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, 556 insertions, 0 deletions

diff --git a/drivers/clk/davinci/psc.c b/drivers/clk/davinci/psc.c
new file mode 100644
index 000000000..ff603520d
--- /dev/null
+++ b/drivers/clk/davinci/psc.c
@@ -0,0 +1,556 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Clock driver for TI Davinci PSC controllers
+ *
+ * Copyright (C) 2017 David Lechner <david@lechnology.com>
+ *
+ * Based on: drivers/clk/keystone/gate.c
+ * Copyright (C) 2013 Texas Instruments.
+ *	Murali Karicheri <m-karicheri2@ti.com>
+ *	Santosh Shilimkar <santosh.shilimkar@ti.com>
+ *
+ * And: arch/arm/mach-davinci/psc.c
+ * Copyright (C) 2006 Texas Instruments.
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clk.h>
+#include <linux/clk/davinci.h>
+#include <linux/clkdev.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/pm_clock.h>
+#include <linux/pm_domain.h>
+#include <linux/regmap.h>
+#include <linux/reset-controller.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#include "psc.h"
+
+/* PSC register offsets */
+#define EPCPR			0x070
+#define PTCMD			0x120
+#define PTSTAT			0x128
+#define PDSTAT(n)		(0x200 + 4 * (n))
+#define PDCTL(n)		(0x300 + 4 * (n))
+#define MDSTAT(n)		(0x800 + 4 * (n))
+#define MDCTL(n)		(0xa00 + 4 * (n))
+
+/* PSC module states */
+enum davinci_lpsc_state {
+	LPSC_STATE_SWRSTDISABLE	= 0,
+	LPSC_STATE_SYNCRST	= 1,
+	LPSC_STATE_DISABLE	= 2,
+	LPSC_STATE_ENABLE	= 3,
+};
+
+#define MDSTAT_STATE_MASK	GENMASK(5, 0)
+#define MDSTAT_MCKOUT		BIT(12)
+#define PDSTAT_STATE_MASK	GENMASK(4, 0)
+#define MDCTL_FORCE		BIT(31)
+#define MDCTL_LRESET		BIT(8)
+#define PDCTL_EPCGOOD		BIT(8)
+#define PDCTL_NEXT		BIT(0)
+
+struct davinci_psc_data {
+	struct clk_onecell_data clk_data;
+	struct genpd_onecell_data pm_data;
+	struct reset_controller_dev rcdev;
+};
+
+/**
+ * struct davinci_lpsc_clk - LPSC clock structure
+ * @dev: the device that provides this LPSC or NULL
+ * @hw: clk_hw for the LPSC
+ * @pm_domain: power domain for the LPSC
+ * @genpd_clk: clock reference owned by @pm_domain
+ * @regmap: PSC MMIO region
+ * @md: Module domain (LPSC module id)
+ * @pd: Power domain
+ * @flags: LPSC_* quirk flags
+ */
+struct davinci_lpsc_clk {
+	struct device *dev;
+	struct clk_hw hw;
+	struct generic_pm_domain pm_domain;
+	struct clk *genpd_clk;
+	struct regmap *regmap;
+	u32 md;
+	u32 pd;
+	u32 flags;
+};
+
+#define to_davinci_psc_data(x) container_of(x, struct davinci_psc_data, x)
+#define to_davinci_lpsc_clk(x) container_of(x, struct davinci_lpsc_clk, x)
+
+/**
+ * best_dev_name - get the "best" device name.
+ * @dev: the device
+ *
+ * Returns the device tree compatible name if the device has a DT node,
+ * otherwise return the device name. This is mainly needed because clkdev
+ * lookups are limited to 20 chars for dev_id and when using device tree,
+ * dev_name(dev) is much longer than that.
+ */
+static inline const char *best_dev_name(struct device *dev)
+{
+	const char *compatible;
+
+	if (!of_property_read_string(dev->of_node, "compatible", &compatible))
+		return compatible;
+
+	return dev_name(dev);
+}
+
+static void davinci_lpsc_config(struct davinci_lpsc_clk *lpsc,
+				enum davinci_lpsc_state next_state)
+{
+	u32 epcpr, pdstat, mdstat, ptstat;
+
+	regmap_write_bits(lpsc->regmap, MDCTL(lpsc->md), MDSTAT_STATE_MASK,
+			  next_state);
+
+	if (lpsc->flags & LPSC_FORCE)
+		regmap_write_bits(lpsc->regmap, MDCTL(lpsc->md), MDCTL_FORCE,
+				  MDCTL_FORCE);
+
+	regmap_read(lpsc->regmap, PDSTAT(lpsc->pd), &pdstat);
+	if ((pdstat & PDSTAT_STATE_MASK) == 0) {
+		regmap_write_bits(lpsc->regmap, PDCTL(lpsc->pd), PDCTL_NEXT,
+				  PDCTL_NEXT);
+
+		regmap_write(lpsc->regmap, PTCMD, BIT(lpsc->pd));
+
+		regmap_read_poll_timeout(lpsc->regmap, EPCPR, epcpr,
+					 epcpr & BIT(lpsc->pd), 0, 0);
+
+		regmap_write_bits(lpsc->regmap, PDCTL(lpsc->pd), PDCTL_EPCGOOD,
+				  PDCTL_EPCGOOD);
+	} else {
+		regmap_write(lpsc->regmap, PTCMD, BIT(lpsc->pd));
+	}
+
+	regmap_read_poll_timeout(lpsc->regmap, PTSTAT, ptstat,
+				 !(ptstat & BIT(lpsc->pd)), 0, 0);
+
+	regmap_read_poll_timeout(lpsc->regmap, MDSTAT(lpsc->md), mdstat,
+				 (mdstat & MDSTAT_STATE_MASK) == next_state,
+				 0, 0);
+}
+
+static int davinci_lpsc_clk_enable(struct clk_hw *hw)
+{
+	struct davinci_lpsc_clk *lpsc = to_davinci_lpsc_clk(hw);
+
+	davinci_lpsc_config(lpsc, LPSC_STATE_ENABLE);
+
+	return 0;
+}
+
+static void davinci_lpsc_clk_disable(struct clk_hw *hw)
+{
+	struct davinci_lpsc_clk *lpsc = to_davinci_lpsc_clk(hw);
+
+	davinci_lpsc_config(lpsc, LPSC_STATE_DISABLE);
+}
+
+static int davinci_lpsc_clk_is_enabled(struct clk_hw *hw)
+{
+	struct davinci_lpsc_clk *lpsc = to_davinci_lpsc_clk(hw);
+	u32 mdstat;
+
+	regmap_read(lpsc->regmap, MDSTAT(lpsc->md), &mdstat);
+
+	return (mdstat & MDSTAT_MCKOUT) ? 1 : 0;
+}
+
+static const struct clk_ops davinci_lpsc_clk_ops = {
+	.enable		= davinci_lpsc_clk_enable,
+	.disable	= davinci_lpsc_clk_disable,
+	.is_enabled	= davinci_lpsc_clk_is_enabled,
+};
+
+static int davinci_psc_genpd_attach_dev(struct generic_pm_domain *pm_domain,
+					struct device *dev)
+{
+	struct davinci_lpsc_clk *lpsc = to_davinci_lpsc_clk(pm_domain);
+	struct clk *clk;
+	int ret;
+
+	/*
+	 * pm_clk_remove_clk() will call clk_put(), so we have to use clk_get()
+	 * to get the clock instead of using lpsc->hw.clk directly.
+	 */
+	clk = clk_get_sys(best_dev_name(lpsc->dev), clk_hw_get_name(&lpsc->hw));
+	if (IS_ERR(clk))
+		return (PTR_ERR(clk));
+
+	ret = pm_clk_create(dev);
+	if (ret < 0)
+		goto fail_clk_put;
+
+	ret = pm_clk_add_clk(dev, clk);
+	if (ret < 0)
+		goto fail_pm_clk_destroy;
+
+	lpsc->genpd_clk = clk;
+
+	return 0;
+
+fail_pm_clk_destroy:
+	pm_clk_destroy(dev);
+fail_clk_put:
+	clk_put(clk);
+
+	return ret;
+}
+
+static void davinci_psc_genpd_detach_dev(struct generic_pm_domain *pm_domain,
+					 struct device *dev)
+{
+	struct davinci_lpsc_clk *lpsc = to_davinci_lpsc_clk(pm_domain);
+
+	pm_clk_remove_clk(dev, lpsc->genpd_clk);
+	pm_clk_destroy(dev);
+
+	lpsc->genpd_clk = NULL;
+}
+
+/**
+ * davinci_lpsc_clk_register - register LPSC clock
+ * @dev: the clocks's device or NULL
+ * @name: name of this clock
+ * @parent_name: name of clock's parent
+ * @regmap: PSC MMIO region
+ * @md: local PSC number
+ * @pd: power domain
+ * @flags: LPSC_* flags
+ */
+static struct davinci_lpsc_clk *
+davinci_lpsc_clk_register(struct device *dev, const char *name,
+			  const char *parent_name, struct regmap *regmap,
+			  u32 md, u32 pd, u32 flags)
+{
+	struct clk_init_data init;
+	struct davinci_lpsc_clk *lpsc;
+	int ret;
+	bool is_on;
+
+	lpsc = kzalloc_obj(*lpsc);
+	if (!lpsc)
+		return ERR_PTR(-ENOMEM);
+
+	init.name = name;
+	init.ops = &davinci_lpsc_clk_ops;
+	init.parent_names = (parent_name ? &parent_name : NULL);
+	init.num_parents = (parent_name ? 1 : 0);
+	init.flags = 0;
+
+	if (flags & LPSC_ALWAYS_ENABLED)
+		init.flags |= CLK_IS_CRITICAL;
+
+	if (flags & LPSC_SET_RATE_PARENT)
+		init.flags |= CLK_SET_RATE_PARENT;
+
+	lpsc->dev = dev;
+	lpsc->regmap = regmap;
+	lpsc->hw.init = &init;
+	lpsc->md = md;
+	lpsc->pd = pd;
+	lpsc->flags = flags;
+
+	ret = clk_hw_register(dev, &lpsc->hw);
+	if (ret < 0) {
+		kfree(lpsc);
+		return ERR_PTR(ret);
+	}
+
+	/* for now, genpd is only registered when using device-tree */
+	if (!dev || !dev->of_node)
+		return lpsc;
+
+	/* genpd attach needs a way to look up this clock */
+	ret = clk_hw_register_clkdev(&lpsc->hw, name, best_dev_name(dev));
+
+	lpsc->pm_domain.name = devm_kasprintf(dev, GFP_KERNEL, "%s: %s",
+					      best_dev_name(dev), name);
+	if (!lpsc->pm_domain.name) {
+		clk_hw_unregister(&lpsc->hw);
+		kfree(lpsc);
+		return ERR_PTR(-ENOMEM);
+	}
+	lpsc->pm_domain.attach_dev = davinci_psc_genpd_attach_dev;
+	lpsc->pm_domain.detach_dev = davinci_psc_genpd_detach_dev;
+	lpsc->pm_domain.flags = GENPD_FLAG_PM_CLK;
+
+	is_on = davinci_lpsc_clk_is_enabled(&lpsc->hw);
+	pm_genpd_init(&lpsc->pm_domain, NULL, is_on);
+
+	return lpsc;
+}
+
+static int davinci_lpsc_clk_reset(struct clk *clk, bool reset)
+{
+	struct clk_hw *hw = __clk_get_hw(clk);
+	struct davinci_lpsc_clk *lpsc = to_davinci_lpsc_clk(hw);
+	u32 mdctl;
+
+	if (IS_ERR_OR_NULL(lpsc))
+		return -EINVAL;
+
+	mdctl = reset ? 0 : MDCTL_LRESET;
+	regmap_write_bits(lpsc->regmap, MDCTL(lpsc->md), MDCTL_LRESET, mdctl);
+
+	return 0;
+}
+
+static int davinci_psc_reset_assert(struct reset_controller_dev *rcdev,
+				    unsigned long id)
+{
+	struct davinci_psc_data *psc = to_davinci_psc_data(rcdev);
+	struct clk *clk = psc->clk_data.clks[id];
+
+	return davinci_lpsc_clk_reset(clk, true);
+}
+
+static int davinci_psc_reset_deassert(struct reset_controller_dev *rcdev,
+				      unsigned long id)
+{
+	struct davinci_psc_data *psc = to_davinci_psc_data(rcdev);
+	struct clk *clk = psc->clk_data.clks[id];
+
+	return davinci_lpsc_clk_reset(clk, false);
+}
+
+static const struct reset_control_ops davinci_psc_reset_ops = {
+	.assert		= davinci_psc_reset_assert,
+	.deassert	= davinci_psc_reset_deassert,
+};
+
+static int davinci_psc_reset_of_xlate(struct reset_controller_dev *rcdev,
+				      const struct of_phandle_args *reset_spec)
+{
+	struct of_phandle_args clkspec = *reset_spec; /* discard const qualifier */
+	struct clk *clk;
+	struct clk_hw *hw;
+	struct davinci_lpsc_clk *lpsc;
+
+	/* the clock node is the same as the reset node */
+	clk = of_clk_get_from_provider(&clkspec);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	hw = __clk_get_hw(clk);
+	lpsc = to_davinci_lpsc_clk(hw);
+	clk_put(clk);
+
+	/* not all modules support local reset */
+	if (!(lpsc->flags & LPSC_LOCAL_RESET))
+		return -EINVAL;
+
+	return lpsc->md;
+}
+
+static const struct regmap_config davinci_psc_regmap_config = {
+	.reg_bits	= 32,
+	.reg_stride	= 4,
+	.val_bits	= 32,
+};
+
+static struct davinci_psc_data *
+__davinci_psc_register_clocks(struct device *dev,
+			      const struct davinci_lpsc_clk_info *info,
+			      int num_clks,
+			      void __iomem *base)
+{
+	struct davinci_psc_data *psc;
+	struct clk **clks;
+	struct generic_pm_domain **pm_domains;
+	struct regmap *regmap;
+	int i, ret;
+
+	psc = kzalloc_obj(*psc);
+	if (!psc)
+		return ERR_PTR(-ENOMEM);
+
+	clks = kmalloc_objs(*clks, num_clks);
+	if (!clks) {
+		ret = -ENOMEM;
+		goto err_free_psc;
+	}
+
+	psc->clk_data.clks = clks;
+	psc->clk_data.clk_num = num_clks;
+
+	/*
+	 * init array with error so that of_clk_src_onecell_get() doesn't
+	 * return NULL for gaps in the sparse array
+	 */
+	for (i = 0; i < num_clks; i++)
+		clks[i] = ERR_PTR(-ENOENT);
+
+	pm_domains = kzalloc_objs(*pm_domains, num_clks);
+	if (!pm_domains) {
+		ret = -ENOMEM;
+		goto err_free_clks;
+	}
+
+	psc->pm_data.domains = pm_domains;
+	psc->pm_data.num_domains = num_clks;
+
+	regmap = regmap_init_mmio(dev, base, &davinci_psc_regmap_config);
+	if (IS_ERR(regmap)) {
+		ret = PTR_ERR(regmap);
+		goto err_free_pm_domains;
+	}
+
+	for (; info->name; info++) {
+		struct davinci_lpsc_clk *lpsc;
+
+		lpsc = davinci_lpsc_clk_register(dev, info->name, info->parent,
+						 regmap, info->md, info->pd,
+						 info->flags);
+		if (IS_ERR(lpsc)) {
+			dev_warn(dev, "Failed to register %s (%ld)\n",
+				 info->name, PTR_ERR(lpsc));
+			continue;
+		}
+
+		clks[info->md] = lpsc->hw.clk;
+		pm_domains[info->md] = &lpsc->pm_domain;
+	}
+
+	/*
+	 * for now, a reset controller is only registered when there is a device
+	 * to associate it with.
+	 */
+	if (!dev)
+		return psc;
+
+	psc->rcdev.ops = &davinci_psc_reset_ops;
+	psc->rcdev.owner = THIS_MODULE;
+	psc->rcdev.dev = dev;
+	psc->rcdev.of_node = dev->of_node;
+	psc->rcdev.of_reset_n_cells = 1;
+	psc->rcdev.of_xlate = davinci_psc_reset_of_xlate;
+	psc->rcdev.nr_resets = num_clks;
+
+	ret = devm_reset_controller_register(dev, &psc->rcdev);
+	if (ret < 0)
+		dev_warn(dev, "Failed to register reset controller (%d)\n", ret);
+
+	return psc;
+
+err_free_pm_domains:
+	kfree(pm_domains);
+err_free_clks:
+	kfree(clks);
+err_free_psc:
+	kfree(psc);
+
+	return ERR_PTR(ret);
+}
+
+int davinci_psc_register_clocks(struct device *dev,
+				const struct davinci_lpsc_clk_info *info,
+				u8 num_clks,
+				void __iomem *base)
+{
+	struct davinci_psc_data *psc;
+
+	psc = __davinci_psc_register_clocks(dev, info, num_clks, base);
+	if (IS_ERR(psc))
+		return PTR_ERR(psc);
+
+	for (; info->name; info++) {
+		const struct davinci_lpsc_clkdev_info *cdevs = info->cdevs;
+		struct clk *clk = psc->clk_data.clks[info->md];
+
+		if (!cdevs || IS_ERR_OR_NULL(clk))
+			continue;
+
+		for (; cdevs->con_id || cdevs->dev_id; cdevs++)
+			clk_register_clkdev(clk, cdevs->con_id, cdevs->dev_id);
+	}
+
+	return 0;
+}
+
+int of_davinci_psc_clk_init(struct device *dev,
+			    const struct davinci_lpsc_clk_info *info,
+			    u8 num_clks,
+			    void __iomem *base)
+{
+	struct device_node *node = dev->of_node;
+	struct davinci_psc_data *psc;
+
+	psc = __davinci_psc_register_clocks(dev, info, num_clks, base);
+	if (IS_ERR(psc))
+		return PTR_ERR(psc);
+
+	of_genpd_add_provider_onecell(node, &psc->pm_data);
+
+	of_clk_add_provider(node, of_clk_src_onecell_get, &psc->clk_data);
+
+	return 0;
+}
+
+static const struct of_device_id davinci_psc_of_match[] = {
+	{ .compatible = "ti,da850-psc0", .data = &of_da850_psc0_init_data },
+	{ .compatible = "ti,da850-psc1", .data = &of_da850_psc1_init_data },
+	{ }
+};
+
+static const struct platform_device_id davinci_psc_id_table[] = {
+	{ .name = "da850-psc0", .driver_data = (kernel_ulong_t)&da850_psc0_init_data },
+	{ .name = "da850-psc1", .driver_data = (kernel_ulong_t)&da850_psc1_init_data },
+	{ }
+};
+
+static int davinci_psc_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	const struct davinci_psc_init_data *init_data = NULL;
+	void __iomem *base;
+	int ret;
+
+	init_data = device_get_match_data(dev);
+	if (!init_data && pdev->id_entry)
+		init_data = (void *)pdev->id_entry->driver_data;
+
+	if (!init_data) {
+		dev_err(dev, "unable to find driver init data\n");
+		return -EINVAL;
+	}
+
+	base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	ret = devm_clk_bulk_get(dev, init_data->num_parent_clks,
+				init_data->parent_clks);
+	if (ret < 0)
+		return ret;
+
+	return init_data->psc_init(dev, base);
+}
+
+static struct platform_driver davinci_psc_driver = {
+	.probe		= davinci_psc_probe,
+	.driver		= {
+		.name		= "davinci-psc-clk",
+		.of_match_table	= davinci_psc_of_match,
+	},
+	.id_table	= davinci_psc_id_table,
+};
+
+static int __init davinci_psc_driver_init(void)
+{
+	return platform_driver_register(&davinci_psc_driver);
+}
+
+/* has to be postcore_initcall because davinci_gpio depend on PSC clocks */
+postcore_initcall(davinci_psc_driver_init);