[ 30/33] x86/alternatives: Fix p6 nops on non-modular kernels

From: Greg Kroah-Hartman
Date: Thu Oct 04 2012 - 17:28:27 EST


3.0-stable review patch. If anyone has any objections, please let me know.

------------------

From: Avi Kivity <avi@xxxxxxxxxx>

commit cb09cad44f07044d9810f18f6f9a6a6f3771f979 upstream.

Probably a leftover from the early days of self-patching, p6nops
are marked __initconst_or_module, which causes them to be
discarded in a non-modular kernel. If something later triggers
patching, it will overwrite kernel code with garbage.

Reported-by: Tomas Racek <tracek@xxxxxxxxxx>
Signed-off-by: Avi Kivity <avi@xxxxxxxxxx>
Cc: Michael Tokarev <mjt@xxxxxxxxxx>
Cc: Borislav Petkov <borislav.petkov@xxxxxxx>
Cc: Marcelo Tosatti <mtosatti@xxxxxxxxxx>
Cc: qemu-devel@xxxxxxxxxx
Cc: Anthony Liguori <anthony@xxxxxxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxxxxxxxx>
Cc: Alan Cox <alan@xxxxxxxxxxxxxxxxxxx>
Cc: Alan Cox <alan@xxxxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/5034AE84.90708@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Ben Jencks <ben@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/x86/kernel/alternative.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -161,7 +161,7 @@ static const unsigned char * const k7_no
#endif

#ifdef P6_NOP1
-static const unsigned char __initconst_or_module p6nops[] =
+static const unsigned char p6nops[] =
{
P6_NOP1,
P6_NOP2,


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