On 03/06/2012 11:13 AM, Keshav P R wrote:
On Tue, Mar 6, 2012 at 14:51, Jim Meyering<[email protected]> wrote:
Keshav P R wrote:
I also recommend changing
"boot" flag in parted for GPT disk to
something more meaningful like "uefisys". Many devs (of distro
installers) are confused as to how to set a partition as EFI SYSTEM
type in GPT disks and they do not know that "boot" in GPT disks sets a
partition as UEFISYS unlike the same flag in MBR disks.
https://bugzilla.redhat.com/show_bug.cgi?id=746895
Please give an example of precisely what you would like to change,
and how. If you are proposing to change only the input side of the UI,
(i.e., neither libparted, nor the output of parted) then adding an
alias might work.
I want to change the behaviour of the boot flag in GPT disks, or
eliminate the boot flag in GPT altogether, and replace it with uefisys
or a similar terminology, or alteast have uefisys as an extra flag for
setting UEFI SYSTEM type code, independent of "boot" flag. The uefisys
flag will also be useful for MBR disks since 0xEF MBR type is defined
for the uefisys partition.
IMHO, this is worth doing. A lot of words have been expended in online
forums describing the difference between the "boot flag" on GPT disks
vs. MBR disks. They're entirely unrelated concepts, and making them look
the same in the parted user interface is extremely confusing --
apparently not just to newbies, since OS installers get it wrong, too.
There *IS* a "legacy BIOS bootable" attribute in GPT (noted on the
Wikipedia page for GPT and in the EFI spec, IIRC) that's close to the
meaning of the MBR's "boot/active" flag. To the best of my knowledge,
only SYSLINUX's GPT boot loader uses this attribute, but at least
setting it incorrectly won't cause problems on EFI systems, as does
setting the ESP type code incorrectly.
Thus, IMHO the way to proceed is to change the current "boot" flag to
manage the "legacy BIOS bootable" attribute and create a new flag
("uefisys", "esp", or whatever) to set the ESP type code. Alternatively,
the "boot" flag could be removed and two new ones created, one for the
ESP type code and another for the "legacy BIOS bootable" attribute.
One potential problem with doing this is that existing installers,
scripts, etc., that DO use the "boot" flag correctly on GPT disks will
need to be modified. If they aren't, they'll break. IMHO, the long-term
gain is worth this short-term pain, but of course it's not my decision.
I could do this fix myself, but since my first parted patch has
languished for over eight months, I'm reluctant to invest more coding
time in the project.
--
Rod Smith
[email protected]
http://www.rodsbooks.com
