x86_64, traps: Stop using IST for #SS

[pandora-kernel.git] / arch / x86 / kernel / traps.c

diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index e6fbb94..eacfa2f 100644 (file)
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -213,24 +213,12 @@ DO_ERROR(X86_TRAP_OLD_MF, SIGFPE, "coprocessor segment overrun",
                coprocessor_segment_overrun)
 DO_ERROR(X86_TRAP_TS, SIGSEGV, "invalid TSS", invalid_TSS)
 DO_ERROR(X86_TRAP_NP, SIGBUS, "segment not present", segment_not_present)
-#ifdef CONFIG_X86_32
 DO_ERROR(X86_TRAP_SS, SIGBUS, "stack segment", stack_segment)
-#endif
 DO_ERROR_INFO(X86_TRAP_AC, SIGBUS, "alignment check", alignment_check,
                BUS_ADRALN, 0)
 
 #ifdef CONFIG_X86_64
 /* Runs on IST stack */
-dotraplinkage void do_stack_segment(struct pt_regs *regs, long error_code)
-{
-       if (notify_die(DIE_TRAP, "stack segment", regs, error_code,
-                       X86_TRAP_SS, SIGBUS) == NOTIFY_STOP)
-               return;
-       preempt_conditional_sti(regs);
-       do_trap(X86_TRAP_SS, SIGBUS, "stack segment", regs, error_code, NULL);
-       preempt_conditional_cli(regs);
-}
-
 dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code)
 {
        static const char str[] = "double fault";
@@ -582,12 +570,13 @@ void __math_state_restore(struct task_struct *tsk)
        /* 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(
-               ASM_NOP8 ASM_NOP2,
-               "emms\n\t"              /* clear stack tags */
-               "fildl %P[addr]",       /* set F?P to defined value */
-               X86_FEATURE_FXSAVE_LEAK,
-               [addr] "m" (safe_address));
+       if (unlikely(static_cpu_has(X86_FEATURE_FXSAVE_LEAK))) {
+               asm volatile(
+                       "fnclex\n\t"
+                       "emms\n\t"
+                       "fildl %P[addr]"        /* set F?P to defined value */
+                       : : [addr] "m" (safe_address));
+       }
 
        /*
         * Paranoid restore. send a SIGSEGV if we fail to restore the state.
@@ -710,7 +699,7 @@ void __init trap_init(void)
        set_intr_gate(X86_TRAP_OLD_MF, &coprocessor_segment_overrun);
        set_intr_gate(X86_TRAP_TS, &invalid_TSS);
        set_intr_gate(X86_TRAP_NP, &segment_not_present);
-       set_intr_gate_ist(X86_TRAP_SS, &stack_segment, STACKFAULT_STACK);
+       set_intr_gate(X86_TRAP_SS, stack_segment);
        set_intr_gate(X86_TRAP_GP, &general_protection);
        set_intr_gate(X86_TRAP_SPURIOUS, &spurious_interrupt_bug);
        set_intr_gate(X86_TRAP_MF, &coprocessor_error);