Re: [Qemu-devel] QEMU savevm RAM page offsets

[Juerg Haefliger]

On Tue, Aug 13, 2013 at 8:07 PM, Paolo Bonzini <address@hidden> wrote:
> Il 13/08/2013 19:52, Juerg Haefliger ha scritto:
>> I didn't mean to imply that the savevm format is broken and needed
>> fixing. I was just wondering if the data is there and I simply hadn't
>> found it. Upgrading QEMU is not an option at the moment since these
>> are tightly controlled productions machines. Is it possible to loadvm
>> a savevm file from 1.0 with 1.6 to then use guest-memory-dump?
>
> Yes, it should, but one important thing since 1.0 has been the merger of
> qemu-kvm and QEMU.  What distribution are you using?  I know Fedora
> allows qemu-kvm-1.0 to QEMU-1.6 compatibility, but I don't know about
> others.

Ubuntu 12.04


> Michael Tokarev is the maintainer of the Debian package, so he may be
> able to answer.
>
> Alternatively, you can modify your utility to simply add 512 MB to the
> addresses above 3.5 GB.

Is it really as simple as that? Isn't the OS (particularly Windows)
possibly doing some crazy remapping that needs to be taken into
account? meminfo on a VM with 4GB running Windows 2008 shows the
following:

C:\Users\Administrator\Desktop\MemInfo\amd64>MemInfo.exe -r
MemInfo v2.10 - Show PFN database information
Copyright (C) 2007-2009 Alex Ionescu
www.alex-ionescu.com

Physical Memory Range: 0000000000001000 to 000000000009B000 (154 pages, 616 KB)
Physical Memory Range: 0000000000100000 to 00000000DFFFD000 (917245
pages, 3668980 KB)
Physical Memory Range: 0000000100000000 to 0000000120000000 (131072
pages, 524288 KB)
MmHighestPhysicalPage: 1179648


...Juerg

> Paolo