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

Pull x86 fixes from Ingo Molnar:
 "Misc fixes:

   - two microcode loader fixes

   - two FPU xstate handling fixes

   - an MCE timer handling related crash fix"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Make timer handling more robust
  x86/microcode: Do not access the initrd after it has been freed
  x86/fpu/xstate: Fix xcomp_bv in XSAVES header
  x86/fpu: Set the xcomp_bv when we fake up a XSAVES area
  x86/microcode/intel: Drop stashed AP patch pointer optimization

arch/x86/include/asm/microcode.h

@@ -140,6 +140,7 @@ extern void __init load_ucode_bsp(void);
 extern void load_ucode_ap(void);
 void reload_early_microcode(void);
 extern bool get_builtin_firmware(struct cpio_data *cd, const char *name);
+extern bool initrd_gone;
 #else
 static inline int __init microcode_init(void)			{ return 0; };
 static inline void __init load_ucode_bsp(void)			{ }

arch/x86/kernel/cpu/mcheck/mce.c

@@ -1373,20 +1373,15 @@ static unsigned long mce_adjust_timer_default(unsigned long interval)
 
 static unsigned long (*mce_adjust_timer)(unsigned long interval) = mce_adjust_timer_default;
 
-static void __restart_timer(struct timer_list *t, unsigned long interval)
+static void __start_timer(struct timer_list *t, unsigned long interval)
 {
 	unsigned long when = jiffies + interval;
 	unsigned long flags;
 
 	local_irq_save(flags);
 
-	if (timer_pending(t)) {
-		if (time_before(when, t->expires))
-			mod_timer(t, when);
-	} else {
-		t->expires = round_jiffies(when);
-		add_timer_on(t, smp_processor_id());
-	}
+	if (!timer_pending(t) || time_before(when, t->expires))
+		mod_timer(t, round_jiffies(when));
 
 	local_irq_restore(flags);
 }
@@ -1421,7 +1416,7 @@ static void mce_timer_fn(unsigned long data)
 
 done:
 	__this_cpu_write(mce_next_interval, iv);
-	__restart_timer(t, iv);
+	__start_timer(t, iv);
 }
 
 /*
@@ -1432,7 +1427,7 @@ void mce_timer_kick(unsigned long interval)
 	struct timer_list *t = this_cpu_ptr(&mce_timer);
 	unsigned long iv = __this_cpu_read(mce_next_interval);
 
-	__restart_timer(t, interval);
+	__start_timer(t, interval);
 
 	if (interval < iv)
 		__this_cpu_write(mce_next_interval, interval);
@@ -1779,17 +1774,15 @@ static void __mcheck_cpu_clear_vendor(struct cpuinfo_x86 *c)
 	}
 }
 
-static void mce_start_timer(unsigned int cpu, struct timer_list *t)
+static void mce_start_timer(struct timer_list *t)
 {
 	unsigned long iv = check_interval * HZ;
 
 	if (mca_cfg.ignore_ce || !iv)
 		return;
 
-	per_cpu(mce_next_interval, cpu) = iv;
-
-	t->expires = round_jiffies(jiffies + iv);
-	add_timer_on(t, cpu);
+	this_cpu_write(mce_next_interval, iv);
+	__start_timer(t, iv);
 }
 
 static void __mcheck_cpu_setup_timer(void)
@@ -1806,7 +1799,7 @@ static void __mcheck_cpu_init_timer(void)
 	unsigned int cpu = smp_processor_id();
 
 	setup_pinned_timer(t, mce_timer_fn, cpu);
-	mce_start_timer(cpu, t);
+	mce_start_timer(t);
 }
 
 /* Handle unconfigured int18 (should never happen) */
@@ -2566,7 +2559,7 @@ static int mce_cpu_dead(unsigned int cpu)
 
 static int mce_cpu_online(unsigned int cpu)
 {
-	struct timer_list *t = &per_cpu(mce_timer, cpu);
+	struct timer_list *t = this_cpu_ptr(&mce_timer);
 	int ret;
 
 	mce_device_create(cpu);
@@ -2577,13 +2570,13 @@ static int mce_cpu_online(unsigned int cpu)
 		return ret;
 	}
 	mce_reenable_cpu();
-	mce_start_timer(cpu, t);
+	mce_start_timer(t);
 	return 0;
 }
 
 static int mce_cpu_pre_down(unsigned int cpu)
 {
-	struct timer_list *t = &per_cpu(mce_timer, cpu);
+	struct timer_list *t = this_cpu_ptr(&mce_timer);
 
 	mce_disable_cpu();
 	del_timer_sync(t);

arch/x86/kernel/cpu/microcode/amd.c

@@ -384,6 +384,7 @@ void load_ucode_amd_ap(unsigned int family)
 reget:
 		if (!get_builtin_microcode(&cp, family)) {
 #ifdef CONFIG_BLK_DEV_INITRD
+			if (!initrd_gone)
 				cp = find_cpio_data(ucode_path, (void *)initrd_start,
 						    initrd_end - initrd_start, NULL);
 #endif

arch/x86/kernel/cpu/microcode/core.c

@@ -46,6 +46,8 @@
 static struct microcode_ops	*microcode_ops;
 static bool dis_ucode_ldr = true;
 
+bool initrd_gone;
+
 LIST_HEAD(microcode_cache);
 
 /*
@@ -190,21 +192,24 @@ void load_ucode_ap(void)
 static int __init save_microcode_in_initrd(void)
 {
 	struct cpuinfo_x86 *c = &boot_cpu_data;
+	int ret = -EINVAL;
 
 	switch (c->x86_vendor) {
 	case X86_VENDOR_INTEL:
 		if (c->x86 >= 6)
-			return save_microcode_in_initrd_intel();
+			ret = save_microcode_in_initrd_intel();
 		break;
 	case X86_VENDOR_AMD:
 		if (c->x86 >= 0x10)
-			return save_microcode_in_initrd_amd(c->x86);
+			ret = save_microcode_in_initrd_amd(c->x86);
 		break;
 	default:
 		break;
 	}
 
-	return -EINVAL;
+	initrd_gone = true;
+
+	return ret;
 }
 
 struct cpio_data find_microcode_in_initrd(const char *path, bool use_pa)
@@ -247,9 +252,16 @@ struct cpio_data find_microcode_in_initrd(const char *path, bool use_pa)
 	 * has the virtual address of the beginning of the initrd. It also
 	 * possibly relocates the ramdisk. In either case, initrd_start contains
 	 * the updated address so use that instead.
+	 *
+	 * initrd_gone is for the hotplug case where we've thrown out initrd
+	 * already.
 	 */
-	if (!use_pa && initrd_start)
+	if (!use_pa) {
+		if (initrd_gone)
+			return (struct cpio_data){ NULL, 0, "" };
+		if (initrd_start)
 			start = initrd_start;
+	}
 
 	return find_cpio_data(path, (void *)start, size, NULL);
 #else /* !CONFIG_BLK_DEV_INITRD */

arch/x86/kernel/cpu/microcode/intel.c

@@ -41,7 +41,7 @@
 
 static const char ucode_path[] = "kernel/x86/microcode/GenuineIntel.bin";
 
-/* Current microcode patch used in early patching */
+/* Current microcode patch used in early patching on the APs. */
 struct microcode_intel *intel_ucode_patch;
 
 static inline bool cpu_signatures_match(unsigned int s1, unsigned int p1,
@@ -607,12 +607,6 @@ int __init save_microcode_in_initrd_intel(void)
 	struct ucode_cpu_info uci;
 	struct cpio_data cp;
 
-	/*
-	 * AP loading didn't find any microcode patch, no need to save anything.
-	 */
-	if (!intel_ucode_patch || IS_ERR(intel_ucode_patch))
-		return 0;
-
 	if (!load_builtin_intel_microcode(&cp))
 		cp = find_microcode_in_initrd(ucode_path, false);
 
@@ -628,7 +622,6 @@ int __init save_microcode_in_initrd_intel(void)
 	return 0;
 }
 
-
 /*
  * @res_patch, output: a pointer to the patch we found.
  */

arch/x86/kernel/fpu/core.c

@@ -9,6 +9,7 @@
 #include <asm/fpu/regset.h>
 #include <asm/fpu/signal.h>
 #include <asm/fpu/types.h>
+#include <asm/fpu/xstate.h>
 #include <asm/traps.h>
 
 #include <linux/hardirq.h>
@@ -183,7 +184,8 @@ void fpstate_init(union fpregs_state *state)
 	 * it will #GP. Make sure it is replaced after the memset().
 	 */
 	if (static_cpu_has(X86_FEATURE_XSAVES))
-		state->xsave.header.xcomp_bv = XCOMP_BV_COMPACTED_FORMAT;
+		state->xsave.header.xcomp_bv = XCOMP_BV_COMPACTED_FORMAT |
+					       xfeatures_mask;
 
 	if (static_cpu_has(X86_FEATURE_FXSR))
 		fpstate_init_fxstate(&state->fxsave);