linux-sg2042/arch/x86/platform
Satoru Takeuchi 1de63d60cd efi: Clear EFI_RUNTIME_SERVICES rather than EFI_BOOT by "noefi" boot parameter
There was a serious problem in samsung-laptop that its platform driver is
designed to run under BIOS and running under EFI can cause the machine to
become bricked or can cause Machine Check Exceptions.

    Discussion about this problem:
    https://bugs.launchpad.net/ubuntu-cdimage/+bug/1040557
    https://bugzilla.kernel.org/show_bug.cgi?id=47121

    The patches to fix this problem:
    efi: Make 'efi_enabled' a function to query EFI facilities
    83e6818974

    samsung-laptop: Disable on EFI hardware
    e0094244e4

Unfortunately this problem comes back again if users specify "noefi" option.
This parameter clears EFI_BOOT and that driver continues to run even if running
under EFI. Refer to the document, this parameter should clear
EFI_RUNTIME_SERVICES instead.

Documentation/kernel-parameters.txt:
===============================================================================
...
	noefi		[X86] Disable EFI runtime services support.
...
===============================================================================

Documentation/x86/x86_64/uefi.txt:
===============================================================================
...
- If some or all EFI runtime services don't work, you can try following
  kernel command line parameters to turn off some or all EFI runtime
  services.
	noefi		turn off all EFI runtime services
...
===============================================================================

Signed-off-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Link: http://lkml.kernel.org/r/511C2C04.2070108@jp.fujitsu.com
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-02-13 17:24:11 -08:00
..
ce4100 TTY/Serial merge for 3.8-rc1 2012-12-11 14:08:47 -08:00
efi efi: Clear EFI_RUNTIME_SERVICES rather than EFI_BOOT by "noefi" boot parameter 2013-02-13 17:24:11 -08:00
geode arch/x86/platform/geode/net5501.c: change active_low to 0 for LED driver 2012-05-04 14:40:07 -07:00
iris arch/x86/platform/iris/iris.c: register a platform device and a platform driver 2012-12-18 15:02:11 -08:00
mrst X86: drivers: remove __dev* attributes. 2013-01-03 15:57:04 -08:00
olpc X86: drivers: remove __dev* attributes. 2013-01-03 15:57:04 -08:00
scx200 X86: drivers: remove __dev* attributes. 2013-01-03 15:57:04 -08:00
sfi Merge branch 'linus' into x86/apic-cleanups 2011-01-07 14:14:15 +01:00
uv arch/x86/platform/uv: Fix incorrect tlb flush all issue 2013-01-24 15:58:54 +01:00
visws x86/apic: Fix typo EIO_ACK -> EOI_ACK and document it 2012-05-18 09:46:07 +02:00
Makefile x86: geode: New PCEngines Alix system driver 2011-09-21 11:19:42 +02:00