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Subject[PATCH 89/91] i8k: Avoid lahf in 64-bit code
2.6.27-longterm review patch.  If anyone has any objections, please let us know.

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

commit bc1f419c76a2d6450413ce4349f4e4a07be011d5 upstream.

i8k uses lahf to read the flag register in 64-bit code; early x86-64
CPUs, however, lack this instruction and we get an invalid opcode
exception at runtime.
Use pushf to load the flag register into the stack instead.

Signed-off-by: Luca Tettamanti <kronos.it@gmail.com>
Reported-by: Jeff Rickman <jrickman@myamigos.us>
Tested-by: Jeff Rickman <jrickman@myamigos.us>
Tested-by: Harry G McGavran Jr <w5pny@arrl.net>
Cc: Massimo Dal Zotto <dz@debian.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
drivers/char/i8k.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)

Index: longterm-2.6.27/drivers/char/i8k.c
===================================================================
--- longterm-2.6.27.orig/drivers/char/i8k.c 2012-02-05 22:34:47.136914619 +0100
+++ longterm-2.6.27/drivers/char/i8k.c 2012-02-05 22:34:47.574914836 +0100
@@ -138,8 +138,8 @@
"movl %%edi,20(%%rax)\n\t"
"popq %%rdx\n\t"
"movl %%edx,0(%%rax)\n\t"
- "lahf\n\t"
- "shrl $8,%%eax\n\t"
+ "pushfq\n\t"
+ "popq %%rax\n\t"
"andl $1,%%eax\n"
:"=a"(rc)
: "a"(regs)



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