Re: [PATCH v3 1/2] init: add root=PARTUUID=UUID/PARTNROFF=%d support

["H. Peter Anvin" <hpa@zytor.com>]

On 06/30/2011 02:10 PM, Will Drewry wrote:
> Expand root=PARTUUID=UUID syntax to support selecting a root partition
> by integer offset from a known, unique partition.  This approach
> provides similar properties to specifying a device and partition number,
> but using the UUID as the unique path prior to evaluating the offset.
> 
> For example,
>   root=PARTUUID=99DE9194-FC15-4223-9192-FC243948F88B/PARTNROFF=1
> selects the partition with UUID 99DE.. then select the next
> partition.
> 
> This change is motivated by a particular usecase in Chromium OS where
> the bootloader can easily determine what partition it is on (by UUID)
> but doesn't perform general partition table walking.
> 
> That said, support for this model provides a direct mechanism for the
> user to modify the root partition to boot without specifically needing
> to extract each UUID or update the bootloader explicitly when the root
> partition UUID is changed (if it is recreated to be larger, for
> instance).  Pinning to a /boot-style partition UUID allows the arbitrary
> root partition reconfiguration/modifications with slightly less
> ambiguity than just [dev][partition] and less stringency than the
> specific root partition UUID.
> 

Obklibcsnark:

Does anyone still doubt that as long as this kind of code exists in the
kernel that it will not get continually added to?

	-hpa