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, 468 insertions, 0 deletions

diff --git a/drivers/input/mouse/vmmouse.c b/drivers/input/mouse/vmmouse.c
new file mode 100644
index 000000000..aaecdd3d5
--- /dev/null
+++ b/drivers/input/mouse/vmmouse.c
@@ -0,0 +1,468 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Driver for Virtual PS/2 Mouse on VMware and QEMU hypervisors.
+ *
+ * Copyright (C) 2014, VMware, Inc. All Rights Reserved.
+ *
+ * Twin device code is hugely inspired by the ALPS driver.
+ * Authors:
+ *   Dmitry Torokhov <dmitry.torokhov@gmail.com>
+ *   Thomas Hellstrom <thellstrom@vmware.com>
+ */
+
+#include <linux/input.h>
+#include <linux/serio.h>
+#include <linux/libps2.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <asm/hypervisor.h>
+#include <asm/vmware.h>
+
+#include "psmouse.h"
+#include "vmmouse.h"
+
+/*
+ * Main commands supported by the vmmouse hypervisor port.
+ */
+#define VMWARE_CMD_ABSPOINTER_DATA	39
+#define VMWARE_CMD_ABSPOINTER_STATUS	40
+#define VMWARE_CMD_ABSPOINTER_COMMAND	41
+#define VMWARE_CMD_ABSPOINTER_RESTRICT	86
+
+/*
+ * Subcommands for VMWARE_CMD_ABSPOINTER_COMMAND
+ */
+#define VMMOUSE_CMD_ENABLE			0x45414552U
+#define VMMOUSE_CMD_DISABLE			0x000000f5U
+#define VMMOUSE_CMD_REQUEST_RELATIVE		0x4c455252U
+#define VMMOUSE_CMD_REQUEST_ABSOLUTE		0x53424152U
+
+#define VMMOUSE_ERROR				0xffff0000U
+
+#define VMMOUSE_VERSION_ID			0x3442554aU
+
+#define VMMOUSE_RELATIVE_PACKET			0x00010000U
+
+#define VMMOUSE_LEFT_BUTTON			0x20
+#define VMMOUSE_RIGHT_BUTTON			0x10
+#define VMMOUSE_MIDDLE_BUTTON			0x08
+
+/*
+ * VMMouse Restrict command
+ */
+#define VMMOUSE_RESTRICT_ANY                    0x00
+#define VMMOUSE_RESTRICT_CPL0                   0x01
+#define VMMOUSE_RESTRICT_IOPL                   0x02
+
+#define VMMOUSE_MAX_X                           0xFFFF
+#define VMMOUSE_MAX_Y                           0xFFFF
+
+#define VMMOUSE_VENDOR "VMware"
+#define VMMOUSE_NAME   "VMMouse"
+
+/**
+ * struct vmmouse_data - private data structure for the vmmouse driver
+ *
+ * @abs_dev: "Absolute" device used to report absolute mouse movement.
+ * @phys: Physical path for the absolute device.
+ * @dev_name: Name attribute name for the absolute device.
+ */
+struct vmmouse_data {
+	struct input_dev *abs_dev;
+	char phys[32];
+	char dev_name[128];
+};
+
+/**
+ * vmmouse_report_button - report button state on the correct input device
+ *
+ * @psmouse:  Pointer to the psmouse struct
+ * @abs_dev:  The absolute input device
+ * @rel_dev:  The relative input device
+ * @pref_dev: The preferred device for reporting
+ * @code:     Button code
+ * @value:    Button value
+ *
+ * Report @value and @code on @pref_dev, unless the button is already
+ * pressed on the other device, in which case the state is reported on that
+ * device.
+ */
+static void vmmouse_report_button(struct psmouse *psmouse,
+				  struct input_dev *abs_dev,
+				  struct input_dev *rel_dev,
+				  struct input_dev *pref_dev,
+				  unsigned int code, int value)
+{
+	if (test_bit(code, abs_dev->key))
+		pref_dev = abs_dev;
+	else if (test_bit(code, rel_dev->key))
+		pref_dev = rel_dev;
+
+	input_report_key(pref_dev, code, value);
+}
+
+/**
+ * vmmouse_report_events - process events on the vmmouse communications channel
+ *
+ * @psmouse: Pointer to the psmouse struct
+ *
+ * This function pulls events from the vmmouse communications channel and
+ * reports them on the correct (absolute or relative) input device. When the
+ * communications channel is drained, or if we've processed more than 255
+ * psmouse commands, the function returns PSMOUSE_FULL_PACKET. If there is a
+ * host- or synchronization error, the function returns PSMOUSE_BAD_DATA in
+ * the hope that the caller will reset the communications channel.
+ */
+static psmouse_ret_t vmmouse_report_events(struct psmouse *psmouse)
+{
+	struct input_dev *rel_dev = psmouse->dev;
+	struct vmmouse_data *priv = psmouse->private;
+	struct input_dev *abs_dev = priv->abs_dev;
+	struct input_dev *pref_dev;
+	u32 status, x, y, z;
+	unsigned int queue_length;
+	unsigned int count = 255;
+
+	while (count--) {
+		/* See if we have motion data. */
+		status = vmware_hypercall1(VMWARE_CMD_ABSPOINTER_STATUS, 0);
+		if ((status & VMMOUSE_ERROR) == VMMOUSE_ERROR) {
+			psmouse_err(psmouse, "failed to fetch status data\n");
+			/*
+			 * After a few attempts this will result in
+			 * reconnect.
+			 */
+			return PSMOUSE_BAD_DATA;
+		}
+
+		queue_length = status & 0xffff;
+		if (queue_length == 0)
+			break;
+
+		if (queue_length % 4) {
+			psmouse_err(psmouse, "invalid queue length\n");
+			return PSMOUSE_BAD_DATA;
+		}
+
+		/* Now get it */
+		status = vmware_hypercall4(VMWARE_CMD_ABSPOINTER_DATA, 4,
+					   &x, &y, &z);
+
+		/*
+		 * And report what we've got. Prefer to report button
+		 * events on the same device where we report motion events.
+		 * This doesn't work well with the mouse wheel, though. See
+		 * below. Ideally we would want to report that on the
+		 * preferred device as well.
+		 */
+		if (status & VMMOUSE_RELATIVE_PACKET) {
+			pref_dev = rel_dev;
+			input_report_rel(rel_dev, REL_X, (s32)x);
+			input_report_rel(rel_dev, REL_Y, -(s32)y);
+		} else {
+			pref_dev = abs_dev;
+			input_report_abs(abs_dev, ABS_X, x);
+			input_report_abs(abs_dev, ABS_Y, y);
+		}
+
+		/* Xorg seems to ignore wheel events on absolute devices */
+		input_report_rel(rel_dev, REL_WHEEL, -(s8)((u8) z));
+
+		vmmouse_report_button(psmouse, abs_dev, rel_dev,
+				      pref_dev, BTN_LEFT,
+				      status & VMMOUSE_LEFT_BUTTON);
+		vmmouse_report_button(psmouse, abs_dev, rel_dev,
+				      pref_dev, BTN_RIGHT,
+				      status & VMMOUSE_RIGHT_BUTTON);
+		vmmouse_report_button(psmouse, abs_dev, rel_dev,
+				      pref_dev, BTN_MIDDLE,
+				      status & VMMOUSE_MIDDLE_BUTTON);
+		input_sync(abs_dev);
+		input_sync(rel_dev);
+	}
+
+	return PSMOUSE_FULL_PACKET;
+}
+
+/**
+ * vmmouse_process_byte - process data on the ps/2 channel
+ *
+ * @psmouse: Pointer to the psmouse struct
+ *
+ * When the ps/2 channel indicates that there is vmmouse data available,
+ * call vmmouse channel processing. Otherwise, continue to accept bytes. If
+ * there is a synchronization or communication data error, return
+ * PSMOUSE_BAD_DATA in the hope that the caller will reset the mouse.
+ */
+static psmouse_ret_t vmmouse_process_byte(struct psmouse *psmouse)
+{
+	unsigned char *packet = psmouse->packet;
+
+	switch (psmouse->pktcnt) {
+	case 1:
+		return (packet[0] & 0x8) == 0x8 ?
+			PSMOUSE_GOOD_DATA : PSMOUSE_BAD_DATA;
+
+	case 2:
+		return PSMOUSE_GOOD_DATA;
+
+	default:
+		return vmmouse_report_events(psmouse);
+	}
+}
+
+/**
+ * vmmouse_disable - Disable vmmouse
+ *
+ * @psmouse: Pointer to the psmouse struct
+ *
+ * Tries to disable vmmouse mode.
+ */
+static void vmmouse_disable(struct psmouse *psmouse)
+{
+	u32 status;
+
+	vmware_hypercall1(VMWARE_CMD_ABSPOINTER_COMMAND, VMMOUSE_CMD_DISABLE);
+
+	status = vmware_hypercall1(VMWARE_CMD_ABSPOINTER_STATUS, 0);
+	if ((status & VMMOUSE_ERROR) != VMMOUSE_ERROR)
+		psmouse_warn(psmouse, "failed to disable vmmouse device\n");
+}
+
+/**
+ * vmmouse_enable - Enable vmmouse and request absolute mode.
+ *
+ * @psmouse: Pointer to the psmouse struct
+ *
+ * Tries to enable vmmouse mode. Performs basic checks and requests
+ * absolute vmmouse mode.
+ * Returns 0 on success, -ENODEV on failure.
+ */
+static int vmmouse_enable(struct psmouse *psmouse)
+{
+	u32 status, version;
+
+	/*
+	 * Try enabling the device. If successful, we should be able to
+	 * read valid version ID back from it.
+	 */
+	vmware_hypercall1(VMWARE_CMD_ABSPOINTER_COMMAND, VMMOUSE_CMD_ENABLE);
+
+	/*
+	 * See if version ID can be retrieved.
+	 */
+	status = vmware_hypercall1(VMWARE_CMD_ABSPOINTER_STATUS, 0);
+	if ((status & 0x0000ffff) == 0) {
+		psmouse_dbg(psmouse, "empty flags - assuming no device\n");
+		return -ENXIO;
+	}
+
+	version = vmware_hypercall1(VMWARE_CMD_ABSPOINTER_DATA,
+				    1 /* single item */);
+	if (version != VMMOUSE_VERSION_ID) {
+		psmouse_dbg(psmouse, "Unexpected version value: %u vs %u\n",
+			    (unsigned) version, VMMOUSE_VERSION_ID);
+		vmmouse_disable(psmouse);
+		return -ENXIO;
+	}
+
+	/*
+	 * Restrict ioport access, if possible.
+	 */
+	vmware_hypercall1(VMWARE_CMD_ABSPOINTER_RESTRICT,
+			  VMMOUSE_RESTRICT_CPL0);
+
+	vmware_hypercall1(VMWARE_CMD_ABSPOINTER_COMMAND,
+			  VMMOUSE_CMD_REQUEST_ABSOLUTE);
+
+	return 0;
+}
+
+/*
+ * Array of supported hypervisors.
+ */
+static enum x86_hypervisor_type vmmouse_supported_hypervisors[] = {
+	X86_HYPER_VMWARE,
+	X86_HYPER_KVM,
+};
+
+/**
+ * vmmouse_check_hypervisor - Check if we're running on a supported hypervisor
+ */
+static bool vmmouse_check_hypervisor(void)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(vmmouse_supported_hypervisors); i++)
+		if (vmmouse_supported_hypervisors[i] == x86_hyper_type)
+			return true;
+
+	return false;
+}
+
+/**
+ * vmmouse_detect - Probe whether vmmouse is available
+ *
+ * @psmouse: Pointer to the psmouse struct
+ * @set_properties: Whether to set psmouse name and vendor
+ *
+ * Returns 0 if vmmouse channel is available. Negative error code if not.
+ */
+int vmmouse_detect(struct psmouse *psmouse, bool set_properties)
+{
+	u32 response, version, type;
+
+	if (!vmmouse_check_hypervisor()) {
+		psmouse_dbg(psmouse,
+			    "VMMouse not running on supported hypervisor.\n");
+		return -ENXIO;
+	}
+
+	/* Check if the device is present */
+	response = ~VMWARE_HYPERVISOR_MAGIC;
+	version = vmware_hypercall3(VMWARE_CMD_GETVERSION, 0, &response, &type);
+	if (response != VMWARE_HYPERVISOR_MAGIC || version == 0xffffffffU)
+		return -ENXIO;
+
+	if (set_properties) {
+		psmouse->vendor = VMMOUSE_VENDOR;
+		psmouse->name = VMMOUSE_NAME;
+		psmouse->model = version;
+	}
+
+	return 0;
+}
+
+/**
+ * vmmouse_reset - Disable vmmouse and reset
+ *
+ * @psmouse: Pointer to the psmouse struct
+ *
+ * Tries to disable vmmouse mode before enter suspend.
+ */
+static void vmmouse_reset(struct psmouse *psmouse)
+{
+	vmmouse_disable(psmouse);
+	psmouse_reset(psmouse);
+}
+
+/**
+ * vmmouse_disconnect - Take down vmmouse driver
+ *
+ * @psmouse: Pointer to the psmouse struct
+ *
+ * Takes down vmmouse driver and frees resources set up in vmmouse_init().
+ */
+static void vmmouse_disconnect(struct psmouse *psmouse)
+{
+	struct vmmouse_data *priv = psmouse->private;
+
+	vmmouse_disable(psmouse);
+	psmouse_reset(psmouse);
+	input_unregister_device(priv->abs_dev);
+	kfree(priv);
+}
+
+/**
+ * vmmouse_reconnect - Reset the ps/2 - and vmmouse connections
+ *
+ * @psmouse: Pointer to the psmouse struct
+ *
+ * Attempts to reset the mouse connections. Returns 0 on success and
+ * -1 on failure.
+ */
+static int vmmouse_reconnect(struct psmouse *psmouse)
+{
+	int error;
+
+	psmouse_reset(psmouse);
+	vmmouse_disable(psmouse);
+	error = vmmouse_enable(psmouse);
+	if (error) {
+		psmouse_err(psmouse,
+			    "Unable to re-enable mouse when reconnecting, err: %d\n",
+			    error);
+		return error;
+	}
+
+	return 0;
+}
+
+/**
+ * vmmouse_init - Initialize the vmmouse driver
+ *
+ * @psmouse: Pointer to the psmouse struct
+ *
+ * Requests the device and tries to enable vmmouse mode.
+ * If successful, sets up the input device for relative movement events.
+ * It also allocates another input device and sets it up for absolute motion
+ * events. Returns 0 on success and -1 on failure.
+ */
+int vmmouse_init(struct psmouse *psmouse)
+{
+	struct vmmouse_data *priv;
+	struct input_dev *rel_dev = psmouse->dev, *abs_dev;
+	int error;
+
+	psmouse_reset(psmouse);
+	error = vmmouse_enable(psmouse);
+	if (error)
+		return error;
+
+	priv = kzalloc_obj(*priv);
+	abs_dev = input_allocate_device();
+	if (!priv || !abs_dev) {
+		error = -ENOMEM;
+		goto init_fail;
+	}
+
+	priv->abs_dev = abs_dev;
+	psmouse->private = priv;
+
+	/* Set up and register absolute device */
+	snprintf(priv->phys, sizeof(priv->phys), "%s/input1",
+		 psmouse->ps2dev.serio->phys);
+
+	/* Mimic name setup for relative device in psmouse-base.c */
+	snprintf(priv->dev_name, sizeof(priv->dev_name), "%s %s %s",
+		 VMMOUSE_PSNAME, VMMOUSE_VENDOR, VMMOUSE_NAME);
+	abs_dev->phys = priv->phys;
+	abs_dev->name = priv->dev_name;
+	abs_dev->id.bustype = BUS_I8042;
+	abs_dev->id.vendor = 0x0002;
+	abs_dev->id.product = PSMOUSE_VMMOUSE;
+	abs_dev->id.version = psmouse->model;
+	abs_dev->dev.parent = &psmouse->ps2dev.serio->dev;
+
+	/* Set absolute device capabilities */
+	input_set_capability(abs_dev, EV_KEY, BTN_LEFT);
+	input_set_capability(abs_dev, EV_KEY, BTN_RIGHT);
+	input_set_capability(abs_dev, EV_KEY, BTN_MIDDLE);
+	input_set_capability(abs_dev, EV_ABS, ABS_X);
+	input_set_capability(abs_dev, EV_ABS, ABS_Y);
+	input_set_abs_params(abs_dev, ABS_X, 0, VMMOUSE_MAX_X, 0, 0);
+	input_set_abs_params(abs_dev, ABS_Y, 0, VMMOUSE_MAX_Y, 0, 0);
+
+	error = input_register_device(priv->abs_dev);
+	if (error)
+		goto init_fail;
+
+	/* Add wheel capability to the relative device */
+	input_set_capability(rel_dev, EV_REL, REL_WHEEL);
+
+	psmouse->protocol_handler = vmmouse_process_byte;
+	psmouse->disconnect = vmmouse_disconnect;
+	psmouse->reconnect = vmmouse_reconnect;
+	psmouse->cleanup = vmmouse_reset;
+
+	return 0;
+
+init_fail:
+	vmmouse_disable(psmouse);
+	psmouse_reset(psmouse);
+	input_free_device(abs_dev);
+	kfree(priv);
+	psmouse->private = NULL;
+
+	return error;
+}