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, 421 insertions, 0 deletions

diff --git a/drivers/clocksource/ingenic-timer.c b/drivers/clocksource/ingenic-timer.c
new file mode 100644
index 000000000..54bb56005
--- /dev/null
+++ b/drivers/clocksource/ingenic-timer.c
@@ -0,0 +1,421 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Ingenic SoCs TCU IRQ driver
+ * Copyright (C) 2019 Paul Cercueil <paul@crapouillou.net>
+ * Copyright (C) 2020 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
+ */
+
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/cpuhotplug.h>
+#include <linux/interrupt.h>
+#include <linux/mfd/ingenic-tcu.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/overflow.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/sched_clock.h>
+
+#include <dt-bindings/clock/ingenic,tcu.h>
+
+static DEFINE_PER_CPU(call_single_data_t, ingenic_cevt_csd);
+
+struct ingenic_soc_info {
+	unsigned int num_channels;
+};
+
+struct ingenic_tcu_timer {
+	unsigned int cpu;
+	unsigned int channel;
+	struct clock_event_device cevt;
+	struct clk *clk;
+	char name[8];
+};
+
+struct ingenic_tcu {
+	struct regmap *map;
+	struct device_node *np;
+	struct clk *cs_clk;
+	unsigned int cs_channel;
+	struct clocksource cs;
+	unsigned long pwm_channels_mask;
+	struct ingenic_tcu_timer timers[];
+};
+
+static struct ingenic_tcu *ingenic_tcu;
+
+static u64 notrace ingenic_tcu_timer_read(void)
+{
+	struct ingenic_tcu *tcu = ingenic_tcu;
+	unsigned int count;
+
+	regmap_read(tcu->map, TCU_REG_TCNTc(tcu->cs_channel), &count);
+
+	return count;
+}
+
+static u64 notrace ingenic_tcu_timer_cs_read(struct clocksource *cs)
+{
+	return ingenic_tcu_timer_read();
+}
+
+static inline struct ingenic_tcu *
+to_ingenic_tcu(struct ingenic_tcu_timer *timer)
+{
+	return container_of(timer, struct ingenic_tcu, timers[timer->cpu]);
+}
+
+static inline struct ingenic_tcu_timer *
+to_ingenic_tcu_timer(struct clock_event_device *evt)
+{
+	return container_of(evt, struct ingenic_tcu_timer, cevt);
+}
+
+static int ingenic_tcu_cevt_set_state_shutdown(struct clock_event_device *evt)
+{
+	struct ingenic_tcu_timer *timer = to_ingenic_tcu_timer(evt);
+	struct ingenic_tcu *tcu = to_ingenic_tcu(timer);
+
+	regmap_write(tcu->map, TCU_REG_TECR, BIT(timer->channel));
+
+	return 0;
+}
+
+static int ingenic_tcu_cevt_set_next(unsigned long next,
+				     struct clock_event_device *evt)
+{
+	struct ingenic_tcu_timer *timer = to_ingenic_tcu_timer(evt);
+	struct ingenic_tcu *tcu = to_ingenic_tcu(timer);
+
+	if (next > 0xffff)
+		return -EINVAL;
+
+	regmap_write(tcu->map, TCU_REG_TDFRc(timer->channel), next);
+	regmap_write(tcu->map, TCU_REG_TCNTc(timer->channel), 0);
+	regmap_write(tcu->map, TCU_REG_TESR, BIT(timer->channel));
+
+	return 0;
+}
+
+static void ingenic_per_cpu_event_handler(void *info)
+{
+	struct clock_event_device *cevt = (struct clock_event_device *) info;
+
+	cevt->event_handler(cevt);
+}
+
+static irqreturn_t ingenic_tcu_cevt_cb(int irq, void *dev_id)
+{
+	struct ingenic_tcu_timer *timer = dev_id;
+	struct ingenic_tcu *tcu = to_ingenic_tcu(timer);
+	call_single_data_t *csd;
+
+	regmap_write(tcu->map, TCU_REG_TECR, BIT(timer->channel));
+
+	if (timer->cevt.event_handler) {
+		csd = &per_cpu(ingenic_cevt_csd, timer->cpu);
+		csd->info = (void *) &timer->cevt;
+		csd->func = ingenic_per_cpu_event_handler;
+		smp_call_function_single_async(timer->cpu, csd);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static struct clk *ingenic_tcu_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 ingenic_tcu_setup_cevt(unsigned int cpu)
+{
+	struct ingenic_tcu *tcu = ingenic_tcu;
+	struct ingenic_tcu_timer *timer = &tcu->timers[cpu];
+	unsigned int timer_virq;
+	struct irq_domain *domain;
+	unsigned long rate;
+	int err;
+
+	timer->clk = ingenic_tcu_get_clock(tcu->np, timer->channel);
+	if (IS_ERR(timer->clk))
+		return PTR_ERR(timer->clk);
+
+	err = clk_prepare_enable(timer->clk);
+	if (err)
+		goto err_clk_put;
+
+	rate = clk_get_rate(timer->clk);
+	if (!rate) {
+		err = -EINVAL;
+		goto err_clk_disable;
+	}
+
+	domain = irq_find_host(tcu->np);
+	if (!domain) {
+		err = -ENODEV;
+		goto err_clk_disable;
+	}
+
+	timer_virq = irq_create_mapping(domain, timer->channel);
+	if (!timer_virq) {
+		err = -EINVAL;
+		goto err_clk_disable;
+	}
+
+	snprintf(timer->name, sizeof(timer->name), "TCU%u", timer->channel);
+
+	err = request_irq(timer_virq, ingenic_tcu_cevt_cb, IRQF_TIMER,
+			  timer->name, timer);
+	if (err)
+		goto err_irq_dispose_mapping;
+
+	timer->cpu = smp_processor_id();
+	timer->cevt.cpumask = cpumask_of(smp_processor_id());
+	timer->cevt.features = CLOCK_EVT_FEAT_ONESHOT;
+	timer->cevt.name = timer->name;
+	timer->cevt.rating = 200;
+	timer->cevt.set_state_shutdown = ingenic_tcu_cevt_set_state_shutdown;
+	timer->cevt.set_next_event = ingenic_tcu_cevt_set_next;
+
+	clockevents_config_and_register(&timer->cevt, rate, 10, 0xffff);
+
+	return 0;
+
+err_irq_dispose_mapping:
+	irq_dispose_mapping(timer_virq);
+err_clk_disable:
+	clk_disable_unprepare(timer->clk);
+err_clk_put:
+	clk_put(timer->clk);
+	return err;
+}
+
+static int __init ingenic_tcu_clocksource_init(struct device_node *np,
+					       struct ingenic_tcu *tcu)
+{
+	unsigned int channel = tcu->cs_channel;
+	struct clocksource *cs = &tcu->cs;
+	unsigned long rate;
+	int err;
+
+	tcu->cs_clk = ingenic_tcu_get_clock(np, channel);
+	if (IS_ERR(tcu->cs_clk))
+		return PTR_ERR(tcu->cs_clk);
+
+	err = clk_prepare_enable(tcu->cs_clk);
+	if (err)
+		goto err_clk_put;
+
+	rate = clk_get_rate(tcu->cs_clk);
+	if (!rate) {
+		err = -EINVAL;
+		goto err_clk_disable;
+	}
+
+	/* Reset channel */
+	regmap_update_bits(tcu->map, TCU_REG_TCSRc(channel),
+			   0xffff & ~TCU_TCSR_RESERVED_BITS, 0);
+
+	/* Reset counter */
+	regmap_write(tcu->map, TCU_REG_TDFRc(channel), 0xffff);
+	regmap_write(tcu->map, TCU_REG_TCNTc(channel), 0);
+
+	/* Enable channel */
+	regmap_write(tcu->map, TCU_REG_TESR, BIT(channel));
+
+	cs->name = "ingenic-timer";
+	cs->rating = 200;
+	cs->flags = CLOCK_SOURCE_IS_CONTINUOUS;
+	cs->mask = CLOCKSOURCE_MASK(16);
+	cs->read = ingenic_tcu_timer_cs_read;
+
+	err = clocksource_register_hz(cs, rate);
+	if (err)
+		goto err_clk_disable;
+
+	return 0;
+
+err_clk_disable:
+	clk_disable_unprepare(tcu->cs_clk);
+err_clk_put:
+	clk_put(tcu->cs_clk);
+	return err;
+}
+
+static const struct ingenic_soc_info jz4740_soc_info = {
+	.num_channels = 8,
+};
+
+static const struct ingenic_soc_info jz4725b_soc_info = {
+	.num_channels = 6,
+};
+
+static const struct of_device_id ingenic_tcu_of_match[] = {
+	{ .compatible = "ingenic,jz4740-tcu", .data = &jz4740_soc_info, },
+	{ .compatible = "ingenic,jz4725b-tcu", .data = &jz4725b_soc_info, },
+	{ .compatible = "ingenic,jz4760-tcu", .data = &jz4740_soc_info, },
+	{ .compatible = "ingenic,jz4770-tcu", .data = &jz4740_soc_info, },
+	{ .compatible = "ingenic,x1000-tcu", .data = &jz4740_soc_info, },
+	{ /* sentinel */ }
+};
+
+static int __init ingenic_tcu_init(struct device_node *np)
+{
+	const struct of_device_id *id = of_match_node(ingenic_tcu_of_match, np);
+	const struct ingenic_soc_info *soc_info = id->data;
+	struct ingenic_tcu_timer *timer;
+	struct ingenic_tcu *tcu;
+	struct regmap *map;
+	unsigned int cpu;
+	int ret, last_bit = -1;
+	long rate;
+
+	of_node_clear_flag(np, OF_POPULATED);
+
+	map = device_node_to_regmap(np);
+	if (IS_ERR(map))
+		return PTR_ERR(map);
+
+	tcu = kzalloc_flex(*tcu, timers, num_possible_cpus());
+	if (!tcu)
+		return -ENOMEM;
+
+	/*
+	 * Enable all TCU channels for PWM use by default except channels 0/1,
+	 * and channel 2 if target CPU is JZ4780/X2000 and SMP is selected.
+	 */
+	tcu->pwm_channels_mask = GENMASK(soc_info->num_channels - 1,
+					 num_possible_cpus() + 1);
+	of_property_read_u32(np, "ingenic,pwm-channels-mask",
+			     (u32 *)&tcu->pwm_channels_mask);
+
+	/* Verify that we have at least num_possible_cpus() + 1 free channels */
+	if (hweight8(tcu->pwm_channels_mask) >
+			soc_info->num_channels - num_possible_cpus() + 1) {
+		pr_crit("%s: Invalid PWM channel mask: 0x%02lx\n", __func__,
+			tcu->pwm_channels_mask);
+		ret = -EINVAL;
+		goto err_free_ingenic_tcu;
+	}
+
+	tcu->map = map;
+	tcu->np = np;
+	ingenic_tcu = tcu;
+
+	for (cpu = 0; cpu < num_possible_cpus(); cpu++) {
+		timer = &tcu->timers[cpu];
+
+		timer->cpu = cpu;
+		timer->channel = find_next_zero_bit(&tcu->pwm_channels_mask,
+						  soc_info->num_channels,
+						  last_bit + 1);
+		last_bit = timer->channel;
+	}
+
+	tcu->cs_channel = find_next_zero_bit(&tcu->pwm_channels_mask,
+					     soc_info->num_channels,
+					     last_bit + 1);
+
+	ret = ingenic_tcu_clocksource_init(np, tcu);
+	if (ret) {
+		pr_crit("%s: Unable to init clocksource: %d\n", __func__, ret);
+		goto err_free_ingenic_tcu;
+	}
+
+	/* Setup clock events on each CPU core */
+	ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "Ingenic XBurst: online",
+				ingenic_tcu_setup_cevt, NULL);
+	if (ret < 0) {
+		pr_crit("%s: Unable to start CPU timers: %d\n", __func__, ret);
+		goto err_tcu_clocksource_cleanup;
+	}
+
+	/* Register the sched_clock at the end as there's no way to undo it */
+	rate = clk_get_rate(tcu->cs_clk);
+	sched_clock_register(ingenic_tcu_timer_read, 16, rate);
+
+	return 0;
+
+err_tcu_clocksource_cleanup:
+	clocksource_unregister(&tcu->cs);
+	clk_disable_unprepare(tcu->cs_clk);
+	clk_put(tcu->cs_clk);
+err_free_ingenic_tcu:
+	kfree(tcu);
+	return ret;
+}
+
+TIMER_OF_DECLARE(jz4740_tcu_intc,  "ingenic,jz4740-tcu",  ingenic_tcu_init);
+TIMER_OF_DECLARE(jz4725b_tcu_intc, "ingenic,jz4725b-tcu", ingenic_tcu_init);
+TIMER_OF_DECLARE(jz4760_tcu_intc,  "ingenic,jz4760-tcu",  ingenic_tcu_init);
+TIMER_OF_DECLARE(jz4770_tcu_intc,  "ingenic,jz4770-tcu",  ingenic_tcu_init);
+TIMER_OF_DECLARE(x1000_tcu_intc,  "ingenic,x1000-tcu",  ingenic_tcu_init);
+
+static int __init ingenic_tcu_probe(struct platform_device *pdev)
+{
+	platform_set_drvdata(pdev, ingenic_tcu);
+
+	return 0;
+}
+
+static int ingenic_tcu_suspend(struct device *dev)
+{
+	struct ingenic_tcu *tcu = dev_get_drvdata(dev);
+	unsigned int cpu;
+
+	clk_disable(tcu->cs_clk);
+
+	for (cpu = 0; cpu < num_online_cpus(); cpu++)
+		clk_disable(tcu->timers[cpu].clk);
+
+	return 0;
+}
+
+static int ingenic_tcu_resume(struct device *dev)
+{
+	struct ingenic_tcu *tcu = dev_get_drvdata(dev);
+	unsigned int cpu;
+	int ret;
+
+	for (cpu = 0; cpu < num_online_cpus(); cpu++) {
+		ret = clk_enable(tcu->timers[cpu].clk);
+		if (ret)
+			goto err_timer_clk_disable;
+	}
+
+	ret = clk_enable(tcu->cs_clk);
+	if (ret)
+		goto err_timer_clk_disable;
+
+	return 0;
+
+err_timer_clk_disable:
+	for (; cpu > 0; cpu--)
+		clk_disable(tcu->timers[cpu - 1].clk);
+	return ret;
+}
+
+static const struct dev_pm_ops ingenic_tcu_pm_ops = {
+	/* _noirq: We want the TCU clocks to be gated last / ungated first */
+	.suspend_noirq = ingenic_tcu_suspend,
+	.resume_noirq  = ingenic_tcu_resume,
+};
+
+static struct platform_driver ingenic_tcu_driver = {
+	.driver = {
+		.name	= "ingenic-tcu-timer",
+		.pm	= pm_sleep_ptr(&ingenic_tcu_pm_ops),
+		.of_match_table = ingenic_tcu_of_match,
+	},
+};
+builtin_platform_driver_probe(ingenic_tcu_driver, ingenic_tcu_probe);