[U-Boot] DHCP regression on 2009-06

[Robin Getz]

On Sun 12 Jul 2009 09:14, Michael Zaidman pondered:
> 
> On Fri, Jul 10, 2009 at 10:18 PM, Robin Getz <rgetz at blackfin.uclinux.org> 
wrote:
> 
> 
> On Fri 10 Jul 2009 12:27, Robin Getz pondered:
> > > 
http://git.denx.de/?p=u-boot/u-boot-net.git;a=commitdiff;h=3c172c4fdbbb5858fae38478d6399be4a16be3fc
> >
> > causes a regression on my network's DHCP server.
> > The part of the diff that causes the problem:
> >
> >  #if defined(CONFIG_CMD_DHCP)
> >
> >                 case DHCP:
> > -                       /* Start with a clean slate... */
> >                         BootpTry = 0;
> > -                       NetOurIP = 0;
> > -                       NetServerIP = getenv_IPaddr ("serverip");
> >                         DhcpRequest();      /* Basically same as BOOTP */
> >                         break;
> >
> > Since we are leaving the "NetOurIP" to whatever it was... The test at:
> > NetReceive():
> >
> >          case PROT_IP:
> >             [snip]
> >                 tmp = NetReadIP(&ip->ip_dst);
> >                 if (NetOurIP && tmp != NetOurIP && tmp != 0xFFFFFFFF) { 
> >                         return;
> >                 }
> >
> > Will return - (we leave the 'NetOurIP' set to the old value, the offered
> > address (what is in tmp) is not our's and tmp is not 0xFFFFFFFF).
> >
> > You never process the DHCP_OFFER...
> >
>  
> Did you try to remove the CONFIG_IPADDR from the board's config file?
> In this case the NetOurIP will get 0.  That should solve the problem.

No it does not - the problem occurs if you do dhcp, save, and then move to a 
different subnet, and a dhcp again (which is when I found it - recently moved 
offices, and needed new IP addresses for all my development systems)

As Wolfgang stated: the initial state (what CONFIG_IPADDR controls) doesn't 
change the issue that the bug exists - it just controls when the bug 
appears - sooner or later - but it is still there....

Rather than call BootpCheckPkt() as I suggested - Ben could just check the 
value of packetHandler... (if it is DhcpHandler, don't return)...



-Robin