Hi All
i've ubuntu8.10 kernel 2.6.27 installed in my system.
I've to debug the kernel using kgdb, for that i searched on net and found that kgdb is avaliaible only for 2.6.15 kernel source.
so i downloaded 2.6.15 kernel source and did everything to compile it (i used the config file from the kernel installed in my machine having kernel 2.6.27)but in the compilatoin it is giving me the error:

include/asm/mpspec_def.h:78: warning: packed attribute ignored for field of type unsigned char[6]
arch/i386/kernel/apic.c: In function smp_apic_timer_interrupt:
arch/i386/kernel/apic.c:1136: sorry, unimplemented: inlining failed in call to smp_local_timer_interrupt: function body not available
arch/i386/kernel/apic.c:1205: sorry, unimplemented: called from here
make[1]: *** [arch/i386/kernel/apic.o] Error 1
make: *** [arch/i386/kernel] Error 2

Please suggest me how should i proceed for kernel debugging

Thanks
Ankush

when the kernel was configured kdbg has to be enabled. then build it is in every kernel. you must if you copy a config file from. you can use an older kerenl config and for a newer kernel do a make oldconfig then it will ask you to configure the new stuff on the kernel. But the 2.6.25 kernel and a 2.6.27 kernel has some changes . so you can't use a newer kernel config for a older kernel.. make mrproper make config or make oldconfig now go make and do a make gconfig and it will open up the kernel navagate to the enable kernel debuging =y now build it install it and now you can debug all you want.

check the gcc version. I guess you are using gcc 4.x.
GCC 3.4.6 would work.

kgdb was merged at 2.6.26 ISTR. Don't know about Hardy, but it shows as selected in the Intrepid config.
A grep against the Hardy config for KGDB might save a lot of angst.

Edit: there is a docbook in the kernel source tree for kgdb.