[Lguest] Loading Lguest guest - Unhandled trap 256 at x100000

[Naman Muley]

Hey Eviatar,

Thank you so much. I understand what i was doing.
I've attached a screenshot of the disassembly. But i did not understand "it
is very interesting to understand who generated it". how can you figure
that out from the binary disassembly?

Also, i did try read up on the unhandled trap, i found this:
http://wiki.debian.org/Lguest
and I understand why 256 is kind of odd because that interrupt number is
not covered by the host and so we send it as a valid number to the guest.
But the guest doesnt know how to handle this one.
But i have no idea what is causing this and how to remove this.

Any idea?

Naman


On Fri, Apr 26, 2013 at 4:33 PM, Eviatar Khen <eviatarkhen at gmail.com> wrote:

>  Hi Naman,
>
> I think what Ron meant was to disassembly of the kernel's image (vmlinux),
> not the Lguest binary (which is user space and does not generate directly
> interrupts).
> The guest crashes because the host got an invalid interrupt number, and it
> is very interesting to understand who generated it.
>
> Good luck,
>
> Eviatar
>
>
> On 04/26/2013 08:34 PM, Naman Muley wrote:
>
> Hey Ron,
>
>  Thanks for reaching out. I did the following( i am not sure if that's
> what you wanted me to do) :
>
>  objdump -D -b binary -m i386 Documentation/virtual/lguest/lguest  >
> /home/ngm7/disassembly.txt
> Following is the screenshot: Does that make sense ?
>
>  I had to take a screenshot because the disassembly.txt is inside the
> virtual machine. I'm working on ways to get that file out of the virtual
> machine.
>
> NOTE: the last line in the file was 6a1d. In the meanwhile, if you want to
> look at any specific line, let me know.
> I apologize for the raw kind of feedback.
>
>  Naman
>
>
>
>
> On Fri, Apr 26, 2013 at 11:45 AM, ron minnich <rminnich at gmail.com> wrote:
>
>> you might want to do a quick disassembly of the binary to see what's
>> at 0x100000. The 256 is (to me) kind of odd. So what's the start of
>> that image look like? Sorry, I'm rusty on lguest (i.e. I'm not Rusty)
>> so I'm not going to be as useful. But I would be curious to see the
>> disassembly.
>>
>> ron
>>
>
>
>
> _______________________________________________
> Lguest mailing listLguest at lists.ozlabs.orghttps://lists.ozlabs.org/listinfo/lguest
>
>
>
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