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, 537 insertions, 0 deletions

diff --git a/drivers/hwmon/max31790.c b/drivers/hwmon/max31790.c
new file mode 100644
index 000000000..db8a0f6f1
--- /dev/null
+++ b/drivers/hwmon/max31790.c
@@ -0,0 +1,537 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * max31790.c - Part of lm_sensors, Linux kernel modules for hardware
+ *             monitoring.
+ *
+ * (C) 2015 by Il Han <corone.il.han@gmail.com>
+ */
+
+#include <linux/err.h>
+#include <linux/hwmon.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/jiffies.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+/* MAX31790 registers */
+#define MAX31790_REG_GLOBAL_CONFIG	0x00
+#define MAX31790_REG_FAN_CONFIG(ch)	(0x02 + (ch))
+#define MAX31790_REG_FAN_DYNAMICS(ch)	(0x08 + (ch))
+#define MAX31790_REG_FAN_FAULT_STATUS2	0x10
+#define MAX31790_REG_FAN_FAULT_STATUS1	0x11
+#define MAX31790_REG_TACH_COUNT(ch)	(0x18 + (ch) * 2)
+#define MAX31790_REG_PWM_DUTY_CYCLE(ch)	(0x30 + (ch) * 2)
+#define MAX31790_REG_PWMOUT(ch)		(0x40 + (ch) * 2)
+#define MAX31790_REG_TARGET_COUNT(ch)	(0x50 + (ch) * 2)
+
+/* Fan Config register bits */
+#define MAX31790_FAN_CFG_RPM_MODE	0x80
+#define MAX31790_FAN_CFG_CTRL_MON	0x10
+#define MAX31790_FAN_CFG_TACH_INPUT_EN	0x08
+#define MAX31790_FAN_CFG_TACH_INPUT	0x01
+
+/* Fan Dynamics register bits */
+#define MAX31790_FAN_DYN_SR_SHIFT	5
+#define MAX31790_FAN_DYN_SR_MASK	0xE0
+#define SR_FROM_REG(reg)		(((reg) & MAX31790_FAN_DYN_SR_MASK) \
+					 >> MAX31790_FAN_DYN_SR_SHIFT)
+
+#define FAN_RPM_MIN			120
+#define FAN_RPM_MAX			7864320
+
+#define FAN_COUNT_REG_MAX		0xffe0
+
+#define RPM_FROM_REG(reg, sr)		(((reg) >> 4) ? \
+					 ((60 * (sr) * 8192) / ((reg) >> 4)) : \
+					 FAN_RPM_MAX)
+#define RPM_TO_REG(rpm, sr)		((60 * (sr) * 8192) / ((rpm) * 2))
+
+#define NR_CHANNEL			6
+
+#define PWM_INPUT_SCALE	255
+#define MAX31790_REG_PWMOUT_SCALE	511
+
+/*
+ * Client data (each client gets its own)
+ */
+struct max31790_data {
+	struct i2c_client *client;
+	bool valid; /* zero until following fields are valid */
+	unsigned long last_updated; /* in jiffies */
+
+	/* register values */
+	u8 fan_config[NR_CHANNEL];
+	u8 fan_dynamics[NR_CHANNEL];
+	u16 fault_status;
+	u16 tach[NR_CHANNEL * 2];
+	u16 pwm[NR_CHANNEL];
+	u16 target_count[NR_CHANNEL];
+};
+
+static struct max31790_data *max31790_update_device(struct device *dev)
+{
+	struct max31790_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	int i, rv;
+
+	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
+		data->valid = false;
+		rv = i2c_smbus_read_byte_data(client,
+				MAX31790_REG_FAN_FAULT_STATUS1);
+		if (rv < 0)
+			return ERR_PTR(rv);
+		data->fault_status |= rv & 0x3F;
+
+		rv = i2c_smbus_read_byte_data(client,
+				MAX31790_REG_FAN_FAULT_STATUS2);
+		if (rv < 0)
+			return ERR_PTR(rv);
+		data->fault_status |= (rv & 0x3F) << 6;
+
+		for (i = 0; i < NR_CHANNEL; i++) {
+			rv = i2c_smbus_read_word_swapped(client,
+					MAX31790_REG_TACH_COUNT(i));
+			if (rv < 0)
+				return ERR_PTR(rv);
+			data->tach[i] = rv;
+
+			if (data->fan_config[i]
+			    & MAX31790_FAN_CFG_TACH_INPUT) {
+				rv = i2c_smbus_read_word_swapped(client,
+					MAX31790_REG_TACH_COUNT(NR_CHANNEL
+								+ i));
+				if (rv < 0)
+					return ERR_PTR(rv);
+				data->tach[NR_CHANNEL + i] = rv;
+			} else {
+				rv = i2c_smbus_read_word_swapped(client,
+						MAX31790_REG_PWM_DUTY_CYCLE(i));
+				if (rv < 0)
+					return ERR_PTR(rv);
+				data->pwm[i] = rv;
+
+				rv = i2c_smbus_read_word_swapped(client,
+						MAX31790_REG_TARGET_COUNT(i));
+				if (rv < 0)
+					return ERR_PTR(rv);
+				data->target_count[i] = rv;
+			}
+		}
+
+		data->last_updated = jiffies;
+		data->valid = true;
+	}
+	return data;
+}
+
+static const u8 tach_period[8] = { 1, 2, 4, 8, 16, 32, 32, 32 };
+
+static u8 get_tach_period(u8 fan_dynamics)
+{
+	return tach_period[SR_FROM_REG(fan_dynamics)];
+}
+
+static u8 bits_for_tach_period(int rpm)
+{
+	u8 bits;
+
+	if (rpm < 500)
+		bits = 0x0;
+	else if (rpm < 1000)
+		bits = 0x1;
+	else if (rpm < 2000)
+		bits = 0x2;
+	else if (rpm < 4000)
+		bits = 0x3;
+	else if (rpm < 8000)
+		bits = 0x4;
+	else
+		bits = 0x5;
+
+	return bits;
+}
+
+static int max31790_read_fan(struct device *dev, u32 attr, int channel,
+			     long *val)
+{
+	struct max31790_data *data = max31790_update_device(dev);
+	int sr, rpm;
+
+	if (IS_ERR(data))
+		return PTR_ERR(data);
+
+	switch (attr) {
+	case hwmon_fan_input:
+		sr = get_tach_period(data->fan_dynamics[channel % NR_CHANNEL]);
+		if (data->tach[channel] == FAN_COUNT_REG_MAX)
+			rpm = 0;
+		else
+			rpm = RPM_FROM_REG(data->tach[channel], sr);
+		*val = rpm;
+		return 0;
+	case hwmon_fan_target:
+		sr = get_tach_period(data->fan_dynamics[channel]);
+		rpm = RPM_FROM_REG(data->target_count[channel], sr);
+		*val = rpm;
+		return 0;
+	case hwmon_fan_fault:
+		*val = !!(data->fault_status & (1 << channel));
+		data->fault_status &= ~(1 << channel);
+		/*
+		 * If a fault bit is set, we need to write into one of the fan
+		 * configuration registers to clear it. Note that this also
+		 * clears the fault for the companion channel if enabled.
+		 */
+		if (*val) {
+			int reg = MAX31790_REG_TARGET_COUNT(channel % NR_CHANNEL);
+
+			return i2c_smbus_write_byte_data(data->client, reg,
+						data->target_count[channel % NR_CHANNEL] >> 8);
+		}
+		return 0;
+	case hwmon_fan_enable:
+		*val = !!(data->fan_config[channel] & MAX31790_FAN_CFG_TACH_INPUT_EN);
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int max31790_write_fan(struct device *dev, u32 attr, int channel,
+			      long val)
+{
+	struct max31790_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	int target_count;
+	int err = 0;
+	u8 bits, fan_config;
+	int sr;
+
+	switch (attr) {
+	case hwmon_fan_target:
+		val = clamp_val(val, FAN_RPM_MIN, FAN_RPM_MAX);
+		bits = bits_for_tach_period(val);
+		data->fan_dynamics[channel] =
+			((data->fan_dynamics[channel] &
+			  ~MAX31790_FAN_DYN_SR_MASK) |
+			 (bits << MAX31790_FAN_DYN_SR_SHIFT));
+		err = i2c_smbus_write_byte_data(client,
+					MAX31790_REG_FAN_DYNAMICS(channel),
+					data->fan_dynamics[channel]);
+		if (err < 0)
+			break;
+
+		sr = get_tach_period(data->fan_dynamics[channel]);
+		target_count = RPM_TO_REG(val, sr);
+		target_count = clamp_val(target_count, 0x1, 0x7FF);
+
+		data->target_count[channel] = target_count << 5;
+
+		err = i2c_smbus_write_word_swapped(client,
+					MAX31790_REG_TARGET_COUNT(channel),
+					data->target_count[channel]);
+		break;
+	case hwmon_fan_enable:
+		fan_config = data->fan_config[channel];
+		if (val == 0) {
+			fan_config &= ~MAX31790_FAN_CFG_TACH_INPUT_EN;
+		} else if (val == 1) {
+			fan_config |= MAX31790_FAN_CFG_TACH_INPUT_EN;
+		} else {
+			err = -EINVAL;
+			break;
+		}
+		if (fan_config != data->fan_config[channel]) {
+			err = i2c_smbus_write_byte_data(client, MAX31790_REG_FAN_CONFIG(channel),
+							fan_config);
+			if (!err)
+				data->fan_config[channel] = fan_config;
+		}
+		break;
+	default:
+		err = -EOPNOTSUPP;
+		break;
+	}
+	return err;
+}
+
+static umode_t max31790_fan_is_visible(const void *_data, u32 attr, int channel)
+{
+	const struct max31790_data *data = _data;
+	u8 fan_config = data->fan_config[channel % NR_CHANNEL];
+
+	switch (attr) {
+	case hwmon_fan_input:
+	case hwmon_fan_fault:
+		if (channel < NR_CHANNEL ||
+		    (fan_config & MAX31790_FAN_CFG_TACH_INPUT))
+			return 0444;
+		return 0;
+	case hwmon_fan_target:
+		if (channel < NR_CHANNEL &&
+		    !(fan_config & MAX31790_FAN_CFG_TACH_INPUT))
+			return 0644;
+		return 0;
+	case hwmon_fan_enable:
+		if (channel < NR_CHANNEL)
+			return 0644;
+		return 0;
+	default:
+		return 0;
+	}
+}
+
+static int max31790_read_pwm(struct device *dev, u32 attr, int channel,
+			     long *val)
+{
+	struct max31790_data *data = max31790_update_device(dev);
+	u8 fan_config;
+
+	if (IS_ERR(data))
+		return PTR_ERR(data);
+
+	fan_config = data->fan_config[channel];
+
+	switch (attr) {
+	case hwmon_pwm_input:
+		*val = data->pwm[channel] >> 8;
+		return 0;
+	case hwmon_pwm_enable:
+		if (fan_config & MAX31790_FAN_CFG_CTRL_MON)
+			*val = 0;
+		else if (fan_config & MAX31790_FAN_CFG_RPM_MODE)
+			*val = 2;
+		else
+			*val = 1;
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int max31790_write_pwm(struct device *dev, u32 attr, int channel,
+			      long val)
+{
+	struct max31790_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
+	u8 fan_config;
+	int err = 0;
+
+	switch (attr) {
+	case hwmon_pwm_input:
+		if (val < 0 || val > 255) {
+			err = -EINVAL;
+			break;
+		}
+
+		val = DIV_ROUND_CLOSEST(val * MAX31790_REG_PWMOUT_SCALE,
+					PWM_INPUT_SCALE);
+		data->valid = false;
+		err = i2c_smbus_write_word_swapped(client,
+						   MAX31790_REG_PWMOUT(channel),
+						   val << 7);
+		break;
+	case hwmon_pwm_enable:
+		fan_config = data->fan_config[channel];
+		if (val == 0) {
+			fan_config |= MAX31790_FAN_CFG_CTRL_MON;
+			/*
+			 * Disable RPM mode; otherwise disabling fan speed
+			 * monitoring is not possible.
+			 */
+			fan_config &= ~MAX31790_FAN_CFG_RPM_MODE;
+		} else if (val == 1) {
+			fan_config &= ~(MAX31790_FAN_CFG_CTRL_MON | MAX31790_FAN_CFG_RPM_MODE);
+		} else if (val == 2) {
+			fan_config &= ~MAX31790_FAN_CFG_CTRL_MON;
+			/*
+			 * The chip sets MAX31790_FAN_CFG_TACH_INPUT_EN on its
+			 * own if MAX31790_FAN_CFG_RPM_MODE is set.
+			 * Do it here as well to reflect the actual register
+			 * value in the cache.
+			 */
+			fan_config |= (MAX31790_FAN_CFG_RPM_MODE | MAX31790_FAN_CFG_TACH_INPUT_EN);
+		} else {
+			err = -EINVAL;
+			break;
+		}
+		if (fan_config != data->fan_config[channel]) {
+			err = i2c_smbus_write_byte_data(client, MAX31790_REG_FAN_CONFIG(channel),
+							fan_config);
+			if (!err)
+				data->fan_config[channel] = fan_config;
+		}
+		break;
+	default:
+		err = -EOPNOTSUPP;
+		break;
+	}
+	return err;
+}
+
+static umode_t max31790_pwm_is_visible(const void *_data, u32 attr, int channel)
+{
+	const struct max31790_data *data = _data;
+	u8 fan_config = data->fan_config[channel];
+
+	switch (attr) {
+	case hwmon_pwm_input:
+	case hwmon_pwm_enable:
+		if (!(fan_config & MAX31790_FAN_CFG_TACH_INPUT))
+			return 0644;
+		return 0;
+	default:
+		return 0;
+	}
+}
+
+static int max31790_read(struct device *dev, enum hwmon_sensor_types type,
+			 u32 attr, int channel, long *val)
+{
+	switch (type) {
+	case hwmon_fan:
+		return max31790_read_fan(dev, attr, channel, val);
+	case hwmon_pwm:
+		return max31790_read_pwm(dev, attr, channel, val);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int max31790_write(struct device *dev, enum hwmon_sensor_types type,
+			  u32 attr, int channel, long val)
+{
+	switch (type) {
+	case hwmon_fan:
+		return max31790_write_fan(dev, attr, channel, val);
+	case hwmon_pwm:
+		return max31790_write_pwm(dev, attr, channel, val);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static umode_t max31790_is_visible(const void *data,
+				   enum hwmon_sensor_types type,
+				   u32 attr, int channel)
+{
+	switch (type) {
+	case hwmon_fan:
+		return max31790_fan_is_visible(data, attr, channel);
+	case hwmon_pwm:
+		return max31790_pwm_is_visible(data, attr, channel);
+	default:
+		return 0;
+	}
+}
+
+static const struct hwmon_channel_info * const max31790_info[] = {
+	HWMON_CHANNEL_INFO(fan,
+			   HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_FAULT | HWMON_F_ENABLE,
+			   HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_FAULT | HWMON_F_ENABLE,
+			   HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_FAULT | HWMON_F_ENABLE,
+			   HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_FAULT | HWMON_F_ENABLE,
+			   HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_FAULT | HWMON_F_ENABLE,
+			   HWMON_F_INPUT | HWMON_F_TARGET | HWMON_F_FAULT | HWMON_F_ENABLE,
+			   HWMON_F_INPUT | HWMON_F_FAULT,
+			   HWMON_F_INPUT | HWMON_F_FAULT,
+			   HWMON_F_INPUT | HWMON_F_FAULT,
+			   HWMON_F_INPUT | HWMON_F_FAULT,
+			   HWMON_F_INPUT | HWMON_F_FAULT,
+			   HWMON_F_INPUT | HWMON_F_FAULT),
+	HWMON_CHANNEL_INFO(pwm,
+			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
+			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
+			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
+			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
+			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
+			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE),
+	NULL
+};
+
+static const struct hwmon_ops max31790_hwmon_ops = {
+	.is_visible = max31790_is_visible,
+	.read = max31790_read,
+	.write = max31790_write,
+};
+
+static const struct hwmon_chip_info max31790_chip_info = {
+	.ops = &max31790_hwmon_ops,
+	.info = max31790_info,
+};
+
+static int max31790_init_client(struct i2c_client *client,
+				struct max31790_data *data)
+{
+	int i, rv;
+
+	for (i = 0; i < NR_CHANNEL; i++) {
+		rv = i2c_smbus_read_byte_data(client,
+				MAX31790_REG_FAN_CONFIG(i));
+		if (rv < 0)
+			return rv;
+		data->fan_config[i] = rv;
+
+		rv = i2c_smbus_read_byte_data(client,
+				MAX31790_REG_FAN_DYNAMICS(i));
+		if (rv < 0)
+			return rv;
+		data->fan_dynamics[i] = rv;
+	}
+
+	return 0;
+}
+
+static int max31790_probe(struct i2c_client *client)
+{
+	struct i2c_adapter *adapter = client->adapter;
+	struct device *dev = &client->dev;
+	struct max31790_data *data;
+	struct device *hwmon_dev;
+	int err;
+
+	if (!i2c_check_functionality(adapter,
+			I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA))
+		return -ENODEV;
+
+	data = devm_kzalloc(dev, sizeof(struct max31790_data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->client = client;
+
+	/*
+	 * Initialize the max31790 chip
+	 */
+	err = max31790_init_client(client, data);
+	if (err)
+		return err;
+
+	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
+							 data,
+							 &max31790_chip_info,
+							 NULL);
+
+	return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+static const struct i2c_device_id max31790_id[] = {
+	{ .name = "max31790" },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, max31790_id);
+
+static struct i2c_driver max31790_driver = {
+	.probe		= max31790_probe,
+	.driver = {
+		.name	= "max31790",
+	},
+	.id_table	= max31790_id,
+};
+
+module_i2c_driver(max31790_driver);
+
+MODULE_AUTHOR("Il Han <corone.il.han@gmail.com>");
+MODULE_DESCRIPTION("MAX31790 sensor driver");
+MODULE_LICENSE("GPL");