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, 413 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-mt2712.c b/drivers/rtc/rtc-mt2712.c
new file mode 100644
index 000000000..cd92a9788
--- /dev/null
+++ b/drivers/rtc/rtc-mt2712.c
@@ -0,0 +1,413 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2019 MediaTek Inc.
+ * Author: Ran Bi <ran.bi@mediatek.com>
+ */
+
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/irqdomain.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+
+#define MT2712_BBPU		0x0000
+#define MT2712_BBPU_CLRPKY	BIT(4)
+#define MT2712_BBPU_RELOAD	BIT(5)
+#define MT2712_BBPU_CBUSY	BIT(6)
+#define MT2712_BBPU_KEY		(0x43 << 8)
+
+#define MT2712_IRQ_STA		0x0004
+#define MT2712_IRQ_STA_AL	BIT(0)
+#define MT2712_IRQ_STA_TC	BIT(1)
+
+#define MT2712_IRQ_EN		0x0008
+#define MT2712_IRQ_EN_AL	BIT(0)
+#define MT2712_IRQ_EN_TC	BIT(1)
+#define MT2712_IRQ_EN_ONESHOT	BIT(2)
+
+#define MT2712_CII_EN		0x000c
+
+#define MT2712_AL_MASK		0x0010
+#define MT2712_AL_MASK_DOW	BIT(4)
+
+#define MT2712_TC_SEC		0x0014
+#define MT2712_TC_MIN		0x0018
+#define MT2712_TC_HOU		0x001c
+#define MT2712_TC_DOM		0x0020
+#define MT2712_TC_DOW		0x0024
+#define MT2712_TC_MTH		0x0028
+#define MT2712_TC_YEA		0x002c
+
+#define MT2712_AL_SEC		0x0030
+#define MT2712_AL_MIN		0x0034
+#define MT2712_AL_HOU		0x0038
+#define MT2712_AL_DOM		0x003c
+#define MT2712_AL_DOW		0x0040
+#define MT2712_AL_MTH		0x0044
+#define MT2712_AL_YEA		0x0048
+
+#define MT2712_SEC_MASK		0x003f
+#define MT2712_MIN_MASK		0x003f
+#define MT2712_HOU_MASK		0x001f
+#define MT2712_DOM_MASK		0x001f
+#define MT2712_DOW_MASK		0x0007
+#define MT2712_MTH_MASK		0x000f
+#define MT2712_YEA_MASK		0x007f
+
+#define MT2712_POWERKEY1	0x004c
+#define MT2712_POWERKEY2	0x0050
+#define MT2712_POWERKEY1_KEY	0xa357
+#define MT2712_POWERKEY2_KEY	0x67d2
+
+#define MT2712_CON0		0x005c
+#define MT2712_CON1		0x0060
+
+#define MT2712_PROT		0x0070
+#define MT2712_PROT_UNLOCK1	0x9136
+#define MT2712_PROT_UNLOCK2	0x586a
+
+#define MT2712_WRTGR		0x0078
+
+#define MT2712_RTC_TIMESTAMP_END_2127	4985971199LL
+
+struct mt2712_rtc {
+	struct rtc_device	*rtc;
+	void __iomem		*base;
+	int			irq;
+	u8			irq_wake_enabled;
+	u8			powerlost;
+};
+
+static inline u32 mt2712_readl(struct mt2712_rtc *mt2712_rtc, u32 reg)
+{
+	return readl(mt2712_rtc->base + reg);
+}
+
+static inline void mt2712_writel(struct mt2712_rtc *mt2712_rtc,
+				 u32 reg, u32 val)
+{
+	writel(val, mt2712_rtc->base + reg);
+}
+
+static void mt2712_rtc_write_trigger(struct mt2712_rtc *mt2712_rtc)
+{
+	unsigned long timeout = jiffies + HZ / 10;
+
+	mt2712_writel(mt2712_rtc, MT2712_WRTGR, 1);
+	while (1) {
+		if (!(mt2712_readl(mt2712_rtc, MT2712_BBPU)
+					& MT2712_BBPU_CBUSY))
+			break;
+
+		if (time_after(jiffies, timeout)) {
+			dev_err(&mt2712_rtc->rtc->dev,
+				"%s time out!\n", __func__);
+			break;
+		}
+		cpu_relax();
+	}
+}
+
+static void mt2712_rtc_writeif_unlock(struct mt2712_rtc *mt2712_rtc)
+{
+	mt2712_writel(mt2712_rtc, MT2712_PROT, MT2712_PROT_UNLOCK1);
+	mt2712_rtc_write_trigger(mt2712_rtc);
+	mt2712_writel(mt2712_rtc, MT2712_PROT, MT2712_PROT_UNLOCK2);
+	mt2712_rtc_write_trigger(mt2712_rtc);
+}
+
+static irqreturn_t rtc_irq_handler_thread(int irq, void *data)
+{
+	struct mt2712_rtc *mt2712_rtc = data;
+	u16 irqsta;
+
+	/* Clear interrupt */
+	irqsta = mt2712_readl(mt2712_rtc, MT2712_IRQ_STA);
+	if (irqsta & MT2712_IRQ_STA_AL) {
+		rtc_update_irq(mt2712_rtc->rtc, 1, RTC_IRQF | RTC_AF);
+		return IRQ_HANDLED;
+	}
+
+	return IRQ_NONE;
+}
+
+static void __mt2712_rtc_read_time(struct mt2712_rtc *mt2712_rtc,
+				   struct rtc_time *tm, int *sec)
+{
+	tm->tm_sec  = mt2712_readl(mt2712_rtc, MT2712_TC_SEC)
+			& MT2712_SEC_MASK;
+	tm->tm_min  = mt2712_readl(mt2712_rtc, MT2712_TC_MIN)
+			& MT2712_MIN_MASK;
+	tm->tm_hour = mt2712_readl(mt2712_rtc, MT2712_TC_HOU)
+			& MT2712_HOU_MASK;
+	tm->tm_mday = mt2712_readl(mt2712_rtc, MT2712_TC_DOM)
+			& MT2712_DOM_MASK;
+	tm->tm_mon  = (mt2712_readl(mt2712_rtc, MT2712_TC_MTH) - 1)
+			& MT2712_MTH_MASK;
+	tm->tm_year = (mt2712_readl(mt2712_rtc, MT2712_TC_YEA) + 100)
+			& MT2712_YEA_MASK;
+
+	*sec = mt2712_readl(mt2712_rtc, MT2712_TC_SEC) & MT2712_SEC_MASK;
+}
+
+static int mt2712_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+	struct mt2712_rtc *mt2712_rtc = dev_get_drvdata(dev);
+	int sec;
+
+	if (mt2712_rtc->powerlost)
+		return -EINVAL;
+
+	do {
+		__mt2712_rtc_read_time(mt2712_rtc, tm, &sec);
+	} while (sec < tm->tm_sec);	/* SEC has carried */
+
+	return 0;
+}
+
+static int mt2712_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+	struct mt2712_rtc *mt2712_rtc = dev_get_drvdata(dev);
+
+	mt2712_writel(mt2712_rtc, MT2712_TC_SEC, tm->tm_sec  & MT2712_SEC_MASK);
+	mt2712_writel(mt2712_rtc, MT2712_TC_MIN, tm->tm_min  & MT2712_MIN_MASK);
+	mt2712_writel(mt2712_rtc, MT2712_TC_HOU, tm->tm_hour & MT2712_HOU_MASK);
+	mt2712_writel(mt2712_rtc, MT2712_TC_DOM, tm->tm_mday & MT2712_DOM_MASK);
+	mt2712_writel(mt2712_rtc, MT2712_TC_MTH,
+		      (tm->tm_mon + 1) & MT2712_MTH_MASK);
+	mt2712_writel(mt2712_rtc, MT2712_TC_YEA,
+		      (tm->tm_year - 100) & MT2712_YEA_MASK);
+
+	mt2712_rtc_write_trigger(mt2712_rtc);
+
+	if (mt2712_rtc->powerlost)
+		mt2712_rtc->powerlost = false;
+
+	return 0;
+}
+
+static int mt2712_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
+{
+	struct mt2712_rtc *mt2712_rtc = dev_get_drvdata(dev);
+	struct rtc_time *tm = &alm->time;
+	u16 irqen;
+
+	irqen = mt2712_readl(mt2712_rtc, MT2712_IRQ_EN);
+	alm->enabled = !!(irqen & MT2712_IRQ_EN_AL);
+
+	tm->tm_sec  = mt2712_readl(mt2712_rtc, MT2712_AL_SEC) & MT2712_SEC_MASK;
+	tm->tm_min  = mt2712_readl(mt2712_rtc, MT2712_AL_MIN) & MT2712_MIN_MASK;
+	tm->tm_hour = mt2712_readl(mt2712_rtc, MT2712_AL_HOU) & MT2712_HOU_MASK;
+	tm->tm_mday = mt2712_readl(mt2712_rtc, MT2712_AL_DOM) & MT2712_DOM_MASK;
+	tm->tm_mon  = (mt2712_readl(mt2712_rtc, MT2712_AL_MTH) - 1)
+		      & MT2712_MTH_MASK;
+	tm->tm_year = (mt2712_readl(mt2712_rtc, MT2712_AL_YEA) + 100)
+		      & MT2712_YEA_MASK;
+
+	return 0;
+}
+
+static int mt2712_rtc_alarm_irq_enable(struct device *dev,
+				       unsigned int enabled)
+{
+	struct mt2712_rtc *mt2712_rtc = dev_get_drvdata(dev);
+	u16 irqen;
+
+	irqen = mt2712_readl(mt2712_rtc, MT2712_IRQ_EN);
+	if (enabled)
+		irqen |= MT2712_IRQ_EN_AL;
+	else
+		irqen &= ~MT2712_IRQ_EN_AL;
+	mt2712_writel(mt2712_rtc, MT2712_IRQ_EN, irqen);
+	mt2712_rtc_write_trigger(mt2712_rtc);
+
+	return 0;
+}
+
+static int mt2712_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
+{
+	struct mt2712_rtc *mt2712_rtc = dev_get_drvdata(dev);
+	struct rtc_time *tm = &alm->time;
+
+	dev_dbg(&mt2712_rtc->rtc->dev, "set al time: %ptR, alm en: %d\n",
+		tm, alm->enabled);
+
+	mt2712_writel(mt2712_rtc, MT2712_AL_SEC,
+		      (mt2712_readl(mt2712_rtc, MT2712_AL_SEC)
+		       & ~(MT2712_SEC_MASK)) | (tm->tm_sec  & MT2712_SEC_MASK));
+	mt2712_writel(mt2712_rtc, MT2712_AL_MIN,
+		      (mt2712_readl(mt2712_rtc, MT2712_AL_MIN)
+		       & ~(MT2712_MIN_MASK)) | (tm->tm_min  & MT2712_MIN_MASK));
+	mt2712_writel(mt2712_rtc, MT2712_AL_HOU,
+		      (mt2712_readl(mt2712_rtc, MT2712_AL_HOU)
+		       & ~(MT2712_HOU_MASK)) | (tm->tm_hour & MT2712_HOU_MASK));
+	mt2712_writel(mt2712_rtc, MT2712_AL_DOM,
+		      (mt2712_readl(mt2712_rtc, MT2712_AL_DOM)
+		       & ~(MT2712_DOM_MASK)) | (tm->tm_mday & MT2712_DOM_MASK));
+	mt2712_writel(mt2712_rtc, MT2712_AL_MTH,
+		      (mt2712_readl(mt2712_rtc, MT2712_AL_MTH)
+		       & ~(MT2712_MTH_MASK))
+		      | ((tm->tm_mon + 1) & MT2712_MTH_MASK));
+	mt2712_writel(mt2712_rtc, MT2712_AL_YEA,
+		      (mt2712_readl(mt2712_rtc, MT2712_AL_YEA)
+		       & ~(MT2712_YEA_MASK))
+		      | ((tm->tm_year - 100) & MT2712_YEA_MASK));
+
+	/* mask day of week */
+	mt2712_writel(mt2712_rtc, MT2712_AL_MASK, MT2712_AL_MASK_DOW);
+	mt2712_rtc_write_trigger(mt2712_rtc);
+
+	mt2712_rtc_alarm_irq_enable(dev, alm->enabled);
+
+	return 0;
+}
+
+/* Init RTC register */
+static void mt2712_rtc_hw_init(struct mt2712_rtc *mt2712_rtc)
+{
+	u32 p1, p2;
+
+	mt2712_writel(mt2712_rtc, MT2712_BBPU,
+		      MT2712_BBPU_KEY | MT2712_BBPU_RELOAD);
+
+	mt2712_writel(mt2712_rtc, MT2712_CII_EN, 0);
+	mt2712_writel(mt2712_rtc, MT2712_AL_MASK, 0);
+	/* necessary before set MT2712_POWERKEY */
+	mt2712_writel(mt2712_rtc, MT2712_CON0, 0x4848);
+	mt2712_writel(mt2712_rtc, MT2712_CON1, 0x0048);
+
+	mt2712_rtc_write_trigger(mt2712_rtc);
+
+	p1 = mt2712_readl(mt2712_rtc, MT2712_POWERKEY1);
+	p2 = mt2712_readl(mt2712_rtc, MT2712_POWERKEY2);
+	if (p1 != MT2712_POWERKEY1_KEY || p2 != MT2712_POWERKEY2_KEY) {
+		mt2712_rtc->powerlost = true;
+		dev_dbg(&mt2712_rtc->rtc->dev,
+			"powerkey not set (lost power)\n");
+	} else {
+		mt2712_rtc->powerlost = false;
+	}
+
+	/* RTC need POWERKEY1/2 match, then goto normal work mode */
+	mt2712_writel(mt2712_rtc, MT2712_POWERKEY1, MT2712_POWERKEY1_KEY);
+	mt2712_writel(mt2712_rtc, MT2712_POWERKEY2, MT2712_POWERKEY2_KEY);
+	mt2712_rtc_write_trigger(mt2712_rtc);
+
+	mt2712_rtc_writeif_unlock(mt2712_rtc);
+}
+
+static const struct rtc_class_ops mt2712_rtc_ops = {
+	.read_time	= mt2712_rtc_read_time,
+	.set_time	= mt2712_rtc_set_time,
+	.read_alarm	= mt2712_rtc_read_alarm,
+	.set_alarm	= mt2712_rtc_set_alarm,
+	.alarm_irq_enable = mt2712_rtc_alarm_irq_enable,
+};
+
+static int mt2712_rtc_probe(struct platform_device *pdev)
+{
+	struct mt2712_rtc *mt2712_rtc;
+	int ret;
+
+	mt2712_rtc = devm_kzalloc(&pdev->dev,
+				  sizeof(struct mt2712_rtc), GFP_KERNEL);
+	if (!mt2712_rtc)
+		return -ENOMEM;
+
+	mt2712_rtc->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(mt2712_rtc->base))
+		return PTR_ERR(mt2712_rtc->base);
+
+	/* rtc hw init */
+	mt2712_rtc_hw_init(mt2712_rtc);
+
+	mt2712_rtc->irq = platform_get_irq(pdev, 0);
+	if (mt2712_rtc->irq < 0)
+		return mt2712_rtc->irq;
+
+	platform_set_drvdata(pdev, mt2712_rtc);
+
+	mt2712_rtc->rtc = devm_rtc_allocate_device(&pdev->dev);
+	if (IS_ERR(mt2712_rtc->rtc))
+		return PTR_ERR(mt2712_rtc->rtc);
+
+	ret = devm_request_threaded_irq(&pdev->dev, mt2712_rtc->irq, NULL,
+					rtc_irq_handler_thread,
+					IRQF_ONESHOT | IRQF_TRIGGER_LOW,
+					dev_name(&mt2712_rtc->rtc->dev),
+					mt2712_rtc);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n",
+			mt2712_rtc->irq, ret);
+		return ret;
+	}
+
+	device_init_wakeup(&pdev->dev, true);
+
+	mt2712_rtc->rtc->ops = &mt2712_rtc_ops;
+	mt2712_rtc->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
+	mt2712_rtc->rtc->range_max = MT2712_RTC_TIMESTAMP_END_2127;
+
+	return devm_rtc_register_device(mt2712_rtc->rtc);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int mt2712_rtc_suspend(struct device *dev)
+{
+	int wake_status = 0;
+	struct mt2712_rtc *mt2712_rtc = dev_get_drvdata(dev);
+
+	if (device_may_wakeup(dev)) {
+		wake_status = enable_irq_wake(mt2712_rtc->irq);
+		if (!wake_status)
+			mt2712_rtc->irq_wake_enabled = true;
+	}
+
+	return 0;
+}
+
+static int mt2712_rtc_resume(struct device *dev)
+{
+	int wake_status = 0;
+	struct mt2712_rtc *mt2712_rtc = dev_get_drvdata(dev);
+
+	if (device_may_wakeup(dev) && mt2712_rtc->irq_wake_enabled) {
+		wake_status = disable_irq_wake(mt2712_rtc->irq);
+		if (!wake_status)
+			mt2712_rtc->irq_wake_enabled = false;
+	}
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(mt2712_pm_ops, mt2712_rtc_suspend,
+			 mt2712_rtc_resume);
+#endif
+
+static const struct of_device_id mt2712_rtc_of_match[] = {
+	{ .compatible = "mediatek,mt2712-rtc", },
+	{ },
+};
+
+MODULE_DEVICE_TABLE(of, mt2712_rtc_of_match);
+
+static struct platform_driver mt2712_rtc_driver = {
+	.driver = {
+		.name = "mt2712-rtc",
+		.of_match_table = mt2712_rtc_of_match,
+#ifdef CONFIG_PM_SLEEP
+		.pm = &mt2712_pm_ops,
+#endif
+	},
+	.probe  = mt2712_rtc_probe,
+};
+
+module_platform_driver(mt2712_rtc_driver);
+
+MODULE_DESCRIPTION("MediaTek MT2712 SoC based RTC Driver");
+MODULE_AUTHOR("Ran Bi <ran.bi@mediatek.com>");
+MODULE_LICENSE("GPL");