From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Wed, 27 Jul 2011 18:16:44 +0200
From: Jan Kiszka <jan.kiszka@domain.hid>
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Subject: Re: [Xenomai-core] Debugging Xenomai kernel
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To: zenati <omar.zenati@domain.hid>
Cc: Xenomai core <Xenomai-core@domain.hid>

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?
Do you have a chance to test with a KVM host? It's faster anyway.

Jan

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