On 08/20/2012 12:22 PM, Tejun Heo wrote:
Hello,
On Fri, Aug 17, 2012 at 04:10:52PM -0600, Stephen Warren wrote:
I was considering extending the kernel command-line option root=PARTUUID= to also support MBR (NT disk signatures). I was thinking of a syntax along the lines of:
root=PARTUUID=UUUUUUUU-PP[/PARTNROFF=%d]
... where UUUUUUUU is the hex representation of the NT disk signature, and PP is the hex representation of the partition number. Like GPT, /PARTNROFF could be used too if desired.
Related, I was thinking of changing struct partition_meta_info's uuid field to be a string, so that it could simply be strcmp'd against the UUID value on the kernel command-line. That way, the type of the UUID is irrelevant.
Does anyone have any objection to that?
Wouldn't that be able to break setups which work currently?
I don't believe so:
Since the newly supported UUID syntax wouldn't ever match any EFI UUID (the lengths differ in all cases), I don't believe the new syntax would affect behavior for any existing usage.
Obviously, part_efi.c would be modified to initialize struct partition_meta_info's uuid field to the appropriate string representation of the UUID so that the str(case)cmp would still succeed for existing command-lines. I ended up coding up that part of the change late Friday, and the feature was certainly still working OK.