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, 228 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-msm6242.c b/drivers/rtc/rtc-msm6242.c
new file mode 100644
index 000000000..80e364baa
--- /dev/null
+++ b/drivers/rtc/rtc-msm6242.c
@@ -0,0 +1,228 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *  Oki MSM6242 RTC Driver
+ *
+ *  Copyright 2009 Geert Uytterhoeven
+ *
+ *  Based on the A2000 TOD code in arch/m68k/amiga/config.c
+ *  Copyright (C) 1993 Hamish Macdonald
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+#include <linux/slab.h>
+
+
+enum {
+	MSM6242_SECOND1		= 0x0,	/* 1-second digit register */
+	MSM6242_SECOND10	= 0x1,	/* 10-second digit register */
+	MSM6242_MINUTE1		= 0x2,	/* 1-minute digit register */
+	MSM6242_MINUTE10	= 0x3,	/* 10-minute digit register */
+	MSM6242_HOUR1		= 0x4,	/* 1-hour digit register */
+	MSM6242_HOUR10		= 0x5,	/* PM/AM, 10-hour digit register */
+	MSM6242_DAY1		= 0x6,	/* 1-day digit register */
+	MSM6242_DAY10		= 0x7,	/* 10-day digit register */
+	MSM6242_MONTH1		= 0x8,	/* 1-month digit register */
+	MSM6242_MONTH10		= 0x9,	/* 10-month digit register */
+	MSM6242_YEAR1		= 0xa,	/* 1-year digit register */
+	MSM6242_YEAR10		= 0xb,	/* 10-year digit register */
+	MSM6242_WEEK		= 0xc,	/* Week register */
+	MSM6242_CD		= 0xd,	/* Control Register D */
+	MSM6242_CE		= 0xe,	/* Control Register E */
+	MSM6242_CF		= 0xf,	/* Control Register F */
+};
+
+#define MSM6242_HOUR10_AM	(0 << 2)
+#define MSM6242_HOUR10_PM	(1 << 2)
+#define MSM6242_HOUR10_HR_MASK	(3 << 0)
+
+#define MSM6242_WEEK_SUNDAY	0
+#define MSM6242_WEEK_MONDAY	1
+#define MSM6242_WEEK_TUESDAY	2
+#define MSM6242_WEEK_WEDNESDAY	3
+#define MSM6242_WEEK_THURSDAY	4
+#define MSM6242_WEEK_FRIDAY	5
+#define MSM6242_WEEK_SATURDAY	6
+
+#define MSM6242_CD_30_S_ADJ	(1 << 3)	/* 30-second adjustment */
+#define MSM6242_CD_IRQ_FLAG	(1 << 2)
+#define MSM6242_CD_BUSY		(1 << 1)
+#define MSM6242_CD_HOLD		(1 << 0)
+
+#define MSM6242_CE_T_MASK	(3 << 2)
+#define MSM6242_CE_T_64HZ	(0 << 2)	/* period 1/64 second */
+#define MSM6242_CE_T_1HZ	(1 << 2)	/* period 1 second */
+#define MSM6242_CE_T_1MINUTE	(2 << 2)	/* period 1 minute */
+#define MSM6242_CE_T_1HOUR	(3 << 2)	/* period 1 hour */
+
+#define MSM6242_CE_ITRPT_STND	(1 << 1)
+#define MSM6242_CE_MASK		(1 << 0)	/* STD.P output control */
+
+#define MSM6242_CF_TEST		(1 << 3)
+#define MSM6242_CF_12H		(0 << 2)
+#define MSM6242_CF_24H		(1 << 2)
+#define MSM6242_CF_STOP		(1 << 1)
+#define MSM6242_CF_REST		(1 << 0)	/* reset */
+
+
+struct msm6242_priv {
+	u32 __iomem *regs;
+	struct rtc_device *rtc;
+};
+
+static inline unsigned int msm6242_read(struct msm6242_priv *priv,
+				       unsigned int reg)
+{
+	return __raw_readl(&priv->regs[reg]) & 0xf;
+}
+
+static inline void msm6242_write(struct msm6242_priv *priv, unsigned int val,
+				unsigned int reg)
+{
+	__raw_writel(val, &priv->regs[reg]);
+}
+
+static void msm6242_lock(struct msm6242_priv *priv)
+{
+	int cnt = 5;
+
+	msm6242_write(priv, MSM6242_CD_HOLD|MSM6242_CD_IRQ_FLAG, MSM6242_CD);
+
+	while ((msm6242_read(priv, MSM6242_CD) & MSM6242_CD_BUSY) && cnt) {
+		msm6242_write(priv, MSM6242_CD_IRQ_FLAG, MSM6242_CD);
+		udelay(70);
+		msm6242_write(priv, MSM6242_CD_HOLD|MSM6242_CD_IRQ_FLAG, MSM6242_CD);
+		cnt--;
+	}
+
+	if (!cnt)
+		pr_warn("timed out waiting for RTC (0x%x)\n",
+			msm6242_read(priv, MSM6242_CD));
+}
+
+static void msm6242_unlock(struct msm6242_priv *priv)
+{
+	msm6242_write(priv, MSM6242_CD_IRQ_FLAG, MSM6242_CD);
+}
+
+static int msm6242_read_time(struct device *dev, struct rtc_time *tm)
+{
+	struct msm6242_priv *priv = dev_get_drvdata(dev);
+
+	msm6242_lock(priv);
+
+	tm->tm_sec  = msm6242_read(priv, MSM6242_SECOND10) * 10 +
+		      msm6242_read(priv, MSM6242_SECOND1);
+	tm->tm_min  = msm6242_read(priv, MSM6242_MINUTE10) * 10 +
+		      msm6242_read(priv, MSM6242_MINUTE1);
+	tm->tm_hour = (msm6242_read(priv, MSM6242_HOUR10) &
+		       MSM6242_HOUR10_HR_MASK) * 10 +
+		      msm6242_read(priv, MSM6242_HOUR1);
+	tm->tm_mday = msm6242_read(priv, MSM6242_DAY10) * 10 +
+		      msm6242_read(priv, MSM6242_DAY1);
+	tm->tm_wday = msm6242_read(priv, MSM6242_WEEK);
+	tm->tm_mon  = msm6242_read(priv, MSM6242_MONTH10) * 10 +
+		      msm6242_read(priv, MSM6242_MONTH1) - 1;
+	tm->tm_year = msm6242_read(priv, MSM6242_YEAR10) * 10 +
+		      msm6242_read(priv, MSM6242_YEAR1);
+	if (tm->tm_year <= 69)
+		tm->tm_year += 100;
+
+	if (!(msm6242_read(priv, MSM6242_CF) & MSM6242_CF_24H)) {
+		unsigned int pm = msm6242_read(priv, MSM6242_HOUR10) &
+				  MSM6242_HOUR10_PM;
+		if (!pm && tm->tm_hour == 12)
+			tm->tm_hour = 0;
+		else if (pm && tm->tm_hour != 12)
+			tm->tm_hour += 12;
+	}
+
+	msm6242_unlock(priv);
+
+	return 0;
+}
+
+static int msm6242_set_time(struct device *dev, struct rtc_time *tm)
+{
+	struct msm6242_priv *priv = dev_get_drvdata(dev);
+
+	msm6242_lock(priv);
+
+	msm6242_write(priv, tm->tm_sec / 10, MSM6242_SECOND10);
+	msm6242_write(priv, tm->tm_sec % 10, MSM6242_SECOND1);
+	msm6242_write(priv, tm->tm_min / 10, MSM6242_MINUTE10);
+	msm6242_write(priv, tm->tm_min % 10, MSM6242_MINUTE1);
+	if (msm6242_read(priv, MSM6242_CF) & MSM6242_CF_24H)
+		msm6242_write(priv, tm->tm_hour / 10, MSM6242_HOUR10);
+	else if (tm->tm_hour >= 12)
+		msm6242_write(priv, MSM6242_HOUR10_PM + (tm->tm_hour - 12) / 10,
+			      MSM6242_HOUR10);
+	else
+		msm6242_write(priv, tm->tm_hour / 10, MSM6242_HOUR10);
+	msm6242_write(priv, tm->tm_hour % 10, MSM6242_HOUR1);
+	msm6242_write(priv, tm->tm_mday / 10, MSM6242_DAY10);
+	msm6242_write(priv, tm->tm_mday % 10, MSM6242_DAY1);
+	if (tm->tm_wday != -1)
+		msm6242_write(priv, tm->tm_wday, MSM6242_WEEK);
+	msm6242_write(priv, (tm->tm_mon + 1) / 10, MSM6242_MONTH10);
+	msm6242_write(priv, (tm->tm_mon + 1) % 10, MSM6242_MONTH1);
+	if (tm->tm_year >= 100)
+		tm->tm_year -= 100;
+	msm6242_write(priv, tm->tm_year / 10, MSM6242_YEAR10);
+	msm6242_write(priv, tm->tm_year % 10, MSM6242_YEAR1);
+
+	msm6242_unlock(priv);
+	return 0;
+}
+
+static const struct rtc_class_ops msm6242_rtc_ops = {
+	.read_time	= msm6242_read_time,
+	.set_time	= msm6242_set_time,
+};
+
+static int __init msm6242_rtc_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	struct msm6242_priv *priv;
+	struct rtc_device *rtc;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENODEV;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->regs = devm_ioremap(&pdev->dev, res->start, resource_size(res));
+	if (!priv->regs)
+		return -ENOMEM;
+	platform_set_drvdata(pdev, priv);
+
+	rtc = devm_rtc_device_register(&pdev->dev, "rtc-msm6242",
+				&msm6242_rtc_ops, THIS_MODULE);
+	if (IS_ERR(rtc))
+		return PTR_ERR(rtc);
+
+	priv->rtc = rtc;
+	return 0;
+}
+
+static struct platform_driver msm6242_rtc_driver = {
+	.driver	= {
+		.name	= "rtc-msm6242",
+	},
+};
+
+module_platform_driver_probe(msm6242_rtc_driver, msm6242_rtc_probe);
+
+MODULE_AUTHOR("Geert Uytterhoeven <geert@linux-m68k.org>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Oki MSM6242 RTC driver");
+MODULE_ALIAS("platform:rtc-msm6242");