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    Subject[40/91] i8k: Avoid lahf in 64-bit code
    2.6.32-longterm review patch.  If anyone has any objections, please let us know.

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

    From: Luca Tettamanti <kronos.it@gmail.com>

    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 file changed, 2 insertions(+), 2 deletions(-)

    --- a/drivers/char/i8k.c
    +++ b/drivers/char/i8k.c
    @@ -138,8 +138,8 @@ static int i8k_smm(struct smm_regs *regs
    "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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