Cannot add new efi boot entry

[Jiri Slaby <jslaby-AlSwsSmVLrQ@public.gmane.org>]

Hi,

after update to 3.8, every update of the kernel ends up in an unbootable
machine. It is due to the following commit:
commit 68d929862e29a8b52a7f2f2f86a0600423b093cd
Author: Matthew Garrett <matthew.garrett-05XSO3Yj/JvQT0dZR+AlfA@public.gmane.org>
Date:   Sat Mar 2 19:40:17 2013 -0500

    efi: be more paranoid about available space when creating variables

efibootmgr which tries to add an entry and silently fails when writing
to /sys/firmware/efi/vars/new_var with -ENOSPC.

There are many entries in there:
# efibootmgr
BootCurrent: 000D
Timeout: 0 seconds
BootOrder:
0018,0000,0001,0002,0003,0007,0008,0009,000A,000B,000C,000D,000E,000F,0010,0011,0012
Boot0000  Setup
Boot0001  Boot Menu
Boot0002  Diagnostic Splash Screen
Boot0003  Lenovo Diagnostics
Boot0004  Startup Interrupt Menu
Boot0005  ME Configuration Menu
Boot0006  Rescue and Recovery
Boot0007* USB CD
Boot0008* USB FDD
Boot0009* ATAPI CD0
Boot000A* ATA HDD0
Boot000B* ATA HDD1
Boot000C* ATA HDD2
Boot000D* USB HDD
Boot000E* PCI LAN
Boot000F* ATAPI CD1
Boot0010  Other CD
Boot0011* ATA HDD3
Boot0012  Other HDD
Boot0013* IDER BOOT CDROM
Boot0014* IDER BOOT Floppy
Boot0015* ATA HDD
Boot0016* ATAPI CD:
Boot0017* PCI LAN
Boot0018* Linux


Remaining size is about 20k, added entry size is hundreds bytes, store
size is 64k.

Obviously lowering the limitation from 1/2 to 1/4 fixes the problem for
me because it always worked on my setup to store a new entry...

Any ideas how to overcome that? It would be better to blacklist bad
machines rather than whitelist good ones, right?

thanks,
-- 
js
suse labs