Re: [Qemu-devel] [PATCH v2] vl.c: disallow command line fw cfg without opt/

[Gerd Hoffmann <kraxel@redhat.com>]

  Hi,

> Alternative: fail on:
> 
> - a blacklist of etc/* files including etc/system-states,
> etc/smbios/smbios-tables, etc/smbios/smbios-anchor,
> etc/reserved-memory-end, etc/pvpanic-port, etc/e820, and possibly
> etc/boot-menu-wait

I think that fails already because qemu throws an error on duplicate
firmware entries.

> Likewise SeaBIOS would switch from etc/ to an org.seabios/ prefix (for
> stuff usable from both Coreboot and QEMU, e.g.
> org.seabios/bootsplash.bmp) or org.qemu/ (for stuff that is specific to
> QEMU).

Do we really want shuffle around stuff like this?  It means we have to
support both paths in both firmware and qemu for a quite a while for
compatibility reasons.

(moving around opt/ovmf/ has this issue too, even though to a lesser
 extend as there isn't stuff as critical as acpi tables or boot order).

Also note that most stuff in etc/ is used by all firmwares, so moving
this to org.seabios looks pointless to me, especially as things might
change over time (i.e. ovmf starting to use cfg options it used to
ignore first, which is the case for etc/boot-menu-wait IIRC, so it
started as seabios only but isn't any more).

Also note that the fw_cfg layout is modeled a bit after cbfs (coreboot
filesystem) which is provided by coreboot and used by seabios.  That'll
cause trouble too if we try to redefine the paths.

cheers,
  Gerd