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post #26 of (permalink) Old 02-21-2014, 03:35 PM
achm3t
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Hi - I am trying to reproduce your success but I am having issues:

SYSTEM has 4GB

I am not able to reproduce the modifications you did, tried on GERMAN XP Professional SP3 Kernel.
The hexoffsets differ, if I try to modify the same address the resulting kernel will not boot.

I would like to understand how to determine the needed offsets for each possible ntkrpamp version using windbg, but I just don't know how to use it...

What am I trying to do?
Windows XP SP3 Pro german (ntkrpamp build5.1.2600.5512 as well as latest and greatest 5.1.2600.6419) do the >4GB patch
PAE-Kernel Multiprocessor (ntkrpamp)

I also have some halmacpi to play with:
from original SP1 (5.1.2600.1106) german
as well as newer german ones (inbetween SP1 and SP2) which might solve the USB problems you ran into (I would like to try that)
as well as german SP3 5.1.2600.5512
as well as english SP3 5.1.2600.5512


My problem is: I have absolutely no clue using Windbg. Do I have to do REMOTE debugging to set breakpoints?




I played a little more:

I thought when using ENGLISH SP3 files, it might actually work,
(the hex offsets are not the same in the german one (when I try to replace the same offsets in german as you did, the system won't boot)

So here is what I did:

System is still Windows XP SP3 GERMAN + almost latest patchlevel


I downloaded SP3 english and extracted ntkrpamp as well as halmacpi from it...

expanded english sp3 ntkrpamp.ex_ into sys32\ntkrnlpa.exe 5.1.2600.5512
expanded english sp3 halmacpi.dl_ into sys32\hal.dll 5.1.2600.5512

applied your fix to ntkrnlpa.exe
- hex editor offset 0x1B2A51 from
75 1B
to
90 90

fixed the checksum in pe-header of ntkrnlpa.exe

SFC is turned off, it won't replace the files with other ones - I doublechecked that!

rebootet the system - it starts (does NOT crash - even with eng sp3 halmacpi)

tried several boot.ini settings:
/fastdetect /noexecute=OptIn
-> PAE shown in system info (3,25GB) but is used for NX
TaskManager shows 3405932kb
this represents system default boot.ini

then I tried
/fastdetect /noexecute=OptIn /PAE
-> PAE shown in system info (3,25GB) but is used for NX
TaskManager shows 3405932kb
same result as default

then I tried
/fastdetect /noexecute=AlwaysOff /PAE
-> PAE IS shown in system info (3,25GB), NX options greyed out <-PM to Kondra states otherwise, I was wrong with that....
TaskManager still shows only 3405932kb


So everything works as if I had not applied the patch at all, doesn't it?....
What am I missing?
Why does this not work?

Afterwards I tried the same with german HALMACPI from SP1 5.1.2600.1106 (although from what I've read on this topic implies that downgrading halmacpi should only be necessary if new kernel does not boot up properly)
->old halmacpi german SP1 5.1.2600.1106 gives exactly the same results


Is it because I am using english kernel files within german xp?

I would love to patch my german kernel but I still don't understand how to use WinDbg...


Do you have any idea?
Is anybody able to do the necessary changes for ntkrpamp GERMAN SP3 5512 and/or latest and greatest (different hex-offsets are necessary)?

Has anybody successfully reproduced what Kondra achieved on any XP SP3?
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