Re: 2.4.32: unresolved symbol unregister_qdisc

["Randy.Dunlap" <rdunlap@xenotime.net>]

On Sun, 9 Apr 2006 22:49:50 -0400 (EDT) George P Nychis wrote:

> 
> > On Sun, 9 Apr 2006 22:05:33 -0400 (EDT) George P Nychis wrote:
> > 
> >> 
> >>> On Sun, 9 Apr 2006 13:37:25 -0400 (EDT) George P Nychis wrote:
> >>> 
> >>>> Thanks for the help.
> >>>> 
> >>>> Here is the makefile: http://rafb.net/paste/results/auchPH75.html
> >>>> 
> >>>> And here is the full errors I receive: 
> >>>> http://rafb.net/paste/results/Qplpqw74.html
> >>>> 
> >>>> Greatly appreciate it
> >>>> 
> >>>> - George
> >>> 
> >>> [repeat: please don't top-post]
> >>> 
> >>> I don't know how much I can help you.  It's been a long time since
> >>> I've built external modules on 2.4.x.
> >>> 
> >>> Problems that I see: - the Makefile does not use the expected 2.4
> >>> kernel build infrastructure; - kernel Makefile uses -nostdinc to
> >>> prevent use of userspace headers; - Makefile is trying to include
> >>> userspace headers instead of kernel headers, e.g.: In file included
> >>> from /usr/include/linux/if_ether.h:107, from
> >>> /usr/include/linux/netdevice.h:29, from sch_xcp.c:8: - this specified
> >>> include directory is only in 2.6.x, not 2.4.x: -I/lib/modules/`uname
> >>> -r`/build/include/asm/mach-default
> >>> 
> >>> It's not clear to me how this makefile could work with 2.4.x at all.
> >>> Is it supposed to, or that's just what you want to see it do?
> >>> 
> >>> You could try to fix the Makefile based on makefile-changes articles
> >>> at lwn.net. E.g.: http://lwn.net/Articles/151784/ 
> >>> http://lwn.net/Articles/79984/ http://lwn.net/Articles/74767/ 
> >>> http://lwn.net/Articles/69148/ http://lwn.net/Articles/21823/
> >>> 
> >>> 
> >>> 
> >>>>> On Sat, 8 Apr 2006 19:18:47 -0400 (EDT) George P Nychis wrote:
> >>>>> 
> >>>>>> Yeah, this module is unfortunately not under the GPL, it was
> >>>>>> made for research and i am not the author, I was only given the
> >>>>>> code for my own research.
> >>>>>> 
> >>>>>> I enabled that support in the kernel, and then tried to
> >>>>>> recompile and get tons of errors/warnings... so maybe I am
> >>>>>> missing something else to be enabled in the kernel... here are a
> >>>>>> few examples of errors: /usr/include/linux/skbuff.h:30:26:
> >>>>>> net/checksum.h: No such file or directory
> >>>>>> /usr/include/asm/irq.h:16:25: irq_vectors.h: No such file or
> >>>>>> directory /usr/include/linux/irq.h:72: error: `NR_IRQS' 
> >>>>>> undeclared here (not in a function)
> >>>>>> /usr/include/asm/hw_irq.h:28: error: `NR_IRQ_VECTORS' undeclared
> >>>>>> here (not in a function)
> >>>>>> 
> >>>>>> I think those are the top most errors, so if i can fix those 
> >>>>>> hopefully the rest shall vanish!
> >>>>> 
> >>>>> Looks like a Makefile problem then.  Can you post the Makefile? 
> >>>>> Hopefully it is using a Makefile and not just an elaborate gcc
> >>>>> command line.
> >>>>> 
> >>>>> [and please don't top-post]
> >>>>> 
> >>>>>> - George
> >>>>>> 
> >>>>>> 
> >>>>>>> From: "George P Nychis" <gnychis@cmu.edu> Date: Sat, 8 Apr
> >>>>>>> 2006 18:47:34 -0400 (EDT)
> >>>>>>> 
> >>>>>>>> Hey,
> >>>>>>>> 
> >>>>>>>> I have a kernel module that uses unregister_qdisc and 
> >>>>>>>> register_qdisc, whenever i try to insert the module I get: 
> >>>>>>>> /lib/modules/2.4.32/kernel/net/sched/sch_xcp.o: 
> >>>>>>>> /lib/modules/2.4.32/kernel/net/sched/sch_xcp.o: unresolved 
> >>>>>>>> symbol unregister_qdisc 
> >>>>>>>> /lib/modules/2.4.32/kernel/net/sched/sch_xcp.o: 
> >>>>>>>> /lib/modules/2.4.32/kernel/net/sched/sch_xcp.o: unresolved 
> >>>>>>>> symbol register_qdisc
> >>>>>>>> 
> >>>>>>>> Am i missing some sort of support in the kernel?
> >>>>>>> 
> >>>>>>> Make sure CONFIG_NET_SCHED is enabled and that you compiled
> >>>>>>> your module against that kernel.
> >>>>>>> 
> >>>>>>> Where does this sch_xcp come from?  It's not in the vanilla 
> >>>>>>> sources.
> >>>>>>> 
> >>>>>>> Also, please direct networking questions to the 
> >>>>>>> netdev@vger.kernel.org mailing list which I have added to the
> >>>>>>>  CC:.
> >>> 
> >>> --- ~Randy
> >>> 
> >>> 
> >> 
> >> By the way, if I add -I/usr/src/linux/include to the compile line, it
> >> successfully compiles, however, i am back to the start: lanthanum-ini
> >> src-1.0.1 # insmod sch_xcp Using
> >> /lib/modules/2.4.32/kernel/net/sched/sch_xcp.o 
> >> /lib/modules/2.4.32/kernel/net/sched/sch_xcp.o:
> >> /lib/modules/2.4.32/kernel/net/sched/sch_xcp.o: unresolved symbol
> >> unregister_qdisc /lib/modules/2.4.32/kernel/net/sched/sch_xcp.o:
> >> /lib/modules/2.4.32/kernel/net/sched/sch_xcp.o: unresolved symbol
> >> register_qdisc
> > 
> > Yet your 2.4.32 kernel image file does have those symbols in it? Can you
> > verify that by using 'nm' on the kernel image file?
> > 
> > If so, then I suppose that you'll need to make a small module test case 
> > that exhibits this behavior, or just tell us where to get the sch_xcp
> > files...
> > 
> > (re-added cc: for netdev)
> > 
> > --- ~Randy
> > 
> > 
> 
> By kernel image, do you mean /usr/src/linux/vmlinux ?
> if so,
> lanthanum-ini linux # nm vmlinux | grep register_qdisc
> c0399200 R __kstrtab_register_qdisc
> c0399240 R __kstrtab_unregister_qdisc
> c039ebc8 R __ksymtab_register_qdisc
> c039ebd0 R __ksymtab_unregister_qdisc
> c02eda40 T register_qdisc
> c02edaf0 T unregister_qdisc

Yes.  That's good, then.

---
~Randy