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, 244 insertions, 0 deletions

diff --git a/drivers/clocksource/timer-imx-tpm.c b/drivers/clocksource/timer-imx-tpm.c
new file mode 100644
index 000000000..92c025b70
--- /dev/null
+++ b/drivers/clocksource/timer-imx-tpm.c
@@ -0,0 +1,244 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// Copyright 2016 Freescale Semiconductor, Inc.
+// Copyright 2017 NXP
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/sched_clock.h>
+
+#include "timer-of.h"
+
+#define TPM_PARAM			0x4
+#define TPM_PARAM_WIDTH_SHIFT		16
+#define TPM_PARAM_WIDTH_MASK		(0xff << 16)
+#define TPM_SC				0x10
+#define TPM_SC_CMOD_INC_PER_CNT		(0x1 << 3)
+#define TPM_SC_CMOD_DIV_DEFAULT		0x3
+#define TPM_SC_CMOD_DIV_MAX		0x7
+#define TPM_SC_TOF_MASK			(0x1 << 7)
+#define TPM_CNT				0x14
+#define TPM_MOD				0x18
+#define TPM_STATUS			0x1c
+#define TPM_STATUS_CH0F			BIT(0)
+#define TPM_C0SC			0x20
+#define TPM_C0SC_CHIE			BIT(6)
+#define TPM_C0SC_MODE_SHIFT		2
+#define TPM_C0SC_MODE_MASK		0x3c
+#define TPM_C0SC_MODE_SW_COMPARE	0x4
+#define TPM_C0SC_CHF_MASK		(0x1 << 7)
+#define TPM_C0V				0x24
+
+static int counter_width __ro_after_init;
+static void __iomem *timer_base __ro_after_init;
+
+static inline void tpm_timer_disable(void)
+{
+	unsigned int val;
+
+	/* channel disable */
+	val = readl(timer_base + TPM_C0SC);
+	val &= ~(TPM_C0SC_MODE_MASK | TPM_C0SC_CHIE);
+	writel(val, timer_base + TPM_C0SC);
+}
+
+static inline void tpm_timer_enable(void)
+{
+	unsigned int val;
+
+	/* channel enabled in sw compare mode */
+	val = readl(timer_base + TPM_C0SC);
+	val |= (TPM_C0SC_MODE_SW_COMPARE << TPM_C0SC_MODE_SHIFT) |
+	       TPM_C0SC_CHIE;
+	writel(val, timer_base + TPM_C0SC);
+}
+
+static inline void tpm_irq_acknowledge(void)
+{
+	writel(TPM_STATUS_CH0F, timer_base + TPM_STATUS);
+}
+
+static inline unsigned long tpm_read_counter(void)
+{
+	return readl(timer_base + TPM_CNT);
+}
+
+#if defined(CONFIG_ARM)
+static struct delay_timer tpm_delay_timer;
+
+static unsigned long tpm_read_current_timer(void)
+{
+	return tpm_read_counter();
+}
+
+static u64 notrace tpm_read_sched_clock(void)
+{
+	return tpm_read_counter();
+}
+#endif
+
+static int tpm_set_next_event(unsigned long delta,
+				struct clock_event_device *evt)
+{
+	unsigned long next, prev, now;
+
+	prev = tpm_read_counter();
+	next = prev + delta;
+	writel(next, timer_base + TPM_C0V);
+	now = tpm_read_counter();
+
+	/*
+	 * Need to wait CNT increase at least 1 cycle to make sure
+	 * the C0V has been updated into HW.
+	 */
+	if ((next & 0xffffffff) != readl(timer_base + TPM_C0V))
+		while (now == tpm_read_counter())
+			;
+
+	/*
+	 * NOTE: We observed in a very small probability, the bus fabric
+	 * contention between GPU and A7 may results a few cycles delay
+	 * of writing CNT registers which may cause the min_delta event got
+	 * missed, so we need add a ETIME check here in case it happened.
+	 */
+	return (now - prev) >= delta ? -ETIME : 0;
+}
+
+static int tpm_set_state_oneshot(struct clock_event_device *evt)
+{
+	tpm_timer_enable();
+
+	return 0;
+}
+
+static int tpm_set_state_shutdown(struct clock_event_device *evt)
+{
+	tpm_timer_disable();
+
+	return 0;
+}
+
+static irqreturn_t tpm_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	tpm_irq_acknowledge();
+
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static struct timer_of to_tpm = {
+	.flags = TIMER_OF_IRQ | TIMER_OF_BASE | TIMER_OF_CLOCK,
+	.clkevt = {
+		.name			= "i.MX TPM Timer",
+		.rating			= 200,
+		.features		= CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_DYNIRQ,
+		.set_state_shutdown	= tpm_set_state_shutdown,
+		.set_state_oneshot	= tpm_set_state_oneshot,
+		.set_next_event		= tpm_set_next_event,
+		.cpumask		= cpu_possible_mask,
+	},
+	.of_irq = {
+		.handler		= tpm_timer_interrupt,
+		.flags			= IRQF_TIMER,
+	},
+	.of_clk = {
+		.name = "per",
+	},
+};
+
+static int __init tpm_clocksource_init(void)
+{
+#if defined(CONFIG_ARM)
+	tpm_delay_timer.read_current_timer = &tpm_read_current_timer;
+	tpm_delay_timer.freq = timer_of_rate(&to_tpm) >> 3;
+	register_current_timer_delay(&tpm_delay_timer);
+
+	sched_clock_register(tpm_read_sched_clock, counter_width,
+			     timer_of_rate(&to_tpm) >> 3);
+#endif
+
+	return clocksource_mmio_init(timer_base + TPM_CNT,
+				     "imx-tpm",
+				     timer_of_rate(&to_tpm) >> 3,
+				     to_tpm.clkevt.rating,
+				     counter_width,
+				     clocksource_mmio_readl_up);
+}
+
+static void __init tpm_clockevent_init(void)
+{
+	clockevents_config_and_register(&to_tpm.clkevt,
+					timer_of_rate(&to_tpm) >> 3,
+					300,
+					GENMASK(counter_width - 1,
+					1));
+}
+
+static int __init tpm_timer_init(struct device_node *np)
+{
+	struct clk *ipg;
+	int ret;
+
+	ipg = of_clk_get_by_name(np, "ipg");
+	if (IS_ERR(ipg)) {
+		pr_err("tpm: failed to get ipg clk\n");
+		return -ENODEV;
+	}
+	/* enable clk before accessing registers */
+	ret = clk_prepare_enable(ipg);
+	if (ret) {
+		pr_err("tpm: ipg clock enable failed (%d)\n", ret);
+		clk_put(ipg);
+		return ret;
+	}
+
+	ret = timer_of_init(np, &to_tpm);
+	if (ret)
+		return ret;
+
+	timer_base = timer_of_base(&to_tpm);
+
+	counter_width = (readl(timer_base + TPM_PARAM)
+		& TPM_PARAM_WIDTH_MASK) >> TPM_PARAM_WIDTH_SHIFT;
+	/* use rating 200 for 32-bit counter and 150 for 16-bit counter */
+	to_tpm.clkevt.rating = counter_width == 0x20 ? 200 : 150;
+
+	/*
+	 * Initialize tpm module to a known state
+	 * 1) Counter disabled
+	 * 2) TPM counter operates in up counting mode
+	 * 3) Timer Overflow Interrupt disabled
+	 * 4) Channel0 disabled
+	 * 5) DMA transfers disabled
+	 */
+	/* make sure counter is disabled */
+	writel(0, timer_base + TPM_SC);
+	/* TOF is W1C */
+	writel(TPM_SC_TOF_MASK, timer_base + TPM_SC);
+	writel(0, timer_base + TPM_CNT);
+	/* CHF is W1C */
+	writel(TPM_C0SC_CHF_MASK, timer_base + TPM_C0SC);
+
+	/*
+	 * increase per cnt,
+	 * div 8 for 32-bit counter and div 128 for 16-bit counter
+	 */
+	writel(TPM_SC_CMOD_INC_PER_CNT |
+		(counter_width == 0x20 ?
+		TPM_SC_CMOD_DIV_DEFAULT : TPM_SC_CMOD_DIV_MAX),
+		timer_base + TPM_SC);
+
+	/* set MOD register to maximum for free running mode */
+	writel(GENMASK(counter_width - 1, 0), timer_base + TPM_MOD);
+
+	tpm_clockevent_init();
+
+	return tpm_clocksource_init();
+}
+TIMER_OF_DECLARE(imx7ulp, "fsl,imx7ulp-tpm", tpm_timer_init);