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, 545 insertions, 0 deletions

diff --git a/drivers/clocksource/ingenic-sysost.c b/drivers/clocksource/ingenic-sysost.c
new file mode 100644
index 000000000..026615bbe
--- /dev/null
+++ b/drivers/clocksource/ingenic-sysost.c
@@ -0,0 +1,545 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Ingenic XBurst SoCs SYSOST clocks driver
+ * Copyright (c) 2020 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/interrupt.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+#include <linux/slab.h>
+#include <linux/syscore_ops.h>
+
+#include <dt-bindings/clock/ingenic,sysost.h>
+
+/* OST register offsets */
+#define OST_REG_OSTCCR			0x00
+#define OST_REG_OSTCR			0x08
+#define OST_REG_OSTFR			0x0c
+#define OST_REG_OSTMR			0x10
+#define OST_REG_OST1DFR			0x14
+#define OST_REG_OST1CNT			0x18
+#define OST_REG_OST2CNTL		0x20
+#define OST_REG_OSTCNT2HBUF		0x24
+#define OST_REG_OSTESR			0x34
+#define OST_REG_OSTECR			0x38
+
+/* bits within the OSTCCR register */
+#define OSTCCR_PRESCALE1_MASK	0x3
+#define OSTCCR_PRESCALE2_MASK	0xc
+
+/* bits within the OSTCR register */
+#define OSTCR_OST1CLR			BIT(0)
+#define OSTCR_OST2CLR			BIT(1)
+
+/* bits within the OSTFR register */
+#define OSTFR_FFLAG				BIT(0)
+
+/* bits within the OSTMR register */
+#define OSTMR_FMASK				BIT(0)
+
+/* bits within the OSTESR register */
+#define OSTESR_OST1ENS			BIT(0)
+#define OSTESR_OST2ENS			BIT(1)
+
+/* bits within the OSTECR register */
+#define OSTECR_OST1ENC			BIT(0)
+#define OSTECR_OST2ENC			BIT(1)
+
+struct ingenic_soc_info {
+	unsigned int num_channels;
+};
+
+struct ingenic_ost_clk_info {
+	struct clk_init_data init_data;
+	u8 ostccr_reg;
+};
+
+struct ingenic_ost_clk {
+	struct clk_hw hw;
+	unsigned int idx;
+	struct ingenic_ost *ost;
+	const struct ingenic_ost_clk_info *info;
+};
+
+struct ingenic_ost {
+	void __iomem *base;
+	const struct ingenic_soc_info *soc_info;
+	struct clk *clk, *percpu_timer_clk, *global_timer_clk;
+	struct clock_event_device cevt;
+	struct clocksource cs;
+	char name[20];
+
+	struct clk_hw_onecell_data *clocks;
+};
+
+static struct ingenic_ost *ingenic_ost;
+
+static inline struct ingenic_ost_clk *to_ost_clk(struct clk_hw *hw)
+{
+	return container_of(hw, struct ingenic_ost_clk, hw);
+}
+
+static unsigned long ingenic_ost_percpu_timer_recalc_rate(struct clk_hw *hw,
+		unsigned long parent_rate)
+{
+	struct ingenic_ost_clk *ost_clk = to_ost_clk(hw);
+	const struct ingenic_ost_clk_info *info = ost_clk->info;
+	unsigned int prescale;
+
+	prescale = readl(ost_clk->ost->base + info->ostccr_reg);
+
+	prescale = FIELD_GET(OSTCCR_PRESCALE1_MASK, prescale);
+
+	return parent_rate >> (prescale * 2);
+}
+
+static unsigned long ingenic_ost_global_timer_recalc_rate(struct clk_hw *hw,
+		unsigned long parent_rate)
+{
+	struct ingenic_ost_clk *ost_clk = to_ost_clk(hw);
+	const struct ingenic_ost_clk_info *info = ost_clk->info;
+	unsigned int prescale;
+
+	prescale = readl(ost_clk->ost->base + info->ostccr_reg);
+
+	prescale = FIELD_GET(OSTCCR_PRESCALE2_MASK, prescale);
+
+	return parent_rate >> (prescale * 2);
+}
+
+static u8 ingenic_ost_get_prescale(unsigned long rate, unsigned long req_rate)
+{
+	u8 prescale;
+
+	for (prescale = 0; prescale < 2; prescale++)
+		if ((rate >> (prescale * 2)) <= req_rate)
+			return prescale;
+
+	return 2; /* /16 divider */
+}
+
+static int ingenic_ost_determine_rate(struct clk_hw *hw,
+				      struct clk_rate_request *req)
+{
+	unsigned long rate = req->best_parent_rate;
+	u8 prescale;
+
+	if (req->rate > rate) {
+		req->rate = rate;
+
+		return 0;
+	}
+
+	prescale = ingenic_ost_get_prescale(rate, req->rate);
+
+	req->rate = rate >> (prescale * 2);
+
+	return 0;
+}
+
+static int ingenic_ost_percpu_timer_set_rate(struct clk_hw *hw, unsigned long req_rate,
+		unsigned long parent_rate)
+{
+	struct ingenic_ost_clk *ost_clk = to_ost_clk(hw);
+	const struct ingenic_ost_clk_info *info = ost_clk->info;
+	u8 prescale = ingenic_ost_get_prescale(parent_rate, req_rate);
+	int val;
+
+	val = readl(ost_clk->ost->base + info->ostccr_reg);
+	val &= ~OSTCCR_PRESCALE1_MASK;
+	val |= FIELD_PREP(OSTCCR_PRESCALE1_MASK, prescale);
+	writel(val, ost_clk->ost->base + info->ostccr_reg);
+
+	return 0;
+}
+
+static int ingenic_ost_global_timer_set_rate(struct clk_hw *hw, unsigned long req_rate,
+		unsigned long parent_rate)
+{
+	struct ingenic_ost_clk *ost_clk = to_ost_clk(hw);
+	const struct ingenic_ost_clk_info *info = ost_clk->info;
+	u8 prescale = ingenic_ost_get_prescale(parent_rate, req_rate);
+	int val;
+
+	val = readl(ost_clk->ost->base + info->ostccr_reg);
+	val &= ~OSTCCR_PRESCALE2_MASK;
+	val |= FIELD_PREP(OSTCCR_PRESCALE2_MASK, prescale);
+	writel(val, ost_clk->ost->base + info->ostccr_reg);
+
+	return 0;
+}
+
+static const struct clk_ops ingenic_ost_percpu_timer_ops = {
+	.recalc_rate	= ingenic_ost_percpu_timer_recalc_rate,
+	.determine_rate = ingenic_ost_determine_rate,
+	.set_rate	= ingenic_ost_percpu_timer_set_rate,
+};
+
+static const struct clk_ops ingenic_ost_global_timer_ops = {
+	.recalc_rate	= ingenic_ost_global_timer_recalc_rate,
+	.determine_rate = ingenic_ost_determine_rate,
+	.set_rate	= ingenic_ost_global_timer_set_rate,
+};
+
+static const char * const ingenic_ost_clk_parents[] = { "ext" };
+
+static const struct ingenic_ost_clk_info x1000_ost_clk_info[] = {
+	[OST_CLK_PERCPU_TIMER] = {
+		.init_data = {
+			.name = "percpu timer",
+			.parent_names = ingenic_ost_clk_parents,
+			.num_parents = ARRAY_SIZE(ingenic_ost_clk_parents),
+			.ops = &ingenic_ost_percpu_timer_ops,
+			.flags = CLK_SET_RATE_UNGATE,
+		},
+		.ostccr_reg = OST_REG_OSTCCR,
+	},
+
+	[OST_CLK_GLOBAL_TIMER] = {
+		.init_data = {
+			.name = "global timer",
+			.parent_names = ingenic_ost_clk_parents,
+			.num_parents = ARRAY_SIZE(ingenic_ost_clk_parents),
+			.ops = &ingenic_ost_global_timer_ops,
+			.flags = CLK_SET_RATE_UNGATE,
+		},
+		.ostccr_reg = OST_REG_OSTCCR,
+	},
+};
+
+static u64 notrace ingenic_ost_global_timer_read_cntl(void)
+{
+	struct ingenic_ost *ost = ingenic_ost;
+	unsigned int count;
+
+	count = readl(ost->base + OST_REG_OST2CNTL);
+
+	return count;
+}
+
+static u64 notrace ingenic_ost_clocksource_read(struct clocksource *cs)
+{
+	return ingenic_ost_global_timer_read_cntl();
+}
+
+static inline struct ingenic_ost *to_ingenic_ost(struct clock_event_device *evt)
+{
+	return container_of(evt, struct ingenic_ost, cevt);
+}
+
+static int ingenic_ost_cevt_set_state_shutdown(struct clock_event_device *evt)
+{
+	struct ingenic_ost *ost = to_ingenic_ost(evt);
+
+	writel(OSTECR_OST1ENC, ost->base + OST_REG_OSTECR);
+
+	return 0;
+}
+
+static int ingenic_ost_cevt_set_next(unsigned long next,
+				     struct clock_event_device *evt)
+{
+	struct ingenic_ost *ost = to_ingenic_ost(evt);
+
+	writel((u32)~OSTFR_FFLAG, ost->base + OST_REG_OSTFR);
+	writel(next, ost->base + OST_REG_OST1DFR);
+	writel(OSTCR_OST1CLR, ost->base + OST_REG_OSTCR);
+	writel(OSTESR_OST1ENS, ost->base + OST_REG_OSTESR);
+	writel((u32)~OSTMR_FMASK, ost->base + OST_REG_OSTMR);
+
+	return 0;
+}
+
+static irqreturn_t ingenic_ost_cevt_cb(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+	struct ingenic_ost *ost = to_ingenic_ost(evt);
+
+	writel(OSTECR_OST1ENC, ost->base + OST_REG_OSTECR);
+
+	if (evt->event_handler)
+		evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static int __init ingenic_ost_register_clock(struct ingenic_ost *ost,
+			unsigned int idx, const struct ingenic_ost_clk_info *info,
+			struct clk_hw_onecell_data *clocks)
+{
+	struct ingenic_ost_clk *ost_clk;
+	int val, err;
+
+	ost_clk = kzalloc_obj(*ost_clk);
+	if (!ost_clk)
+		return -ENOMEM;
+
+	ost_clk->hw.init = &info->init_data;
+	ost_clk->idx = idx;
+	ost_clk->info = info;
+	ost_clk->ost = ost;
+
+	/* Reset clock divider */
+	val = readl(ost->base + info->ostccr_reg);
+	val &= ~(OSTCCR_PRESCALE1_MASK | OSTCCR_PRESCALE2_MASK);
+	writel(val, ost->base + info->ostccr_reg);
+
+	err = clk_hw_register(NULL, &ost_clk->hw);
+	if (err) {
+		kfree(ost_clk);
+		return err;
+	}
+
+	clocks->hws[idx] = &ost_clk->hw;
+
+	return 0;
+}
+
+static struct clk * __init ingenic_ost_get_clock(struct device_node *np, int id)
+{
+	struct of_phandle_args args;
+
+	args.np = np;
+	args.args_count = 1;
+	args.args[0] = id;
+
+	return of_clk_get_from_provider(&args);
+}
+
+static int __init ingenic_ost_percpu_timer_init(struct device_node *np,
+					 struct ingenic_ost *ost)
+{
+	unsigned int timer_virq, channel = OST_CLK_PERCPU_TIMER;
+	unsigned long rate;
+	int err;
+
+	ost->percpu_timer_clk = ingenic_ost_get_clock(np, channel);
+	if (IS_ERR(ost->percpu_timer_clk))
+		return PTR_ERR(ost->percpu_timer_clk);
+
+	err = clk_prepare_enable(ost->percpu_timer_clk);
+	if (err)
+		goto err_clk_put;
+
+	rate = clk_get_rate(ost->percpu_timer_clk);
+	if (!rate) {
+		err = -EINVAL;
+		goto err_clk_disable;
+	}
+
+	timer_virq = of_irq_get(np, 0);
+	if (!timer_virq) {
+		err = -EINVAL;
+		goto err_clk_disable;
+	}
+
+	snprintf(ost->name, sizeof(ost->name), "OST percpu timer");
+
+	err = request_irq(timer_virq, ingenic_ost_cevt_cb, IRQF_TIMER,
+			  ost->name, &ost->cevt);
+	if (err)
+		goto err_irq_dispose_mapping;
+
+	ost->cevt.cpumask = cpumask_of(smp_processor_id());
+	ost->cevt.features = CLOCK_EVT_FEAT_ONESHOT;
+	ost->cevt.name = ost->name;
+	ost->cevt.rating = 400;
+	ost->cevt.set_state_shutdown = ingenic_ost_cevt_set_state_shutdown;
+	ost->cevt.set_next_event = ingenic_ost_cevt_set_next;
+
+	clockevents_config_and_register(&ost->cevt, rate, 4, 0xffffffff);
+
+	return 0;
+
+err_irq_dispose_mapping:
+	irq_dispose_mapping(timer_virq);
+err_clk_disable:
+	clk_disable_unprepare(ost->percpu_timer_clk);
+err_clk_put:
+	clk_put(ost->percpu_timer_clk);
+	return err;
+}
+
+static int __init ingenic_ost_global_timer_init(struct device_node *np,
+					       struct ingenic_ost *ost)
+{
+	unsigned int channel = OST_CLK_GLOBAL_TIMER;
+	struct clocksource *cs = &ost->cs;
+	unsigned long rate;
+	int err;
+
+	ost->global_timer_clk = ingenic_ost_get_clock(np, channel);
+	if (IS_ERR(ost->global_timer_clk))
+		return PTR_ERR(ost->global_timer_clk);
+
+	err = clk_prepare_enable(ost->global_timer_clk);
+	if (err)
+		goto err_clk_put;
+
+	rate = clk_get_rate(ost->global_timer_clk);
+	if (!rate) {
+		err = -EINVAL;
+		goto err_clk_disable;
+	}
+
+	/* Clear counter CNT registers */
+	writel(OSTCR_OST2CLR, ost->base + OST_REG_OSTCR);
+
+	/* Enable OST channel */
+	writel(OSTESR_OST2ENS, ost->base + OST_REG_OSTESR);
+
+	cs->name = "ingenic-ost";
+	cs->rating = 400;
+	cs->flags = CLOCK_SOURCE_IS_CONTINUOUS;
+	cs->mask = CLOCKSOURCE_MASK(32);
+	cs->read = ingenic_ost_clocksource_read;
+
+	err = clocksource_register_hz(cs, rate);
+	if (err)
+		goto err_clk_disable;
+
+	return 0;
+
+err_clk_disable:
+	clk_disable_unprepare(ost->global_timer_clk);
+err_clk_put:
+	clk_put(ost->global_timer_clk);
+	return err;
+}
+
+static const struct ingenic_soc_info x1000_soc_info = {
+	.num_channels = 2,
+};
+
+static const struct of_device_id __maybe_unused ingenic_ost_of_matches[] __initconst = {
+	{ .compatible = "ingenic,x1000-ost", .data = &x1000_soc_info },
+	{ /* sentinel */ }
+};
+
+static int __init ingenic_ost_probe(struct device_node *np)
+{
+	const struct of_device_id *id = of_match_node(ingenic_ost_of_matches, np);
+	struct ingenic_ost *ost;
+	unsigned int i;
+	int ret;
+
+	ost = kzalloc_obj(*ost);
+	if (!ost)
+		return -ENOMEM;
+
+	ost->base = of_io_request_and_map(np, 0, of_node_full_name(np));
+	if (IS_ERR(ost->base)) {
+		pr_err("%s: Failed to map OST registers\n", __func__);
+		ret = PTR_ERR(ost->base);
+		goto err_free_ost;
+	}
+
+	ost->clk = of_clk_get_by_name(np, "ost");
+	if (IS_ERR(ost->clk)) {
+		ret = PTR_ERR(ost->clk);
+		pr_crit("%s: Cannot get OST clock\n", __func__);
+		goto err_free_ost;
+	}
+
+	ret = clk_prepare_enable(ost->clk);
+	if (ret) {
+		pr_crit("%s: Unable to enable OST clock\n", __func__);
+		goto err_put_clk;
+	}
+
+	ost->soc_info = id->data;
+
+	ost->clocks = kzalloc_flex(*ost->clocks, hws,
+				   ost->soc_info->num_channels);
+	if (!ost->clocks) {
+		ret = -ENOMEM;
+		goto err_clk_disable;
+	}
+
+	ost->clocks->num = ost->soc_info->num_channels;
+
+	for (i = 0; i < ost->clocks->num; i++) {
+		ret = ingenic_ost_register_clock(ost, i, &x1000_ost_clk_info[i], ost->clocks);
+		if (ret) {
+			pr_crit("%s: Cannot register clock %d\n", __func__, i);
+			goto err_unregister_ost_clocks;
+		}
+	}
+
+	ret = of_clk_add_hw_provider(np, of_clk_hw_onecell_get, ost->clocks);
+	if (ret) {
+		pr_crit("%s: Cannot add OF clock provider\n", __func__);
+		goto err_unregister_ost_clocks;
+	}
+
+	ingenic_ost = ost;
+
+	return 0;
+
+err_unregister_ost_clocks:
+	for (i = 0; i < ost->clocks->num; i++)
+		if (ost->clocks->hws[i])
+			clk_hw_unregister(ost->clocks->hws[i]);
+	kfree(ost->clocks);
+err_clk_disable:
+	clk_disable_unprepare(ost->clk);
+err_put_clk:
+	clk_put(ost->clk);
+err_free_ost:
+	kfree(ost);
+	return ret;
+}
+
+static int __init ingenic_ost_init(struct device_node *np)
+{
+	struct ingenic_ost *ost;
+	unsigned long rate;
+	int ret;
+
+	ret = ingenic_ost_probe(np);
+	if (ret) {
+		pr_crit("%s: Failed to initialize OST clocks: %d\n", __func__, ret);
+		return ret;
+	}
+
+	of_node_clear_flag(np, OF_POPULATED);
+
+	ost = ingenic_ost;
+	if (IS_ERR(ost))
+		return PTR_ERR(ost);
+
+	ret = ingenic_ost_global_timer_init(np, ost);
+	if (ret) {
+		pr_crit("%s: Unable to init global timer: %x\n", __func__, ret);
+		goto err_free_ingenic_ost;
+	}
+
+	ret = ingenic_ost_percpu_timer_init(np, ost);
+	if (ret)
+		goto err_ost_global_timer_cleanup;
+
+	/* Register the sched_clock at the end as there's no way to undo it */
+	rate = clk_get_rate(ost->global_timer_clk);
+	sched_clock_register(ingenic_ost_global_timer_read_cntl, 32, rate);
+
+	return 0;
+
+err_ost_global_timer_cleanup:
+	clocksource_unregister(&ost->cs);
+	clk_disable_unprepare(ost->global_timer_clk);
+	clk_put(ost->global_timer_clk);
+err_free_ingenic_ost:
+	kfree(ost);
+	return ret;
+}
+
+TIMER_OF_DECLARE(x1000_ost,  "ingenic,x1000-ost",  ingenic_ost_init);