Re: guest hardware breakpoint

[Jan Kiszka <jan.kiszka@siemens.com>]

Michael Le wrote:
> Hi,
> 
> I'm trying to set a hardware breakpoint inside the guest using gdb. This
> doesn't seem to work. Execution just skips right over it. I've have also
> tried writing some code to set a breakpoint by directly accessing the db
> registers from the guest. This also did not cause a breakpoint to be
> generated in the guest. Is it possible to use hardware breakpoints
> inside the guest? Is there some configuration that must be set in qemu
> or in the kvm modules?
> 
> The guest vm is running linux 2.6.18.
> 
> I'm using kvm-77 with linux kernel 2.6.27. I used the kvm kernel modules
> that came with the linux kernel and not from kvm-77. I have an x86
> machine. The command I use to run the vm is the following:
> 
> ../kvm/qemu-system-x86_64 main.img -m 512 -vnc :0

For now you need these patch queues for hw breakpoint support:

http://thread.gmane.org/gmane.comp.emulators.kvm.devel/22838
http://thread.gmane.org/gmane.comp.emulators.kvm.devel/22818

Dunno if they applied to -77, but I can provide rebases against latest
git on request.

Jan

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