aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--arch/x86/include/asm/i387.h13
1 files changed, 7 insertions, 6 deletions
diff --git a/arch/x86/include/asm/i387.h b/arch/x86/include/asm/i387.h
index 0b20bbb758f2..cb42fad1f6fd 100644
--- a/arch/x86/include/asm/i387.h
+++ b/arch/x86/include/asm/i387.h
@@ -242,12 +242,13 @@ clear_state:
/* AMD K7/K8 CPUs don't save/restore FDP/FIP/FOP unless an exception
is pending. Clear the x87 state here by setting it to fixed
values. safe_address is a random variable that should be in L1 */
- alternative_input(
- GENERIC_NOP8 GENERIC_NOP2,
- "emms\n\t" /* clear stack tags */
- "fildl %[addr]", /* set F?P to defined value */
- X86_FEATURE_FXSAVE_LEAK,
- [addr] "m" (safe_address));
+ if (unlikely(boot_cpu_has(X86_FEATURE_FXSAVE_LEAK))) {
+ asm volatile(
+ "fnclex\n\t"
+ "emms\n\t"
+ "fildl %[addr]" /* set F?P to defined value */
+ : : [addr] "m" (safe_address));
+ }
end:
task_thread_info(tsk)->status &= ~TS_USEDFPU;
}