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, 372 insertions, 0 deletions

diff --git a/drivers/clk/clk-fixed-factor.c b/drivers/clk/clk-fixed-factor.c
new file mode 100644
index 000000000..ae473e0af
--- /dev/null
+++ b/drivers/clk/clk-fixed-factor.c
@@ -0,0 +1,372 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2011 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
+ */
+#include <linux/module.h>
+#include <linux/clk-provider.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+
+/*
+ * DOC: basic fixed multiplier and divider clock that cannot gate
+ *
+ * Traits of this clock:
+ * prepare - clk_prepare only ensures that parents are prepared
+ * enable - clk_enable only ensures that parents are enabled
+ * rate - rate is fixed.  clk->rate = parent->rate / div * mult
+ * parent - fixed parent.  No clk_set_parent support
+ */
+
+static unsigned long clk_factor_recalc_rate(struct clk_hw *hw,
+		unsigned long parent_rate)
+{
+	struct clk_fixed_factor *fix = to_clk_fixed_factor(hw);
+	unsigned long long int rate;
+
+	rate = (unsigned long long int)parent_rate * fix->mult;
+	do_div(rate, fix->div);
+	return (unsigned long)rate;
+}
+
+static int clk_factor_determine_rate(struct clk_hw *hw,
+				     struct clk_rate_request *req)
+{
+	struct clk_fixed_factor *fix = to_clk_fixed_factor(hw);
+
+	if (clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT) {
+		struct clk_hw *parent_hw = clk_hw_get_parent(hw);
+		unsigned long best_parent;
+
+		if (!parent_hw)
+			return -EINVAL;
+
+		best_parent = (req->rate / fix->mult) * fix->div;
+		req->best_parent_rate = clk_hw_round_rate(parent_hw, best_parent);
+	}
+
+	req->rate = (req->best_parent_rate / fix->div) * fix->mult;
+
+	return 0;
+}
+
+static int clk_factor_set_rate(struct clk_hw *hw, unsigned long rate,
+				unsigned long parent_rate)
+{
+	/*
+	 * We must report success but we can do so unconditionally because
+	 * clk_factor_determine_rate returns values that ensure this call is a
+	 * nop.
+	 */
+
+	return 0;
+}
+
+static unsigned long clk_factor_recalc_accuracy(struct clk_hw *hw,
+						unsigned long parent_accuracy)
+{
+	struct clk_fixed_factor *fix = to_clk_fixed_factor(hw);
+
+	if (fix->flags & CLK_FIXED_FACTOR_FIXED_ACCURACY)
+		return fix->acc;
+
+	return parent_accuracy;
+}
+
+const struct clk_ops clk_fixed_factor_ops = {
+	.determine_rate = clk_factor_determine_rate,
+	.set_rate = clk_factor_set_rate,
+	.recalc_rate = clk_factor_recalc_rate,
+	.recalc_accuracy = clk_factor_recalc_accuracy,
+};
+EXPORT_SYMBOL_GPL(clk_fixed_factor_ops);
+
+static void devm_clk_hw_register_fixed_factor_release(struct device *dev, void *res)
+{
+	struct clk_fixed_factor *fix = res;
+
+	/*
+	 * We can not use clk_hw_unregister_fixed_factor, since it will kfree()
+	 * the hw, resulting in double free. Just unregister the hw and let
+	 * devres code kfree() it.
+	 */
+	clk_hw_unregister(&fix->hw);
+}
+
+struct clk_hw *
+__clk_hw_register_fixed_factor(struct device *dev, struct device_node *np,
+		const char *name, const char *parent_name,
+		const struct clk_hw *parent_hw, const struct clk_parent_data *pdata,
+		unsigned long flags, unsigned int mult, unsigned int div,
+		unsigned long acc, unsigned int fixflags, bool devm)
+{
+	struct clk_fixed_factor *fix;
+	struct clk_init_data init = { };
+	struct clk_hw *hw;
+	int ret;
+
+	/* You can't use devm without a dev */
+	if (devm && !dev)
+		return ERR_PTR(-EINVAL);
+
+	if (devm)
+		fix = devres_alloc(devm_clk_hw_register_fixed_factor_release,
+				sizeof(*fix), GFP_KERNEL);
+	else
+		fix = kmalloc_obj(*fix);
+	if (!fix)
+		return ERR_PTR(-ENOMEM);
+
+	/* struct clk_fixed_factor assignments */
+	fix->mult = mult;
+	fix->div = div;
+	fix->hw.init = &init;
+	fix->acc = acc;
+	fix->flags = fixflags;
+
+	init.name = name;
+	init.ops = &clk_fixed_factor_ops;
+	init.flags = flags;
+	init.parent_names = parent_name ? &parent_name : NULL;
+	init.parent_hws = parent_hw ? &parent_hw : NULL;
+	init.parent_data = pdata;
+	if (parent_name || parent_hw || pdata)
+		init.num_parents = 1;
+	else
+		init.num_parents = 0;
+
+	hw = &fix->hw;
+	if (dev)
+		ret = clk_hw_register(dev, hw);
+	else
+		ret = of_clk_hw_register(np, hw);
+	if (ret) {
+		if (devm)
+			devres_free(fix);
+		else
+			kfree(fix);
+		hw = ERR_PTR(ret);
+	} else if (devm)
+		devres_add(dev, fix);
+
+	return hw;
+}
+EXPORT_SYMBOL_GPL(__clk_hw_register_fixed_factor);
+
+/**
+ * devm_clk_hw_register_fixed_factor_index - Register a fixed factor clock with
+ * parent from DT index
+ * @dev: device that is registering this clock
+ * @name: name of this clock
+ * @index: index of phandle in @dev 'clocks' property
+ * @flags: fixed factor flags
+ * @mult: multiplier
+ * @div: divider
+ *
+ * Return: Pointer to fixed factor clk_hw structure that was registered or
+ * an error pointer.
+ */
+struct clk_hw *devm_clk_hw_register_fixed_factor_index(struct device *dev,
+		const char *name, unsigned int index, unsigned long flags,
+		unsigned int mult, unsigned int div)
+{
+	const struct clk_parent_data pdata = { .index = index };
+
+	return __clk_hw_register_fixed_factor(dev, NULL, name, NULL, NULL, &pdata,
+					      flags, mult, div, 0, 0, true);
+}
+EXPORT_SYMBOL_GPL(devm_clk_hw_register_fixed_factor_index);
+
+struct clk_hw *clk_hw_register_fixed_factor_fwname(struct device *dev,
+		struct device_node *np, const char *name, const char *fw_name,
+		unsigned long flags, unsigned int mult, unsigned int div)
+{
+	const struct clk_parent_data pdata = { .index = -1, .fw_name = fw_name };
+
+	return __clk_hw_register_fixed_factor(dev, np, name, NULL, NULL,
+			&pdata, flags, mult, div, 0, 0, false);
+}
+EXPORT_SYMBOL_GPL(clk_hw_register_fixed_factor_fwname);
+
+struct clk_hw *clk_hw_register_fixed_factor_with_accuracy_fwname(struct device *dev,
+		struct device_node *np, const char *name, const char *fw_name,
+		unsigned long flags, unsigned int mult, unsigned int div,
+		unsigned long acc)
+{
+	const struct clk_parent_data pdata = { .index = -1, .fw_name = fw_name };
+
+	return __clk_hw_register_fixed_factor(dev, np, name, NULL, NULL,
+			&pdata, flags, mult, div, acc,
+			CLK_FIXED_FACTOR_FIXED_ACCURACY, false);
+}
+EXPORT_SYMBOL_GPL(clk_hw_register_fixed_factor_with_accuracy_fwname);
+
+struct clk_hw *clk_hw_register_fixed_factor_index(struct device *dev,
+		const char *name, unsigned int index, unsigned long flags,
+		unsigned int mult, unsigned int div)
+{
+	const struct clk_parent_data pdata = { .index = index };
+
+	return __clk_hw_register_fixed_factor(dev, NULL, name, NULL, NULL, &pdata,
+					      flags, mult, div, 0, 0, false);
+}
+EXPORT_SYMBOL_GPL(clk_hw_register_fixed_factor_index);
+
+struct clk *clk_register_fixed_factor(struct device *dev, const char *name,
+		const char *parent_name, unsigned long flags,
+		unsigned int mult, unsigned int div)
+{
+	struct clk_hw *hw;
+
+	hw = clk_hw_register_fixed_factor(dev, name, parent_name, flags, mult,
+					  div);
+	if (IS_ERR(hw))
+		return ERR_CAST(hw);
+	return hw->clk;
+}
+EXPORT_SYMBOL_GPL(clk_register_fixed_factor);
+
+void clk_unregister_fixed_factor(struct clk *clk)
+{
+	struct clk_hw *hw;
+
+	hw = __clk_get_hw(clk);
+	if (!hw)
+		return;
+
+	clk_unregister(clk);
+	kfree(to_clk_fixed_factor(hw));
+}
+EXPORT_SYMBOL_GPL(clk_unregister_fixed_factor);
+
+void clk_hw_unregister_fixed_factor(struct clk_hw *hw)
+{
+	struct clk_fixed_factor *fix;
+
+	fix = to_clk_fixed_factor(hw);
+
+	clk_hw_unregister(hw);
+	kfree(fix);
+}
+EXPORT_SYMBOL_GPL(clk_hw_unregister_fixed_factor);
+
+struct clk_hw *devm_clk_hw_register_fixed_factor_fwname(struct device *dev,
+		struct device_node *np, const char *name, const char *fw_name,
+		unsigned long flags, unsigned int mult, unsigned int div)
+{
+	const struct clk_parent_data pdata = { .index = -1, .fw_name = fw_name };
+
+	return __clk_hw_register_fixed_factor(dev, np, name, NULL, NULL,
+			&pdata, flags, mult, div, 0, 0, true);
+}
+EXPORT_SYMBOL_GPL(devm_clk_hw_register_fixed_factor_fwname);
+
+struct clk_hw *devm_clk_hw_register_fixed_factor_with_accuracy_fwname(struct device *dev,
+		struct device_node *np, const char *name, const char *fw_name,
+		unsigned long flags, unsigned int mult, unsigned int div,
+		unsigned long acc)
+{
+	const struct clk_parent_data pdata = { .index = -1, .fw_name = fw_name };
+
+	return __clk_hw_register_fixed_factor(dev, np, name, NULL, NULL,
+			&pdata, flags, mult, div, acc,
+			CLK_FIXED_FACTOR_FIXED_ACCURACY, true);
+}
+EXPORT_SYMBOL_GPL(devm_clk_hw_register_fixed_factor_with_accuracy_fwname);
+
+#ifdef CONFIG_OF
+static struct clk_hw *_of_fixed_factor_clk_setup(struct device_node *node)
+{
+	struct clk_hw *hw;
+	const char *clk_name = node->name;
+	const struct clk_parent_data pdata = { .index = 0 };
+	u32 div, mult;
+	int ret;
+
+	if (of_property_read_u32(node, "clock-div", &div)) {
+		pr_err("%s Fixed factor clock <%pOFn> must have a clock-div property\n",
+			__func__, node);
+		return ERR_PTR(-EIO);
+	}
+
+	if (of_property_read_u32(node, "clock-mult", &mult)) {
+		pr_err("%s Fixed factor clock <%pOFn> must have a clock-mult property\n",
+			__func__, node);
+		return ERR_PTR(-EIO);
+	}
+
+	of_property_read_string(node, "clock-output-names", &clk_name);
+
+	hw = __clk_hw_register_fixed_factor(NULL, node, clk_name, NULL, NULL,
+					    &pdata, 0, mult, div, 0, 0, false);
+	if (IS_ERR(hw)) {
+		/*
+		 * Clear OF_POPULATED flag so that clock registration can be
+		 * attempted again from probe function.
+		 */
+		of_node_clear_flag(node, OF_POPULATED);
+		return ERR_CAST(hw);
+	}
+
+	ret = of_clk_add_hw_provider(node, of_clk_hw_simple_get, hw);
+	if (ret) {
+		clk_hw_unregister_fixed_factor(hw);
+		return ERR_PTR(ret);
+	}
+
+	return hw;
+}
+
+/**
+ * of_fixed_factor_clk_setup() - Setup function for simple fixed factor clock
+ * @node:	device node for the clock
+ */
+void __init of_fixed_factor_clk_setup(struct device_node *node)
+{
+	_of_fixed_factor_clk_setup(node);
+}
+CLK_OF_DECLARE(fixed_factor_clk, "fixed-factor-clock",
+		of_fixed_factor_clk_setup);
+
+static void of_fixed_factor_clk_remove(struct platform_device *pdev)
+{
+	struct clk_hw *clk = platform_get_drvdata(pdev);
+
+	of_clk_del_provider(pdev->dev.of_node);
+	clk_hw_unregister_fixed_factor(clk);
+}
+
+static int of_fixed_factor_clk_probe(struct platform_device *pdev)
+{
+	struct clk_hw *clk;
+
+	/*
+	 * This function is not executed when of_fixed_factor_clk_setup
+	 * succeeded.
+	 */
+	clk = _of_fixed_factor_clk_setup(pdev->dev.of_node);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	platform_set_drvdata(pdev, clk);
+
+	return 0;
+}
+
+static const struct of_device_id of_fixed_factor_clk_ids[] = {
+	{ .compatible = "fixed-factor-clock" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, of_fixed_factor_clk_ids);
+
+static struct platform_driver of_fixed_factor_clk_driver = {
+	.driver = {
+		.name = "of_fixed_factor_clk",
+		.of_match_table = of_fixed_factor_clk_ids,
+	},
+	.probe = of_fixed_factor_clk_probe,
+	.remove = of_fixed_factor_clk_remove,
+};
+builtin_platform_driver(of_fixed_factor_clk_driver);
+#endif