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, 404 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-mxc.c b/drivers/rtc/rtc-mxc.c
new file mode 100644
index 000000000..608db97d4
--- /dev/null
+++ b/drivers/rtc/rtc-mxc.c
@@ -0,0 +1,404 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// Copyright 2004-2008 Freescale Semiconductor, Inc. All Rights Reserved.
+
+#include <linux/io.h>
+#include <linux/rtc.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/pm_wakeirq.h>
+#include <linux/clk.h>
+#include <linux/of.h>
+
+#define RTC_INPUT_CLK_32768HZ	(0x00 << 5)
+#define RTC_INPUT_CLK_32000HZ	(0x01 << 5)
+#define RTC_INPUT_CLK_38400HZ	(0x02 << 5)
+
+#define RTC_SW_BIT      (1 << 0)
+#define RTC_ALM_BIT     (1 << 2)
+#define RTC_1HZ_BIT     (1 << 4)
+#define RTC_2HZ_BIT     (1 << 7)
+#define RTC_SAM0_BIT    (1 << 8)
+#define RTC_SAM1_BIT    (1 << 9)
+#define RTC_SAM2_BIT    (1 << 10)
+#define RTC_SAM3_BIT    (1 << 11)
+#define RTC_SAM4_BIT    (1 << 12)
+#define RTC_SAM5_BIT    (1 << 13)
+#define RTC_SAM6_BIT    (1 << 14)
+#define RTC_SAM7_BIT    (1 << 15)
+#define PIT_ALL_ON      (RTC_2HZ_BIT | RTC_SAM0_BIT | RTC_SAM1_BIT | \
+			 RTC_SAM2_BIT | RTC_SAM3_BIT | RTC_SAM4_BIT | \
+			 RTC_SAM5_BIT | RTC_SAM6_BIT | RTC_SAM7_BIT)
+
+#define RTC_ENABLE_BIT  (1 << 7)
+
+#define MAX_PIE_NUM     9
+#define MAX_PIE_FREQ    512
+
+#define MXC_RTC_TIME	0
+#define MXC_RTC_ALARM	1
+
+#define RTC_HOURMIN	0x00	/*  32bit rtc hour/min counter reg */
+#define RTC_SECOND	0x04	/*  32bit rtc seconds counter reg */
+#define RTC_ALRM_HM	0x08	/*  32bit rtc alarm hour/min reg */
+#define RTC_ALRM_SEC	0x0C	/*  32bit rtc alarm seconds reg */
+#define RTC_RTCCTL	0x10	/*  32bit rtc control reg */
+#define RTC_RTCISR	0x14	/*  32bit rtc interrupt status reg */
+#define RTC_RTCIENR	0x18	/*  32bit rtc interrupt enable reg */
+#define RTC_STPWCH	0x1C	/*  32bit rtc stopwatch min reg */
+#define RTC_DAYR	0x20	/*  32bit rtc days counter reg */
+#define RTC_DAYALARM	0x24	/*  32bit rtc day alarm reg */
+#define RTC_TEST1	0x28	/*  32bit rtc test reg 1 */
+#define RTC_TEST2	0x2C	/*  32bit rtc test reg 2 */
+#define RTC_TEST3	0x30	/*  32bit rtc test reg 3 */
+
+enum imx_rtc_type {
+	IMX1_RTC,
+	IMX21_RTC,
+};
+
+struct rtc_plat_data {
+	struct rtc_device *rtc;
+	void __iomem *ioaddr;
+	int irq;
+	struct clk *clk_ref;
+	struct clk *clk_ipg;
+	struct rtc_time g_rtc_alarm;
+	enum imx_rtc_type devtype;
+};
+
+static const struct of_device_id imx_rtc_dt_ids[] = {
+	{ .compatible = "fsl,imx1-rtc", .data = (const void *)IMX1_RTC },
+	{ .compatible = "fsl,imx21-rtc", .data = (const void *)IMX21_RTC },
+	{}
+};
+MODULE_DEVICE_TABLE(of, imx_rtc_dt_ids);
+
+static inline int is_imx1_rtc(struct rtc_plat_data *data)
+{
+	return data->devtype == IMX1_RTC;
+}
+
+/*
+ * This function is used to obtain the RTC time or the alarm value in
+ * second.
+ */
+static time64_t get_alarm_or_time(struct device *dev, int time_alarm)
+{
+	struct rtc_plat_data *pdata = dev_get_drvdata(dev);
+	void __iomem *ioaddr = pdata->ioaddr;
+	u32 day = 0, hr = 0, min = 0, sec = 0, hr_min = 0;
+
+	switch (time_alarm) {
+	case MXC_RTC_TIME:
+		day = readw(ioaddr + RTC_DAYR);
+		hr_min = readw(ioaddr + RTC_HOURMIN);
+		sec = readw(ioaddr + RTC_SECOND);
+		break;
+	case MXC_RTC_ALARM:
+		day = readw(ioaddr + RTC_DAYALARM);
+		hr_min = readw(ioaddr + RTC_ALRM_HM) & 0xffff;
+		sec = readw(ioaddr + RTC_ALRM_SEC);
+		break;
+	}
+
+	hr = hr_min >> 8;
+	min = hr_min & 0xff;
+
+	return ((((time64_t)day * 24 + hr) * 60) + min) * 60 + sec;
+}
+
+/*
+ * This function sets the RTC alarm value or the time value.
+ */
+static void set_alarm_or_time(struct device *dev, int time_alarm, time64_t time)
+{
+	u32 tod, day, hr, min, sec, temp;
+	struct rtc_plat_data *pdata = dev_get_drvdata(dev);
+	void __iomem *ioaddr = pdata->ioaddr;
+
+	day = div_s64_rem(time, 86400, &tod);
+
+	/* time is within a day now */
+	hr = tod / 3600;
+	tod -= hr * 3600;
+
+	/* time is within an hour now */
+	min = tod / 60;
+	sec = tod - min * 60;
+
+	temp = (hr << 8) + min;
+
+	switch (time_alarm) {
+	case MXC_RTC_TIME:
+		writew(day, ioaddr + RTC_DAYR);
+		writew(sec, ioaddr + RTC_SECOND);
+		writew(temp, ioaddr + RTC_HOURMIN);
+		break;
+	case MXC_RTC_ALARM:
+		writew(day, ioaddr + RTC_DAYALARM);
+		writew(sec, ioaddr + RTC_ALRM_SEC);
+		writew(temp, ioaddr + RTC_ALRM_HM);
+		break;
+	}
+}
+
+/*
+ * This function updates the RTC alarm registers and then clears all the
+ * interrupt status bits.
+ */
+static void rtc_update_alarm(struct device *dev, struct rtc_time *alrm)
+{
+	time64_t time;
+	struct rtc_plat_data *pdata = dev_get_drvdata(dev);
+	void __iomem *ioaddr = pdata->ioaddr;
+
+	time = rtc_tm_to_time64(alrm);
+
+	/* clear all the interrupt status bits */
+	writew(readw(ioaddr + RTC_RTCISR), ioaddr + RTC_RTCISR);
+	set_alarm_or_time(dev, MXC_RTC_ALARM, time);
+}
+
+static void mxc_rtc_irq_enable(struct device *dev, unsigned int bit,
+				unsigned int enabled)
+{
+	struct rtc_plat_data *pdata = dev_get_drvdata(dev);
+	void __iomem *ioaddr = pdata->ioaddr;
+	u32 reg;
+	unsigned long flags;
+
+	spin_lock_irqsave(&pdata->rtc->irq_lock, flags);
+	reg = readw(ioaddr + RTC_RTCIENR);
+
+	if (enabled)
+		reg |= bit;
+	else
+		reg &= ~bit;
+
+	writew(reg, ioaddr + RTC_RTCIENR);
+	spin_unlock_irqrestore(&pdata->rtc->irq_lock, flags);
+}
+
+/* This function is the RTC interrupt service routine. */
+static irqreturn_t mxc_rtc_interrupt(int irq, void *dev_id)
+{
+	struct platform_device *pdev = dev_id;
+	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
+	void __iomem *ioaddr = pdata->ioaddr;
+	u32 status;
+	u32 events = 0;
+
+	spin_lock(&pdata->rtc->irq_lock);
+	status = readw(ioaddr + RTC_RTCISR) & readw(ioaddr + RTC_RTCIENR);
+	/* clear interrupt sources */
+	writew(status, ioaddr + RTC_RTCISR);
+
+	/* update irq data & counter */
+	if (status & RTC_ALM_BIT) {
+		events |= (RTC_AF | RTC_IRQF);
+		/* RTC alarm should be one-shot */
+		mxc_rtc_irq_enable(&pdev->dev, RTC_ALM_BIT, 0);
+	}
+
+	if (status & PIT_ALL_ON)
+		events |= (RTC_PF | RTC_IRQF);
+
+	rtc_update_irq(pdata->rtc, 1, events);
+	spin_unlock(&pdata->rtc->irq_lock);
+
+	return IRQ_HANDLED;
+}
+
+static int mxc_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+	mxc_rtc_irq_enable(dev, RTC_ALM_BIT, enabled);
+	return 0;
+}
+
+/*
+ * This function reads the current RTC time into tm in Gregorian date.
+ */
+static int mxc_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+	time64_t val;
+
+	/* Avoid roll-over from reading the different registers */
+	do {
+		val = get_alarm_or_time(dev, MXC_RTC_TIME);
+	} while (val != get_alarm_or_time(dev, MXC_RTC_TIME));
+
+	rtc_time64_to_tm(val, tm);
+
+	return 0;
+}
+
+/*
+ * This function sets the internal RTC time based on tm in Gregorian date.
+ */
+static int mxc_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+	time64_t time = rtc_tm_to_time64(tm);
+
+	/* Avoid roll-over from reading the different registers */
+	do {
+		set_alarm_or_time(dev, MXC_RTC_TIME, time);
+	} while (time != get_alarm_or_time(dev, MXC_RTC_TIME));
+
+	return 0;
+}
+
+/*
+ * This function reads the current alarm value into the passed in 'alrm'
+ * argument. It updates the alrm's pending field value based on the whether
+ * an alarm interrupt occurs or not.
+ */
+static int mxc_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct rtc_plat_data *pdata = dev_get_drvdata(dev);
+	void __iomem *ioaddr = pdata->ioaddr;
+
+	rtc_time64_to_tm(get_alarm_or_time(dev, MXC_RTC_ALARM), &alrm->time);
+	alrm->pending = ((readw(ioaddr + RTC_RTCISR) & RTC_ALM_BIT)) ? 1 : 0;
+
+	return 0;
+}
+
+/*
+ * This function sets the RTC alarm based on passed in alrm.
+ */
+static int mxc_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct rtc_plat_data *pdata = dev_get_drvdata(dev);
+
+	rtc_update_alarm(dev, &alrm->time);
+
+	memcpy(&pdata->g_rtc_alarm, &alrm->time, sizeof(struct rtc_time));
+	mxc_rtc_irq_enable(dev, RTC_ALM_BIT, alrm->enabled);
+
+	return 0;
+}
+
+/* RTC layer */
+static const struct rtc_class_ops mxc_rtc_ops = {
+	.read_time		= mxc_rtc_read_time,
+	.set_time		= mxc_rtc_set_time,
+	.read_alarm		= mxc_rtc_read_alarm,
+	.set_alarm		= mxc_rtc_set_alarm,
+	.alarm_irq_enable	= mxc_rtc_alarm_irq_enable,
+};
+
+static int mxc_rtc_probe(struct platform_device *pdev)
+{
+	struct rtc_device *rtc;
+	struct rtc_plat_data *pdata = NULL;
+	u32 reg;
+	unsigned long rate;
+	int ret;
+
+	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+	if (!pdata)
+		return -ENOMEM;
+
+	pdata->devtype = (uintptr_t)of_device_get_match_data(&pdev->dev);
+
+	pdata->ioaddr = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(pdata->ioaddr))
+		return PTR_ERR(pdata->ioaddr);
+
+	rtc = devm_rtc_allocate_device(&pdev->dev);
+	if (IS_ERR(rtc))
+		return PTR_ERR(rtc);
+
+	pdata->rtc = rtc;
+	rtc->ops = &mxc_rtc_ops;
+	if (is_imx1_rtc(pdata)) {
+		struct rtc_time tm;
+
+		/* 9bit days + hours minutes seconds */
+		rtc->range_max = (1 << 9) * 86400 - 1;
+
+		/*
+		 * Set the start date as beginning of the current year. This can
+		 * be overridden using device tree.
+		 */
+		rtc_time64_to_tm(ktime_get_real_seconds(), &tm);
+		rtc->start_secs =  mktime64(tm.tm_year, 1, 1, 0, 0, 0);
+		rtc->set_start_time = true;
+	} else {
+		/* 16bit days + hours minutes seconds */
+		rtc->range_max = (1 << 16) * 86400ULL - 1;
+	}
+
+	pdata->clk_ipg = devm_clk_get_enabled(&pdev->dev, "ipg");
+	if (IS_ERR(pdata->clk_ipg)) {
+		dev_err(&pdev->dev, "unable to get ipg clock!\n");
+		return PTR_ERR(pdata->clk_ipg);
+	}
+
+	pdata->clk_ref = devm_clk_get_enabled(&pdev->dev, "ref");
+	if (IS_ERR(pdata->clk_ref)) {
+		dev_err(&pdev->dev, "unable to get ref clock!\n");
+		return PTR_ERR(pdata->clk_ref);
+	}
+
+	rate = clk_get_rate(pdata->clk_ref);
+
+	if (rate == 32768)
+		reg = RTC_INPUT_CLK_32768HZ;
+	else if (rate == 32000)
+		reg = RTC_INPUT_CLK_32000HZ;
+	else if (rate == 38400)
+		reg = RTC_INPUT_CLK_38400HZ;
+	else {
+		dev_err(&pdev->dev, "rtc clock is not valid (%lu)\n", rate);
+		return -EINVAL;
+	}
+
+	reg |= RTC_ENABLE_BIT;
+	writew(reg, (pdata->ioaddr + RTC_RTCCTL));
+	if (((readw(pdata->ioaddr + RTC_RTCCTL)) & RTC_ENABLE_BIT) == 0) {
+		dev_err(&pdev->dev, "hardware module can't be enabled!\n");
+		return -EIO;
+	}
+
+	platform_set_drvdata(pdev, pdata);
+
+	/* Configure and enable the RTC */
+	pdata->irq = platform_get_irq(pdev, 0);
+
+	if (pdata->irq >= 0 &&
+	    devm_request_irq(&pdev->dev, pdata->irq, mxc_rtc_interrupt,
+			     IRQF_SHARED, pdev->name, pdev) < 0) {
+		dev_warn(&pdev->dev, "interrupt not available.\n");
+		pdata->irq = -1;
+	}
+
+	if (pdata->irq >= 0) {
+		device_init_wakeup(&pdev->dev, true);
+		ret = dev_pm_set_wake_irq(&pdev->dev, pdata->irq);
+		if (ret)
+			dev_err(&pdev->dev, "failed to enable irq wake\n");
+	}
+
+	ret = devm_rtc_register_device(rtc);
+
+	return ret;
+}
+
+static struct platform_driver mxc_rtc_driver = {
+	.driver = {
+		   .name	= "mxc_rtc",
+		   .of_match_table = imx_rtc_dt_ids,
+	},
+	.probe = mxc_rtc_probe,
+};
+
+module_platform_driver(mxc_rtc_driver)
+
+MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
+MODULE_DESCRIPTION("RTC driver for Freescale MXC");
+MODULE_LICENSE("GPL");
+