x86, efi: Make "noefi" really disable EFI runtime serivces
authorMatt Fleming <matt.fleming@intel.com>
Wed, 20 Feb 2013 20:36:12 +0000 (20:36 +0000)
committerH. Peter Anvin <hpa@linux.intel.com>
Wed, 20 Feb 2013 21:18:36 +0000 (13:18 -0800)
commitfb834c7acc5e140cf4f9e86da93a66de8c0514da
tree3763a4af5de633bccf1f86fad24c3ef7440c2476
parent27cf929845b10043f2257693c7d179a9e0b1980e
x86, efi: Make "noefi" really disable EFI runtime serivces

commit 1de63d60cd5b ("efi: Clear EFI_RUNTIME_SERVICES rather than
EFI_BOOT by "noefi" boot parameter") attempted to make "noefi" true to
its documentation and disable EFI runtime services to prevent the
bricking bug described in commit e0094244e41c ("samsung-laptop:
Disable on EFI hardware"). However, it's not possible to clear
EFI_RUNTIME_SERVICES from an early param function because
EFI_RUNTIME_SERVICES is set in efi_init() *after* parse_early_param().

This resulted in "noefi" effectively becoming a no-op and no longer
providing users with a way to disable EFI, which is bad for those
users that have buggy machines.

Reported-by: Walt Nelson Jr <walt0924@gmail.com>
Cc: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1361392572-25657-1-git-send-email-matt@console-pimps.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
arch/x86/platform/efi/efi.c