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." Recently I have been involved in discussions about this on https://bugzilla.redhat.com/show_bug.cgi?id=872826. The Grub manual says "installing to a filesystem means that GRUB is vulnerable to its blocks being moved around by filesystem features such as tail packing, or even by aggressive fsck implementations". My question to the extX experts: Under what circumstances (except modifying, overwriting, deleting the bootloader image "core.img" itself) can a block list referencing "core.img" be corrupted? In particular: 1) could it happen during ordinary operation, filesystem code silently moving blocks around? 2) could it happen in an e2fsck run? 3) could it be caused by e4defrag? 4) could it happen with resize2fs even if the blocks occupied by the file fit in the size that the FS is resized to (otherwise obviously "yes")? 5) Anything else? 6) if the file was protected with the IMMUTABLE flag, would any of 1-5 still be able to corrupt the file? Regards Martin -- Dr. Martin Wilck PRIMERGY System Software Engineer x86 Server Engineering FUJITSU Fujitsu Technology Solutions GmbH Heinz-Nixdorf-Ring 1 33106 Paderborn, Germany Phone: ++49 5251 525 2796 Fax: ++49 5251 525 2820 Email: martin.wilck@xxxxxxxxxxxxxx Internet: http://ts.fujitsu.com Company Details: http://ts.fujitsu.com/imprint -- 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
