x86 fixes

index a89fdbc1f0be..03663740c866 100644
@@ -421,7 +421,7 @@ __visible long do_fast_syscall_32(struct pt_regs *regs)
 	regs->ip = landing_pad;
 
 	/*
-	 * Fetch ECX from where the vDSO stashed it.
+	 * Fetch EBP from where the vDSO stashed it.
 	 *
 	 * WARNING: We are in CONTEXT_USER and RCU isn't paying attention!
 	 */

@@ -432,10 +432,10 @@ __visible long do_fast_syscall_32(struct pt_regs *regs)
 		 * Micro-optimization: the pointer we're following is explicitly
 		 * 32 bits, so it can't be out of range.
 		 */
-		__get_user(*(u32 *)&regs->cx,
+		__get_user(*(u32 *)&regs->bp,
 			    (u32 __user __force *)(unsigned long)(u32)regs->sp)
 #else
-		get_user(*(u32 *)&regs->cx,
+		get_user(*(u32 *)&regs->bp,
 			 (u32 __user __force *)(unsigned long)(u32)regs->sp)
 #endif
 		) {

index e4f8010f22e0..f7ba9fbf12ee 100644
@@ -216,6 +216,7 @@
 #define X86_FEATURE_PAUSEFILTER ( 8*32+13) /* AMD filtered pause intercept */
 #define X86_FEATURE_PFTHRESHOLD ( 8*32+14) /* AMD pause filter threshold */
 #define X86_FEATURE_VMMCALL     ( 8*32+15) /* Prefer vmmcall to vmcall */
+#define X86_FEATURE_XENPV       ( 8*32+16) /* "" Xen paravirtual guest */
 
 
 /* Intel-defined CPU features, CPUID level 0x00000007:0 (ebx), word 9 */

index 10d0596433f8..c759b3cca663 100644
@@ -19,6 +19,12 @@ static inline int paravirt_enabled(void)
 	return pv_info.paravirt_enabled;
 }
 
+static inline int paravirt_has_feature(unsigned int feature)
+{
+	WARN_ON_ONCE(!pv_info.paravirt_enabled);
+	return (pv_info.features & feature);
+}
+
 static inline void load_sp0(struct tss_struct *tss,
 			     struct thread_struct *thread)
 {

index 31247b5bff7c..3d44191185f8 100644
@@ -70,9 +70,14 @@ struct pv_info {
 #endif
 
 	int paravirt_enabled;
+	unsigned int features;	  /* valid only if paravirt_enabled is set */
 	const char *name;
 };
 
+#define paravirt_has(x) paravirt_has_feature(PV_SUPPORTED_##x)
+/* Supported features */
+#define PV_SUPPORTED_RTC        (1<<0)
+
 struct pv_init_ops {
 	/*
 	 * Patch may replace one of the defined code sequences with

index 67522256c7ff..2d5a50cb61a2 100644
@@ -472,6 +472,7 @@ static inline unsigned long current_top_of_stack(void)
 #else
 #define __cpuid			native_cpuid
 #define paravirt_enabled()	0
+#define paravirt_has(x) 	0
 
 static inline void load_sp0(struct tss_struct *tss,
 			    struct thread_struct *thread)

index 38dd5efdd04c..2bd2292a316d 100644
@@ -193,20 +193,17 @@ static int __init numachip_system_init(void)
 	case 1:
 		init_extra_mapping_uc(NUMACHIP_LCSR_BASE, NUMACHIP_LCSR_SIZE);
 		numachip_apic_icr_write = numachip1_apic_icr_write;
-		x86_init.pci.arch_init = pci_numachip_init;
 		break;
 	case 2:
 		init_extra_mapping_uc(NUMACHIP2_LCSR_BASE, NUMACHIP2_LCSR_SIZE);
 		numachip_apic_icr_write = numachip2_apic_icr_write;
-
-		/* Use MCFG config cycles rather than locked CF8 cycles */
-		raw_pci_ops = &pci_mmcfg;
 		break;
 	default:
 		return 0;
 	}
 
 	x86_cpuinit.fixup_cpu_id = fixup_cpu_id;
+	x86_init.pci.arch_init = pci_numachip_init;
 
 	return 0;
 }

index c5b0d562dbf5..7e8a736d09db 100644
@@ -999,6 +999,17 @@ void do_machine_check(struct pt_regs *regs, long error_code)
 	int flags = MF_ACTION_REQUIRED;
 	int lmce = 0;
 
+	/* If this CPU is offline, just bail out. */
+	if (cpu_is_offline(smp_processor_id())) {
+		u64 mcgstatus;
+
+		mcgstatus = mce_rdmsrl(MSR_IA32_MCG_STATUS);
+		if (mcgstatus & MCG_STATUS_RIPV) {
+			mce_wrmsrl(MSR_IA32_MCG_STATUS, 0);
+			return;
+		}
+	}
+
 	ist_enter(regs);
 
 	this_cpu_inc(mce_exception_count);

index cd9685235df9..4af8d063fb36 100644
@@ -200,6 +200,9 @@ static __init int add_rtc_cmos(void)
 	}
 #endif
 
+	if (paravirt_enabled() && !paravirt_has(RTC))
+		return -ENODEV;
+
 	platform_device_register(&rtc_device);
 	dev_info(&rtc_device.dev,
 		 "registered platform RTC device (no PNP device found)\n");

index a0d09f6c6533..a43b2eafc466 100644
@@ -1414,6 +1414,7 @@ __init void lguest_init(void)
 	pv_info.kernel_rpl = 1;
 	/* Everyone except Xen runs with this set. */
 	pv_info.shared_kernel_pmd = 1;
+	pv_info.features = 0;
 
 	/*
 	 * We set up all the lguest overrides for sensitive operations.  These

index 5774800ff583..b7de78bdc09c 100644
@@ -1192,7 +1192,7 @@ static const struct pv_info xen_info __initconst = {
 #ifdef CONFIG_X86_64
 	.extra_user_64bit_cs = FLAT_USER_CS64,
 #endif
-
+	.features = 0,
 	.name = "Xen",
 };
 

@@ -1535,6 +1535,8 @@ asmlinkage __visible void __init xen_start_kernel(void)
 
 	/* Install Xen paravirt ops */
 	pv_info = xen_info;
+	if (xen_initial_domain())
+		pv_info.features |= PV_SUPPORTED_RTC;
 	pv_init_ops = xen_init_ops;
 	pv_apic_ops = xen_apic_ops;
 	if (!xen_pvh_domain()) {

@@ -1886,8 +1888,10 @@ EXPORT_SYMBOL_GPL(xen_hvm_need_lapic);
 
 static void xen_set_cpu_features(struct cpuinfo_x86 *c)
 {
-	if (xen_pv_domain())
+	if (xen_pv_domain()) {
 		clear_cpu_bug(c, X86_BUG_SYSRET_SS_ATTRS);
+		set_cpu_cap(c, X86_FEATURE_XENPV);
+	}
 }
 
 const struct hypervisor_x86 x86_hyper_xen = {