Re: GAG bootloader cannot boot from an ext4 partition



On 19/09/2011 01:06, David W. Hodgins wrote:
On Sun, 18 Sep 2011 13:20:37 -0400, Maurice Batey
<maurice@xxxxxxxxxxxxxxxxx> wrote:

the root partition had to be formatted ext4.
When my GAG boot loader tried to boot from that root partition,
it was unable do so.

What version of gag are you using? I'm using gag and ext4 root
partitions (/boot is on /).

Without rebooting to check, according to my downloads folder, I'm
using 4.10.

Regards, Dave Hodgins


If gag is reading the partition as though it were ext2, then it /might/ work with ext4. There are only a few additions to ext4 that cause it to look different from ext2 from a read-only viewpoint (you don't want to mount it read-write as ext2, because you'll get issues with the transaction log, directory indexes, etc.). The big one that I know of is extents - these are used in ext4 to make file allocation much more efficient, but are incomprehensible to an ext2/3 driver. If your ext4 filesystem has extents disabled, or none of the directories or files needed for booting happen to use extents (maybe they are small files, maybe you got lucky), then you are okay.

.



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