Messages in this thread | | | Date | Fri, 11 Oct 2013 08:53:57 -0700 | Subject | Re: [PATCH] partitions/efi: treat size mismatch as a warning, not an error | From | Doug Anderson <> |
| |
Karel,
On Fri, Oct 11, 2013 at 2:51 AM, Karel Zak <kzak@redhat.com> wrote: > On Thu, Oct 10, 2013 at 04:28:22PM -0700, Doug Anderson wrote: >> + * >> + * Consider a bad value here to be a warning to support dd-ing >> + * an image from a smaller disk to a bigger disk. >> */ >> if (ret == GPT_MBR_PROTECTIVE) { >> sz = le32_to_cpu(mbr->partition_record[part].size_in_lba); >> if (sz != (uint32_t) total_sectors - 1 && sz != 0xFFFFFFFF) >> - ret = 0; >> + pr_warn("%s: mbr size mismatch (%u != %u)\n", __func__, >> + sz, (uint32_t)((uint32_t) total_sectors - 1)); >> } > > I did the same change to util-linux v2.24 fdisk, so you can use the fdisk > to update your protective MBR and boot without warnings.
Yup, I think we've come up with a number of ways that we can update the partition table to avoid the problems. :) ...but the "feature" that used to work was being able to dd an image from a smaller disk onto a larger disk and have it "just boot" (though perhaps with some warning messages). This feature was used in the Chrome OS workflow to create bootable USB sticks / SD cards. We certainly could say that what the Chrome OS workflow is doing is illegal / bad / unethical, but it has been working for years and it would be nice for it to keep working if possible. :)
http://xkcd.com/1172/
-Doug
| |