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, 433 insertions, 0 deletions

diff --git a/drivers/misc/mei/init.c b/drivers/misc/mei/init.c
new file mode 100644
index 000000000..766f119f7
--- /dev/null
+++ b/drivers/misc/mei/init.c
@@ -0,0 +1,433 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2012-2022, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+
+#include <linux/export.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/delay.h>
+
+#include <linux/mei.h>
+
+#include "mei_dev.h"
+#include "hbm.h"
+#include "client.h"
+
+const char *mei_dev_state_str(int state)
+{
+#define MEI_DEV_STATE(state) case MEI_DEV_##state: return #state
+	switch (state) {
+	MEI_DEV_STATE(INITIALIZING);
+	MEI_DEV_STATE(INIT_CLIENTS);
+	MEI_DEV_STATE(ENABLED);
+	MEI_DEV_STATE(RESETTING);
+	MEI_DEV_STATE(DISABLED);
+	MEI_DEV_STATE(POWERING_DOWN);
+	MEI_DEV_STATE(POWER_DOWN);
+	MEI_DEV_STATE(POWER_UP);
+	default:
+		return "unknown";
+	}
+#undef MEI_DEV_STATE
+}
+
+const char *mei_pg_state_str(enum mei_pg_state state)
+{
+#define MEI_PG_STATE(state) case MEI_PG_##state: return #state
+	switch (state) {
+	MEI_PG_STATE(OFF);
+	MEI_PG_STATE(ON);
+	default:
+		return "unknown";
+	}
+#undef MEI_PG_STATE
+}
+
+/**
+ * mei_fw_status2str - convert fw status registers to printable string
+ *
+ * @fw_status:  firmware status
+ * @buf: string buffer at minimal size MEI_FW_STATUS_STR_SZ
+ * @len: buffer len must be >= MEI_FW_STATUS_STR_SZ
+ *
+ * Return: number of bytes written or -EINVAL if buffer is to small
+ */
+ssize_t mei_fw_status2str(struct mei_fw_status *fw_status,
+			  char *buf, size_t len)
+{
+	ssize_t cnt = 0;
+	int i;
+
+	buf[0] = '\0';
+
+	if (len < MEI_FW_STATUS_STR_SZ)
+		return -EINVAL;
+
+	for (i = 0; i < fw_status->count; i++)
+		cnt += scnprintf(buf + cnt, len - cnt, "%08X ",
+				fw_status->status[i]);
+
+	/* drop last space */
+	buf[cnt] = '\0';
+	return cnt;
+}
+EXPORT_SYMBOL_GPL(mei_fw_status2str);
+
+/**
+ * mei_cancel_work - Cancel mei background jobs
+ *
+ * @dev: the device structure
+ */
+void mei_cancel_work(struct mei_device *dev)
+{
+	cancel_work_sync(&dev->reset_work);
+	cancel_work_sync(&dev->bus_rescan_work);
+
+	cancel_delayed_work_sync(&dev->timer_work);
+}
+EXPORT_SYMBOL_GPL(mei_cancel_work);
+
+/**
+ * mei_reset - resets host and fw.
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success or < 0 if the reset hasn't succeeded
+ */
+int mei_reset(struct mei_device *dev)
+{
+	enum mei_dev_state state = dev->dev_state;
+	bool interrupts_enabled;
+	int ret;
+
+	if (state != MEI_DEV_INITIALIZING &&
+	    state != MEI_DEV_DISABLED &&
+	    state != MEI_DEV_POWER_DOWN &&
+	    state != MEI_DEV_POWER_UP) {
+		char fw_sts_str[MEI_FW_STATUS_STR_SZ];
+
+		mei_fw_status_str(dev, fw_sts_str, MEI_FW_STATUS_STR_SZ);
+		if (kind_is_gsc(dev) || kind_is_gscfi(dev)) {
+			dev_dbg(&dev->dev, "unexpected reset: dev_state = %s fw status = %s\n",
+				mei_dev_state_str(state), fw_sts_str);
+		} else {
+			dev_warn(&dev->dev, "unexpected reset: dev_state = %s fw status = %s\n",
+				 mei_dev_state_str(state), fw_sts_str);
+		}
+	}
+
+	mei_clear_interrupts(dev);
+
+	/* we're already in reset, cancel the init timer
+	 * if the reset was called due the hbm protocol error
+	 * we need to call it before hw start
+	 * so the hbm watchdog won't kick in
+	 */
+	mei_hbm_idle(dev);
+
+	/* enter reset flow */
+	interrupts_enabled = state != MEI_DEV_POWER_DOWN;
+	mei_set_devstate(dev, MEI_DEV_RESETTING);
+
+	dev->reset_count++;
+	if (dev->reset_count > MEI_MAX_CONSEC_RESET) {
+		dev_err(&dev->dev, "reset: reached maximal consecutive resets: disabling the device\n");
+		mei_set_devstate(dev, MEI_DEV_DISABLED);
+		return -ENODEV;
+	}
+
+	ret = mei_hw_reset(dev, interrupts_enabled);
+	/* fall through and remove the sw state even if hw reset has failed */
+
+	/* no need to clean up software state in case of power up */
+	if (state != MEI_DEV_INITIALIZING && state != MEI_DEV_POWER_UP)
+		mei_cl_all_disconnect(dev);
+
+	mei_hbm_reset(dev);
+
+	/* clean stale FW version */
+	dev->fw_ver_received = 0;
+
+	memset(dev->rd_msg_hdr, 0, sizeof(dev->rd_msg_hdr));
+
+	if (ret) {
+		dev_err(&dev->dev, "hw_reset failed ret = %d\n", ret);
+		return ret;
+	}
+
+	if (state == MEI_DEV_POWER_DOWN) {
+		dev_dbg(&dev->dev, "powering down: end of reset\n");
+		mei_set_devstate(dev, MEI_DEV_DISABLED);
+		return 0;
+	}
+
+	ret = mei_hw_start(dev);
+	if (ret) {
+		char fw_sts_str[MEI_FW_STATUS_STR_SZ];
+
+		mei_fw_status_str(dev, fw_sts_str, MEI_FW_STATUS_STR_SZ);
+		dev_err(&dev->dev, "hw_start failed ret = %d fw status = %s\n", ret, fw_sts_str);
+		return ret;
+	}
+
+	if (dev->dev_state != MEI_DEV_RESETTING) {
+		dev_dbg(&dev->dev, "wrong state = %d on link start\n", dev->dev_state);
+		return 0;
+	}
+
+	dev_dbg(&dev->dev, "link is established start sending messages.\n");
+
+	mei_set_devstate(dev, MEI_DEV_INIT_CLIENTS);
+	ret = mei_hbm_start_req(dev);
+	if (ret) {
+		dev_err(&dev->dev, "hbm_start failed ret = %d\n", ret);
+		mei_set_devstate(dev, MEI_DEV_RESETTING);
+		return ret;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(mei_reset);
+
+/**
+ * mei_start - initializes host and fw to start work.
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+int mei_start(struct mei_device *dev)
+{
+	int ret;
+
+	mutex_lock(&dev->device_lock);
+
+	/* acknowledge interrupt and stop interrupts */
+	mei_clear_interrupts(dev);
+
+	ret = mei_hw_config(dev);
+	if (ret)
+		goto err;
+
+	dev_dbg(&dev->dev, "reset in start the mei device.\n");
+
+	dev->reset_count = 0;
+	do {
+		mei_set_devstate(dev, MEI_DEV_INITIALIZING);
+		ret = mei_reset(dev);
+
+		if (ret == -ENODEV || dev->dev_state == MEI_DEV_DISABLED) {
+			dev_err(&dev->dev, "reset failed ret = %d", ret);
+			goto err;
+		}
+	} while (ret);
+
+	if (mei_hbm_start_wait(dev)) {
+		dev_err(&dev->dev, "HBM haven't started");
+		goto err;
+	}
+
+	if (!mei_hbm_version_is_supported(dev)) {
+		dev_dbg(&dev->dev, "MEI start failed.\n");
+		goto err;
+	}
+
+	dev_dbg(&dev->dev, "link layer has been established.\n");
+
+	mutex_unlock(&dev->device_lock);
+	return 0;
+err:
+	dev_err(&dev->dev, "link layer initialization failed.\n");
+	mei_set_devstate(dev, MEI_DEV_DISABLED);
+	mutex_unlock(&dev->device_lock);
+	return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(mei_start);
+
+/**
+ * mei_restart - restart device after suspend
+ *
+ * @dev: the device structure
+ *
+ * Return: 0 on success or -ENODEV if the restart hasn't succeeded
+ */
+int mei_restart(struct mei_device *dev)
+{
+	int err;
+
+	mutex_lock(&dev->device_lock);
+
+	mei_set_devstate(dev, MEI_DEV_POWER_UP);
+	dev->reset_count = 0;
+
+	err = mei_reset(dev);
+
+	mutex_unlock(&dev->device_lock);
+
+	if (err == -ENODEV || dev->dev_state == MEI_DEV_DISABLED) {
+		dev_err(&dev->dev, "device disabled = %d\n", err);
+		return -ENODEV;
+	}
+
+	/* try to start again */
+	if (err)
+		schedule_work(&dev->reset_work);
+
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(mei_restart);
+
+static void mei_reset_work(struct work_struct *work)
+{
+	struct mei_device *dev =
+		container_of(work, struct mei_device,  reset_work);
+	int ret;
+
+	mei_clear_interrupts(dev);
+	mei_synchronize_irq(dev);
+
+	mutex_lock(&dev->device_lock);
+
+	ret = mei_reset(dev);
+
+	mutex_unlock(&dev->device_lock);
+
+	if (dev->dev_state == MEI_DEV_DISABLED) {
+		dev_err(&dev->dev, "device disabled = %d\n", ret);
+		return;
+	}
+
+	/* retry reset in case of failure */
+	if (ret)
+		schedule_work(&dev->reset_work);
+}
+
+void mei_stop(struct mei_device *dev)
+{
+	dev_dbg(&dev->dev, "stopping the device.\n");
+
+	mutex_lock(&dev->device_lock);
+	mei_set_devstate(dev, MEI_DEV_POWERING_DOWN);
+	mutex_unlock(&dev->device_lock);
+	mei_cl_bus_remove_devices(dev);
+	mutex_lock(&dev->device_lock);
+	mei_set_devstate(dev, MEI_DEV_POWER_DOWN);
+	mutex_unlock(&dev->device_lock);
+
+	mei_cancel_work(dev);
+
+	mei_clear_interrupts(dev);
+	mei_synchronize_irq(dev);
+	/* to catch HW-initiated reset */
+	mei_cancel_work(dev);
+
+	mutex_lock(&dev->device_lock);
+
+	mei_reset(dev);
+	/* move device to disabled state unconditionally */
+	mei_set_devstate(dev, MEI_DEV_DISABLED);
+
+	mutex_unlock(&dev->device_lock);
+}
+EXPORT_SYMBOL_GPL(mei_stop);
+
+/**
+ * mei_write_is_idle - check if the write queues are idle
+ *
+ * @dev: the device structure
+ *
+ * Return: true of there is no pending write
+ */
+bool mei_write_is_idle(struct mei_device *dev)
+{
+	bool idle = (dev->dev_state == MEI_DEV_ENABLED &&
+		!dev->pg_blocked &&
+		list_empty(&dev->ctrl_wr_list) &&
+		list_empty(&dev->write_list)   &&
+		list_empty(&dev->write_waiting_list));
+
+	dev_dbg(&dev->dev, "write pg: is idle[%d] state=%s blocked=%d ctrl=%d write=%d wwait=%d\n",
+		idle,
+		mei_dev_state_str(dev->dev_state),
+		dev->pg_blocked,
+		list_empty(&dev->ctrl_wr_list),
+		list_empty(&dev->write_list),
+		list_empty(&dev->write_waiting_list));
+
+	return idle;
+}
+EXPORT_SYMBOL_GPL(mei_write_is_idle);
+
+/**
+ * mei_device_init - initialize mei_device structure
+ *
+ * @dev: the mei device
+ * @parent: the parent device
+ * @slow_fw: configure longer timeouts as FW is slow
+ * @hw_ops: hw operations
+ */
+void mei_device_init(struct mei_device *dev,
+		     struct device *parent,
+		     bool slow_fw,
+		     const struct mei_hw_ops *hw_ops)
+{
+	/* setup our list array */
+	INIT_LIST_HEAD(&dev->file_list);
+	INIT_LIST_HEAD(&dev->device_list);
+	INIT_LIST_HEAD(&dev->me_clients);
+	mutex_init(&dev->device_lock);
+	init_rwsem(&dev->me_clients_rwsem);
+	mutex_init(&dev->cl_bus_lock);
+	init_waitqueue_head(&dev->wait_hw_ready);
+	init_waitqueue_head(&dev->wait_pg);
+	init_waitqueue_head(&dev->wait_hbm_start);
+	dev->dev_state = MEI_DEV_UNINITIALIZED;
+	init_waitqueue_head(&dev->wait_dev_state);
+	dev->reset_count = 0;
+
+	INIT_LIST_HEAD(&dev->write_list);
+	INIT_LIST_HEAD(&dev->write_waiting_list);
+	INIT_LIST_HEAD(&dev->ctrl_wr_list);
+	INIT_LIST_HEAD(&dev->ctrl_rd_list);
+	dev->tx_queue_limit = MEI_TX_QUEUE_LIMIT_DEFAULT;
+
+	INIT_DELAYED_WORK(&dev->timer_work, mei_timer);
+	INIT_WORK(&dev->reset_work, mei_reset_work);
+	INIT_WORK(&dev->bus_rescan_work, mei_cl_bus_rescan_work);
+
+	bitmap_zero(dev->host_clients_map, MEI_CLIENTS_MAX);
+	dev->open_handle_count = 0;
+
+	dev->pxp_mode = MEI_DEV_PXP_DEFAULT;
+	dev->gsc_reset_to_pxp = MEI_DEV_RESET_TO_PXP_DEFAULT;
+
+	/*
+	 * Reserving the first client ID
+	 * 0: Reserved for MEI Bus Message communications
+	 */
+	bitmap_set(dev->host_clients_map, 0, 1);
+
+	dev->pg_event = MEI_PG_EVENT_IDLE;
+	dev->ops      = hw_ops;
+	dev->parent   = parent;
+
+	dev->timeouts.hw_ready = mei_secs_to_jiffies(MEI_HW_READY_TIMEOUT);
+	dev->timeouts.connect = MEI_CONNECT_TIMEOUT;
+	dev->timeouts.client_init = MEI_CLIENTS_INIT_TIMEOUT;
+	dev->timeouts.pgi = mei_secs_to_jiffies(MEI_PGI_TIMEOUT);
+	dev->timeouts.d0i3 = mei_secs_to_jiffies(MEI_D0I3_TIMEOUT);
+	if (slow_fw) {
+		dev->timeouts.cl_connect = mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT_SLOW);
+		dev->timeouts.hbm = mei_secs_to_jiffies(MEI_HBM_TIMEOUT_SLOW);
+		dev->timeouts.mkhi_recv = msecs_to_jiffies(MKHI_RCV_TIMEOUT_SLOW);
+	} else {
+		dev->timeouts.cl_connect = mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT);
+		dev->timeouts.hbm = mei_secs_to_jiffies(MEI_HBM_TIMEOUT);
+		dev->timeouts.mkhi_recv = msecs_to_jiffies(MKHI_RCV_TIMEOUT);
+	}
+	dev->timeouts.link_reset_wait = msecs_to_jiffies(MEI_LINK_RESET_WAIT_TIMEOUT_MSEC);
+}
+EXPORT_SYMBOL_GPL(mei_device_init);