On Thu, 15.05.14 19:37, Matthew Garrett (mjg59(a)srcf.ucam.org) wrote:
On Thu, May 15, 2014 at 08:10:40PM +0200, Lennart Poettering wrote:
> On Thu, 15.05.14 18:33, Matthew Garrett (mjg59(a)srcf.ucam.org) wrote:
> >
> > I'm talking about the menu in the preferences pane inside OS X. The
> > spec's requirement that we use VFAT would break that.
>
> Well, having two ESPs, one in FAT, one in HFS+ is a blatant violation of
> EFI, and not what is done when windows is installed on a mac
> either... The pref panel doesn't really matter as there's a boot menu of
> the firmware you can use to boot your OSes.
Windows ends up with reduced access to the hardware. We do what OS X
does, not what Windows does, because that's the only way to get (for
example) working Thunderbolt.
You are not really suggesting that having a second HFS+ ESP in place is
what turns on Thunderbolt, are you?
> > Autodiscovery makes it impossible to pass additional
options to other
> > bootloaders. I don't think we care that much in general, but some users
> > may have requirements for it. It'd be nice to have a common format to
> > express that.
>
> If you want to pass aditional options, then add a manual drop-in for
> it. The BLS supports EFI binaries just fine. And for MBR chainloading
> there isn't any sane way to pass parameters anyway...
What's the objection to specifying a mechanism for chainloading?
Chainloading for MBR? Well, for starters, that there is no need for it,
and clearly legacy.
However, more importantly: one design decision of the BLS was to not
require cross-device links. We consciously avoided all the complexities
this involves, and will rely on the kernel having identified the
ESP/boot disk, from which we read what we need. Cross-device/partition
links always get nasty, require invention of a spefication language,
involving technology-specific identifiers... On EFI the device paths
generally are ignored if a partition UUID is included, since actually
checking the device path is so error prone and broken. And then trying
to come up with a scheme that works on both EFI and on MBR is just
intensly complex. Hence: we would rather not reference anything outside
of the immedaiety boot partition.
I really don't see why grub's native old config wasn't good enough for
that. THe BLS module I wrote for grub was supposed to be used in
combination with a fixed config file for any other windowses you might
have installed.
Lennart
--
Lennart Poettering, Red Hat