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

Pull perf fixes from Ingo Molnar:
 "Misc fixes plus a small hw-enablement patch for Intel IB model 58
  uncore events"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel/lbr: Demand proper privileges for PERF_SAMPLE_BRANCH_KERNEL
  perf/x86/intel/lbr: Fix LBR filter
  perf/x86: Blacklist all MEM_*_RETIRED events for Ivy Bridge
  perf: Fix vmalloc ring buffer pages handling
  perf/x86/intel: Fix unintended variable name reuse
  perf/x86/intel: Add support for IvyBridge model 58 Uncore
  perf/x86/intel: Fix typo in perf_event_intel_uncore.c
  x86: Eliminate irq_mis_count counted in arch_irq_stat

arch/x86/kernel/cpu/perf_event_intel.c

@@ -128,10 +128,15 @@ static struct event_constraint intel_ivb_event_constraints[] __read_mostly =
 	INTEL_UEVENT_CONSTRAINT(0x08a3, 0x4), /* CYCLE_ACTIVITY.CYCLES_L1D_PENDING */
 	INTEL_UEVENT_CONSTRAINT(0x0ca3, 0x4), /* CYCLE_ACTIVITY.STALLS_L1D_PENDING */
 	INTEL_UEVENT_CONSTRAINT(0x01c0, 0x2), /* INST_RETIRED.PREC_DIST */
-	INTEL_EVENT_CONSTRAINT(0xd0, 0xf), /* MEM_UOPS_RETIRED.* */
-	INTEL_EVENT_CONSTRAINT(0xd1, 0xf), /* MEM_LOAD_UOPS_RETIRED.* */
-	INTEL_EVENT_CONSTRAINT(0xd2, 0xf), /* MEM_LOAD_UOPS_LLC_HIT_RETIRED.* */
-	INTEL_EVENT_CONSTRAINT(0xd3, 0xf), /*  MEM_LOAD_UOPS_LLC_MISS_RETIRED.* */
+	/*
+	 * Errata BV98 -- MEM_*_RETIRED events can leak between counters of SMT
+	 * siblings; disable these events because they can corrupt unrelated
+	 * counters.
+	 */
+	INTEL_EVENT_CONSTRAINT(0xd0, 0x0), /* MEM_UOPS_RETIRED.* */
+	INTEL_EVENT_CONSTRAINT(0xd1, 0x0), /* MEM_LOAD_UOPS_RETIRED.* */
+	INTEL_EVENT_CONSTRAINT(0xd2, 0x0), /* MEM_LOAD_UOPS_LLC_HIT_RETIRED.* */
+	INTEL_EVENT_CONSTRAINT(0xd3, 0x0), /* MEM_LOAD_UOPS_LLC_MISS_RETIRED.* */
 	EVENT_CONSTRAINT_END
 };
 

arch/x86/kernel/cpu/perf_event_intel_lbr.c

@@ -310,7 +310,7 @@ void intel_pmu_lbr_read(void)
  * - in case there is no HW filter
  * - in case the HW filter has errata or limitations
  */
-static void intel_pmu_setup_sw_lbr_filter(struct perf_event *event)
+static int intel_pmu_setup_sw_lbr_filter(struct perf_event *event)
 {
 	u64 br_type = event->attr.branch_sample_type;
 	int mask = 0;
@@ -318,8 +318,11 @@ static void intel_pmu_setup_sw_lbr_filter(struct perf_event *event)
 	if (br_type & PERF_SAMPLE_BRANCH_USER)
 		mask |= X86_BR_USER;
 
-	if (br_type & PERF_SAMPLE_BRANCH_KERNEL)
+	if (br_type & PERF_SAMPLE_BRANCH_KERNEL) {
+		if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN))
+			return -EACCES;
 		mask |= X86_BR_KERNEL;
+	}
 
 	/* we ignore BRANCH_HV here */
 
@@ -339,6 +342,8 @@ static void intel_pmu_setup_sw_lbr_filter(struct perf_event *event)
 	 * be used by fixup code for some CPU
 	 */
 	event->hw.branch_reg.reg = mask;
+
+	return 0;
 }
 
 /*
@@ -386,7 +391,9 @@ int intel_pmu_setup_lbr_filter(struct perf_event *event)
 	/*
 	 * setup SW LBR filter
 	 */
-	intel_pmu_setup_sw_lbr_filter(event);
+	ret = intel_pmu_setup_sw_lbr_filter(event);
+	if (ret)
+		return ret;
 
 	/*
 	 * setup HW LBR filter, if any
@@ -442,8 +449,18 @@ static int branch_type(unsigned long from, unsigned long to)
 			return X86_BR_NONE;
 
 		addr = buf;
-	} else
-		addr = (void *)from;
+	} else {
+		/*
+		 * The LBR logs any address in the IP, even if the IP just
+		 * faulted. This means userspace can control the from address.
+		 * Ensure we don't blindy read any address by validating it is
+		 * a known text address.
+		 */
+		if (kernel_text_address(from))
+			addr = (void *)from;
+		else
+			return X86_BR_NONE;
+	}
 
 	/*
 	 * decoder needs to know the ABI especially

arch/x86/kernel/cpu/perf_event_intel_uncore.c

@@ -3093,7 +3093,7 @@ static void __init uncore_types_exit(struct intel_uncore_type **types)
 static int __init uncore_type_init(struct intel_uncore_type *type)
 {
 	struct intel_uncore_pmu *pmus;
-	struct attribute_group *events_group;
+	struct attribute_group *attr_group;
 	struct attribute **attrs;
 	int i, j;
 
@@ -3120,19 +3120,19 @@ static int __init uncore_type_init(struct intel_uncore_type *type)
 		while (type->event_descs[i].attr.attr.name)
 			i++;
 
-		events_group = kzalloc(sizeof(struct attribute *) * (i + 1) +
-					sizeof(*events_group), GFP_KERNEL);
-		if (!events_group)
+		attr_group = kzalloc(sizeof(struct attribute *) * (i + 1) +
+					sizeof(*attr_group), GFP_KERNEL);
+		if (!attr_group)
 			goto fail;
 
-		attrs = (struct attribute **)(events_group + 1);
-		events_group->name = "events";
-		events_group->attrs = attrs;
+		attrs = (struct attribute **)(attr_group + 1);
+		attr_group->name = "events";
+		attr_group->attrs = attrs;
 
 		for (j = 0; j < i; j++)
 			attrs[j] = &type->event_descs[j].attr.attr;
 
-		type->events_group = events_group;
+		type->events_group = attr_group;
 	}
 
 	type->pmu_group = &uncore_pmu_attr_group;
@@ -3545,11 +3545,12 @@ static int __init uncore_cpu_init(void)
 		msr_uncores = nhm_msr_uncores;
 		break;
 	case 42: /* Sandy Bridge */
+	case 58: /* Ivy Bridge */
 		if (snb_uncore_cbox.num_boxes > max_cores)
 			snb_uncore_cbox.num_boxes = max_cores;
 		msr_uncores = snb_msr_uncores;
 		break;
-	case 45: /* Sandy Birdge-EP */
+	case 45: /* Sandy Bridge-EP */
 		if (snbep_uncore_cbox.num_boxes > max_cores)
 			snbep_uncore_cbox.num_boxes = max_cores;
 		msr_uncores = snbep_msr_uncores;

arch/x86/kernel/irq.c

@@ -165,10 +165,6 @@ u64 arch_irq_stat_cpu(unsigned int cpu)
 u64 arch_irq_stat(void)
 {
 	u64 sum = atomic_read(&irq_err_count);
-
-#ifdef CONFIG_X86_IO_APIC
-	sum += atomic_read(&irq_mis_count);
-#endif
 	return sum;
 }
 

kernel/events/ring_buffer.c

@@ -326,11 +326,16 @@ void rb_free(struct ring_buffer *rb)
 }
 
 #else
+static int data_page_nr(struct ring_buffer *rb)
+{
+	return rb->nr_pages << page_order(rb);
+}
 
 struct page *
 perf_mmap_to_page(struct ring_buffer *rb, unsigned long pgoff)
 {
-	if (pgoff > (1UL << page_order(rb)))
+	/* The '>' counts in the user page. */
+	if (pgoff > data_page_nr(rb))
 		return NULL;
 
 	return vmalloc_to_page((void *)rb->user_page + pgoff * PAGE_SIZE);
@@ -350,10 +355,11 @@ static void rb_free_work(struct work_struct *work)
 	int i, nr;
 
 	rb = container_of(work, struct ring_buffer, work);
-	nr = 1 << page_order(rb);
+	nr = data_page_nr(rb);
 
 	base = rb->user_page;
-	for (i = 0; i < nr + 1; i++)
+	/* The '<=' counts in the user page. */
+	for (i = 0; i <= nr; i++)
 		perf_mmap_unmark_page(base + (i * PAGE_SIZE));
 
 	vfree(base);
@@ -387,7 +393,7 @@ struct ring_buffer *rb_alloc(int nr_pages, long watermark, int cpu, int flags)
 	rb->user_page = all_buf;
 	rb->data_pages[0] = all_buf + PAGE_SIZE;
 	rb->page_order = ilog2(nr_pages);
-	rb->nr_pages = 1;
+	rb->nr_pages = !!nr_pages;
 
 	ring_buffer_init(rb, watermark, flags);