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, 243 insertions, 0 deletions

diff --git a/drivers/clocksource/asm9260_timer.c b/drivers/clocksource/asm9260_timer.c
new file mode 100644
index 000000000..8f97ab0b0
--- /dev/null
+++ b/drivers/clocksource/asm9260_timer.c
@@ -0,0 +1,243 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2014 Oleksij Rempel <linux@rempel-privat.de>
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/clk.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/bitops.h>
+
+#define DRIVER_NAME	"asm9260-timer"
+
+/*
+ * this device provide 4 offsets for each register:
+ * 0x0 - plain read write mode
+ * 0x4 - set mode, OR logic.
+ * 0x8 - clr mode, XOR logic.
+ * 0xc - togle mode.
+ */
+#define SET_REG 4
+#define CLR_REG 8
+
+#define HW_IR           0x0000 /* RW. Interrupt */
+#define BM_IR_CR0	BIT(4)
+#define BM_IR_MR3	BIT(3)
+#define BM_IR_MR2	BIT(2)
+#define BM_IR_MR1	BIT(1)
+#define BM_IR_MR0	BIT(0)
+
+#define HW_TCR		0x0010 /* RW. Timer controller */
+/* BM_C*_RST
+ * Timer Counter and the Prescale Counter are synchronously reset on the
+ * next positive edge of PCLK. The counters remain reset until TCR[1] is
+ * returned to zero. */
+#define BM_C3_RST	BIT(7)
+#define BM_C2_RST	BIT(6)
+#define BM_C1_RST	BIT(5)
+#define BM_C0_RST	BIT(4)
+/* BM_C*_EN
+ * 1 - Timer Counter and Prescale Counter are enabled for counting
+ * 0 - counters are disabled */
+#define BM_C3_EN	BIT(3)
+#define BM_C2_EN	BIT(2)
+#define BM_C1_EN	BIT(1)
+#define BM_C0_EN	BIT(0)
+
+#define HW_DIR		0x0020 /* RW. Direction? */
+/* 00 - count up
+ * 01 - count down
+ * 10 - ?? 2^n/2 */
+#define BM_DIR_COUNT_UP		0
+#define BM_DIR_COUNT_DOWN	1
+#define BM_DIR0_SHIFT	0
+#define BM_DIR1_SHIFT	4
+#define BM_DIR2_SHIFT	8
+#define BM_DIR3_SHIFT	12
+#define BM_DIR_DEFAULT		(BM_DIR_COUNT_UP << BM_DIR0_SHIFT | \
+				 BM_DIR_COUNT_UP << BM_DIR1_SHIFT | \
+				 BM_DIR_COUNT_UP << BM_DIR2_SHIFT | \
+				 BM_DIR_COUNT_UP << BM_DIR3_SHIFT)
+
+#define HW_TC0		0x0030 /* RO. Timer counter 0 */
+/* HW_TC*. Timer counter owerflow (0xffff.ffff to 0x0000.0000) do not generate
+ * interrupt. This registers can be used to detect overflow */
+#define HW_TC1          0x0040
+#define HW_TC2		0x0050
+#define HW_TC3		0x0060
+
+#define HW_PR		0x0070 /* RW. prescaler */
+#define BM_PR_DISABLE	0
+#define HW_PC		0x0080 /* RO. Prescaler counter */
+#define HW_MCR		0x0090 /* RW. Match control */
+/* enable interrupt on match */
+#define BM_MCR_INT_EN(n)	(1 << (n * 3 + 0))
+/* enable TC reset on match */
+#define BM_MCR_RES_EN(n)	(1 << (n * 3 + 1))
+/* enable stop TC on match */
+#define BM_MCR_STOP_EN(n)	(1 << (n * 3 + 2))
+
+#define HW_MR0		0x00a0 /* RW. Match reg */
+#define HW_MR1		0x00b0
+#define HW_MR2		0x00C0
+#define HW_MR3		0x00D0
+
+#define HW_CTCR		0x0180 /* Counter control */
+#define BM_CTCR0_SHIFT	0
+#define BM_CTCR1_SHIFT	2
+#define BM_CTCR2_SHIFT	4
+#define BM_CTCR3_SHIFT	6
+#define BM_CTCR_TM	0	/* Timer mode. Every rising PCLK edge. */
+#define BM_CTCR_DEFAULT	(BM_CTCR_TM << BM_CTCR0_SHIFT | \
+			 BM_CTCR_TM << BM_CTCR1_SHIFT | \
+			 BM_CTCR_TM << BM_CTCR2_SHIFT | \
+			 BM_CTCR_TM << BM_CTCR3_SHIFT)
+
+static struct asm9260_timer_priv {
+	void __iomem *base;
+	unsigned long ticks_per_jiffy;
+} priv;
+
+static int asm9260_timer_set_next_event(unsigned long delta,
+					 struct clock_event_device *evt)
+{
+	/* configure match count for TC0 */
+	writel_relaxed(delta, priv.base + HW_MR0);
+	/* enable TC0 */
+	writel_relaxed(BM_C0_EN, priv.base + HW_TCR + SET_REG);
+	return 0;
+}
+
+static inline void __asm9260_timer_shutdown(struct clock_event_device *evt)
+{
+	/* stop timer0 */
+	writel_relaxed(BM_C0_EN, priv.base + HW_TCR + CLR_REG);
+}
+
+static int asm9260_timer_shutdown(struct clock_event_device *evt)
+{
+	__asm9260_timer_shutdown(evt);
+	return 0;
+}
+
+static int asm9260_timer_set_oneshot(struct clock_event_device *evt)
+{
+	__asm9260_timer_shutdown(evt);
+
+	/* enable reset and stop on match */
+	writel_relaxed(BM_MCR_RES_EN(0) | BM_MCR_STOP_EN(0),
+		       priv.base + HW_MCR + SET_REG);
+	return 0;
+}
+
+static int asm9260_timer_set_periodic(struct clock_event_device *evt)
+{
+	__asm9260_timer_shutdown(evt);
+
+	/* disable reset and stop on match */
+	writel_relaxed(BM_MCR_RES_EN(0) | BM_MCR_STOP_EN(0),
+		       priv.base + HW_MCR + CLR_REG);
+	/* configure match count for TC0 */
+	writel_relaxed(priv.ticks_per_jiffy, priv.base + HW_MR0);
+	/* enable TC0 */
+	writel_relaxed(BM_C0_EN, priv.base + HW_TCR + SET_REG);
+	return 0;
+}
+
+static struct clock_event_device event_dev = {
+	.name			= DRIVER_NAME,
+	.rating			= 200,
+	.features		= CLOCK_EVT_FEAT_PERIODIC |
+				  CLOCK_EVT_FEAT_ONESHOT,
+	.set_next_event		= asm9260_timer_set_next_event,
+	.set_state_shutdown	= asm9260_timer_shutdown,
+	.set_state_periodic	= asm9260_timer_set_periodic,
+	.set_state_oneshot	= asm9260_timer_set_oneshot,
+	.tick_resume		= asm9260_timer_shutdown,
+};
+
+static irqreturn_t asm9260_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	evt->event_handler(evt);
+
+	writel_relaxed(BM_IR_MR0, priv.base + HW_IR);
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * ---------------------------------------------------------------------------
+ * Timer initialization
+ * ---------------------------------------------------------------------------
+ */
+static int __init asm9260_timer_init(struct device_node *np)
+{
+	int irq;
+	struct clk *clk;
+	int ret;
+	unsigned long rate;
+
+	priv.base = of_io_request_and_map(np, 0, np->name);
+	if (IS_ERR(priv.base)) {
+		pr_err("%pOFn: unable to map resource\n", np);
+		return PTR_ERR(priv.base);
+	}
+
+	clk = of_clk_get(np, 0);
+	if (IS_ERR(clk)) {
+		pr_err("Failed to get clk!\n");
+		return PTR_ERR(clk);
+	}
+
+	ret = clk_prepare_enable(clk);
+	if (ret) {
+		pr_err("Failed to enable clk!\n");
+		return ret;
+	}
+
+	irq = irq_of_parse_and_map(np, 0);
+	ret = request_irq(irq, asm9260_timer_interrupt, IRQF_TIMER,
+			DRIVER_NAME, &event_dev);
+	if (ret) {
+		pr_err("Failed to setup irq!\n");
+		clk_disable_unprepare(clk);
+		return ret;
+	}
+
+	/* set all timers for count-up */
+	writel_relaxed(BM_DIR_DEFAULT, priv.base + HW_DIR);
+	/* disable divider */
+	writel_relaxed(BM_PR_DISABLE, priv.base + HW_PR);
+	/* make sure all timers use every rising PCLK edge. */
+	writel_relaxed(BM_CTCR_DEFAULT, priv.base + HW_CTCR);
+	/* enable interrupt for TC0 and clean setting for all other lines */
+	writel_relaxed(BM_MCR_INT_EN(0) , priv.base + HW_MCR);
+
+	rate = clk_get_rate(clk);
+	clocksource_mmio_init(priv.base + HW_TC1, DRIVER_NAME, rate,
+			200, 32, clocksource_mmio_readl_up);
+
+	/* Seems like we can't use counter without match register even if
+	 * actions for MR are disabled. So, set MR to max value. */
+	writel_relaxed(0xffffffff, priv.base + HW_MR1);
+	/* enable TC1 */
+	writel_relaxed(BM_C1_EN, priv.base + HW_TCR + SET_REG);
+
+	priv.ticks_per_jiffy = DIV_ROUND_CLOSEST(rate, HZ);
+	event_dev.cpumask = cpumask_of(0);
+	clockevents_config_and_register(&event_dev, rate, 0x2c00, 0xfffffffe);
+
+	return 0;
+}
+TIMER_OF_DECLARE(asm9260_timer, "alphascale,asm9260-timer",
+		asm9260_timer_init);