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, 339 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-asm9260.c b/drivers/rtc/rtc-asm9260.c
new file mode 100644
index 000000000..705470ae8
--- /dev/null
+++ b/drivers/rtc/rtc-asm9260.c
@@ -0,0 +1,339 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2016 Oleksij Rempel <linux@rempel-privat.de>
+ */
+
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+
+/* Miscellaneous registers */
+/* Interrupt Location Register */
+#define HW_ILR			0x00
+#define BM_RTCALF		BIT(1)
+#define BM_RTCCIF		BIT(0)
+
+/* Clock Control Register */
+#define HW_CCR			0x08
+/* Calibration counter disable */
+#define BM_CCALOFF		BIT(4)
+/* Reset internal oscillator divider */
+#define BM_CTCRST		BIT(1)
+/* Clock Enable */
+#define BM_CLKEN		BIT(0)
+
+/* Counter Increment Interrupt Register */
+#define HW_CIIR			0x0C
+#define BM_CIIR_IMYEAR		BIT(7)
+#define BM_CIIR_IMMON		BIT(6)
+#define BM_CIIR_IMDOY		BIT(5)
+#define BM_CIIR_IMDOW		BIT(4)
+#define BM_CIIR_IMDOM		BIT(3)
+#define BM_CIIR_IMHOUR		BIT(2)
+#define BM_CIIR_IMMIN		BIT(1)
+#define BM_CIIR_IMSEC		BIT(0)
+
+/* Alarm Mask Register */
+#define HW_AMR			0x10
+#define BM_AMR_IMYEAR		BIT(7)
+#define BM_AMR_IMMON		BIT(6)
+#define BM_AMR_IMDOY		BIT(5)
+#define BM_AMR_IMDOW		BIT(4)
+#define BM_AMR_IMDOM		BIT(3)
+#define BM_AMR_IMHOUR		BIT(2)
+#define BM_AMR_IMMIN		BIT(1)
+#define BM_AMR_IMSEC		BIT(0)
+#define BM_AMR_OFF		0xff
+
+/* Consolidated time registers */
+#define HW_CTIME0		0x14
+#define BM_CTIME0_DOW_S		24
+#define BM_CTIME0_DOW_M		0x7
+#define BM_CTIME0_HOUR_S	16
+#define BM_CTIME0_HOUR_M	0x1f
+#define BM_CTIME0_MIN_S		8
+#define BM_CTIME0_MIN_M		0x3f
+#define BM_CTIME0_SEC_S		0
+#define BM_CTIME0_SEC_M		0x3f
+
+#define HW_CTIME1		0x18
+#define BM_CTIME1_YEAR_S	16
+#define BM_CTIME1_YEAR_M	0xfff
+#define BM_CTIME1_MON_S		8
+#define BM_CTIME1_MON_M		0xf
+#define BM_CTIME1_DOM_S		0
+#define BM_CTIME1_DOM_M		0x1f
+
+#define HW_CTIME2		0x1C
+#define BM_CTIME2_DOY_S		0
+#define BM_CTIME2_DOY_M		0xfff
+
+/* Time counter registers */
+#define HW_SEC			0x20
+#define HW_MIN			0x24
+#define HW_HOUR			0x28
+#define HW_DOM			0x2C
+#define HW_DOW			0x30
+#define HW_DOY			0x34
+#define HW_MONTH		0x38
+#define HW_YEAR			0x3C
+
+#define HW_CALIBRATION		0x40
+#define BM_CALDIR_BACK		BIT(17)
+#define BM_CALVAL_M		0x1ffff
+
+/* General purpose registers */
+#define HW_GPREG0		0x44
+#define HW_GPREG1		0x48
+#define HW_GPREG2		0x4C
+#define HW_GPREG3		0x50
+#define HW_GPREG4		0x54
+
+/* Alarm register group */
+#define HW_ALSEC		0x60
+#define HW_ALMIN		0x64
+#define HW_ALHOUR		0x68
+#define HW_ALDOM		0x6C
+#define HW_ALDOW		0x70
+#define HW_ALDOY		0x74
+#define HW_ALMON		0x78
+#define HW_ALYEAR		0x7C
+
+struct asm9260_rtc_priv {
+	struct device		*dev;
+	void __iomem		*iobase;
+	struct rtc_device	*rtc;
+	struct clk		*clk;
+};
+
+static irqreturn_t asm9260_rtc_irq(int irq, void *dev_id)
+{
+	struct asm9260_rtc_priv *priv = dev_id;
+	u32 isr;
+	unsigned long events = 0;
+
+	rtc_lock(priv->rtc);
+	isr = ioread32(priv->iobase + HW_CIIR);
+	if (!isr) {
+		rtc_unlock(priv->rtc);
+		return IRQ_NONE;
+	}
+
+	iowrite32(0, priv->iobase + HW_CIIR);
+	rtc_unlock(priv->rtc);
+
+	events |= RTC_AF | RTC_IRQF;
+
+	rtc_update_irq(priv->rtc, 1, events);
+
+	return IRQ_HANDLED;
+}
+
+static int asm9260_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+	struct asm9260_rtc_priv *priv = dev_get_drvdata(dev);
+	u32 ctime0, ctime1, ctime2;
+
+	ctime0 = ioread32(priv->iobase + HW_CTIME0);
+	ctime1 = ioread32(priv->iobase + HW_CTIME1);
+	ctime2 = ioread32(priv->iobase + HW_CTIME2);
+
+	if (ctime1 != ioread32(priv->iobase + HW_CTIME1)) {
+		/*
+		 * woops, counter flipped right now. Now we are safe
+		 * to reread.
+		 */
+		ctime0 = ioread32(priv->iobase + HW_CTIME0);
+		ctime1 = ioread32(priv->iobase + HW_CTIME1);
+		ctime2 = ioread32(priv->iobase + HW_CTIME2);
+	}
+
+	tm->tm_sec  = (ctime0 >> BM_CTIME0_SEC_S)  & BM_CTIME0_SEC_M;
+	tm->tm_min  = (ctime0 >> BM_CTIME0_MIN_S)  & BM_CTIME0_MIN_M;
+	tm->tm_hour = (ctime0 >> BM_CTIME0_HOUR_S) & BM_CTIME0_HOUR_M;
+	tm->tm_wday = (ctime0 >> BM_CTIME0_DOW_S)  & BM_CTIME0_DOW_M;
+
+	tm->tm_mday = (ctime1 >> BM_CTIME1_DOM_S)  & BM_CTIME1_DOM_M;
+	tm->tm_mon  = (ctime1 >> BM_CTIME1_MON_S)  & BM_CTIME1_MON_M;
+	tm->tm_year = (ctime1 >> BM_CTIME1_YEAR_S) & BM_CTIME1_YEAR_M;
+
+	tm->tm_yday = (ctime2 >> BM_CTIME2_DOY_S)  & BM_CTIME2_DOY_M;
+
+	return 0;
+}
+
+static int asm9260_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+	struct asm9260_rtc_priv *priv = dev_get_drvdata(dev);
+
+	/*
+	 * make sure SEC counter will not flip other counter on write time,
+	 * real value will be written at the enf of sequence.
+	 */
+	iowrite32(0, priv->iobase + HW_SEC);
+
+	iowrite32(tm->tm_year, priv->iobase + HW_YEAR);
+	iowrite32(tm->tm_mon,  priv->iobase + HW_MONTH);
+	iowrite32(tm->tm_mday, priv->iobase + HW_DOM);
+	iowrite32(tm->tm_wday, priv->iobase + HW_DOW);
+	iowrite32(tm->tm_yday, priv->iobase + HW_DOY);
+	iowrite32(tm->tm_hour, priv->iobase + HW_HOUR);
+	iowrite32(tm->tm_min,  priv->iobase + HW_MIN);
+	iowrite32(tm->tm_sec,  priv->iobase + HW_SEC);
+
+	return 0;
+}
+
+static int asm9260_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct asm9260_rtc_priv *priv = dev_get_drvdata(dev);
+
+	alrm->time.tm_year = ioread32(priv->iobase + HW_ALYEAR);
+	alrm->time.tm_mon  = ioread32(priv->iobase + HW_ALMON);
+	alrm->time.tm_mday = ioread32(priv->iobase + HW_ALDOM);
+	alrm->time.tm_wday = ioread32(priv->iobase + HW_ALDOW);
+	alrm->time.tm_yday = ioread32(priv->iobase + HW_ALDOY);
+	alrm->time.tm_hour = ioread32(priv->iobase + HW_ALHOUR);
+	alrm->time.tm_min  = ioread32(priv->iobase + HW_ALMIN);
+	alrm->time.tm_sec  = ioread32(priv->iobase + HW_ALSEC);
+
+	alrm->enabled = ioread32(priv->iobase + HW_AMR) ? 1 : 0;
+	alrm->pending = ioread32(priv->iobase + HW_CIIR) ? 1 : 0;
+
+	return rtc_valid_tm(&alrm->time);
+}
+
+static int asm9260_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct asm9260_rtc_priv *priv = dev_get_drvdata(dev);
+
+	iowrite32(alrm->time.tm_year, priv->iobase + HW_ALYEAR);
+	iowrite32(alrm->time.tm_mon,  priv->iobase + HW_ALMON);
+	iowrite32(alrm->time.tm_mday, priv->iobase + HW_ALDOM);
+	iowrite32(alrm->time.tm_wday, priv->iobase + HW_ALDOW);
+	iowrite32(alrm->time.tm_yday, priv->iobase + HW_ALDOY);
+	iowrite32(alrm->time.tm_hour, priv->iobase + HW_ALHOUR);
+	iowrite32(alrm->time.tm_min,  priv->iobase + HW_ALMIN);
+	iowrite32(alrm->time.tm_sec,  priv->iobase + HW_ALSEC);
+
+	iowrite32(alrm->enabled ? 0 : BM_AMR_OFF, priv->iobase + HW_AMR);
+
+	return 0;
+}
+
+static int asm9260_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+	struct asm9260_rtc_priv *priv = dev_get_drvdata(dev);
+
+	iowrite32(enabled ? 0 : BM_AMR_OFF, priv->iobase + HW_AMR);
+	return 0;
+}
+
+static const struct rtc_class_ops asm9260_rtc_ops = {
+	.read_time		= asm9260_rtc_read_time,
+	.set_time		= asm9260_rtc_set_time,
+	.read_alarm		= asm9260_rtc_read_alarm,
+	.set_alarm		= asm9260_rtc_set_alarm,
+	.alarm_irq_enable	= asm9260_alarm_irq_enable,
+};
+
+static int asm9260_rtc_probe(struct platform_device *pdev)
+{
+	struct asm9260_rtc_priv *priv;
+	struct device *dev = &pdev->dev;
+	int irq_alarm, ret;
+	u32 ccr;
+
+	priv = devm_kzalloc(dev, sizeof(struct asm9260_rtc_priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->dev = &pdev->dev;
+	platform_set_drvdata(pdev, priv);
+
+	irq_alarm = platform_get_irq(pdev, 0);
+	if (irq_alarm < 0)
+		return irq_alarm;
+
+	priv->iobase = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(priv->iobase))
+		return PTR_ERR(priv->iobase);
+
+	priv->clk = devm_clk_get(dev, "ahb");
+	if (IS_ERR(priv->clk))
+		return PTR_ERR(priv->clk);
+
+	ret = clk_prepare_enable(priv->clk);
+	if (ret) {
+		dev_err(dev, "Failed to enable clk!\n");
+		return ret;
+	}
+
+	ccr = ioread32(priv->iobase + HW_CCR);
+	/* if dev is not enabled, reset it */
+	if ((ccr & (BM_CLKEN | BM_CTCRST)) != BM_CLKEN) {
+		iowrite32(BM_CTCRST, priv->iobase + HW_CCR);
+		ccr = 0;
+	}
+
+	iowrite32(BM_CLKEN | ccr, priv->iobase + HW_CCR);
+	iowrite32(0, priv->iobase + HW_CIIR);
+	iowrite32(BM_AMR_OFF, priv->iobase + HW_AMR);
+
+	priv->rtc = devm_rtc_device_register(dev, dev_name(dev),
+					     &asm9260_rtc_ops, THIS_MODULE);
+	if (IS_ERR(priv->rtc)) {
+		ret = PTR_ERR(priv->rtc);
+		dev_err(dev, "Failed to register RTC device: %d\n", ret);
+		goto err_return;
+	}
+
+	ret = devm_request_threaded_irq(dev, irq_alarm, NULL,
+					asm9260_rtc_irq, IRQF_ONESHOT,
+					dev_name(dev), priv);
+	if (ret < 0) {
+		dev_err(dev, "can't get irq %i, err %d\n",
+			irq_alarm, ret);
+		goto err_return;
+	}
+
+	return 0;
+
+err_return:
+	clk_disable_unprepare(priv->clk);
+	return ret;
+}
+
+static void asm9260_rtc_remove(struct platform_device *pdev)
+{
+	struct asm9260_rtc_priv *priv = platform_get_drvdata(pdev);
+
+	/* Disable alarm matching */
+	iowrite32(BM_AMR_OFF, priv->iobase + HW_AMR);
+	clk_disable_unprepare(priv->clk);
+}
+
+static const struct of_device_id asm9260_dt_ids[] = {
+	{ .compatible = "alphascale,asm9260-rtc", },
+	{}
+};
+MODULE_DEVICE_TABLE(of, asm9260_dt_ids);
+
+static struct platform_driver asm9260_rtc_driver = {
+	.probe		= asm9260_rtc_probe,
+	.remove		= asm9260_rtc_remove,
+	.driver		= {
+		.name	= "asm9260-rtc",
+		.of_match_table = asm9260_dt_ids,
+	},
+};
+
+module_platform_driver(asm9260_rtc_driver);
+
+MODULE_AUTHOR("Oleksij Rempel <linux@rempel-privat.de>");
+MODULE_DESCRIPTION("Alphascale asm9260 SoC Realtime Clock Driver (RTC)");
+MODULE_LICENSE("GPL");