Patch "x86, efi: Make "noefi" really disable EFI runtime serivces" has been added to the 3.4-stable tree

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This is a note to let you know that I've just added the patch titled

    x86, efi: Make "noefi" really disable EFI runtime serivces

to the 3.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     x86-efi-make-noefi-really-disable-efi-runtime-serivces.patch
and it can be found in the queue-3.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.


>From fb834c7acc5e140cf4f9e86da93a66de8c0514da Mon Sep 17 00:00:00 2001
From: Matt Fleming <matt.fleming@xxxxxxxxx>
Date: Wed, 20 Feb 2013 20:36:12 +0000
Subject: x86, efi: Make "noefi" really disable EFI runtime serivces

From: Matt Fleming <matt.fleming@xxxxxxxxx>

commit fb834c7acc5e140cf4f9e86da93a66de8c0514da upstream.

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@xxxxxxxxx>
Cc: Satoru Takeuchi <takeuchi_satoru@xxxxxxxxxxxxxx>
Signed-off-by: Matt Fleming <matt.fleming@xxxxxxxxx>
Link: http://lkml.kernel.org/r/1361392572-25657-1-git-send-email-matt@xxxxxxxxxxxxxxxxx
Signed-off-by: H. Peter Anvin <hpa@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 arch/x86/platform/efi/efi.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -84,9 +84,10 @@ int efi_enabled(int facility)
 }
 EXPORT_SYMBOL(efi_enabled);
 
+static bool disable_runtime = false;
 static int __init setup_noefi(char *arg)
 {
-	clear_bit(EFI_RUNTIME_SERVICES, &x86_efi_facility);
+	disable_runtime = true;
 	return 0;
 }
 early_param("noefi", setup_noefi);
@@ -733,7 +734,7 @@ void __init efi_init(void)
 	if (!efi_is_native())
 		pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
 	else {
-		if (efi_runtime_init())
+		if (disable_runtime || efi_runtime_init())
 			return;
 		set_bit(EFI_RUNTIME_SERVICES, &x86_efi_facility);
 	}


Patches currently in stable-queue which might be from matt.fleming@xxxxxxxxx are

queue-3.4/x86-make-sure-we-can-boot-in-the-case-the-bda-contains-pure-garbage.patch
queue-3.4/x86-efi-make-noefi-really-disable-efi-runtime-serivces.patch
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