Re: Mapping between Host virtual address and guest physical address

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Muhui Jiang (jiangmuhui@gmail.com) wrote:
> Dear All
> 
> I am recently using qemu-system-arm to boot a linux uImage.
> 
> I would like to do some dynamic instrumentation on the uncompressed kernel.
> It seems that I need to focus on two key points.
> 
> Firstly, I need to know when the kernel is uncompressed, which means the
> compression process is finished. By analyzing the vmlinux.elf  and the
> trace I can figure it out.
> 
> Secondly, I need to know where the uncompressed is, which means where the
> uncompressed linux kernel (Before translated into tcg) stores in the
> virtual address of qemu. Does anyone have ideas? Many Thanks

There's are some existing HMP monitor commands for this type of
debugging:

gpa2hpa addr -- print the host physical address corresponding to a guest physical address
gpa2hva addr -- print the host virtual address corresponding to a guest physical address
gva2gpa addr -- print the guest physical address corresponding to a guest virtual address

so I think you're saying you want gpa2hva

Dave

> Regards
> Muhui
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK