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, 387 insertions, 0 deletions

diff --git a/drivers/gpio/gpio-em.c b/drivers/gpio/gpio-em.c
new file mode 100644
index 000000000..a214b0672
--- /dev/null
+++ b/drivers/gpio/gpio-em.c
@@ -0,0 +1,387 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Emma Mobile GPIO Support - GIO
+ *
+ *  Copyright (C) 2012 Magnus Damm
+ */
+
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/bitops.h>
+#include <linux/err.h>
+#include <linux/gpio/driver.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/pinctrl/consumer.h>
+
+struct em_gio_priv {
+	void __iomem *base0;
+	void __iomem *base1;
+	spinlock_t sense_lock;
+	struct platform_device *pdev;
+	struct gpio_chip gpio_chip;
+	struct irq_chip irq_chip;
+	struct irq_domain *irq_domain;
+};
+
+#define GIO_E1 0x00
+#define GIO_E0 0x04
+#define GIO_EM 0x04
+#define GIO_OL 0x08
+#define GIO_OH 0x0c
+#define GIO_I 0x10
+#define GIO_IIA 0x14
+#define GIO_IEN 0x18
+#define GIO_IDS 0x1c
+#define GIO_IIM 0x1c
+#define GIO_RAW 0x20
+#define GIO_MST 0x24
+#define GIO_IIR 0x28
+
+#define GIO_IDT0 0x40
+#define GIO_IDT1 0x44
+#define GIO_IDT2 0x48
+#define GIO_IDT3 0x4c
+#define GIO_RAWBL 0x50
+#define GIO_RAWBH 0x54
+#define GIO_IRBL 0x58
+#define GIO_IRBH 0x5c
+
+#define GIO_IDT(n) (GIO_IDT0 + ((n) * 4))
+
+static inline unsigned long em_gio_read(struct em_gio_priv *p, int offs)
+{
+	if (offs < GIO_IDT0)
+		return ioread32(p->base0 + offs);
+	else
+		return ioread32(p->base1 + (offs - GIO_IDT0));
+}
+
+static inline void em_gio_write(struct em_gio_priv *p, int offs,
+				unsigned long value)
+{
+	if (offs < GIO_IDT0)
+		iowrite32(value, p->base0 + offs);
+	else
+		iowrite32(value, p->base1 + (offs - GIO_IDT0));
+}
+
+static void em_gio_irq_disable(struct irq_data *d)
+{
+	struct em_gio_priv *p = irq_data_get_irq_chip_data(d);
+
+	em_gio_write(p, GIO_IDS, BIT(irqd_to_hwirq(d)));
+}
+
+static void em_gio_irq_enable(struct irq_data *d)
+{
+	struct em_gio_priv *p = irq_data_get_irq_chip_data(d);
+
+	em_gio_write(p, GIO_IEN, BIT(irqd_to_hwirq(d)));
+}
+
+static int em_gio_irq_reqres(struct irq_data *d)
+{
+	struct em_gio_priv *p = irq_data_get_irq_chip_data(d);
+	int ret;
+
+	ret = gpiochip_lock_as_irq(&p->gpio_chip, irqd_to_hwirq(d));
+	if (ret) {
+		dev_err(p->gpio_chip.parent,
+			"unable to lock HW IRQ %lu for IRQ\n",
+			irqd_to_hwirq(d));
+		return ret;
+	}
+	return 0;
+}
+
+static void em_gio_irq_relres(struct irq_data *d)
+{
+	struct em_gio_priv *p = irq_data_get_irq_chip_data(d);
+
+	gpiochip_unlock_as_irq(&p->gpio_chip, irqd_to_hwirq(d));
+}
+
+
+#define GIO_ASYNC(x) (x + 8)
+
+static unsigned char em_gio_sense_table[IRQ_TYPE_SENSE_MASK + 1] = {
+	[IRQ_TYPE_EDGE_RISING] = GIO_ASYNC(0x00),
+	[IRQ_TYPE_EDGE_FALLING] = GIO_ASYNC(0x01),
+	[IRQ_TYPE_LEVEL_HIGH] = GIO_ASYNC(0x02),
+	[IRQ_TYPE_LEVEL_LOW] = GIO_ASYNC(0x03),
+	[IRQ_TYPE_EDGE_BOTH] = GIO_ASYNC(0x04),
+};
+
+static int em_gio_irq_set_type(struct irq_data *d, unsigned int type)
+{
+	unsigned char value = em_gio_sense_table[type & IRQ_TYPE_SENSE_MASK];
+	struct em_gio_priv *p = irq_data_get_irq_chip_data(d);
+	unsigned int reg, offset, shift;
+	unsigned long flags;
+	unsigned long tmp;
+
+	if (!value)
+		return -EINVAL;
+
+	offset = irqd_to_hwirq(d);
+
+	pr_debug("gio: sense irq = %d, mode = %d\n", offset, value);
+
+	/* 8 x 4 bit fields in 4 IDT registers */
+	reg = GIO_IDT(offset >> 3);
+	shift = (offset & 0x07) << 4;
+
+	spin_lock_irqsave(&p->sense_lock, flags);
+
+	/* disable the interrupt in IIA */
+	tmp = em_gio_read(p, GIO_IIA);
+	tmp &= ~BIT(offset);
+	em_gio_write(p, GIO_IIA, tmp);
+
+	/* change the sense setting in IDT */
+	tmp = em_gio_read(p, reg);
+	tmp &= ~(0xf << shift);
+	tmp |= value << shift;
+	em_gio_write(p, reg, tmp);
+
+	/* clear pending interrupts */
+	em_gio_write(p, GIO_IIR, BIT(offset));
+
+	/* enable the interrupt in IIA */
+	tmp = em_gio_read(p, GIO_IIA);
+	tmp |= BIT(offset);
+	em_gio_write(p, GIO_IIA, tmp);
+
+	spin_unlock_irqrestore(&p->sense_lock, flags);
+
+	return 0;
+}
+
+static irqreturn_t em_gio_irq_handler(int irq, void *dev_id)
+{
+	struct em_gio_priv *p = dev_id;
+	unsigned long pending;
+	unsigned int offset, irqs_handled = 0;
+
+	while ((pending = em_gio_read(p, GIO_MST))) {
+		offset = __ffs(pending);
+		em_gio_write(p, GIO_IIR, BIT(offset));
+		generic_handle_domain_irq(p->irq_domain, offset);
+		irqs_handled++;
+	}
+
+	return irqs_handled ? IRQ_HANDLED : IRQ_NONE;
+}
+
+static inline struct em_gio_priv *gpio_to_priv(struct gpio_chip *chip)
+{
+	return gpiochip_get_data(chip);
+}
+
+static int em_gio_direction_input(struct gpio_chip *chip, unsigned offset)
+{
+	em_gio_write(gpio_to_priv(chip), GIO_E0, BIT(offset));
+	return 0;
+}
+
+static int em_gio_get(struct gpio_chip *chip, unsigned offset)
+{
+	return !!(em_gio_read(gpio_to_priv(chip), GIO_I) & BIT(offset));
+}
+
+static void __em_gio_set(struct gpio_chip *chip, unsigned int reg,
+			 unsigned shift, int value)
+{
+	/* upper 16 bits contains mask and lower 16 actual value */
+	em_gio_write(gpio_to_priv(chip), reg,
+		     (BIT(shift + 16)) | (value << shift));
+}
+
+static int em_gio_set(struct gpio_chip *chip, unsigned int offset, int value)
+{
+	/* output is split into two registers */
+	if (offset < 16)
+		__em_gio_set(chip, GIO_OL, offset, value);
+	else
+		__em_gio_set(chip, GIO_OH, offset - 16, value);
+
+	return 0;
+}
+
+static int em_gio_direction_output(struct gpio_chip *chip, unsigned offset,
+				   int value)
+{
+	/* write GPIO value to output before selecting output mode of pin */
+	em_gio_set(chip, offset, value);
+	em_gio_write(gpio_to_priv(chip), GIO_E1, BIT(offset));
+	return 0;
+}
+
+static int em_gio_to_irq(struct gpio_chip *chip, unsigned offset)
+{
+	return irq_create_mapping(gpio_to_priv(chip)->irq_domain, offset);
+}
+
+static void em_gio_free(struct gpio_chip *chip, unsigned offset)
+{
+	pinctrl_gpio_free(chip, offset);
+
+	/* Set the GPIO as an input to ensure that the next GPIO request won't
+	* drive the GPIO pin as an output.
+	*/
+	em_gio_direction_input(chip, offset);
+}
+
+static int em_gio_irq_domain_map(struct irq_domain *h, unsigned int irq,
+				 irq_hw_number_t hwirq)
+{
+	struct em_gio_priv *p = h->host_data;
+
+	pr_debug("gio: map hw irq = %d, irq = %d\n", (int)hwirq, irq);
+
+	irq_set_chip_data(irq, h->host_data);
+	irq_set_chip_and_handler(irq, &p->irq_chip, handle_level_irq);
+	return 0;
+}
+
+static const struct irq_domain_ops em_gio_irq_domain_ops = {
+	.map	= em_gio_irq_domain_map,
+	.xlate	= irq_domain_xlate_twocell,
+};
+
+static void em_gio_irq_domain_remove(void *data)
+{
+	struct irq_domain *domain = data;
+
+	irq_domain_remove(domain);
+}
+
+static int em_gio_probe(struct platform_device *pdev)
+{
+	struct em_gio_priv *p;
+	struct gpio_chip *gpio_chip;
+	struct irq_chip *irq_chip;
+	struct device *dev = &pdev->dev;
+	const char *name = dev_name(dev);
+	unsigned int ngpios;
+	int irq[2], ret;
+
+	p = devm_kzalloc(dev, sizeof(*p), GFP_KERNEL);
+	if (!p)
+		return -ENOMEM;
+
+	p->pdev = pdev;
+	platform_set_drvdata(pdev, p);
+	spin_lock_init(&p->sense_lock);
+
+	irq[0] = platform_get_irq(pdev, 0);
+	if (irq[0] < 0)
+		return irq[0];
+
+	irq[1] = platform_get_irq(pdev, 1);
+	if (irq[1] < 0)
+		return irq[1];
+
+	p->base0 = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(p->base0))
+		return PTR_ERR(p->base0);
+
+	p->base1 = devm_platform_ioremap_resource(pdev, 1);
+	if (IS_ERR(p->base1))
+		return PTR_ERR(p->base1);
+
+	if (of_property_read_u32(dev->of_node, "ngpios", &ngpios)) {
+		dev_err(dev, "Missing ngpios OF property\n");
+		return -EINVAL;
+	}
+
+	gpio_chip = &p->gpio_chip;
+	gpio_chip->direction_input = em_gio_direction_input;
+	gpio_chip->get = em_gio_get;
+	gpio_chip->direction_output = em_gio_direction_output;
+	gpio_chip->set = em_gio_set;
+	gpio_chip->to_irq = em_gio_to_irq;
+	gpio_chip->request = pinctrl_gpio_request;
+	gpio_chip->free = em_gio_free;
+	gpio_chip->label = name;
+	gpio_chip->parent = dev;
+	gpio_chip->owner = THIS_MODULE;
+	gpio_chip->base = -1;
+	gpio_chip->ngpio = ngpios;
+
+	irq_chip = &p->irq_chip;
+	irq_chip->name = "gpio-em";
+	irq_chip->irq_mask = em_gio_irq_disable;
+	irq_chip->irq_unmask = em_gio_irq_enable;
+	irq_chip->irq_set_type = em_gio_irq_set_type;
+	irq_chip->irq_request_resources = em_gio_irq_reqres;
+	irq_chip->irq_release_resources = em_gio_irq_relres;
+	irq_chip->flags	= IRQCHIP_SKIP_SET_WAKE | IRQCHIP_MASK_ON_SUSPEND;
+
+	p->irq_domain = irq_domain_create_simple(dev_fwnode(dev), ngpios, 0,
+						 &em_gio_irq_domain_ops, p);
+	if (!p->irq_domain) {
+		dev_err(dev, "cannot initialize irq domain\n");
+		return -ENXIO;
+	}
+
+	ret = devm_add_action_or_reset(dev, em_gio_irq_domain_remove,
+				       p->irq_domain);
+	if (ret)
+		return ret;
+
+	if (devm_request_irq(dev, irq[0], em_gio_irq_handler, 0, name, p)) {
+		dev_err(dev, "failed to request low IRQ\n");
+		return -ENOENT;
+	}
+
+	if (devm_request_irq(dev, irq[1], em_gio_irq_handler, 0, name, p)) {
+		dev_err(dev, "failed to request high IRQ\n");
+		return -ENOENT;
+	}
+
+	ret = devm_gpiochip_add_data(dev, gpio_chip, p);
+	if (ret) {
+		dev_err(dev, "failed to add GPIO controller\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct of_device_id em_gio_dt_ids[] = {
+	{ .compatible = "renesas,em-gio", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, em_gio_dt_ids);
+
+static struct platform_driver em_gio_device_driver = {
+	.probe		= em_gio_probe,
+	.driver		= {
+		.name	= "em_gio",
+		.of_match_table = em_gio_dt_ids,
+	}
+};
+
+static int __init em_gio_init(void)
+{
+	return platform_driver_register(&em_gio_device_driver);
+}
+postcore_initcall(em_gio_init);
+
+static void __exit em_gio_exit(void)
+{
+	platform_driver_unregister(&em_gio_device_driver);
+}
+module_exit(em_gio_exit);
+
+MODULE_AUTHOR("Magnus Damm");
+MODULE_DESCRIPTION("Renesas Emma Mobile GIO Driver");
+MODULE_LICENSE("GPL v2");