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, 346 insertions, 0 deletions

diff --git a/drivers/mfd/adp5520.c b/drivers/mfd/adp5520.c
new file mode 100644
index 000000000..bd6f4965e
--- /dev/null
+++ b/drivers/mfd/adp5520.c
@@ -0,0 +1,346 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Base driver for Analog Devices ADP5520/ADP5501 MFD PMICs
+ * LCD Backlight: drivers/video/backlight/adp5520_bl
+ * LEDs		: drivers/led/leds-adp5520
+ * GPIO		: drivers/gpio/adp5520-gpio (ADP5520 only)
+ * Keys		: drivers/input/keyboard/adp5520-keys (ADP5520 only)
+ *
+ * Copyright 2009 Analog Devices Inc.
+ *
+ * Author: Michael Hennerich <michael.hennerich@analog.com>
+ *
+ * Derived from da903x:
+ * Copyright (C) 2008 Compulab, Ltd.
+ *	Mike Rapoport <mike@compulab.co.il>
+ *
+ * Copyright (C) 2006-2008 Marvell International Ltd.
+ *	Eric Miao <eric.miao@marvell.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+
+#include <linux/mfd/adp5520.h>
+
+struct adp5520_chip {
+	struct i2c_client *client;
+	struct device *dev;
+	struct mutex lock;
+	struct blocking_notifier_head notifier_list;
+	int irq;
+	unsigned long id;
+	uint8_t mode;
+};
+
+static int __adp5520_read(struct i2c_client *client,
+				int reg, uint8_t *val)
+{
+	int ret;
+
+	ret = i2c_smbus_read_byte_data(client, reg);
+	if (ret < 0) {
+		dev_err(&client->dev, "failed reading at 0x%02x\n", reg);
+		return ret;
+	}
+
+	*val = (uint8_t)ret;
+	return 0;
+}
+
+static int __adp5520_write(struct i2c_client *client,
+				 int reg, uint8_t val)
+{
+	int ret;
+
+	ret = i2c_smbus_write_byte_data(client, reg, val);
+	if (ret < 0) {
+		dev_err(&client->dev, "failed writing 0x%02x to 0x%02x\n",
+				val, reg);
+		return ret;
+	}
+	return 0;
+}
+
+static int __adp5520_ack_bits(struct i2c_client *client, int reg,
+			      uint8_t bit_mask)
+{
+	struct adp5520_chip *chip = i2c_get_clientdata(client);
+	uint8_t reg_val;
+	int ret;
+
+	mutex_lock(&chip->lock);
+
+	ret = __adp5520_read(client, reg, &reg_val);
+
+	if (!ret) {
+		reg_val |= bit_mask;
+		ret = __adp5520_write(client, reg, reg_val);
+	}
+
+	mutex_unlock(&chip->lock);
+	return ret;
+}
+
+int adp5520_write(struct device *dev, int reg, uint8_t val)
+{
+	return __adp5520_write(to_i2c_client(dev), reg, val);
+}
+EXPORT_SYMBOL_GPL(adp5520_write);
+
+int adp5520_read(struct device *dev, int reg, uint8_t *val)
+{
+	return __adp5520_read(to_i2c_client(dev), reg, val);
+}
+EXPORT_SYMBOL_GPL(adp5520_read);
+
+int adp5520_set_bits(struct device *dev, int reg, uint8_t bit_mask)
+{
+	struct adp5520_chip *chip = dev_get_drvdata(dev);
+	uint8_t reg_val;
+	int ret;
+
+	mutex_lock(&chip->lock);
+
+	ret = __adp5520_read(chip->client, reg, &reg_val);
+
+	if (!ret && ((reg_val & bit_mask) != bit_mask)) {
+		reg_val |= bit_mask;
+		ret = __adp5520_write(chip->client, reg, reg_val);
+	}
+
+	mutex_unlock(&chip->lock);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(adp5520_set_bits);
+
+int adp5520_clr_bits(struct device *dev, int reg, uint8_t bit_mask)
+{
+	struct adp5520_chip *chip = dev_get_drvdata(dev);
+	uint8_t reg_val;
+	int ret;
+
+	mutex_lock(&chip->lock);
+
+	ret = __adp5520_read(chip->client, reg, &reg_val);
+
+	if (!ret && (reg_val & bit_mask)) {
+		reg_val &= ~bit_mask;
+		ret = __adp5520_write(chip->client, reg, reg_val);
+	}
+
+	mutex_unlock(&chip->lock);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(adp5520_clr_bits);
+
+int adp5520_register_notifier(struct device *dev, struct notifier_block *nb,
+				unsigned int events)
+{
+	struct adp5520_chip *chip = dev_get_drvdata(dev);
+
+	if (chip->irq) {
+		adp5520_set_bits(chip->dev, ADP5520_INTERRUPT_ENABLE,
+			events & (ADP5520_KP_IEN | ADP5520_KR_IEN |
+			ADP5520_OVP_IEN | ADP5520_CMPR_IEN));
+
+		return blocking_notifier_chain_register(&chip->notifier_list,
+			 nb);
+	}
+
+	return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(adp5520_register_notifier);
+
+int adp5520_unregister_notifier(struct device *dev, struct notifier_block *nb,
+				unsigned int events)
+{
+	struct adp5520_chip *chip = dev_get_drvdata(dev);
+
+	adp5520_clr_bits(chip->dev, ADP5520_INTERRUPT_ENABLE,
+		events & (ADP5520_KP_IEN | ADP5520_KR_IEN |
+		ADP5520_OVP_IEN | ADP5520_CMPR_IEN));
+
+	return blocking_notifier_chain_unregister(&chip->notifier_list, nb);
+}
+EXPORT_SYMBOL_GPL(adp5520_unregister_notifier);
+
+static irqreturn_t adp5520_irq_thread(int irq, void *data)
+{
+	struct adp5520_chip *chip = data;
+	unsigned int events;
+	uint8_t reg_val;
+	int ret;
+
+	ret = __adp5520_read(chip->client, ADP5520_MODE_STATUS, &reg_val);
+	if (ret)
+		goto out;
+
+	events =  reg_val & (ADP5520_OVP_INT | ADP5520_CMPR_INT |
+		ADP5520_GPI_INT | ADP5520_KR_INT | ADP5520_KP_INT);
+
+	blocking_notifier_call_chain(&chip->notifier_list, events, NULL);
+	/* ACK, Sticky bits are W1C */
+	__adp5520_ack_bits(chip->client, ADP5520_MODE_STATUS, events);
+
+out:
+	return IRQ_HANDLED;
+}
+
+static int __remove_subdev(struct device *dev, void *unused)
+{
+	platform_device_unregister(to_platform_device(dev));
+	return 0;
+}
+
+static int adp5520_remove_subdevs(struct adp5520_chip *chip)
+{
+	return device_for_each_child(chip->dev, NULL, __remove_subdev);
+}
+
+static int adp5520_probe(struct i2c_client *client)
+{
+	const struct i2c_device_id *id = i2c_client_get_device_id(client);
+	struct adp5520_platform_data *pdata = dev_get_platdata(&client->dev);
+	struct platform_device *pdev;
+	struct adp5520_chip *chip;
+	int ret;
+
+	if (!i2c_check_functionality(client->adapter,
+					I2C_FUNC_SMBUS_BYTE_DATA)) {
+		dev_err(&client->dev, "SMBUS Word Data not Supported\n");
+		return -EIO;
+	}
+
+	if (pdata == NULL) {
+		dev_err(&client->dev, "missing platform data\n");
+		return -ENODEV;
+	}
+
+	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
+	if (!chip)
+		return -ENOMEM;
+
+	i2c_set_clientdata(client, chip);
+	chip->client = client;
+
+	chip->dev = &client->dev;
+	chip->irq = client->irq;
+	chip->id = id->driver_data;
+	mutex_init(&chip->lock);
+
+	if (chip->irq) {
+		BLOCKING_INIT_NOTIFIER_HEAD(&chip->notifier_list);
+
+		ret = request_threaded_irq(chip->irq, NULL, adp5520_irq_thread,
+				IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+				"adp5520", chip);
+		if (ret) {
+			dev_err(&client->dev, "failed to request irq %d\n",
+					chip->irq);
+			return ret;
+		}
+	}
+
+	ret = adp5520_write(chip->dev, ADP5520_MODE_STATUS, ADP5520_nSTNBY);
+	if (ret) {
+		dev_err(&client->dev, "failed to write\n");
+		goto out_free_irq;
+	}
+
+	if (pdata->keys) {
+		pdev = platform_device_register_data(chip->dev, "adp5520-keys",
+				chip->id, pdata->keys, sizeof(*pdata->keys));
+		if (IS_ERR(pdev)) {
+			ret = PTR_ERR(pdev);
+			goto out_remove_subdevs;
+		}
+	}
+
+	if (pdata->gpio) {
+		pdev = platform_device_register_data(chip->dev, "adp5520-gpio",
+				chip->id, pdata->gpio, sizeof(*pdata->gpio));
+		if (IS_ERR(pdev)) {
+			ret = PTR_ERR(pdev);
+			goto out_remove_subdevs;
+		}
+	}
+
+	if (pdata->leds) {
+		pdev = platform_device_register_data(chip->dev, "adp5520-led",
+				chip->id, pdata->leds, sizeof(*pdata->leds));
+		if (IS_ERR(pdev)) {
+			ret = PTR_ERR(pdev);
+			goto out_remove_subdevs;
+		}
+	}
+
+	if (pdata->backlight) {
+		pdev = platform_device_register_data(chip->dev,
+						"adp5520-backlight",
+						chip->id,
+						pdata->backlight,
+						sizeof(*pdata->backlight));
+		if (IS_ERR(pdev)) {
+			ret = PTR_ERR(pdev);
+			goto out_remove_subdevs;
+		}
+	}
+
+	return 0;
+
+out_remove_subdevs:
+	adp5520_remove_subdevs(chip);
+
+out_free_irq:
+	if (chip->irq)
+		free_irq(chip->irq, chip);
+
+	return ret;
+}
+
+static int adp5520_suspend(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct adp5520_chip *chip = dev_get_drvdata(&client->dev);
+
+	adp5520_read(chip->dev, ADP5520_MODE_STATUS, &chip->mode);
+	/* All other bits are W1C */
+	chip->mode &= ADP5520_BL_EN | ADP5520_DIM_EN | ADP5520_nSTNBY;
+	adp5520_write(chip->dev, ADP5520_MODE_STATUS, 0);
+	return 0;
+}
+
+static int adp5520_resume(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct adp5520_chip *chip = dev_get_drvdata(&client->dev);
+
+	adp5520_write(chip->dev, ADP5520_MODE_STATUS, chip->mode);
+	return 0;
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(adp5520_pm, adp5520_suspend, adp5520_resume);
+
+static const struct i2c_device_id adp5520_id[] = {
+	{ "pmic-adp5520", ID_ADP5520 },
+	{ "pmic-adp5501", ID_ADP5501 },
+	{ }
+};
+
+static struct i2c_driver adp5520_driver = {
+	.driver = {
+		.name			= "adp5520",
+		.pm			= pm_sleep_ptr(&adp5520_pm),
+		.suppress_bind_attrs	= true,
+	},
+	.probe		= adp5520_probe,
+	.id_table	= adp5520_id,
+};
+builtin_i2c_driver(adp5520_driver);