redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

i8k: Avoid lahf in 64-bit code 

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: stable@kernel.org
Cc: Massimo Dal Zotto <dz@debian.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
hifive-unleashed-5.1
Luca Tettamanti 2011-05-25 20:43:31 +02:00 committed by Jean Delvare
parent 4a7df24ddc
commit bc1f419c76
1 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
drivers/char/i8k.c
View File

@ -139,8 +139,8 @@ 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)