Re: Broken common.rmk change

[David Miller]

From: Vladimir '$B&U(B-coder/phcoder' Serbinenko <address@hidden>
Date: Mon, 07 Dec 2009 11:48:07 +0100

> The problem actually is the following:
> When we're in OS we know the OS device name but not the firmware device
> name. So we're able to generate correct root= for kernel command line
> but can only guess which names you would need for grub's set root=. The
> solution we're going for is to have UUID of fs stored in grub.cfg and go
> through all partitions on boot and find the right one nd set it to root
> variable. As for passing root= kernel parameter the decision of using
> device name or UUID= is based on heuristics (sigh) but you can disable
> them altogether in /etc/default/grub:
> 
> # Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to
> Linux
> #GRUB_DISABLE_LINUX_UUID=true

UUIDs are convenient but can be very time consuming.

Some sparc64 systems come with 10 or 20 block OpenFirmware device
aliases, and we're going probe all of them, one by one, to look for
the UUID.

The firmware device name is so trivially obtainable, especially on
ieee1275.  That's what the grub-ofpathname tool I wrote does on
sparc64.  And it's what the 'ofpathname' script used by powerpc on
grub does as well.