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, 399 insertions, 0 deletions

diff --git a/drivers/hwmon/max1619.c b/drivers/hwmon/max1619.c
new file mode 100644
index 000000000..77ef39e8a
--- /dev/null
+++ b/drivers/hwmon/max1619.c
@@ -0,0 +1,399 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * max1619.c - Part of lm_sensors, Linux kernel modules for hardware
+ *             monitoring
+ * Copyright (C) 2003-2004 Oleksij Rempel <bug-track@fisher-privat.net>
+ *                         Jean Delvare <jdelvare@suse.de>
+ *
+ * Based on the lm90 driver. The MAX1619 is a sensor chip made by Maxim.
+ * It reports up to two temperatures (its own plus up to
+ * one external one). Complete datasheet can be
+ * obtained from Maxim's website at:
+ *   http://pdfserv.maxim-ic.com/en/ds/MAX1619.pdf
+ */
+
+#include <linux/err.h>
+#include <linux/hwmon.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/util_macros.h>
+
+static const unsigned short normal_i2c[] = {
+	0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };
+
+#define MAX1619_REG_LOCAL_TEMP		0x00
+#define MAX1619_REG_REMOTE_TEMP		0x01
+#define MAX1619_REG_STATUS		0x02
+#define MAX1619_REG_CONFIG		0x03
+#define MAX1619_REG_CONVRATE		0x04
+#define MAX1619_REG_REMOTE_HIGH		0x07
+#define MAX1619_REG_REMOTE_LOW		0x08
+#define MAX1619_REG_REMOTE_CRIT		0x10
+#define MAX1619_REG_REMOTE_CRIT_HYST	0x11
+#define MAX1619_REG_MAN_ID		0xFE
+#define MAX1619_REG_CHIP_ID		0xFF
+
+static int get_alarms(struct regmap *regmap)
+{
+	static u32 regs[2] = { MAX1619_REG_STATUS, MAX1619_REG_CONFIG };
+	u8 regdata[2];
+	int ret;
+
+	ret = regmap_multi_reg_read(regmap, regs, regdata, 2);
+	if (ret)
+		return ret;
+
+	/* OVERT status bit may be reversed */
+	if (!(regdata[1] & 0x20))
+		regdata[0] ^= 0x02;
+
+	return regdata[0] & 0x1e;
+}
+
+static int max1619_temp_read(struct regmap *regmap, u32 attr, int channel, long *val)
+{
+	int reg = -1, alarm_bit = 0;
+	u32 temp;
+	int ret;
+
+	switch (attr) {
+	case hwmon_temp_input:
+		reg = channel ? MAX1619_REG_REMOTE_TEMP : MAX1619_REG_LOCAL_TEMP;
+		break;
+	case hwmon_temp_min:
+		reg = MAX1619_REG_REMOTE_LOW;
+		break;
+	case hwmon_temp_max:
+		reg = MAX1619_REG_REMOTE_HIGH;
+		break;
+	case hwmon_temp_crit:
+		reg = MAX1619_REG_REMOTE_CRIT;
+		break;
+	case hwmon_temp_crit_hyst:
+		reg = MAX1619_REG_REMOTE_CRIT_HYST;
+		break;
+	case hwmon_temp_min_alarm:
+		alarm_bit = 3;
+		break;
+	case hwmon_temp_max_alarm:
+		alarm_bit = 4;
+		break;
+	case hwmon_temp_crit_alarm:
+		alarm_bit = 1;
+		break;
+	case hwmon_temp_fault:
+		alarm_bit = 2;
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+	if (reg >= 0) {
+		ret = regmap_read(regmap, reg, &temp);
+		if (ret < 0)
+			return ret;
+		*val = sign_extend32(temp, 7) * 1000;
+	} else {
+		ret = get_alarms(regmap);
+		if (ret < 0)
+			return ret;
+		*val = !!(ret & BIT(alarm_bit));
+	}
+	return 0;
+}
+
+static u16 update_intervals[] = { 16000, 8000, 4000, 2000, 1000, 500, 250, 125 };
+
+static int max1619_chip_read(struct regmap *regmap, u32 attr, long *val)
+{
+	int alarms, ret;
+	u32 regval;
+
+	switch (attr) {
+	case hwmon_chip_update_interval:
+		ret = regmap_read(regmap, MAX1619_REG_CONVRATE, &regval);
+		if (ret < 0)
+			return ret;
+		*val = update_intervals[regval & 7];
+		break;
+	case hwmon_chip_alarms:
+		alarms = get_alarms(regmap);
+		if (alarms < 0)
+			return alarms;
+		*val = alarms;
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+	return 0;
+}
+
+static int max1619_read(struct device *dev, enum hwmon_sensor_types type,
+			u32 attr, int channel, long *val)
+{
+	struct regmap *regmap = dev_get_drvdata(dev);
+
+	switch (type) {
+	case hwmon_chip:
+		return max1619_chip_read(regmap, attr, val);
+	case hwmon_temp:
+		return max1619_temp_read(regmap, attr, channel, val);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int max1619_chip_write(struct regmap *regmap, u32 attr, long val)
+{
+	switch (attr) {
+	case hwmon_chip_update_interval:
+		val = find_closest_descending(val, update_intervals, ARRAY_SIZE(update_intervals));
+		return regmap_write(regmap, MAX1619_REG_CONVRATE, val);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int max1619_temp_write(struct regmap *regmap,
+			      u32 attr, int channel, long val)
+{
+	int reg;
+
+	switch (attr) {
+	case hwmon_temp_min:
+		reg = MAX1619_REG_REMOTE_LOW;
+		break;
+	case hwmon_temp_max:
+		reg = MAX1619_REG_REMOTE_HIGH;
+		break;
+	case hwmon_temp_crit:
+		reg = MAX1619_REG_REMOTE_CRIT;
+		break;
+	case hwmon_temp_crit_hyst:
+		reg = MAX1619_REG_REMOTE_CRIT_HYST;
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+	val = DIV_ROUND_CLOSEST(clamp_val(val, -128000, 127000), 1000);
+	return regmap_write(regmap, reg, val);
+}
+
+static int max1619_write(struct device *dev, enum hwmon_sensor_types type,
+			 u32 attr, int channel, long val)
+{
+	struct regmap *regmap = dev_get_drvdata(dev);
+
+	switch (type) {
+	case hwmon_chip:
+		return max1619_chip_write(regmap, attr, val);
+	case hwmon_temp:
+		return max1619_temp_write(regmap, attr, channel, val);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static umode_t max1619_is_visible(const void *_data, enum hwmon_sensor_types type,
+				  u32 attr, int channel)
+{
+	switch (type) {
+	case hwmon_chip:
+		switch (attr) {
+		case hwmon_chip_update_interval:
+			return 0644;
+		case hwmon_chip_alarms:
+			return 0444;
+		default:
+			break;
+		}
+		break;
+	case hwmon_temp:
+		switch (attr) {
+		case hwmon_temp_input:
+			return 0444;
+		case hwmon_temp_min:
+		case hwmon_temp_max:
+		case hwmon_temp_crit:
+		case hwmon_temp_crit_hyst:
+			return 0644;
+		case hwmon_temp_min_alarm:
+		case hwmon_temp_max_alarm:
+		case hwmon_temp_crit_alarm:
+		case hwmon_temp_fault:
+			return 0444;
+		default:
+			break;
+		}
+		break;
+	default:
+		break;
+	}
+	return 0;
+}
+
+static const struct hwmon_channel_info * const max1619_info[] = {
+	HWMON_CHANNEL_INFO(chip, HWMON_C_ALARMS | HWMON_C_UPDATE_INTERVAL),
+	HWMON_CHANNEL_INFO(temp,
+			   HWMON_T_INPUT,
+			   HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX |
+			   HWMON_T_CRIT | HWMON_T_CRIT_HYST |
+			   HWMON_T_MIN_ALARM | HWMON_T_MAX_ALARM |
+			   HWMON_T_CRIT_ALARM | HWMON_T_FAULT),
+	NULL
+};
+
+static const struct hwmon_ops max1619_hwmon_ops = {
+	.is_visible = max1619_is_visible,
+	.read = max1619_read,
+	.write = max1619_write,
+};
+
+static const struct hwmon_chip_info max1619_chip_info = {
+	.ops = &max1619_hwmon_ops,
+	.info = max1619_info,
+};
+
+/* Return 0 if detection is successful, -ENODEV otherwise */
+static int max1619_detect(struct i2c_client *client,
+			  struct i2c_board_info *info)
+{
+	struct i2c_adapter *adapter = client->adapter;
+	int regval;
+
+	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
+		return -ENODEV;
+
+	regval = i2c_smbus_read_byte_data(client, MAX1619_REG_CONFIG);
+	if (regval < 0 || (regval & 0x03))
+		return -ENODEV;
+	regval = i2c_smbus_read_byte_data(client, MAX1619_REG_CONVRATE);
+	if (regval < 0 || regval > 0x07)
+		return -ENODEV;
+	regval = i2c_smbus_read_byte_data(client, MAX1619_REG_STATUS);
+	if (regval < 0 || (regval & 0x61))
+		return -ENODEV;
+
+	regval = i2c_smbus_read_byte_data(client, MAX1619_REG_MAN_ID);
+	if (regval != 0x4d)
+		return -ENODEV;
+	regval = i2c_smbus_read_byte_data(client, MAX1619_REG_CHIP_ID);
+	if (regval != 0x04)
+		return -ENODEV;
+
+	strscpy(info->type, "max1619", I2C_NAME_SIZE);
+
+	return 0;
+}
+
+static int max1619_init_chip(struct regmap *regmap)
+{
+	int ret;
+
+	ret = regmap_write(regmap, MAX1619_REG_CONVRATE, 5);	/* 2 Hz */
+	if (ret)
+		return ret;
+
+	/* Start conversions */
+	return regmap_clear_bits(regmap, MAX1619_REG_CONFIG, 0x40);
+}
+
+/* regmap */
+
+static int max1619_reg_read(void *context, unsigned int reg, unsigned int *val)
+{
+	int ret;
+
+	ret = i2c_smbus_read_byte_data(context, reg);
+	if (ret < 0)
+		return ret;
+
+	*val = ret;
+	return 0;
+}
+
+static int max1619_reg_write(void *context, unsigned int reg, unsigned int val)
+{
+	int offset = reg < MAX1619_REG_REMOTE_CRIT ? 6 : 2;
+
+	return i2c_smbus_write_byte_data(context, reg + offset, val);
+}
+
+static bool max1619_regmap_is_volatile(struct device *dev, unsigned int reg)
+{
+	return reg <= MAX1619_REG_STATUS;
+}
+
+static bool max1619_regmap_is_writeable(struct device *dev, unsigned int reg)
+{
+	return reg > MAX1619_REG_STATUS && reg <= MAX1619_REG_REMOTE_CRIT_HYST;
+}
+
+static const struct regmap_config max1619_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = MAX1619_REG_REMOTE_CRIT_HYST,
+	.cache_type = REGCACHE_MAPLE,
+	.volatile_reg = max1619_regmap_is_volatile,
+	.writeable_reg = max1619_regmap_is_writeable,
+};
+
+static const struct regmap_bus max1619_regmap_bus = {
+	.reg_write = max1619_reg_write,
+	.reg_read = max1619_reg_read,
+};
+
+static int max1619_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct device *hwmon_dev;
+	struct regmap *regmap;
+	int ret;
+
+	regmap = devm_regmap_init(dev, &max1619_regmap_bus, client,
+				  &max1619_regmap_config);
+	if (IS_ERR(regmap))
+		return PTR_ERR(regmap);
+
+	ret = max1619_init_chip(regmap);
+	if (ret)
+		return ret;
+
+	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
+							 regmap, &max1619_chip_info, NULL);
+	return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+static const struct i2c_device_id max1619_id[] = {
+	{ .name = "max1619" },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, max1619_id);
+
+#ifdef CONFIG_OF
+static const struct of_device_id max1619_of_match[] = {
+	{ .compatible = "maxim,max1619", },
+	{},
+};
+
+MODULE_DEVICE_TABLE(of, max1619_of_match);
+#endif
+
+static struct i2c_driver max1619_driver = {
+	.class		= I2C_CLASS_HWMON,
+	.driver = {
+		.name	= "max1619",
+		.of_match_table = of_match_ptr(max1619_of_match),
+	},
+	.probe		= max1619_probe,
+	.id_table	= max1619_id,
+	.detect		= max1619_detect,
+	.address_list	= normal_i2c,
+};
+
+module_i2c_driver(max1619_driver);
+
+MODULE_AUTHOR("Oleksij Rempel <bug-track@fisher-privat.net>, Jean Delvare <jdelvare@suse.de>");
+MODULE_DESCRIPTION("MAX1619 sensor driver");
+MODULE_LICENSE("GPL");