Re: [Xenomai-help] Almost running - kernel BUG in add_preempt_count at kernel/sched.c:2819!

[Philippe Gerum <rpm@xenomai.org>]

Jan Kiszka wrote:
> Gary Wallace wrote:
> 
>>  My story is the same as Jim's except I used 2.6.16.6 and a gcc 3.3.3
>>cross compiler.  The ipipe patch applies just fine after the motorola
>>patch.  Building with ipipe disabled results in a kernel that boots
>>and runs just fine.  When ipipe is enabled, I sometimes get the error
>>Jim received, sometimes the kernel just hangs.  There is never a stack
>>trace on the console.  I've tried ipipe versions 1.2-01, 1.2-03,
>>1.3-00, 1.3-02, and 1.3-03, all with the same results (either the
>>kernel hangs or I get the kernel BUG error).
>>
>>  I haven't been able to get the board to boot without using the
>>motorola patch.
>>
>>  I have tried building with ipipe-tracer, but this results in compile
>>errors (the tracer patch applies just fine).  Here are the compile
>>errors when ipipe-tracer is enabled:
>>
>># make
>>  CHK     include/linux/version.h
>>  CHK     include/linux/compile.h
>>  CHK     usr/initramfs_list
>>  UIMAGE  arch/ppc/boot/images/uImage
>>"mkimage" command not found - U-Boot images will not be built
>>  Image: arch/ppc/boot/images/uImage not made
>>  AS      arch/ppc/boot/simple/head.o
>>  AS      arch/ppc/boot/simple/relocate.o
>>  CC      arch/ppc/boot/simple/misc.o
>>  CC      arch/ppc/boot/simple/misc-mv64x60.o
>>powerpc-750-linux-gnu-objcopy -O elf32-powerpc \
>>        --add-section=.image=arch/ppc/boot/images/vmlinux.gz \
>>        --set-section-flags=.image=contents,alloc,load,readonly,data \
>>        arch/ppc/boot/simple/dummy.o arch/ppc/boot/simple/image.o
>>powerpc-750-linux-gnu-ld -T /usr/src/linux-2.6.14.6-ppc/arch/ppc/boot/ld.script -Ttext 0x00800000 -Bstatic -o arch/ppc/boot/simple/zvmlinux arch/ppc/boot/simple/head.o arch/ppc/boot/simple/relocate.o arch/ppc/boot/simple/misc.o arch/ppc/boot/simple/misc-mv64x60.o arch/ppc/boot/simple/image.o arch/ppc/boot/common/lib.a arch/ppc/boot/lib/lib.a
>>arch/ppc/boot/simple/misc.o(.text+0x10): In function `get_mem_size':
>>arch/ppc/boot/simple/misc.c:87: undefined reference to `_mcount'
>>arch/ppc/boot/simple/misc.o(.text+0x54): In function `decompress_kernel':
>>arch/ppc/boot/simple/misc.c:93: undefined reference to `_mcount'
>>arch/ppc/boot/simple/misc.o(.text+0x4b8): In function `board_isa_init':
>>arch/ppc/boot/simple/misc.c:274: undefined reference to `_mcount'
>>arch/ppc/boot/simple/misc.o(.text+0x4f8): In function `load_kernel':
>>arch/ppc/boot/simple/misc.c:281: undefined reference to `_mcount'
>>arch/ppc/boot/simple/misc-mv64x60.o(.text+0x10): In function `mv64360_get_mem_size':
>>arch/ppc/boot/simple/misc-mv64x60.c:31: undefined reference to `_mcount'
>>arch/ppc/boot/simple/misc-mv64x60.o(.text+0xbc):arch/ppc/boot/simple/misc-mv64x60.c:51: more undefined references to `_mcount' follow
>>make[2]: *** [arch/ppc/boot/simple/zvmlinux] Error 1
>>make[1]: *** [simple] Error 2
>>make: *** [zImage] Error 2
>># 
>>
> 
> 
> Philippe, can you comment on this? I do not have an PPC build
> environment at hand.
>

I can't reproduce it here, but that does not mean much, since I can't 
select the same setup anyway, due to the missing patch. Is the file 
arch/ppc/ipipe-mcount.S listed as being compiled during the kernel build?

> @Gary: Do you get the same error without the Motorola patch?
> 


-- 

Philippe.