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, 459 insertions, 0 deletions

diff --git a/drivers/clocksource/timer-fttmr010.c b/drivers/clocksource/timer-fttmr010.c
new file mode 100644
index 000000000..308f94bfb
--- /dev/null
+++ b/drivers/clocksource/timer-fttmr010.c
@@ -0,0 +1,459 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Faraday Technology FTTMR010 timer driver
+ * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org>
+ *
+ * Based on a rewrite of arch/arm/mach-gemini/timer.c:
+ * Copyright (C) 2001-2006 Storlink, Corp.
+ * Copyright (C) 2008-2009 Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
+ */
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/sched_clock.h>
+#include <linux/clk.h>
+#include <linux/slab.h>
+#include <linux/bitops.h>
+#include <linux/delay.h>
+
+/*
+ * Register definitions common for all the timer variants.
+ */
+#define TIMER1_COUNT		(0x00)
+#define TIMER1_LOAD		(0x04)
+#define TIMER1_MATCH1		(0x08)
+#define TIMER1_MATCH2		(0x0c)
+#define TIMER2_COUNT		(0x10)
+#define TIMER2_LOAD		(0x14)
+#define TIMER2_MATCH1		(0x18)
+#define TIMER2_MATCH2		(0x1c)
+#define TIMER3_COUNT		(0x20)
+#define TIMER3_LOAD		(0x24)
+#define TIMER3_MATCH1		(0x28)
+#define TIMER3_MATCH2		(0x2c)
+#define TIMER_CR		(0x30)
+
+/*
+ * Control register set to clear for ast2600 only.
+ */
+#define AST2600_TIMER_CR_CLR	(0x3c)
+
+/*
+ * Control register (TMC30) bit fields for fttmr010/gemini/moxart timers.
+ */
+#define TIMER_1_CR_ENABLE	BIT(0)
+#define TIMER_1_CR_CLOCK	BIT(1)
+#define TIMER_1_CR_INT		BIT(2)
+#define TIMER_2_CR_ENABLE	BIT(3)
+#define TIMER_2_CR_CLOCK	BIT(4)
+#define TIMER_2_CR_INT		BIT(5)
+#define TIMER_3_CR_ENABLE	BIT(6)
+#define TIMER_3_CR_CLOCK	BIT(7)
+#define TIMER_3_CR_INT		BIT(8)
+#define TIMER_1_CR_UPDOWN	BIT(9)
+#define TIMER_2_CR_UPDOWN	BIT(10)
+#define TIMER_3_CR_UPDOWN	BIT(11)
+
+/*
+ * Control register (TMC30) bit fields for aspeed ast2400/ast2500 timers.
+ * The aspeed timers move bits around in the control register and lacks
+ * bits for setting the timer to count upwards.
+ */
+#define TIMER_1_CR_ASPEED_ENABLE	BIT(0)
+#define TIMER_1_CR_ASPEED_CLOCK		BIT(1)
+#define TIMER_1_CR_ASPEED_INT		BIT(2)
+#define TIMER_2_CR_ASPEED_ENABLE	BIT(4)
+#define TIMER_2_CR_ASPEED_CLOCK		BIT(5)
+#define TIMER_2_CR_ASPEED_INT		BIT(6)
+#define TIMER_3_CR_ASPEED_ENABLE	BIT(8)
+#define TIMER_3_CR_ASPEED_CLOCK		BIT(9)
+#define TIMER_3_CR_ASPEED_INT		BIT(10)
+
+/*
+ * Interrupt status/mask register definitions for fttmr010/gemini/moxart
+ * timers.
+ * The registers don't exist and they are not needed on aspeed timers
+ * because:
+ *   - aspeed timer overflow interrupt is controlled by bits in Control
+ *     Register (TMC30).
+ *   - aspeed timers always generate interrupt when either one of the
+ *     Match registers equals to Status register.
+ */
+#define TIMER_INTR_STATE	(0x34)
+#define TIMER_INTR_MASK		(0x38)
+#define TIMER_1_INT_MATCH1	BIT(0)
+#define TIMER_1_INT_MATCH2	BIT(1)
+#define TIMER_1_INT_OVERFLOW	BIT(2)
+#define TIMER_2_INT_MATCH1	BIT(3)
+#define TIMER_2_INT_MATCH2	BIT(4)
+#define TIMER_2_INT_OVERFLOW	BIT(5)
+#define TIMER_3_INT_MATCH1	BIT(6)
+#define TIMER_3_INT_MATCH2	BIT(7)
+#define TIMER_3_INT_OVERFLOW	BIT(8)
+#define TIMER_INT_ALL_MASK	0x1ff
+
+struct fttmr010 {
+	void __iomem *base;
+	unsigned int tick_rate;
+	bool is_aspeed;
+	u32 t1_enable_val;
+	struct clock_event_device clkevt;
+	int (*timer_shutdown)(struct clock_event_device *evt);
+#ifdef CONFIG_ARM
+	struct delay_timer delay_timer;
+#endif
+};
+
+/*
+ * A local singleton used by sched_clock and delay timer reads, which are
+ * fast and stateless
+ */
+static struct fttmr010 *local_fttmr;
+
+static inline struct fttmr010 *to_fttmr010(struct clock_event_device *evt)
+{
+	return container_of(evt, struct fttmr010, clkevt);
+}
+
+static unsigned long fttmr010_read_current_timer_up(void)
+{
+	return readl(local_fttmr->base + TIMER2_COUNT);
+}
+
+static unsigned long fttmr010_read_current_timer_down(void)
+{
+	return ~readl(local_fttmr->base + TIMER2_COUNT);
+}
+
+static u64 notrace fttmr010_read_sched_clock_up(void)
+{
+	return fttmr010_read_current_timer_up();
+}
+
+static u64 notrace fttmr010_read_sched_clock_down(void)
+{
+	return fttmr010_read_current_timer_down();
+}
+
+static int fttmr010_timer_set_next_event(unsigned long cycles,
+				       struct clock_event_device *evt)
+{
+	struct fttmr010 *fttmr010 = to_fttmr010(evt);
+	u32 cr;
+
+	/* Stop */
+	fttmr010->timer_shutdown(evt);
+
+	if (fttmr010->is_aspeed) {
+		/*
+		 * ASPEED Timer Controller will load TIMER1_LOAD register
+		 * into TIMER1_COUNT register when the timer is re-enabled.
+		 */
+		writel(cycles, fttmr010->base + TIMER1_LOAD);
+	} else {
+		/* Setup the match register forward in time */
+		cr = readl(fttmr010->base + TIMER1_COUNT);
+		writel(cr + cycles, fttmr010->base + TIMER1_MATCH1);
+	}
+
+	/* Start */
+	cr = readl(fttmr010->base + TIMER_CR);
+	cr |= fttmr010->t1_enable_val;
+	writel(cr, fttmr010->base + TIMER_CR);
+
+	return 0;
+}
+
+static int ast2600_timer_shutdown(struct clock_event_device *evt)
+{
+	struct fttmr010 *fttmr010 = to_fttmr010(evt);
+
+	/* Stop */
+	writel(fttmr010->t1_enable_val, fttmr010->base + AST2600_TIMER_CR_CLR);
+
+	return 0;
+}
+
+static int fttmr010_timer_shutdown(struct clock_event_device *evt)
+{
+	struct fttmr010 *fttmr010 = to_fttmr010(evt);
+	u32 cr;
+
+	/* Stop */
+	cr = readl(fttmr010->base + TIMER_CR);
+	cr &= ~fttmr010->t1_enable_val;
+	writel(cr, fttmr010->base + TIMER_CR);
+
+	return 0;
+}
+
+static int fttmr010_timer_set_oneshot(struct clock_event_device *evt)
+{
+	struct fttmr010 *fttmr010 = to_fttmr010(evt);
+	u32 cr;
+
+	/* Stop */
+	fttmr010->timer_shutdown(evt);
+
+	/* Setup counter start from 0 or ~0 */
+	writel(0, fttmr010->base + TIMER1_COUNT);
+	if (fttmr010->is_aspeed) {
+		writel(~0, fttmr010->base + TIMER1_LOAD);
+	} else {
+		writel(0, fttmr010->base + TIMER1_LOAD);
+
+		/* Enable interrupt */
+		cr = readl(fttmr010->base + TIMER_INTR_MASK);
+		cr &= ~(TIMER_1_INT_OVERFLOW | TIMER_1_INT_MATCH2);
+		cr |= TIMER_1_INT_MATCH1;
+		writel(cr, fttmr010->base + TIMER_INTR_MASK);
+	}
+
+	return 0;
+}
+
+static int fttmr010_timer_set_periodic(struct clock_event_device *evt)
+{
+	struct fttmr010 *fttmr010 = to_fttmr010(evt);
+	u32 period = DIV_ROUND_CLOSEST(fttmr010->tick_rate, HZ);
+	u32 cr;
+
+	/* Stop */
+	fttmr010->timer_shutdown(evt);
+
+	/* Setup timer to fire at 1/HZ intervals. */
+	if (fttmr010->is_aspeed) {
+		writel(period, fttmr010->base + TIMER1_LOAD);
+	} else {
+		cr = 0xffffffff - (period - 1);
+		writel(cr, fttmr010->base + TIMER1_COUNT);
+		writel(cr, fttmr010->base + TIMER1_LOAD);
+
+		/* Enable interrupt on overflow */
+		cr = readl(fttmr010->base + TIMER_INTR_MASK);
+		cr &= ~(TIMER_1_INT_MATCH1 | TIMER_1_INT_MATCH2);
+		cr |= TIMER_1_INT_OVERFLOW;
+		writel(cr, fttmr010->base + TIMER_INTR_MASK);
+	}
+
+	/* Start the timer */
+	cr = readl(fttmr010->base + TIMER_CR);
+	cr |= fttmr010->t1_enable_val;
+	writel(cr, fttmr010->base + TIMER_CR);
+
+	return 0;
+}
+
+/*
+ * IRQ handler for the timer
+ */
+static irqreturn_t fttmr010_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	evt->event_handler(evt);
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t ast2600_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+	struct fttmr010 *fttmr010 = to_fttmr010(evt);
+
+	writel(0x1, fttmr010->base + TIMER_INTR_STATE);
+
+	evt->event_handler(evt);
+	return IRQ_HANDLED;
+}
+
+static int __init fttmr010_common_init(struct device_node *np,
+				       bool is_aspeed, bool is_ast2600)
+{
+	struct fttmr010 *fttmr010;
+	int irq;
+	struct clk *clk;
+	int ret;
+	u32 val;
+
+	/*
+	 * These implementations require a clock reference.
+	 * FIXME: we currently only support clocking using PCLK
+	 * and using EXTCLK is not supported in the driver.
+	 */
+	clk = of_clk_get_by_name(np, "PCLK");
+	if (IS_ERR(clk)) {
+		pr_err("could not get PCLK\n");
+		return PTR_ERR(clk);
+	}
+	ret = clk_prepare_enable(clk);
+	if (ret) {
+		pr_err("failed to enable PCLK\n");
+		return ret;
+	}
+
+	fttmr010 = kzalloc_obj(*fttmr010);
+	if (!fttmr010) {
+		ret = -ENOMEM;
+		goto out_disable_clock;
+	}
+	fttmr010->tick_rate = clk_get_rate(clk);
+
+	fttmr010->base = of_iomap(np, 0);
+	if (!fttmr010->base) {
+		pr_err("Can't remap registers\n");
+		ret = -ENXIO;
+		goto out_free;
+	}
+	/* IRQ for timer 1 */
+	irq = irq_of_parse_and_map(np, 0);
+	if (irq <= 0) {
+		pr_err("Can't parse IRQ\n");
+		ret = -EINVAL;
+		goto out_unmap;
+	}
+
+	/*
+	 * The Aspeed timers move bits around in the control register.
+	 */
+	if (is_aspeed) {
+		fttmr010->t1_enable_val = TIMER_1_CR_ASPEED_ENABLE |
+			TIMER_1_CR_ASPEED_INT;
+		fttmr010->is_aspeed = true;
+	} else {
+		fttmr010->t1_enable_val = TIMER_1_CR_ENABLE | TIMER_1_CR_INT;
+
+		/*
+		 * Reset the interrupt mask and status
+		 */
+		writel(TIMER_INT_ALL_MASK, fttmr010->base + TIMER_INTR_MASK);
+		writel(0, fttmr010->base + TIMER_INTR_STATE);
+	}
+
+	/*
+	 * Enable timer 1 count up, timer 2 count up, except on Aspeed,
+	 * where everything just counts down.
+	 */
+	if (is_aspeed)
+		val = TIMER_2_CR_ASPEED_ENABLE;
+	else {
+		val = TIMER_2_CR_ENABLE | TIMER_1_CR_UPDOWN |
+			TIMER_2_CR_UPDOWN;
+	}
+	writel(val, fttmr010->base + TIMER_CR);
+
+	/*
+	 * Setup free-running clocksource timer (interrupts
+	 * disabled.)
+	 */
+	local_fttmr = fttmr010;
+	writel(0, fttmr010->base + TIMER2_COUNT);
+	writel(0, fttmr010->base + TIMER2_MATCH1);
+	writel(0, fttmr010->base + TIMER2_MATCH2);
+
+	if (fttmr010->is_aspeed) {
+		writel(~0, fttmr010->base + TIMER2_LOAD);
+		clocksource_mmio_init(fttmr010->base + TIMER2_COUNT,
+				      "FTTMR010-TIMER2",
+				      fttmr010->tick_rate,
+				      300, 32, clocksource_mmio_readl_down);
+		sched_clock_register(fttmr010_read_sched_clock_down, 32,
+				     fttmr010->tick_rate);
+	} else {
+		writel(0, fttmr010->base + TIMER2_LOAD);
+		clocksource_mmio_init(fttmr010->base + TIMER2_COUNT,
+				      "FTTMR010-TIMER2",
+				      fttmr010->tick_rate,
+				      300, 32, clocksource_mmio_readl_up);
+		sched_clock_register(fttmr010_read_sched_clock_up, 32,
+				     fttmr010->tick_rate);
+	}
+
+	/*
+	 * Setup clockevent timer (interrupt-driven) on timer 1.
+	 */
+	writel(0, fttmr010->base + TIMER1_COUNT);
+	writel(0, fttmr010->base + TIMER1_LOAD);
+	writel(0, fttmr010->base + TIMER1_MATCH1);
+	writel(0, fttmr010->base + TIMER1_MATCH2);
+
+	if (is_ast2600) {
+		fttmr010->timer_shutdown = ast2600_timer_shutdown;
+		ret = request_irq(irq, ast2600_timer_interrupt,
+				  IRQF_TIMER, "FTTMR010-TIMER1",
+				  &fttmr010->clkevt);
+	} else {
+		fttmr010->timer_shutdown = fttmr010_timer_shutdown;
+		ret = request_irq(irq, fttmr010_timer_interrupt,
+				  IRQF_TIMER, "FTTMR010-TIMER1",
+				  &fttmr010->clkevt);
+	}
+	if (ret) {
+		pr_err("FTTMR010-TIMER1 no IRQ\n");
+		goto out_unmap;
+	}
+
+	fttmr010->clkevt.name = "FTTMR010-TIMER1";
+	/* Reasonably fast and accurate clock event */
+	fttmr010->clkevt.rating = 300;
+	fttmr010->clkevt.features = CLOCK_EVT_FEAT_PERIODIC |
+		CLOCK_EVT_FEAT_ONESHOT;
+	fttmr010->clkevt.set_next_event = fttmr010_timer_set_next_event;
+	fttmr010->clkevt.set_state_shutdown = fttmr010->timer_shutdown;
+	fttmr010->clkevt.set_state_periodic = fttmr010_timer_set_periodic;
+	fttmr010->clkevt.set_state_oneshot = fttmr010_timer_set_oneshot;
+	fttmr010->clkevt.tick_resume = fttmr010->timer_shutdown;
+	fttmr010->clkevt.cpumask = cpumask_of(0);
+	fttmr010->clkevt.irq = irq;
+	clockevents_config_and_register(&fttmr010->clkevt,
+					fttmr010->tick_rate,
+					1, 0xffffffff);
+
+#ifdef CONFIG_ARM
+	/* Also use this timer for delays */
+	if (fttmr010->is_aspeed)
+		fttmr010->delay_timer.read_current_timer =
+			fttmr010_read_current_timer_down;
+	else
+		fttmr010->delay_timer.read_current_timer =
+			fttmr010_read_current_timer_up;
+	fttmr010->delay_timer.freq = fttmr010->tick_rate;
+	register_current_timer_delay(&fttmr010->delay_timer);
+#endif
+
+	return 0;
+
+out_unmap:
+	iounmap(fttmr010->base);
+out_free:
+	kfree(fttmr010);
+out_disable_clock:
+	clk_disable_unprepare(clk);
+
+	return ret;
+}
+
+static __init int ast2600_timer_init(struct device_node *np)
+{
+	return fttmr010_common_init(np, true, true);
+}
+
+static __init int aspeed_timer_init(struct device_node *np)
+{
+	return fttmr010_common_init(np, true, false);
+}
+
+static __init int fttmr010_timer_init(struct device_node *np)
+{
+	return fttmr010_common_init(np, false, false);
+}
+
+TIMER_OF_DECLARE(fttmr010, "faraday,fttmr010", fttmr010_timer_init);
+TIMER_OF_DECLARE(gemini, "cortina,gemini-timer", fttmr010_timer_init);
+TIMER_OF_DECLARE(moxart, "moxa,moxart-timer", fttmr010_timer_init);
+TIMER_OF_DECLARE(ast2400, "aspeed,ast2400-timer", aspeed_timer_init);
+TIMER_OF_DECLARE(ast2500, "aspeed,ast2500-timer", aspeed_timer_init);
+TIMER_OF_DECLARE(ast2600, "aspeed,ast2600-timer", ast2600_timer_init);