXENV_GET_CACHED_INFO 2 to 00000800][PXENV_GET_CACHED_INFO 3 to 
00000800][PXENV_UDP_OPEN][PXENV_UDP_WRITE 40705->10.254.254.2:69 
(63)][PXENV_UDP_READ 10.254.254.2:32833->10.254.254.1:40705 
(19)][PXENV_UDP_WRITE 40706->10.254.254.2:69 (51)][PXENV_UDP_READ 
10.254.254.2:32833->10.254.254.1:40706 (19)][PXENV_UDP_WRITE 
40707->10.254.254.2:69 (50)] etc etc.

Please try compiling Etherboot with this option and send me the resulting
call trace from a run in which pxelinux ceases to respond to the keyboard.

I am not on this mailing list, so please Cc all replies to me.

Michael