Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 562 insertions, 0 deletions

diff --git a/drivers/dma/idxd/perfmon.c b/drivers/dma/idxd/perfmon.c
new file mode 100644
index 000000000..f854bd31a
--- /dev/null
+++ b/drivers/dma/idxd/perfmon.c
@@ -0,0 +1,562 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright(c) 2020 Intel Corporation. All rights rsvd. */
+
+#include <linux/sched/task.h>
+#include <linux/io-64-nonatomic-lo-hi.h>
+#include "idxd.h"
+#include "perfmon.h"
+
+/*
+ * These attributes specify the bits in the config word that the perf
+ * syscall uses to pass the event ids and categories to perfmon.
+ */
+DEFINE_PERFMON_FORMAT_ATTR(event_category, "config:0-3");
+DEFINE_PERFMON_FORMAT_ATTR(event, "config:4-31");
+
+/*
+ * These attributes specify the bits in the config1 word that the perf
+ * syscall uses to pass filter data to perfmon.
+ */
+DEFINE_PERFMON_FORMAT_ATTR(filter_wq, "config1:0-31");
+DEFINE_PERFMON_FORMAT_ATTR(filter_tc, "config1:32-39");
+DEFINE_PERFMON_FORMAT_ATTR(filter_pgsz, "config1:40-43");
+DEFINE_PERFMON_FORMAT_ATTR(filter_sz, "config1:44-51");
+DEFINE_PERFMON_FORMAT_ATTR(filter_eng, "config1:52-59");
+
+#define PERFMON_FILTERS_START	2
+#define PERFMON_FILTERS_MAX	5
+
+static struct attribute *perfmon_format_attrs[] = {
+	&format_attr_idxd_event_category.attr,
+	&format_attr_idxd_event.attr,
+	&format_attr_idxd_filter_wq.attr,
+	&format_attr_idxd_filter_tc.attr,
+	&format_attr_idxd_filter_pgsz.attr,
+	&format_attr_idxd_filter_sz.attr,
+	&format_attr_idxd_filter_eng.attr,
+	NULL,
+};
+
+static struct attribute_group perfmon_format_attr_group = {
+	.name = "format",
+	.attrs = perfmon_format_attrs,
+};
+
+static const struct attribute_group *perfmon_attr_groups[] = {
+	&perfmon_format_attr_group,
+	NULL,
+};
+
+static bool is_idxd_event(struct idxd_pmu *idxd_pmu, struct perf_event *event)
+{
+	return &idxd_pmu->pmu == event->pmu;
+}
+
+static int perfmon_collect_events(struct idxd_pmu *idxd_pmu,
+				  struct perf_event *leader,
+				  bool do_grp)
+{
+	struct perf_event *event;
+	int n, max_count;
+
+	max_count = idxd_pmu->n_counters;
+	n = idxd_pmu->n_events;
+
+	if (n >= max_count)
+		return -EINVAL;
+
+	if (is_idxd_event(idxd_pmu, leader)) {
+		idxd_pmu->event_list[n] = leader;
+		idxd_pmu->event_list[n]->hw.idx = n;
+		n++;
+	}
+
+	if (!do_grp)
+		return n;
+
+	for_each_sibling_event(event, leader) {
+		if (!is_idxd_event(idxd_pmu, event) ||
+		    event->state <= PERF_EVENT_STATE_OFF)
+			continue;
+
+		if (n >= max_count)
+			return -EINVAL;
+
+		idxd_pmu->event_list[n] = event;
+		idxd_pmu->event_list[n]->hw.idx = n;
+		n++;
+	}
+
+	return n;
+}
+
+static void perfmon_assign_hw_event(struct idxd_pmu *idxd_pmu,
+				    struct perf_event *event, int idx)
+{
+	struct idxd_device *idxd = idxd_pmu->idxd;
+	struct hw_perf_event *hwc = &event->hw;
+
+	hwc->idx = idx;
+	hwc->config_base = ioread64(CNTRCFG_REG(idxd, idx));
+	hwc->event_base = ioread64(CNTRCFG_REG(idxd, idx));
+}
+
+static int perfmon_assign_event(struct idxd_pmu *idxd_pmu,
+				struct perf_event *event)
+{
+	int i;
+
+	for (i = 0; i < IDXD_PMU_EVENT_MAX; i++)
+		if (!test_and_set_bit(i, idxd_pmu->used_mask))
+			return i;
+
+	return -EINVAL;
+}
+
+/*
+ * Check whether there are enough counters to satisfy that all the
+ * events in the group can actually be scheduled at the same time.
+ *
+ * To do this, create a fake idxd_pmu object so the event collection
+ * and assignment functions can be used without affecting the internal
+ * state of the real idxd_pmu object.
+ */
+static int perfmon_validate_group(struct idxd_pmu *pmu,
+				  struct perf_event *event)
+{
+	struct perf_event *leader = event->group_leader;
+	struct idxd_pmu *fake_pmu;
+	int i, ret = 0, n, idx;
+
+	fake_pmu = kzalloc_obj(*fake_pmu);
+	if (!fake_pmu)
+		return -ENOMEM;
+
+	fake_pmu->pmu.name = pmu->pmu.name;
+	fake_pmu->n_counters = pmu->n_counters;
+
+	n = perfmon_collect_events(fake_pmu, leader, true);
+	if (n < 0) {
+		ret = n;
+		goto out;
+	}
+
+	fake_pmu->n_events = n;
+	n = perfmon_collect_events(fake_pmu, event, false);
+	if (n < 0) {
+		ret = n;
+		goto out;
+	}
+
+	fake_pmu->n_events = n;
+
+	for (i = 0; i < n; i++) {
+		event = fake_pmu->event_list[i];
+
+		idx = perfmon_assign_event(fake_pmu, event);
+		if (idx < 0) {
+			ret = idx;
+			goto out;
+		}
+	}
+out:
+	kfree(fake_pmu);
+
+	return ret;
+}
+
+static int perfmon_pmu_event_init(struct perf_event *event)
+{
+	struct idxd_device *idxd;
+	int ret = 0;
+
+	idxd = event_to_idxd(event);
+	event->hw.idx = -1;
+
+	if (event->attr.type != event->pmu->type)
+		return -ENOENT;
+
+	/* sampling not supported */
+	if (event->attr.sample_period)
+		return -EINVAL;
+
+	if (event->cpu < 0)
+		return -EINVAL;
+
+	if (event->pmu != &idxd->idxd_pmu->pmu)
+		return -EINVAL;
+
+	event->hw.event_base = ioread64(PERFMON_TABLE_OFFSET(idxd));
+	event->hw.config = event->attr.config;
+
+	if (event->group_leader != event)
+		 /* non-group events have themselves as leader */
+		ret = perfmon_validate_group(idxd->idxd_pmu, event);
+
+	return ret;
+}
+
+static inline u64 perfmon_pmu_read_counter(struct perf_event *event)
+{
+	struct hw_perf_event *hwc = &event->hw;
+	struct idxd_device *idxd;
+	int cntr = hwc->idx;
+
+	idxd = event_to_idxd(event);
+
+	return ioread64(CNTRDATA_REG(idxd, cntr));
+}
+
+static void perfmon_pmu_event_update(struct perf_event *event)
+{
+	struct idxd_device *idxd = event_to_idxd(event);
+	u64 prev_raw_count, new_raw_count, delta, p, n;
+	int shift = 64 - idxd->idxd_pmu->counter_width;
+	struct hw_perf_event *hwc = &event->hw;
+
+	prev_raw_count = local64_read(&hwc->prev_count);
+	do {
+		new_raw_count = perfmon_pmu_read_counter(event);
+	} while (!local64_try_cmpxchg(&hwc->prev_count,
+				      &prev_raw_count, new_raw_count));
+	n = (new_raw_count << shift);
+	p = (prev_raw_count << shift);
+
+	delta = ((n - p) >> shift);
+
+	local64_add(delta, &event->count);
+}
+
+void perfmon_counter_overflow(struct idxd_device *idxd)
+{
+	int i, n_counters, max_loop = OVERFLOW_SIZE;
+	struct perf_event *event;
+	unsigned long ovfstatus;
+
+	n_counters = min(idxd->idxd_pmu->n_counters, OVERFLOW_SIZE);
+
+	ovfstatus = ioread32(OVFSTATUS_REG(idxd));
+
+	/*
+	 * While updating overflowed counters, other counters behind
+	 * them could overflow and be missed in a given pass.
+	 * Normally this could happen at most n_counters times, but in
+	 * theory a tiny counter width could result in continual
+	 * overflows and endless looping.  max_loop provides a
+	 * failsafe in that highly unlikely case.
+	 */
+	while (ovfstatus && max_loop--) {
+		/* Figure out which counter(s) overflowed */
+		for_each_set_bit(i, &ovfstatus, n_counters) {
+			unsigned long ovfstatus_clear = 0;
+
+			/* Update event->count for overflowed counter */
+			event = idxd->idxd_pmu->event_list[i];
+			perfmon_pmu_event_update(event);
+			/* Writing 1 to OVFSTATUS bit clears it */
+			set_bit(i, &ovfstatus_clear);
+			iowrite32(ovfstatus_clear, OVFSTATUS_REG(idxd));
+		}
+
+		ovfstatus = ioread32(OVFSTATUS_REG(idxd));
+	}
+
+	/*
+	 * Should never happen.  If so, it means a counter(s) looped
+	 * around twice while this handler was running.
+	 */
+	WARN_ON_ONCE(ovfstatus);
+}
+
+static inline void perfmon_reset_config(struct idxd_device *idxd)
+{
+	iowrite32(CONFIG_RESET, PERFRST_REG(idxd));
+	iowrite32(0, OVFSTATUS_REG(idxd));
+	iowrite32(0, PERFFRZ_REG(idxd));
+}
+
+static inline void perfmon_reset_counters(struct idxd_device *idxd)
+{
+	iowrite32(CNTR_RESET, PERFRST_REG(idxd));
+}
+
+static inline void perfmon_reset(struct idxd_device *idxd)
+{
+	perfmon_reset_config(idxd);
+	perfmon_reset_counters(idxd);
+}
+
+static void perfmon_pmu_event_start(struct perf_event *event, int mode)
+{
+	u32 flt_wq, flt_tc, flt_pg_sz, flt_xfer_sz, flt_eng = 0;
+	u64 cntr_cfg, cntrdata, event_enc, event_cat = 0;
+	struct hw_perf_event *hwc = &event->hw;
+	union filter_cfg flt_cfg;
+	union event_cfg event_cfg;
+	struct idxd_device *idxd;
+	int cntr;
+
+	idxd = event_to_idxd(event);
+
+	event->hw.idx = hwc->idx;
+	cntr = hwc->idx;
+
+	/* Obtain event category and event value from user space */
+	event_cfg.val = event->attr.config;
+	flt_cfg.val = event->attr.config1;
+	event_cat = event_cfg.event_cat;
+	event_enc = event_cfg.event_enc;
+
+	/* Obtain filter configuration from user space */
+	flt_wq = flt_cfg.wq;
+	flt_tc = flt_cfg.tc;
+	flt_pg_sz = flt_cfg.pg_sz;
+	flt_xfer_sz = flt_cfg.xfer_sz;
+	flt_eng = flt_cfg.eng;
+
+	if (flt_wq && test_bit(FLT_WQ, &idxd->idxd_pmu->supported_filters))
+		iowrite32(flt_wq, FLTCFG_REG(idxd, cntr, FLT_WQ));
+	if (flt_tc && test_bit(FLT_TC, &idxd->idxd_pmu->supported_filters))
+		iowrite32(flt_tc, FLTCFG_REG(idxd, cntr, FLT_TC));
+	if (flt_pg_sz && test_bit(FLT_PG_SZ, &idxd->idxd_pmu->supported_filters))
+		iowrite32(flt_pg_sz, FLTCFG_REG(idxd, cntr, FLT_PG_SZ));
+	if (flt_xfer_sz && test_bit(FLT_XFER_SZ, &idxd->idxd_pmu->supported_filters))
+		iowrite32(flt_xfer_sz, FLTCFG_REG(idxd, cntr, FLT_XFER_SZ));
+	if (flt_eng && test_bit(FLT_ENG, &idxd->idxd_pmu->supported_filters))
+		iowrite32(flt_eng, FLTCFG_REG(idxd, cntr, FLT_ENG));
+
+	/* Read the start value */
+	cntrdata = ioread64(CNTRDATA_REG(idxd, cntr));
+	local64_set(&event->hw.prev_count, cntrdata);
+
+	/* Set counter to event/category */
+	cntr_cfg = event_cat << CNTRCFG_CATEGORY_SHIFT;
+	cntr_cfg |= event_enc << CNTRCFG_EVENT_SHIFT;
+	/* Set interrupt on overflow and counter enable bits */
+	cntr_cfg |= (CNTRCFG_IRQ_OVERFLOW | CNTRCFG_ENABLE);
+
+	iowrite64(cntr_cfg, CNTRCFG_REG(idxd, cntr));
+}
+
+static void perfmon_pmu_event_stop(struct perf_event *event, int mode)
+{
+	struct hw_perf_event *hwc = &event->hw;
+	struct idxd_device *idxd;
+	int i, cntr = hwc->idx;
+	u64 cntr_cfg;
+
+	idxd = event_to_idxd(event);
+
+	/* remove this event from event list */
+	for (i = 0; i < idxd->idxd_pmu->n_events; i++) {
+		if (event != idxd->idxd_pmu->event_list[i])
+			continue;
+
+		for (++i; i < idxd->idxd_pmu->n_events; i++)
+			idxd->idxd_pmu->event_list[i - 1] = idxd->idxd_pmu->event_list[i];
+		--idxd->idxd_pmu->n_events;
+		break;
+	}
+
+	cntr_cfg = ioread64(CNTRCFG_REG(idxd, cntr));
+	cntr_cfg &= ~CNTRCFG_ENABLE;
+	iowrite64(cntr_cfg, CNTRCFG_REG(idxd, cntr));
+
+	if (mode == PERF_EF_UPDATE)
+		perfmon_pmu_event_update(event);
+
+	event->hw.idx = -1;
+	clear_bit(cntr, idxd->idxd_pmu->used_mask);
+}
+
+static void perfmon_pmu_event_del(struct perf_event *event, int mode)
+{
+	perfmon_pmu_event_stop(event, PERF_EF_UPDATE);
+}
+
+static int perfmon_pmu_event_add(struct perf_event *event, int flags)
+{
+	struct idxd_device *idxd = event_to_idxd(event);
+	struct idxd_pmu *idxd_pmu = idxd->idxd_pmu;
+	struct hw_perf_event *hwc = &event->hw;
+	int idx, n;
+
+	n = perfmon_collect_events(idxd_pmu, event, false);
+	if (n < 0)
+		return n;
+
+	hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
+	if (!(flags & PERF_EF_START))
+		hwc->state |= PERF_HES_ARCH;
+
+	idx = perfmon_assign_event(idxd_pmu, event);
+	if (idx < 0)
+		return idx;
+
+	perfmon_assign_hw_event(idxd_pmu, event, idx);
+
+	if (flags & PERF_EF_START)
+		perfmon_pmu_event_start(event, 0);
+
+	idxd_pmu->n_events = n;
+
+	return 0;
+}
+
+static void enable_perfmon_pmu(struct idxd_device *idxd)
+{
+	iowrite32(COUNTER_UNFREEZE, PERFFRZ_REG(idxd));
+}
+
+static void disable_perfmon_pmu(struct idxd_device *idxd)
+{
+	iowrite32(COUNTER_FREEZE, PERFFRZ_REG(idxd));
+}
+
+static void perfmon_pmu_enable(struct pmu *pmu)
+{
+	struct idxd_device *idxd = pmu_to_idxd(pmu);
+
+	enable_perfmon_pmu(idxd);
+}
+
+static void perfmon_pmu_disable(struct pmu *pmu)
+{
+	struct idxd_device *idxd = pmu_to_idxd(pmu);
+
+	disable_perfmon_pmu(idxd);
+}
+
+static void skip_filter(int i)
+{
+	int j;
+
+	for (j = i; j < PERFMON_FILTERS_MAX; j++)
+		perfmon_format_attrs[PERFMON_FILTERS_START + j] =
+			perfmon_format_attrs[PERFMON_FILTERS_START + j + 1];
+}
+
+static void idxd_pmu_init(struct idxd_pmu *idxd_pmu)
+{
+	int i;
+
+	for (i = 0 ; i < PERFMON_FILTERS_MAX; i++) {
+		if (!test_bit(i, &idxd_pmu->supported_filters))
+			skip_filter(i);
+	}
+
+	idxd_pmu->pmu.name		= idxd_pmu->name;
+	idxd_pmu->pmu.attr_groups	= perfmon_attr_groups;
+	idxd_pmu->pmu.task_ctx_nr	= perf_invalid_context;
+	idxd_pmu->pmu.event_init	= perfmon_pmu_event_init;
+	idxd_pmu->pmu.pmu_enable	= perfmon_pmu_enable;
+	idxd_pmu->pmu.pmu_disable	= perfmon_pmu_disable;
+	idxd_pmu->pmu.add		= perfmon_pmu_event_add;
+	idxd_pmu->pmu.del		= perfmon_pmu_event_del;
+	idxd_pmu->pmu.start		= perfmon_pmu_event_start;
+	idxd_pmu->pmu.stop		= perfmon_pmu_event_stop;
+	idxd_pmu->pmu.read		= perfmon_pmu_event_update;
+	idxd_pmu->pmu.capabilities	= PERF_PMU_CAP_NO_EXCLUDE;
+	idxd_pmu->pmu.scope		= PERF_PMU_SCOPE_SYS_WIDE;
+	idxd_pmu->pmu.module		= THIS_MODULE;
+}
+
+void perfmon_pmu_remove(struct idxd_device *idxd)
+{
+	if (!idxd->idxd_pmu)
+		return;
+
+	perf_pmu_unregister(&idxd->idxd_pmu->pmu);
+	kfree(idxd->idxd_pmu);
+	idxd->idxd_pmu = NULL;
+}
+
+int perfmon_pmu_init(struct idxd_device *idxd)
+{
+	union idxd_perfcap perfcap;
+	struct idxd_pmu *idxd_pmu;
+	int rc = -ENODEV;
+
+	/*
+	 * If perfmon_offset or num_counters is 0, it means perfmon is
+	 * not supported on this hardware.
+	 */
+	if (idxd->perfmon_offset == 0)
+		return -ENODEV;
+
+	idxd_pmu = kzalloc_obj(*idxd_pmu);
+	if (!idxd_pmu)
+		return -ENOMEM;
+
+	idxd_pmu->idxd = idxd;
+	idxd->idxd_pmu = idxd_pmu;
+
+	if (idxd->data->type == IDXD_TYPE_DSA) {
+		rc = sprintf(idxd_pmu->name, "dsa%d", idxd->id);
+		if (rc < 0)
+			goto free;
+	} else if (idxd->data->type == IDXD_TYPE_IAX) {
+		rc = sprintf(idxd_pmu->name, "iax%d", idxd->id);
+		if (rc < 0)
+			goto free;
+	} else {
+		goto free;
+	}
+
+	perfmon_reset(idxd);
+
+	perfcap.bits = ioread64(PERFCAP_REG(idxd));
+
+	/*
+	 * If total perf counter is 0, stop further registration.
+	 * This is necessary in order to support driver running on
+	 * guest which does not have pmon support.
+	 */
+	if (perfcap.num_perf_counter == 0)
+		goto free;
+
+	/* A counter width of 0 means it can't count */
+	if (perfcap.counter_width == 0)
+		goto free;
+
+	/* Overflow interrupt and counter freeze support must be available */
+	if (!perfcap.overflow_interrupt || !perfcap.counter_freeze)
+		goto free;
+
+	/* Number of event categories cannot be 0 */
+	if (perfcap.num_event_category == 0)
+		goto free;
+
+	/*
+	 * We don't support per-counter capabilities for now.
+	 */
+	if (perfcap.cap_per_counter)
+		goto free;
+
+	idxd_pmu->n_event_categories = perfcap.num_event_category;
+	idxd_pmu->supported_event_categories = perfcap.global_event_category;
+	idxd_pmu->per_counter_caps_supported = perfcap.cap_per_counter;
+
+	/* check filter capability.  If 0, then filters are not supported */
+	idxd_pmu->supported_filters = perfcap.filter;
+	if (perfcap.filter)
+		idxd_pmu->n_filters = hweight8(perfcap.filter);
+
+	/* Store the total number of counters categories, and counter width */
+	idxd_pmu->n_counters = perfcap.num_perf_counter;
+	idxd_pmu->counter_width = perfcap.counter_width;
+
+	idxd_pmu_init(idxd_pmu);
+
+	rc = perf_pmu_register(&idxd_pmu->pmu, idxd_pmu->name, -1);
+	if (rc)
+		goto free;
+
+out:
+	return rc;
+free:
+	kfree(idxd_pmu);
+	idxd->idxd_pmu = NULL;
+
+	goto out;
+}