bugGNU GRUB - Bugs: bug #22138, GRUB doesn't support 4K sectors


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bug #22138: GRUB doesn't support 4K sectors

Submitted by:  John Klug <klugja>
Submitted on:  Sun Jan 27 16:47:31 2008  
Category: DocumentationSeverity: Major
Priority: 5 - NormalItem Group: None
Status: FixedPrivacy: Public
Assigned to: NoneOriginator Name: John Klug
Open/Closed: ClosedRelease: 1.95
Release: 1.98Reproducibility: None
Planned Release: None

Thu Aug 21 19:17:15 2008, comment #2:

This report is now half a year old, things are changing fast so please try current SVN

Felix Zielcke <fzielcke>
Project Member
Wed Jan 30 22:09:22 2008, comment #1:

1.95 is quite old. Please could you check if CVS still has this problem?

Robert Millan <robertmh>
Project Administrator
Sun Jan 27 16:47:31 2008, original submission:

As far as I can tell no level of grub (0.97 included) will work with logical 2048 byte sector size with USB. Shouldn't this be documented as a limitation?

I have two 2GB USB flash drives. One has 512 byte sector size, the other has 2048 byte sector sizes.

Here they were enumerated as /dev/sde (2048) and /dev/sdf (512):

# grub-install /dev/sdf
Installation finished. No error reported.
This is the contents of the device map /boot/grub/device.map.
Check if this is correct or not. If any of the lines is incorrect,
fix it and re-run the script `grub-install'.

(hd0) /dev/sde
(hd1) /dev/sdf
(chroot) livecd grub-1.95 # umount /dev/sdf1
(chroot) livecd grub-1.95 # mount /dev/sde1 /boot
(chroot) livecd grub-1.95 # grub-install /dev/sde
cannot find a GRUB drive for /dev/sde1.
Auto-detection of a filesystem module failed.
Please specify the module with the option `--modules' explicitly.

The OS does not need any special module to read the drive.

Here is what parted says about the drive that fails with grub (I have tried ext2, FAT32, and reiserfs):

# parted /dev/sde unit co print unit s print
Warning: Device /dev/sde has a logical sector size of 2048. Not all parts of
GNU Parted support this at the moment, and the working code is HIGHLY

Model: CBM Flash Disk (scsi)
Disk /dev/sde: 2041MB
Sector size (logical/physical): 2048B/512B
Partition Table: msdos

Number Start End Size Type File system Flags

Model: CBM Flash Disk (scsi)
Disk /dev/sde: 996607s
Sector size (logical/physical): 2048B/512B
Partition Table: msdos

# parted /dev/sdf1 unit co print unit s print
Model: Unknown (unknown)
Disk /dev/sdf1: 33.6MB
Sector size (logical/physical): 512B/512B
Partition Table: loop

Number Start End Size File system Flags
1 0.00B 33.6MB 33.6MB ext2

Model: Unknown (unknown)
Disk /dev/sdf1: 65535s
Sector size (logical/physical): 512B/512B
Partition Table: loop

Number Start End Size File system Flags
1 0s 65534s 65535s ext2

John Klug <klugja>


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Carbon-Copy List
  • -unavailable- added by phcoder (Updated the item)
  • -unavailable- added by fzielcke (Posted a comment)
  • -unavailable- added by robertmh (Posted a comment)
  • -unavailable- added by klugja (Submitted the item)
  • -unavailable- added by klugja (grub partition size limitation undocumented)

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    Follow 5 latest changes.

    Date Changed By Updated Field Previous Value => Replaced By
    Thu Jun 23 22:45:35 2011phcoderStatusNone=>Fixed
    Sat Oct 16 20:54:15 2010phcoderReleaseNone=>1.98
      SummaryGRUB partition size limitation undocumented=>GRUB doesn't support 4K sectors
    Sun Jan 27 16:47:31 2008klugjaCarbon-Copy-=>Added -unavailable-

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