Merge branch 'x86/nuke386' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull one final 386 removal patch from Peter Anvin.

IRQ 13 FPU error handling is gone.  That was not one of the proudest
moments in PC history.

* 'x86/nuke386' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, 386 removal: Remove support for IRQ 13 FPU error reporting

3 files changed, 1 insertions, 52 deletions

diff --git a/arch/x86/kernel/cpu/proc.c b/arch/x86/kernel/cpu/proc.c
index fbd895562292..3286a92e662a 100644
--- a/arch/x86/kernel/cpu/proc.c
+++ b/arch/x86/kernel/cpu/proc.c
@@ -26,11 +26,6 @@ static void show_cpuinfo_core(struct seq_file *m, struct cpuinfo_x86 *c,
 #ifdef CONFIG_X86_32
 static void show_cpuinfo_misc(struct seq_file *m, struct cpuinfo_x86 *c)
 {
-        /*
-         * We use exception 16 if we have hardware math and we've either seen
-         * it or the CPU claims it is internal
-         */
-        int fpu_exception = c->hard_math && (ignore_fpu_irq || cpu_has_fpu);
         seq_printf(m,
                    "fdiv_bug\t: %s\n"
                    "hlt_bug\t\t: %s\n"
@@ -45,7 +40,7 @@ static void show_cpuinfo_misc(struct seq_file *m, struct cpuinfo_x86 *c)
                    c->f00f_bug ? "yes" : "no",
                    c->coma_bug ? "yes" : "no",
                    c->hard_math ? "yes" : "no",
-                   fpu_exception ? "yes" : "no",
+                   c->hard_math ? "yes" : "no",
                    c->cpuid_level,
                    c->wp_works_ok ? "yes" : "no");
 }
diff --git a/arch/x86/kernel/irqinit.c b/arch/x86/kernel/irqinit.c
index 6e03b0d69138..7dc4e459c2b3 100644
--- a/arch/x86/kernel/irqinit.c
+++ b/arch/x86/kernel/irqinit.c
@@ -42,39 +42,6 @@
  * (these are usually mapped into the 0x30-0xff vector range)
  */
 
-#ifdef CONFIG_X86_32
-/*
- * Note that on a 486, we don't want to do a SIGFPE on an irq13
- * as the irq is unreliable, and exception 16 works correctly
- * (ie as explained in the intel literature). On a 386, you
- * can't use exception 16 due to bad IBM design, so we have to
- * rely on the less exact irq13.
- *
- * Careful.. Not only is IRQ13 unreliable, but it is also
- * leads to races. IBM designers who came up with it should
- * be shot.
- */
-
-static irqreturn_t math_error_irq(int cpl, void *dev_id)
-{
-        outb(0, 0xF0);
-        if (ignore_fpu_irq || !boot_cpu_data.hard_math)
-                return IRQ_NONE;
-        math_error(get_irq_regs(), 0, X86_TRAP_MF);
-        return IRQ_HANDLED;
-}
-
-/*
- * New motherboards sometimes make IRQ 13 be a PCI interrupt,
- * so allow interrupt sharing.
- */
-static struct irqaction fpu_irq = {
-        .handler = math_error_irq,
-        .name = "fpu",
-        .flags = IRQF_NO_THREAD,
-};
-#endif
-
 /*
  * IRQ2 is cascade interrupt to second interrupt controller
  */
@@ -242,13 +209,6 @@ void __init native_init_IRQ(void)
                 setup_irq(2, &irq2);
 
 #ifdef CONFIG_X86_32
-        /*
-         * External FPU? Set up irq13 if so, for
-         * original braindamaged IBM FERR coupling.
-         */
-        if (boot_cpu_data.hard_math && !cpu_has_fpu)
-                setup_irq(FPU_IRQ, &fpu_irq);
-
         irq_ctx_init(smp_processor_id());
 #endif
 }
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index eb8586693e0b..ecffca11f4e9 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -69,9 +69,6 @@
 
 asmlinkage int system_call(void);
 
-/* Do we ignore FPU interrupts ? */
-char ignore_fpu_irq;
-
 /*
  * The IDT has to be page-aligned to simplify the Pentium
  * F0 0F bug workaround.
@@ -564,9 +561,6 @@ void math_error(struct pt_regs *regs, int error_code, int trapnr)
 
 dotraplinkage void do_coprocessor_error(struct pt_regs *regs, long error_code)
 {
-#ifdef CONFIG_X86_32
-        ignore_fpu_irq = 1;
-#endif
         exception_enter(regs);
         math_error(regs, error_code, X86_TRAP_MF);
         exception_exit(regs);