Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Ingo Molnar:
 "Various low level fixes: fix more fallout from the FPU rework and the
  asm entry code rework, plus an MSI rework fix, and an idle-tracing fix"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/fpu/math-emu: Fix crash in fork()
  x86/fpu/math-emu: Fix math-emu boot crash
  x86/idle: Restore trace_cpu_idle to mwait_idle() calls
  x86/irq: Build correct vector mapping for multiple MSI interrupts
  Revert "sched/x86_64: Don't save flags on context switch"

arch/x86/include/asm/switch_to.h

@@ -79,12 +79,12 @@ do {									\
 #else /* CONFIG_X86_32 */
 
 /* frame pointer must be last for get_wchan */
-#define SAVE_CONTEXT    "pushq %%rbp ; movq %%rsi,%%rbp\n\t"
-#define RESTORE_CONTEXT "movq %%rbp,%%rsi ; popq %%rbp\t"
+#define SAVE_CONTEXT    "pushf ; pushq %%rbp ; movq %%rsi,%%rbp\n\t"
+#define RESTORE_CONTEXT "movq %%rbp,%%rsi ; popq %%rbp ; popf\t"
 
 #define __EXTRA_CLOBBER  \
 	, "rcx", "rbx", "rdx", "r8", "r9", "r10", "r11", \
-	  "r12", "r13", "r14", "r15", "flags"
+	  "r12", "r13", "r14", "r15"
 
 #ifdef CONFIG_CC_STACKPROTECTOR
 #define __switch_canary							  \
@@ -100,11 +100,7 @@ do {									\
 #define __switch_canary_iparam
 #endif	/* CC_STACKPROTECTOR */
 
-/*
- * There is no need to save or restore flags, because flags are always
- * clean in kernel mode, with the possible exception of IOPL.  Kernel IOPL
- * has no effect.
- */
+/* Save restore flags to clear handle leaking NT */
 #define switch_to(prev, next, last) \
 	asm volatile(SAVE_CONTEXT					  \
 	     "movq %%rsp,%P[threadrsp](%[prev])\n\t" /* save RSP */	  \

arch/x86/kernel/apic/vector.c

@@ -322,7 +322,7 @@ static int x86_vector_alloc_irqs(struct irq_domain *domain, unsigned int virq,
 		irq_data->chip = &lapic_controller;
 		irq_data->chip_data = data;
 		irq_data->hwirq = virq + i;
-		err = assign_irq_vector_policy(virq, irq_data->node, data,
+		err = assign_irq_vector_policy(virq + i, irq_data->node, data,
 					       info);
 		if (err)
 			goto error;

arch/x86/kernel/fpu/core.c

@@ -270,7 +270,7 @@ int fpu__copy(struct fpu *dst_fpu, struct fpu *src_fpu)
 	dst_fpu->fpregs_active = 0;
 	dst_fpu->last_cpu = -1;
 
-	if (src_fpu->fpstate_active)
+	if (src_fpu->fpstate_active && cpu_has_fpu)
 		fpu_copy(dst_fpu, src_fpu);
 
 	return 0;

arch/x86/kernel/fpu/init.c

@@ -40,6 +40,11 @@ static void fpu__init_cpu_generic(void)
 	write_cr0(cr0);
 
 	/* Flush out any pending x87 state: */
+#ifdef CONFIG_MATH_EMULATION
+	if (!cpu_has_fpu)
+		fpstate_init_soft(&current->thread.fpu.state.soft);
+	else
+#endif
 		asm volatile ("fninit");
 }
 

arch/x86/kernel/process.c

@@ -408,6 +408,7 @@ static int prefer_mwait_c1_over_halt(const struct cpuinfo_x86 *c)
 static void mwait_idle(void)
 {
 	if (!current_set_polling_and_test()) {
+		trace_cpu_idle_rcuidle(1, smp_processor_id());
 		if (this_cpu_has(X86_BUG_CLFLUSH_MONITOR)) {
 			smp_mb(); /* quirk */
 			clflush((void *)&current_thread_info()->flags);
@@ -419,6 +420,7 @@ static void mwait_idle(void)
 			__sti_mwait(0, 0);
 		else
 			local_irq_enable();
+		trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id());
 	} else {
 		local_irq_enable();
 	}