On Thu, Feb 07, 2013 at 11:18:30AM +0100, Martin Wilck wrote: > Hello, > > you may have seen the following warning that is displayed when > someone tries to install GRUB2 on in a extX partition: > > "/sbin/grub-setup: warn: Embedding is not possible. GRUB can only be > installed in this setup by using blocklists. However, blocklists are > UNRELIABLE and their use is discouraged." This only happens if grub2 can't install itself in the space between the MBR and the beginning of the first partition. So in practice, most people won't see this unless they install the root partition on the whole disk, or perhaps for disks with GUUID partition tables. I think the grub2 developers are being far too paranoid. In practice, ext4 doesn't move blocks around. If you create a file and then mark the it as immutable, it should be pretty much safe. Yes, if you do an off-line shrink (or in some vary rare cases, an off-line resize2fs expand operation) it's possible that the file blocks might get moved, but that's a pretty rare case. There are some folks who are proposing that we use a bootloader inode: #define EXT2_BOOT_LOADER_INO 5 /* Boot loader inode */ for grub's benefit. It doesn't really make things any safer from a block relocation perspective, but maybe since it's "official", maybe it would make the grub2 developers feel better. But it's not something that has been terribly high priority, since it's basically more of a security blanket for the grub2 developers more than anything else.... - Ted -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
