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, 594 insertions, 0 deletions

diff --git a/drivers/hwmon/ibmpex.c b/drivers/hwmon/ibmpex.c
new file mode 100644
index 000000000..dec730798
--- /dev/null
+++ b/drivers/hwmon/ibmpex.c
@@ -0,0 +1,594 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * A hwmon driver for the IBM PowerExecutive temperature/power sensors
+ * Copyright (C) 2007 IBM
+ *
+ * Author: Darrick J. Wong <darrick.wong@oracle.com>
+ */
+
+#include <linux/ipmi.h>
+#include <linux/module.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/jiffies.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+
+#define REFRESH_INTERVAL	(2 * HZ)
+#define DRVNAME			"ibmpex"
+
+#define PEX_GET_VERSION		1
+#define PEX_GET_SENSOR_COUNT	2
+#define PEX_GET_SENSOR_NAME	3
+#define PEX_RESET_HIGH_LOW	4
+#define PEX_GET_SENSOR_DATA	6
+
+#define PEX_NET_FUNCTION	0x3A
+#define PEX_COMMAND		0x3C
+
+static inline u16 extract_value(const char *data, int offset)
+{
+	return be16_to_cpup((__be16 *)&data[offset]);
+}
+
+#define TEMP_SENSOR		1
+#define POWER_SENSOR		2
+
+#define PEX_SENSOR_TYPE_LEN	3
+static u8 const power_sensor_sig[] = {0x70, 0x77, 0x72};
+static u8 const temp_sensor_sig[]  = {0x74, 0x65, 0x6D};
+
+#define PEX_MULT_LEN		2
+static u8 const watt_sensor_sig[]  = {0x41, 0x43};
+
+#define PEX_NUM_SENSOR_FUNCS	3
+static const char * const sensor_name_suffixes[] = {
+	"",
+	"_lowest",
+	"_highest"
+};
+
+static void ibmpex_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data);
+static void ibmpex_register_bmc(int iface, struct device *dev);
+static void ibmpex_bmc_gone(int iface);
+
+struct ibmpex_sensor_data {
+	int			in_use;
+	s16			values[PEX_NUM_SENSOR_FUNCS];
+	int			multiplier;
+
+	struct sensor_device_attribute_2	attr[PEX_NUM_SENSOR_FUNCS];
+};
+
+struct ibmpex_bmc_data {
+	struct list_head	list;
+	struct device		*hwmon_dev;
+	struct device		*bmc_device;
+	struct mutex		lock;
+	bool			valid;
+	unsigned long		last_updated;	/* In jiffies */
+
+	struct ipmi_addr	address;
+	struct completion	read_complete;
+	struct ipmi_user	*user;
+	int			interface;
+
+	struct kernel_ipmi_msg	tx_message;
+	unsigned char		tx_msg_data[IPMI_MAX_MSG_LENGTH];
+	long			tx_msgid;
+
+	unsigned char		rx_msg_data[IPMI_MAX_MSG_LENGTH];
+	unsigned long		rx_msg_len;
+	unsigned char		rx_result;
+	int			rx_recv_type;
+
+	unsigned char		sensor_major;
+	unsigned char		sensor_minor;
+
+	unsigned char		num_sensors;
+	struct ibmpex_sensor_data	*sensors;
+};
+
+struct ibmpex_driver_data {
+	struct list_head	bmc_data;
+	struct ipmi_smi_watcher	bmc_events;
+	struct ipmi_user_hndl	ipmi_hndlrs;
+};
+
+static struct ibmpex_driver_data driver_data = {
+	.bmc_data = LIST_HEAD_INIT(driver_data.bmc_data),
+	.bmc_events = {
+		.owner = THIS_MODULE,
+		.new_smi = ibmpex_register_bmc,
+		.smi_gone = ibmpex_bmc_gone,
+	},
+	.ipmi_hndlrs = {
+		.ipmi_recv_hndl = ibmpex_msg_handler,
+	},
+};
+
+static int ibmpex_send_message(struct ibmpex_bmc_data *data)
+{
+	int err;
+
+	err = ipmi_validate_addr(&data->address, sizeof(data->address));
+	if (err)
+		goto out;
+
+	data->tx_msgid++;
+	err = ipmi_request_settime(data->user, &data->address, data->tx_msgid,
+				   &data->tx_message, data, 0, 0, 0);
+	if (err)
+		goto out1;
+
+	return 0;
+out1:
+	dev_err(data->bmc_device, "request_settime=%x\n", err);
+	return err;
+out:
+	dev_err(data->bmc_device, "validate_addr=%x\n", err);
+	return err;
+}
+
+static int ibmpex_ver_check(struct ibmpex_bmc_data *data)
+{
+	data->tx_msg_data[0] = PEX_GET_VERSION;
+	data->tx_message.data_len = 1;
+	ibmpex_send_message(data);
+
+	wait_for_completion(&data->read_complete);
+
+	if (data->rx_result || data->rx_msg_len != 6)
+		return -ENOENT;
+
+	data->sensor_major = data->rx_msg_data[0];
+	data->sensor_minor = data->rx_msg_data[1];
+
+	dev_info(data->bmc_device,
+		 "Found BMC with sensor interface v%d.%d %d-%02d-%02d on interface %d\n",
+		 data->sensor_major,
+		 data->sensor_minor,
+		 extract_value(data->rx_msg_data, 2),
+		 data->rx_msg_data[4],
+		 data->rx_msg_data[5],
+		 data->interface);
+
+	return 0;
+}
+
+static int ibmpex_query_sensor_count(struct ibmpex_bmc_data *data)
+{
+	data->tx_msg_data[0] = PEX_GET_SENSOR_COUNT;
+	data->tx_message.data_len = 1;
+	ibmpex_send_message(data);
+
+	wait_for_completion(&data->read_complete);
+
+	if (data->rx_result || data->rx_msg_len != 1)
+		return -ENOENT;
+
+	return data->rx_msg_data[0];
+}
+
+static int ibmpex_query_sensor_name(struct ibmpex_bmc_data *data, int sensor)
+{
+	data->tx_msg_data[0] = PEX_GET_SENSOR_NAME;
+	data->tx_msg_data[1] = sensor;
+	data->tx_message.data_len = 2;
+	ibmpex_send_message(data);
+
+	wait_for_completion(&data->read_complete);
+
+	if (data->rx_result || data->rx_msg_len < 1)
+		return -ENOENT;
+
+	return 0;
+}
+
+static int ibmpex_query_sensor_data(struct ibmpex_bmc_data *data, int sensor)
+{
+	data->tx_msg_data[0] = PEX_GET_SENSOR_DATA;
+	data->tx_msg_data[1] = sensor;
+	data->tx_message.data_len = 2;
+	ibmpex_send_message(data);
+
+	wait_for_completion(&data->read_complete);
+
+	if (data->rx_result || data->rx_msg_len < 26) {
+		dev_err(data->bmc_device, "Error reading sensor %d.\n",
+			sensor);
+		return -ENOENT;
+	}
+
+	return 0;
+}
+
+static int ibmpex_reset_high_low_data(struct ibmpex_bmc_data *data)
+{
+	data->tx_msg_data[0] = PEX_RESET_HIGH_LOW;
+	data->tx_message.data_len = 1;
+	ibmpex_send_message(data);
+
+	wait_for_completion(&data->read_complete);
+
+	return 0;
+}
+
+static void ibmpex_update_device(struct ibmpex_bmc_data *data)
+{
+	int i, err;
+
+	mutex_lock(&data->lock);
+	if (time_before(jiffies, data->last_updated + REFRESH_INTERVAL) &&
+	    data->valid)
+		goto out;
+
+	for (i = 0; i < data->num_sensors; i++) {
+		if (!data->sensors[i].in_use)
+			continue;
+		err = ibmpex_query_sensor_data(data, i);
+		if (err)
+			continue;
+		data->sensors[i].values[0] =
+			extract_value(data->rx_msg_data, 16);
+		data->sensors[i].values[1] =
+			extract_value(data->rx_msg_data, 18);
+		data->sensors[i].values[2] =
+			extract_value(data->rx_msg_data, 20);
+	}
+
+	data->last_updated = jiffies;
+	data->valid = true;
+
+out:
+	mutex_unlock(&data->lock);
+}
+
+static struct ibmpex_bmc_data *get_bmc_data(int iface)
+{
+	struct ibmpex_bmc_data *p, *next;
+
+	list_for_each_entry_safe(p, next, &driver_data.bmc_data, list)
+		if (p->interface == iface)
+			return p;
+
+	return NULL;
+}
+
+static DEVICE_STRING_ATTR_RO(name, 0444, DRVNAME);
+
+static ssize_t ibmpex_show_sensor(struct device *dev,
+				  struct device_attribute *devattr,
+				  char *buf)
+{
+	struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(devattr);
+	struct ibmpex_bmc_data *data = dev_get_drvdata(dev);
+	int mult = data->sensors[attr->index].multiplier;
+	ibmpex_update_device(data);
+
+	return sprintf(buf, "%d\n",
+		       data->sensors[attr->index].values[attr->nr] * mult);
+}
+
+static ssize_t ibmpex_high_low_store(struct device *dev,
+				     struct device_attribute *devattr,
+				     const char *buf, size_t count)
+{
+	struct ibmpex_bmc_data *data = dev_get_drvdata(dev);
+
+	ibmpex_reset_high_low_data(data);
+
+	return count;
+}
+
+static SENSOR_DEVICE_ATTR_WO(reset_high_low, ibmpex_high_low, 0);
+
+static int is_power_sensor(const char *sensor_id, int len)
+{
+	if (len < PEX_SENSOR_TYPE_LEN)
+		return 0;
+
+	if (!memcmp(sensor_id, power_sensor_sig, PEX_SENSOR_TYPE_LEN))
+		return 1;
+	return 0;
+}
+
+static int is_temp_sensor(const char *sensor_id, int len)
+{
+	if (len < PEX_SENSOR_TYPE_LEN)
+		return 0;
+
+	if (!memcmp(sensor_id, temp_sensor_sig, PEX_SENSOR_TYPE_LEN))
+		return 1;
+	return 0;
+}
+
+static int power_sensor_multiplier(struct ibmpex_bmc_data *data,
+				   const char *sensor_id, int len)
+{
+	int i;
+
+	if (data->sensor_major == 2)
+		return 1000000;
+
+	for (i = PEX_SENSOR_TYPE_LEN; i < len - 1; i++)
+		if (!memcmp(&sensor_id[i], watt_sensor_sig, PEX_MULT_LEN))
+			return 1000000;
+
+	return 100000;
+}
+
+static int create_sensor(struct ibmpex_bmc_data *data, int type,
+			 int counter, int sensor, int func)
+{
+	int err;
+	char *n;
+
+	n = kmalloc(32, GFP_KERNEL);
+	if (!n)
+		return -ENOMEM;
+
+	if (type == TEMP_SENSOR)
+		sprintf(n, "temp%d_input%s",
+			counter, sensor_name_suffixes[func]);
+	else if (type == POWER_SENSOR)
+		sprintf(n, "power%d_average%s",
+			counter, sensor_name_suffixes[func]);
+
+	sysfs_attr_init(&data->sensors[sensor].attr[func].dev_attr.attr);
+	data->sensors[sensor].attr[func].dev_attr.attr.name = n;
+	data->sensors[sensor].attr[func].dev_attr.attr.mode = 0444;
+	data->sensors[sensor].attr[func].dev_attr.show = ibmpex_show_sensor;
+	data->sensors[sensor].attr[func].index = sensor;
+	data->sensors[sensor].attr[func].nr = func;
+
+	err = device_create_file(data->bmc_device,
+				 &data->sensors[sensor].attr[func].dev_attr);
+	if (err) {
+		data->sensors[sensor].attr[func].dev_attr.attr.name = NULL;
+		kfree(n);
+		return err;
+	}
+
+	return 0;
+}
+
+static int ibmpex_find_sensors(struct ibmpex_bmc_data *data)
+{
+	int i, j, err;
+	int sensor_type;
+	int sensor_counter;
+	int num_power = 0;
+	int num_temp = 0;
+
+	err = ibmpex_query_sensor_count(data);
+	if (err <= 0)
+		return -ENOENT;
+	data->num_sensors = err;
+
+	data->sensors = kzalloc_objs(*data->sensors, data->num_sensors);
+	if (!data->sensors)
+		return -ENOMEM;
+
+	for (i = 0; i < data->num_sensors; i++) {
+		err = ibmpex_query_sensor_name(data, i);
+		if (err)
+			continue;
+
+		if (is_power_sensor(data->rx_msg_data, data->rx_msg_len)) {
+			sensor_type = POWER_SENSOR;
+			num_power++;
+			sensor_counter = num_power;
+			data->sensors[i].multiplier =
+				power_sensor_multiplier(data,
+							data->rx_msg_data,
+							data->rx_msg_len);
+		} else if (is_temp_sensor(data->rx_msg_data,
+					  data->rx_msg_len)) {
+			sensor_type = TEMP_SENSOR;
+			num_temp++;
+			sensor_counter = num_temp;
+			data->sensors[i].multiplier = 1000;
+		} else
+			continue;
+
+		data->sensors[i].in_use = 1;
+
+		/* Create attributes */
+		for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
+			err = create_sensor(data, sensor_type, sensor_counter,
+					    i, j);
+			if (err)
+				goto exit_remove;
+		}
+	}
+
+	err = device_create_file(data->bmc_device,
+			&sensor_dev_attr_reset_high_low.dev_attr);
+	if (err)
+		goto exit_remove;
+
+	err = device_create_file(data->bmc_device, &dev_attr_name.attr);
+	if (err)
+		goto exit_remove;
+
+	return 0;
+
+exit_remove:
+	device_remove_file(data->bmc_device,
+			   &sensor_dev_attr_reset_high_low.dev_attr);
+	device_remove_file(data->bmc_device, &dev_attr_name.attr);
+	for (i = 0; i < data->num_sensors; i++)
+		for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
+			if (!data->sensors[i].attr[j].dev_attr.attr.name)
+				continue;
+			device_remove_file(data->bmc_device,
+				&data->sensors[i].attr[j].dev_attr);
+			kfree(data->sensors[i].attr[j].dev_attr.attr.name);
+		}
+
+	kfree(data->sensors);
+	return err;
+}
+
+static void ibmpex_register_bmc(int iface, struct device *dev)
+{
+	struct ibmpex_bmc_data *data;
+	int err;
+
+	data = kzalloc_obj(*data);
+	if (!data)
+		return;
+
+	data->address.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
+	data->address.channel = IPMI_BMC_CHANNEL;
+	data->address.data[0] = 0;
+	data->interface = iface;
+	data->bmc_device = dev;
+
+	/* Create IPMI messaging interface user */
+	err = ipmi_create_user(data->interface, &driver_data.ipmi_hndlrs,
+			       data, &data->user);
+	if (err < 0) {
+		dev_err(dev,
+			"Unable to register user with IPMI interface %d\n",
+			data->interface);
+		goto out;
+	}
+
+	mutex_init(&data->lock);
+
+	/* Initialize message */
+	data->tx_msgid = 0;
+	init_completion(&data->read_complete);
+	data->tx_message.netfn = PEX_NET_FUNCTION;
+	data->tx_message.cmd = PEX_COMMAND;
+	data->tx_message.data = data->tx_msg_data;
+
+	/* Does this BMC support PowerExecutive? */
+	err = ibmpex_ver_check(data);
+	if (err)
+		goto out_user;
+
+	/* Register the BMC as a HWMON class device */
+	data->hwmon_dev = hwmon_device_register(data->bmc_device);
+
+	if (IS_ERR(data->hwmon_dev)) {
+		dev_err(data->bmc_device,
+			"Unable to register hwmon device for IPMI interface %d\n",
+			data->interface);
+		goto out_user;
+	}
+
+	/* finally add the new bmc data to the bmc data list */
+	dev_set_drvdata(dev, data);
+	list_add_tail(&data->list, &driver_data.bmc_data);
+
+	/* Now go find all the sensors */
+	err = ibmpex_find_sensors(data);
+	if (err) {
+		dev_err(data->bmc_device, "Error %d finding sensors\n", err);
+		goto out_register;
+	}
+
+	return;
+
+out_register:
+	list_del(&data->list);
+	hwmon_device_unregister(data->hwmon_dev);
+out_user:
+	ipmi_destroy_user(data->user);
+out:
+	kfree(data);
+}
+
+static void ibmpex_bmc_delete(struct ibmpex_bmc_data *data)
+{
+	int i, j;
+
+	device_remove_file(data->bmc_device,
+			   &sensor_dev_attr_reset_high_low.dev_attr);
+	device_remove_file(data->bmc_device, &dev_attr_name.attr);
+	for (i = 0; i < data->num_sensors; i++)
+		for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
+			if (!data->sensors[i].attr[j].dev_attr.attr.name)
+				continue;
+			device_remove_file(data->bmc_device,
+				&data->sensors[i].attr[j].dev_attr);
+			kfree(data->sensors[i].attr[j].dev_attr.attr.name);
+		}
+
+	list_del(&data->list);
+	dev_set_drvdata(data->bmc_device, NULL);
+	hwmon_device_unregister(data->hwmon_dev);
+	ipmi_destroy_user(data->user);
+	kfree(data->sensors);
+	kfree(data);
+}
+
+static void ibmpex_bmc_gone(int iface)
+{
+	struct ibmpex_bmc_data *data = get_bmc_data(iface);
+
+	if (!data)
+		return;
+
+	ibmpex_bmc_delete(data);
+}
+
+static void ibmpex_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data)
+{
+	struct ibmpex_bmc_data *data = user_msg_data;
+
+	if (msg->msgid != data->tx_msgid) {
+		dev_err(data->bmc_device,
+			"Mismatch between received msgid (%02x) and transmitted msgid (%02x)!\n",
+			(int)msg->msgid,
+			(int)data->tx_msgid);
+		ipmi_free_recv_msg(msg);
+		return;
+	}
+
+	data->rx_recv_type = msg->recv_type;
+	if (msg->msg.data_len > 0)
+		data->rx_result = msg->msg.data[0];
+	else
+		data->rx_result = IPMI_UNKNOWN_ERR_COMPLETION_CODE;
+
+	if (msg->msg.data_len > 1) {
+		data->rx_msg_len = msg->msg.data_len - 1;
+		memcpy(data->rx_msg_data, msg->msg.data + 1, data->rx_msg_len);
+	} else
+		data->rx_msg_len = 0;
+
+	ipmi_free_recv_msg(msg);
+	complete(&data->read_complete);
+}
+
+static int __init ibmpex_init(void)
+{
+	return ipmi_smi_watcher_register(&driver_data.bmc_events);
+}
+
+static void __exit ibmpex_exit(void)
+{
+	struct ibmpex_bmc_data *p, *next;
+
+	ipmi_smi_watcher_unregister(&driver_data.bmc_events);
+	list_for_each_entry_safe(p, next, &driver_data.bmc_data, list)
+		ibmpex_bmc_delete(p);
+}
+
+MODULE_AUTHOR("Darrick J. Wong <darrick.wong@oracle.com>");
+MODULE_DESCRIPTION("IBM PowerExecutive power/temperature sensor driver");
+MODULE_LICENSE("GPL");
+
+module_init(ibmpex_init);
+module_exit(ibmpex_exit);
+
+MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3350-*");
+MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3550-*");
+MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3650-*");
+MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3655-*");
+MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3755-*");