Re: [Xenomai-core] Debugging Xenomai kernel

[zenati <omar.zenati@domain.hid>]

On 07/27/2011 06:16 PM, Jan Kiszka wrote:
> On 2011-07-27 18:13, zenati wrote:
>> On 07/27/2011 02:12 PM, Jan Kiszka wrote:
>>> On 2011-07-27 14:01, zenati wrote:
>>>> On 07/27/2011 11:23 AM, Jan Kiszka wrote:
>>>>> On 2011-07-26 13:54, zenati wrote:
>>>>>> Dear,
>>>>>>
>>>>>> I'm trying to debug Xenomai kernel with GDB and Qemu.
>>>>> QEMU in emulation or KVM mode?
>>>>>
>>>> I'm using Qemu in emulation mode.
>>> What's your target arch? x84-64, x86-32, or some ARM or PPC etc.
>> x86-32
>>>>>> So, I launch
>>>>>> Xenomai in Qemu and make it waiting for GDB. Then I start GDB and
>>>>>> connect them to Qemu, make breakpoint at the desired function to debug
>>>>>> and start Xenomai. If the function belongs to the linux kernel, the
>>>>>> execution stop at the breakpoint. But, if the function belongs to the
>>>>>> Xenomai nucleus, GDB recognize the breakpoint at the execution but don't
>>>>>> stop.
>>>>> Is Xenomai built as module or part of the main kernel image? The latter
>>>>> is simpler to handle as you don't have to deal with modules as symbol
>>>>> sources, find out their addresses, and load them at the right location.
>>>>>
>>>> Xenomai is built as a part of the main kernel.
>>> OK. Check during runtime of the guest if the disassembly at the desired
>>> breakpoint address matches the compiled code. Maybe there is some
>>> accidental discrepancy.
>> The breakpoints match correctly the compiled code. Anyway, it must stop
>> at the breakpoint. No?
> ...if the guest actually executes that address.
>
> I haven't used x86 QEMU in emulation mode for quite a while to debug
> something. Maybe we have a regression there. What's your QEMU version?
QEMU PC emulator version 0.12.3 (qemu-kvm-0.12.3), Copyright (c) 
2003-2008 Fabrice Bellard
> Do you have a chance to test with a KVM host? It's faster anyway.
I never used it before... But I'm ready to test it if there is no others 
ways to debug.
> Jan
>

Omar ZENATi