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, 381 insertions, 0 deletions

diff --git a/drivers/gpio/gpio-pmic-eic-sprd.c b/drivers/gpio/gpio-pmic-eic-sprd.c
new file mode 100644
index 000000000..cb015fb5c
--- /dev/null
+++ b/drivers/gpio/gpio-pmic-eic-sprd.c
@@ -0,0 +1,381 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018 Spreadtrum Communications Inc.
+ * Copyright (C) 2018 Linaro Ltd.
+ */
+
+#include <linux/gpio/driver.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+/* EIC registers definition */
+#define SPRD_PMIC_EIC_DATA		0x0
+#define SPRD_PMIC_EIC_DMSK		0x4
+#define SPRD_PMIC_EIC_IEV		0x14
+#define SPRD_PMIC_EIC_IE		0x18
+#define SPRD_PMIC_EIC_RIS		0x1c
+#define SPRD_PMIC_EIC_MIS		0x20
+#define SPRD_PMIC_EIC_IC		0x24
+#define SPRD_PMIC_EIC_TRIG		0x28
+#define SPRD_PMIC_EIC_CTRL0		0x40
+
+/*
+ * The PMIC EIC controller only has one bank, and each bank now can contain
+ * 16 EICs.
+ */
+#define SPRD_PMIC_EIC_PER_BANK_NR	16
+#define SPRD_PMIC_EIC_NR		SPRD_PMIC_EIC_PER_BANK_NR
+#define SPRD_PMIC_EIC_DATA_MASK		GENMASK(15, 0)
+#define SPRD_PMIC_EIC_BIT(x)		((x) & (SPRD_PMIC_EIC_PER_BANK_NR - 1))
+#define SPRD_PMIC_EIC_DBNC_MASK		GENMASK(11, 0)
+
+/*
+ * These registers are modified under the irq bus lock and cached to avoid
+ * unnecessary writes in bus_sync_unlock.
+ */
+enum {
+	REG_IEV,
+	REG_IE,
+	REG_TRIG,
+	CACHE_NR_REGS
+};
+
+/**
+ * struct sprd_pmic_eic - PMIC EIC controller
+ * @chip: the gpio_chip structure.
+ * @map:  the regmap from the parent device.
+ * @offset: the EIC controller's offset address of the PMIC.
+ * @reg: the array to cache the EIC registers.
+ * @buslock: for bus lock/sync and unlock.
+ * @irq: the interrupt number of the PMIC EIC conteroller.
+ */
+struct sprd_pmic_eic {
+	struct gpio_chip chip;
+	struct regmap *map;
+	u32 offset;
+	u8 reg[CACHE_NR_REGS];
+	struct mutex buslock;
+	int irq;
+};
+
+static void sprd_pmic_eic_update(struct gpio_chip *chip, unsigned int offset,
+				 u16 reg, unsigned int val)
+{
+	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
+	u32 shift = SPRD_PMIC_EIC_BIT(offset);
+
+	regmap_update_bits(pmic_eic->map, pmic_eic->offset + reg,
+			   BIT(shift), val << shift);
+}
+
+static int sprd_pmic_eic_read(struct gpio_chip *chip, unsigned int offset,
+			      u16 reg)
+{
+	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
+	u32 value;
+	int ret;
+
+	ret = regmap_read(pmic_eic->map, pmic_eic->offset + reg, &value);
+	if (ret)
+		return ret;
+
+	return !!(value & BIT(SPRD_PMIC_EIC_BIT(offset)));
+}
+
+static int sprd_pmic_eic_request(struct gpio_chip *chip, unsigned int offset)
+{
+	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_DMSK, 1);
+	return 0;
+}
+
+static void sprd_pmic_eic_free(struct gpio_chip *chip, unsigned int offset)
+{
+	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_DMSK, 0);
+}
+
+static int sprd_pmic_eic_get(struct gpio_chip *chip, unsigned int offset)
+{
+	return sprd_pmic_eic_read(chip, offset, SPRD_PMIC_EIC_DATA);
+}
+
+static int sprd_pmic_eic_direction_input(struct gpio_chip *chip,
+					 unsigned int offset)
+{
+	/* EICs are always input, nothing need to do here. */
+	return 0;
+}
+
+static int sprd_pmic_eic_set_debounce(struct gpio_chip *chip,
+				      unsigned int offset,
+				      unsigned int debounce)
+{
+	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
+	u32 reg, value;
+	int ret;
+
+	reg = SPRD_PMIC_EIC_CTRL0 + SPRD_PMIC_EIC_BIT(offset) * 0x4;
+	ret = regmap_read(pmic_eic->map, pmic_eic->offset + reg, &value);
+	if (ret)
+		return ret;
+
+	value &= ~SPRD_PMIC_EIC_DBNC_MASK;
+	value |= (debounce / 1000) & SPRD_PMIC_EIC_DBNC_MASK;
+	return regmap_write(pmic_eic->map, pmic_eic->offset + reg, value);
+}
+
+static int sprd_pmic_eic_set_config(struct gpio_chip *chip, unsigned int offset,
+				    unsigned long config)
+{
+	unsigned long param = pinconf_to_config_param(config);
+	u32 arg = pinconf_to_config_argument(config);
+
+	if (param == PIN_CONFIG_INPUT_DEBOUNCE)
+		return sprd_pmic_eic_set_debounce(chip, offset, arg);
+
+	return -ENOTSUPP;
+}
+
+static void sprd_pmic_eic_irq_mask(struct irq_data *data)
+{
+	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
+	u32 offset = irqd_to_hwirq(data);
+
+	pmic_eic->reg[REG_IE] &= ~BIT(offset);
+	pmic_eic->reg[REG_TRIG] &= ~BIT(offset);
+
+	gpiochip_disable_irq(chip, offset);
+}
+
+static void sprd_pmic_eic_irq_unmask(struct irq_data *data)
+{
+	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
+	u32 offset = irqd_to_hwirq(data);
+
+	gpiochip_enable_irq(chip, offset);
+
+	pmic_eic->reg[REG_IE] |= BIT(offset);
+	pmic_eic->reg[REG_TRIG] |= BIT(offset);
+}
+
+static int sprd_pmic_eic_irq_set_type(struct irq_data *data,
+				      unsigned int flow_type)
+{
+	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
+	u32 offset = irqd_to_hwirq(data);
+
+	switch (flow_type) {
+	case IRQ_TYPE_LEVEL_HIGH:
+		pmic_eic->reg[REG_IEV] |= BIT(offset);
+		break;
+	case IRQ_TYPE_LEVEL_LOW:
+		pmic_eic->reg[REG_IEV] &= ~BIT(offset);
+		break;
+	case IRQ_TYPE_EDGE_RISING:
+	case IRQ_TYPE_EDGE_FALLING:
+	case IRQ_TYPE_EDGE_BOTH:
+		/*
+		 * Will set the trigger level according to current EIC level
+		 * in irq_bus_sync_unlock() interface, so here nothing to do.
+		 */
+		break;
+	default:
+		return -ENOTSUPP;
+	}
+
+	return 0;
+}
+
+static void sprd_pmic_eic_bus_lock(struct irq_data *data)
+{
+	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
+
+	mutex_lock(&pmic_eic->buslock);
+}
+
+static void sprd_pmic_eic_bus_sync_unlock(struct irq_data *data)
+{
+	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+	struct sprd_pmic_eic *pmic_eic = gpiochip_get_data(chip);
+	u32 trigger = irqd_get_trigger_type(data);
+	u32 offset = irqd_to_hwirq(data);
+	int state;
+
+	/* Set irq type */
+	if (trigger & IRQ_TYPE_EDGE_BOTH) {
+		state = sprd_pmic_eic_get(chip, offset);
+		if (state)
+			sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IEV, 0);
+		else
+			sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IEV, 1);
+	} else {
+		sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IEV,
+				     !!(pmic_eic->reg[REG_IEV] & BIT(offset)));
+	}
+
+	/* Set irq unmask */
+	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IE,
+			     !!(pmic_eic->reg[REG_IE] & BIT(offset)));
+	/* Generate trigger start pulse for debounce EIC */
+	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_TRIG,
+			     !!(pmic_eic->reg[REG_TRIG] & BIT(offset)));
+
+	mutex_unlock(&pmic_eic->buslock);
+}
+
+static void sprd_pmic_eic_toggle_trigger(struct gpio_chip *chip,
+					 unsigned int irq, unsigned int offset)
+{
+	u32 trigger = irq_get_trigger_type(irq);
+	int state, post_state;
+
+	if (!(trigger & IRQ_TYPE_EDGE_BOTH))
+		return;
+
+	state = sprd_pmic_eic_get(chip, offset);
+retry:
+	if (state)
+		sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IEV, 0);
+	else
+		sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IEV, 1);
+
+	post_state = sprd_pmic_eic_get(chip, offset);
+	if (state != post_state) {
+		dev_warn(chip->parent, "PMIC EIC level was changed.\n");
+		state = post_state;
+		goto retry;
+	}
+
+	/* Set irq unmask */
+	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_IE, 1);
+	/* Generate trigger start pulse for debounce EIC */
+	sprd_pmic_eic_update(chip, offset, SPRD_PMIC_EIC_TRIG, 1);
+}
+
+static irqreturn_t sprd_pmic_eic_irq_handler(int irq, void *data)
+{
+	struct sprd_pmic_eic *pmic_eic = data;
+	struct gpio_chip *chip = &pmic_eic->chip;
+	unsigned long status;
+	u32 n, girq, val;
+	int ret;
+
+	ret = regmap_read(pmic_eic->map, pmic_eic->offset + SPRD_PMIC_EIC_MIS,
+			  &val);
+	if (ret)
+		return IRQ_RETVAL(ret);
+
+	status = val & SPRD_PMIC_EIC_DATA_MASK;
+
+	for_each_set_bit(n, &status, chip->ngpio) {
+		/* Clear the interrupt */
+		sprd_pmic_eic_update(chip, n, SPRD_PMIC_EIC_IC, 1);
+
+		girq = irq_find_mapping(chip->irq.domain, n);
+		handle_nested_irq(girq);
+
+		/*
+		 * The PMIC EIC can only support level trigger, so we can
+		 * toggle the level trigger to emulate the edge trigger.
+		 */
+		sprd_pmic_eic_toggle_trigger(chip, girq, n);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static const struct irq_chip pmic_eic_irq_chip = {
+	.name			= "sprd-pmic-eic",
+	.irq_mask		= sprd_pmic_eic_irq_mask,
+	.irq_unmask		= sprd_pmic_eic_irq_unmask,
+	.irq_set_type		= sprd_pmic_eic_irq_set_type,
+	.irq_bus_lock		= sprd_pmic_eic_bus_lock,
+	.irq_bus_sync_unlock	= sprd_pmic_eic_bus_sync_unlock,
+	.flags			= IRQCHIP_SKIP_SET_WAKE | IRQCHIP_IMMUTABLE,
+	GPIOCHIP_IRQ_RESOURCE_HELPERS,
+};
+
+static int sprd_pmic_eic_probe(struct platform_device *pdev)
+{
+	struct gpio_irq_chip *irq;
+	struct sprd_pmic_eic *pmic_eic;
+	int ret;
+
+	pmic_eic = devm_kzalloc(&pdev->dev, sizeof(*pmic_eic), GFP_KERNEL);
+	if (!pmic_eic)
+		return -ENOMEM;
+
+	mutex_init(&pmic_eic->buslock);
+
+	pmic_eic->irq = platform_get_irq(pdev, 0);
+	if (pmic_eic->irq < 0)
+		return pmic_eic->irq;
+
+	pmic_eic->map = dev_get_regmap(pdev->dev.parent, NULL);
+	if (!pmic_eic->map)
+		return -ENODEV;
+
+	ret = of_property_read_u32(pdev->dev.of_node, "reg", &pmic_eic->offset);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to get PMIC EIC base address.\n");
+		return ret;
+	}
+
+	ret = devm_request_threaded_irq(&pdev->dev, pmic_eic->irq, NULL,
+					sprd_pmic_eic_irq_handler,
+					IRQF_ONESHOT | IRQF_NO_SUSPEND,
+					dev_name(&pdev->dev), pmic_eic);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to request PMIC EIC IRQ.\n");
+		return ret;
+	}
+
+	pmic_eic->chip.label = dev_name(&pdev->dev);
+	pmic_eic->chip.ngpio = SPRD_PMIC_EIC_NR;
+	pmic_eic->chip.base = -1;
+	pmic_eic->chip.parent = &pdev->dev;
+	pmic_eic->chip.direction_input = sprd_pmic_eic_direction_input;
+	pmic_eic->chip.request = sprd_pmic_eic_request;
+	pmic_eic->chip.free = sprd_pmic_eic_free;
+	pmic_eic->chip.set_config = sprd_pmic_eic_set_config;
+	pmic_eic->chip.get = sprd_pmic_eic_get;
+	pmic_eic->chip.can_sleep = true;
+
+	irq = &pmic_eic->chip.irq;
+	gpio_irq_chip_set_chip(irq, &pmic_eic_irq_chip);
+	irq->threaded = true;
+
+	ret = devm_gpiochip_add_data(&pdev->dev, &pmic_eic->chip, pmic_eic);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Could not register gpiochip %d.\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct of_device_id sprd_pmic_eic_of_match[] = {
+	{ .compatible = "sprd,sc2731-eic", },
+	{ /* end of list */ }
+};
+MODULE_DEVICE_TABLE(of, sprd_pmic_eic_of_match);
+
+static struct platform_driver sprd_pmic_eic_driver = {
+	.probe = sprd_pmic_eic_probe,
+	.driver = {
+		.name = "sprd-pmic-eic",
+		.of_match_table	= sprd_pmic_eic_of_match,
+	},
+};
+
+module_platform_driver(sprd_pmic_eic_driver);
+
+MODULE_DESCRIPTION("Spreadtrum PMIC EIC driver");
+MODULE_LICENSE("GPL v2");