Re: Unable to single-step in kvm, always results in a resume

Jan Kiszka
2010-01-20T10:08:48Z

Hi Nicholas,

please don't drop CCs on reply.

Nicholas Amon wrote:
> Hi Jan,
>
> Thanks for responding. Yes, I am able to step instruction when I
> disable kvm w/ the no-kvm option. My host kernel is 64bit 2.6.27 and
> the program that I am debugging is 32 bit but starts in real mode. But
> the KVM module I am running is from kvm-88. Is there anyway I can check
> the version definitively?

kvm modules issue a message when being loaded, check your kernel log.
qemu-kvm gives you the version via -version.

OK, the problems you see is likely related to the very old versions you
use. Update to recent kvm-kmod (2.6.32 series) and qemu-kvm (0.12
series) and retry.

Jan

>
> Thanks,
>
> Nicholas
>
> Jan Kiszka wrote:
>> Jan Kiszka wrote:
>>
>>> Nicholas Amon wrote:
>>>
>>>> Hi All,
>>>>
>>>> I am trying to single-step through my kernel using qemu and kvm. I have
>>>> run qemu via: qemu-system-x86_64 -s -S -hda
>>>> /home/nickamon/lab1/obj/kernel.img and also connected to the process
>>>> using gdb.
>>>>
>>>> Problem is that whenever I try and step instruction, it seems to resume
>>>> my kernel rather than allowing me to progress instruction by
>>>> instruction. I have built the kvm snapshot from git and still no luck.
>>>> Tried following the code for a few hours and have no luck. Any
>>>> suggestions?
>>>>
>>> What's you host kernel or kvm-kmod version?
>>>
>>>
>> ...and does -no-kvm make any difference (except that it's much slower)?
>>
>> Jan