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, 379 insertions, 0 deletions

diff --git a/drivers/usb/common/ulpi.c b/drivers/usb/common/ulpi.c
new file mode 100644
index 000000000..7e43429e9
--- /dev/null
+++ b/drivers/usb/common/ulpi.c
@@ -0,0 +1,379 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ulpi.c - USB ULPI PHY bus
+ *
+ * Copyright (C) 2015 Intel Corporation
+ *
+ * Author: Heikki Krogerus <heikki.krogerus@linux.intel.com>
+ */
+
+#include <linux/ulpi/interface.h>
+#include <linux/ulpi/driver.h>
+#include <linux/ulpi/regs.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/acpi.h>
+#include <linux/debugfs.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/clk/clk-conf.h>
+
+/* -------------------------------------------------------------------------- */
+
+int ulpi_read(struct ulpi *ulpi, u8 addr)
+{
+	return ulpi->ops->read(ulpi->dev.parent, addr);
+}
+EXPORT_SYMBOL_GPL(ulpi_read);
+
+int ulpi_write(struct ulpi *ulpi, u8 addr, u8 val)
+{
+	return ulpi->ops->write(ulpi->dev.parent, addr, val);
+}
+EXPORT_SYMBOL_GPL(ulpi_write);
+
+/* -------------------------------------------------------------------------- */
+
+static int ulpi_match(struct device *dev, const struct device_driver *driver)
+{
+	struct ulpi_driver *drv = to_ulpi_driver(driver);
+	struct ulpi *ulpi = to_ulpi_dev(dev);
+	const struct ulpi_device_id *id;
+
+	/*
+	 * Some ULPI devices don't have a vendor id
+	 * or provide an id_table so rely on OF match.
+	 */
+	if (ulpi->id.vendor == 0 || !drv->id_table)
+		return of_driver_match_device(dev, driver);
+
+	for (id = drv->id_table; id->vendor; id++)
+		if (id->vendor == ulpi->id.vendor &&
+		    id->product == ulpi->id.product)
+			return 1;
+
+	return 0;
+}
+
+static int ulpi_uevent(const struct device *dev, struct kobj_uevent_env *env)
+{
+	const struct ulpi *ulpi = to_ulpi_dev(dev);
+	int ret;
+
+	ret = of_device_uevent_modalias(dev, env);
+	if (ret != -ENODEV)
+		return ret;
+
+	if (add_uevent_var(env, "MODALIAS=ulpi:v%04xp%04x",
+			   ulpi->id.vendor, ulpi->id.product))
+		return -ENOMEM;
+	return 0;
+}
+
+static int ulpi_probe(struct device *dev)
+{
+	struct ulpi_driver *drv = to_ulpi_driver(dev->driver);
+	int ret;
+
+	ret = of_clk_set_defaults(dev->of_node, false);
+	if (ret < 0)
+		return ret;
+
+	return drv->probe(to_ulpi_dev(dev));
+}
+
+static void ulpi_remove(struct device *dev)
+{
+	struct ulpi_driver *drv = to_ulpi_driver(dev->driver);
+
+	if (drv->remove)
+		drv->remove(to_ulpi_dev(dev));
+}
+
+static const struct bus_type ulpi_bus = {
+	.name = "ulpi",
+	.match = ulpi_match,
+	.uevent = ulpi_uevent,
+	.probe = ulpi_probe,
+	.remove = ulpi_remove,
+};
+
+/* -------------------------------------------------------------------------- */
+
+static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
+			     char *buf)
+{
+	int len;
+	struct ulpi *ulpi = to_ulpi_dev(dev);
+
+	len = of_device_modalias(dev, buf, PAGE_SIZE);
+	if (len != -ENODEV)
+		return len;
+
+	return sprintf(buf, "ulpi:v%04xp%04x\n",
+		       ulpi->id.vendor, ulpi->id.product);
+}
+static DEVICE_ATTR_RO(modalias);
+
+static struct attribute *ulpi_dev_attrs[] = {
+	&dev_attr_modalias.attr,
+	NULL
+};
+
+static const struct attribute_group ulpi_dev_attr_group = {
+	.attrs = ulpi_dev_attrs,
+};
+
+static const struct attribute_group *ulpi_dev_attr_groups[] = {
+	&ulpi_dev_attr_group,
+	NULL
+};
+
+static void ulpi_dev_release(struct device *dev)
+{
+	of_node_put(dev->of_node);
+	kfree(to_ulpi_dev(dev));
+}
+
+static const struct device_type ulpi_dev_type = {
+	.name = "ulpi_device",
+	.groups = ulpi_dev_attr_groups,
+	.release = ulpi_dev_release,
+};
+
+/* -------------------------------------------------------------------------- */
+
+/**
+ * __ulpi_register_driver - register a driver with the ULPI bus
+ * @drv: driver being registered
+ * @module: ends up being THIS_MODULE
+ *
+ * Registers a driver with the ULPI bus.
+ */
+int __ulpi_register_driver(struct ulpi_driver *drv, struct module *module)
+{
+	if (!drv->probe)
+		return -EINVAL;
+
+	drv->driver.owner = module;
+	drv->driver.bus = &ulpi_bus;
+
+	return driver_register(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(__ulpi_register_driver);
+
+/**
+ * ulpi_unregister_driver - unregister a driver with the ULPI bus
+ * @drv: driver to unregister
+ *
+ * Unregisters a driver with the ULPI bus.
+ */
+void ulpi_unregister_driver(struct ulpi_driver *drv)
+{
+	driver_unregister(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(ulpi_unregister_driver);
+
+/* -------------------------------------------------------------------------- */
+
+static int ulpi_of_register(struct ulpi *ulpi)
+{
+	struct device_node *np = NULL, *child;
+	struct device *parent;
+
+	/* Find a ulpi bus underneath the parent or the grandparent */
+	parent = ulpi->dev.parent;
+	if (parent->of_node)
+		np = of_get_child_by_name(parent->of_node, "ulpi");
+	else if (parent->parent && parent->parent->of_node)
+		np = of_get_child_by_name(parent->parent->of_node, "ulpi");
+	if (!np)
+		return 0;
+
+	child = of_get_next_available_child(np, NULL);
+	of_node_put(np);
+	if (!child)
+		return -EINVAL;
+
+	ulpi->dev.of_node = child;
+
+	return 0;
+}
+
+static int ulpi_read_id(struct ulpi *ulpi)
+{
+	int ret;
+
+	/* Test the interface */
+	ret = ulpi_write(ulpi, ULPI_SCRATCH, 0xaa);
+	if (ret < 0)
+		goto err;
+
+	ret = ulpi_read(ulpi, ULPI_SCRATCH);
+	if (ret < 0)
+		return ret;
+
+	if (ret != 0xaa)
+		goto err;
+
+	ulpi->id.vendor = ulpi_read(ulpi, ULPI_VENDOR_ID_LOW);
+	ulpi->id.vendor |= ulpi_read(ulpi, ULPI_VENDOR_ID_HIGH) << 8;
+
+	ulpi->id.product = ulpi_read(ulpi, ULPI_PRODUCT_ID_LOW);
+	ulpi->id.product |= ulpi_read(ulpi, ULPI_PRODUCT_ID_HIGH) << 8;
+
+	/* Some ULPI devices don't have a vendor id so rely on OF match */
+	if (ulpi->id.vendor == 0)
+		goto err;
+
+	request_module("ulpi:v%04xp%04x", ulpi->id.vendor, ulpi->id.product);
+	return 0;
+err:
+	of_request_module(ulpi->dev.of_node);
+	return 0;
+}
+
+static int ulpi_regs_show(struct seq_file *seq, void *data)
+{
+	struct ulpi *ulpi = seq->private;
+
+#define ulpi_print(name, reg) do { \
+	int ret = ulpi_read(ulpi, reg); \
+	if (ret < 0) \
+		return ret; \
+	seq_printf(seq, name " %.02x\n", ret); \
+} while (0)
+
+	ulpi_print("Vendor ID Low               ", ULPI_VENDOR_ID_LOW);
+	ulpi_print("Vendor ID High              ", ULPI_VENDOR_ID_HIGH);
+	ulpi_print("Product ID Low              ", ULPI_PRODUCT_ID_LOW);
+	ulpi_print("Product ID High             ", ULPI_PRODUCT_ID_HIGH);
+	ulpi_print("Function Control            ", ULPI_FUNC_CTRL);
+	ulpi_print("Interface Control           ", ULPI_IFC_CTRL);
+	ulpi_print("OTG Control                 ", ULPI_OTG_CTRL);
+	ulpi_print("USB Interrupt Enable Rising ", ULPI_USB_INT_EN_RISE);
+	ulpi_print("USB Interrupt Enable Falling", ULPI_USB_INT_EN_FALL);
+	ulpi_print("USB Interrupt Status        ", ULPI_USB_INT_STS);
+	ulpi_print("USB Interrupt Latch         ", ULPI_USB_INT_LATCH);
+	ulpi_print("Debug                       ", ULPI_DEBUG);
+	ulpi_print("Scratch Register            ", ULPI_SCRATCH);
+	ulpi_print("Carkit Control              ", ULPI_CARKIT_CTRL);
+	ulpi_print("Carkit Interrupt Delay      ", ULPI_CARKIT_INT_DELAY);
+	ulpi_print("Carkit Interrupt Enable     ", ULPI_CARKIT_INT_EN);
+	ulpi_print("Carkit Interrupt Status     ", ULPI_CARKIT_INT_STS);
+	ulpi_print("Carkit Interrupt Latch      ", ULPI_CARKIT_INT_LATCH);
+	ulpi_print("Carkit Pulse Control        ", ULPI_CARKIT_PLS_CTRL);
+	ulpi_print("Transmit Positive Width     ", ULPI_TX_POS_WIDTH);
+	ulpi_print("Transmit Negative Width     ", ULPI_TX_NEG_WIDTH);
+	ulpi_print("Receive Polarity Recovery   ", ULPI_POLARITY_RECOVERY);
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(ulpi_regs);
+
+static struct dentry *ulpi_root;
+
+static int ulpi_register(struct device *dev, struct ulpi *ulpi)
+{
+	int ret;
+	struct dentry *root;
+
+	ulpi->dev.parent = dev; /* needed early for ops */
+	ulpi->dev.bus = &ulpi_bus;
+	ulpi->dev.type = &ulpi_dev_type;
+
+	device_initialize(&ulpi->dev);
+
+	dev_set_name(&ulpi->dev, "%s.ulpi", dev_name(dev));
+
+	ACPI_COMPANION_SET(&ulpi->dev, ACPI_COMPANION(dev));
+
+	ret = ulpi_of_register(ulpi);
+	if (ret)
+		return ret;
+
+	ret = ulpi_read_id(ulpi);
+	if (ret)
+		return ret;
+
+	ret = device_add(&ulpi->dev);
+	if (ret)
+		return ret;
+
+	root = debugfs_create_dir(dev_name(&ulpi->dev), ulpi_root);
+	debugfs_create_file("regs", 0444, root, ulpi, &ulpi_regs_fops);
+
+	dev_dbg(&ulpi->dev, "registered ULPI PHY: vendor %04x, product %04x\n",
+		ulpi->id.vendor, ulpi->id.product);
+
+	return 0;
+}
+
+/**
+ * ulpi_register_interface - instantiate new ULPI device
+ * @dev: USB controller's device interface
+ * @ops: ULPI register access
+ *
+ * Allocates and registers a ULPI device and an interface for it. Called from
+ * the USB controller that provides the ULPI interface.
+ */
+struct ulpi *ulpi_register_interface(struct device *dev,
+				     const struct ulpi_ops *ops)
+{
+	struct ulpi *ulpi;
+	int ret;
+
+	ulpi = kzalloc_obj(*ulpi);
+	if (!ulpi)
+		return ERR_PTR(-ENOMEM);
+
+	ulpi->ops = ops;
+
+	ret = ulpi_register(dev, ulpi);
+	if (ret) {
+		put_device(&ulpi->dev);
+		return ERR_PTR(ret);
+	}
+
+	return ulpi;
+}
+EXPORT_SYMBOL_GPL(ulpi_register_interface);
+
+/**
+ * ulpi_unregister_interface - unregister ULPI interface
+ * @ulpi: struct ulpi_interface
+ *
+ * Unregisters a ULPI device and it's interface that was created with
+ * ulpi_create_interface().
+ */
+void ulpi_unregister_interface(struct ulpi *ulpi)
+{
+	debugfs_lookup_and_remove(dev_name(&ulpi->dev), ulpi_root);
+	device_unregister(&ulpi->dev);
+}
+EXPORT_SYMBOL_GPL(ulpi_unregister_interface);
+
+/* -------------------------------------------------------------------------- */
+
+static int __init ulpi_init(void)
+{
+	int ret;
+
+	ulpi_root = debugfs_create_dir(KBUILD_MODNAME, NULL);
+	ret = bus_register(&ulpi_bus);
+	if (ret)
+		debugfs_remove(ulpi_root);
+	return ret;
+}
+subsys_initcall(ulpi_init);
+
+static void __exit ulpi_exit(void)
+{
+	bus_unregister(&ulpi_bus);
+	debugfs_remove(ulpi_root);
+}
+module_exit(ulpi_exit);
+
+MODULE_AUTHOR("Intel Corporation");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("USB ULPI PHY bus");