[ros-dev] Severe bug found: Freeldr passes wrong disk geometry to ntoskrnl.exe and disk.sys

[Eric Kohl]

Hi!

I just found a severe bug in hardware detection code of Freeldr. It uses 
two configuration nodes in the hardware tree to pass information about 
detected hard-disks to ntoskrnl.exe and disk.sys.

First, hard-disk information is passed as a DiskPeripheral node attached 
to a DiskController node.

Second, hard-disk information is passed as an array of 
CM_INT13_DRIVE_PARAMETER entries in a special system configuration node, 
if the disks were detected by the BIOS.

As part of the boot process, the special system configuration node is 
used by disk.sys to determine the disk geometry used by the BIOS. 
Unfortunately, this configuration node did not use the extended disk 
geometry (LBA geometry) but the old CHS geometry even if the LBA 
geometry was available.

I already fixed this bug in my local source tree and suddenly Freeldr, 
disk.sys and usetup.exe report exactly the same disk geometry as gparted 
(http://gparted.sourceforge.net/download.php). Unfortunately, using this 
patch breaks the 2nd stage setup.

I will provide a patch that fixes the Freeldr issue as soon as I have 
cleaned up the source tree.

Please help me find the remaining bug or workaround that keeps ReactOS 
from booting into 2nd stage setup! I guess it is either part of usetup 
or somewhere in the partition management routines.


Regards,
Eric