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, 214 insertions, 0 deletions

diff --git a/drivers/input/touchscreen/touchit213.c b/drivers/input/touchscreen/touchit213.c
new file mode 100644
index 000000000..6d4a1acf5
--- /dev/null
+++ b/drivers/input/touchscreen/touchit213.c
@@ -0,0 +1,214 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Sahara TouchIT-213 serial touchscreen driver
+ *
+ * Copyright (c) 2007-2008 Claudio Nieder <private@claudio.ch>
+ *
+ * Based on Touchright driver (drivers/input/touchscreen/touchright.c)
+ * Copyright (c) 2006 Rick Koch <n1gp@hotmail.com>
+ * Copyright (c) 2004 Vojtech Pavlik
+ * and Dan Streetman <ddstreet@ieee.org>
+ */
+
+
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/input.h>
+#include <linux/serio.h>
+
+#define DRIVER_DESC	"Sahara TouchIT-213 serial touchscreen driver"
+
+MODULE_AUTHOR("Claudio Nieder <private@claudio.ch>");
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
+
+/*
+ * Definitions & global arrays.
+ */
+
+/*
+ * Data is received through COM1 at 9600bit/s,8bit,no parity in packets
+ * of 5 byte each.
+ *
+ *   +--------+   +--------+   +--------+   +--------+   +--------+
+ *   |1000000p|   |0xxxxxxx|   |0xxxxxxx|   |0yyyyyyy|   |0yyyyyyy|
+ *   +--------+   +--------+   +--------+   +--------+   +--------+
+ *                    MSB          LSB          MSB          LSB
+ *
+ * The value of p is 1 as long as the screen is touched and 0 when
+ * reporting the location where touching stopped, e.g. where the pen was
+ * lifted from the screen.
+ *
+ * When holding the screen in landscape mode as the BIOS text output is
+ * presented, x is the horizontal axis with values growing from left to
+ * right and y is the vertical axis with values growing from top to
+ * bottom.
+ *
+ * When holding the screen in portrait mode with the Sahara logo in its
+ * correct position, x ist the vertical axis with values growing from
+ * top to bottom and y is the horizontal axis with values growing from
+ * right to left.
+ */
+
+#define T213_FORMAT_TOUCH_BIT	0x01
+#define T213_FORMAT_STATUS_BYTE	0x80
+#define T213_FORMAT_STATUS_MASK	~T213_FORMAT_TOUCH_BIT
+
+/*
+ * On my Sahara Touch-IT 213 I have observed x values from 0 to 0x7f0
+ * and y values from 0x1d to 0x7e9, so the actual measurement is
+ * probably done with an 11 bit precision.
+ */
+#define T213_MIN_XC 0
+#define T213_MAX_XC 0x07ff
+#define T213_MIN_YC 0
+#define T213_MAX_YC 0x07ff
+
+/*
+ * Per-touchscreen data.
+ */
+
+struct touchit213 {
+	struct input_dev *dev;
+	struct serio *serio;
+	int idx;
+	unsigned char csum;
+	unsigned char data[5];
+	char phys[32];
+};
+
+static irqreturn_t touchit213_interrupt(struct serio *serio,
+		unsigned char data, unsigned int flags)
+{
+	struct touchit213 *touchit213 = serio_get_drvdata(serio);
+	struct input_dev *dev = touchit213->dev;
+
+	touchit213->data[touchit213->idx] = data;
+
+	switch (touchit213->idx++) {
+	case 0:
+		if ((touchit213->data[0] & T213_FORMAT_STATUS_MASK) !=
+				T213_FORMAT_STATUS_BYTE) {
+			pr_debug("unsynchronized data: 0x%02x\n", data);
+			touchit213->idx = 0;
+		}
+		break;
+
+	case 4:
+		touchit213->idx = 0;
+		input_report_abs(dev, ABS_X,
+			(touchit213->data[1] << 7) | touchit213->data[2]);
+		input_report_abs(dev, ABS_Y,
+			(touchit213->data[3] << 7) | touchit213->data[4]);
+		input_report_key(dev, BTN_TOUCH,
+			touchit213->data[0] & T213_FORMAT_TOUCH_BIT);
+		input_sync(dev);
+		break;
+	}
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * touchit213_disconnect() is the opposite of touchit213_connect()
+ */
+
+static void touchit213_disconnect(struct serio *serio)
+{
+	struct touchit213 *touchit213 = serio_get_drvdata(serio);
+
+	input_get_device(touchit213->dev);
+	input_unregister_device(touchit213->dev);
+	serio_close(serio);
+	serio_set_drvdata(serio, NULL);
+	input_put_device(touchit213->dev);
+	kfree(touchit213);
+}
+
+/*
+ * touchit213_connect() is the routine that is called when someone adds a
+ * new serio device that supports the Touchright protocol and registers it as
+ * an input device.
+ */
+
+static int touchit213_connect(struct serio *serio, struct serio_driver *drv)
+{
+	struct touchit213 *touchit213;
+	struct input_dev *input_dev;
+	int err;
+
+	touchit213 = kzalloc_obj(*touchit213);
+	input_dev = input_allocate_device();
+	if (!touchit213 || !input_dev) {
+		err = -ENOMEM;
+		goto fail1;
+	}
+
+	touchit213->serio = serio;
+	touchit213->dev = input_dev;
+	scnprintf(touchit213->phys, sizeof(touchit213->phys),
+		  "%s/input0", serio->phys);
+
+	input_dev->name = "Sahara Touch-iT213 Serial TouchScreen";
+	input_dev->phys = touchit213->phys;
+	input_dev->id.bustype = BUS_RS232;
+	input_dev->id.vendor = SERIO_TOUCHIT213;
+	input_dev->id.product = 0;
+	input_dev->id.version = 0x0100;
+	input_dev->dev.parent = &serio->dev;
+	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
+	input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
+	input_set_abs_params(touchit213->dev, ABS_X,
+			     T213_MIN_XC, T213_MAX_XC, 0, 0);
+	input_set_abs_params(touchit213->dev, ABS_Y,
+			     T213_MIN_YC, T213_MAX_YC, 0, 0);
+
+	serio_set_drvdata(serio, touchit213);
+
+	err = serio_open(serio, drv);
+	if (err)
+		goto fail2;
+
+	err = input_register_device(touchit213->dev);
+	if (err)
+		goto fail3;
+
+	return 0;
+
+ fail3:	serio_close(serio);
+ fail2:	serio_set_drvdata(serio, NULL);
+ fail1:	input_free_device(input_dev);
+	kfree(touchit213);
+	return err;
+}
+
+/*
+ * The serio driver structure.
+ */
+
+static const struct serio_device_id touchit213_serio_ids[] = {
+	{
+		.type	= SERIO_RS232,
+		.proto	= SERIO_TOUCHIT213,
+		.id	= SERIO_ANY,
+		.extra	= SERIO_ANY,
+	},
+	{ 0 }
+};
+
+MODULE_DEVICE_TABLE(serio, touchit213_serio_ids);
+
+static struct serio_driver touchit213_drv = {
+	.driver		= {
+		.name	= "touchit213",
+	},
+	.description	= DRIVER_DESC,
+	.id_table	= touchit213_serio_ids,
+	.interrupt	= touchit213_interrupt,
+	.connect	= touchit213_connect,
+	.disconnect	= touchit213_disconnect,
+};
+
+module_serio_driver(touchit213_drv);