usb_disk: invalid empty space size when creating MBR on new usb drive (120GB)

[kallisti5]

creating a new Intel partition map over a root file system with BFS results in a "unhandled ioctl 10102" and invalid data in DriveSetup.

see screenshots for examples and attached syslog

[kallisti5]

drive before Intel Partition Map

[kallisti5]

driver after Intel partition map

[kallisti5]

this failure situation can be reproduced by (sdd is your usb drive)

on a linux system...

sudo dd if=haiku-nightly.image of=/dev/sdd

Then trying to make an Intel partition map on the drive as per the screenshots above

[kallisti5]

syslog

[kallisti5]

this might be due to the TODO at haiku/src/add-ons/kernel/partitioning_systems/intel/write_support.cpp:987

// TODO: The partition is not supposed to be locked here!

Maybe as it is the raw device is a BFS partition it is locked? The code that writes the actual MBR section is pretty straight forward and doesn't care what in in the first 512 bytes of the drive.

[mmlr]

The ioctl translates to B_RAW_DEVICE_COMMAND and most probably has nothing to do with the event at hand. It is usually triggered by the TOC reading done by the cdda fs. The problem should happen regardless if you do that on a USB device nor not. As you already suggested it might be a locking problem or another disk device manger problem.