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, 383 insertions, 0 deletions

diff --git a/sound/soc/sof/sof-client-ipc-flood-test.c b/sound/soc/sof/sof-client-ipc-flood-test.c
new file mode 100644
index 000000000..2396cc354
--- /dev/null
+++ b/sound/soc/sof/sof-client-ipc-flood-test.c
@@ -0,0 +1,383 @@
+// SPDX-License-Identifier: GPL-2.0-only
+//
+// Copyright(c) 2022 Intel Corporation
+//
+// Authors: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
+//	    Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
+//
+
+#include <linux/auxiliary_bus.h>
+#include <linux/completion.h>
+#include <linux/debugfs.h>
+#include <linux/ktime.h>
+#include <linux/module.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <sound/sof/header.h>
+
+#include "sof-client.h"
+
+#define MAX_IPC_FLOOD_DURATION_MS	1000
+#define MAX_IPC_FLOOD_COUNT		10000
+#define IPC_FLOOD_TEST_RESULT_LEN	512
+#define SOF_IPC_CLIENT_SUSPEND_DELAY_MS	3000
+
+#define DEBUGFS_IPC_FLOOD_COUNT		"ipc_flood_count"
+#define DEBUGFS_IPC_FLOOD_DURATION	"ipc_flood_duration_ms"
+
+struct sof_ipc_flood_priv {
+	struct dentry *dfs_root;
+	struct dentry *dfs_link[2];
+	char *buf;
+};
+
+static int sof_ipc_flood_dfs_open(struct inode *inode, struct file *file)
+{
+	struct sof_client_dev *cdev = inode->i_private;
+	int ret;
+
+	if (sof_client_get_fw_state(cdev) == SOF_FW_CRASHED)
+		return -ENODEV;
+
+	ret = debugfs_file_get(file->f_path.dentry);
+	if (unlikely(ret))
+		return ret;
+
+	ret = simple_open(inode, file);
+	if (ret)
+		debugfs_file_put(file->f_path.dentry);
+
+	return ret;
+}
+
+/*
+ * helper function to perform the flood test. Only one of the two params, ipc_duration_ms
+ * or ipc_count, will be non-zero and will determine the type of test
+ */
+static int sof_debug_ipc_flood_test(struct sof_client_dev *cdev,
+				    bool flood_duration_test,
+				    unsigned long ipc_duration_ms,
+				    unsigned long ipc_count)
+{
+	struct sof_ipc_flood_priv *priv = cdev->data;
+	struct device *dev = &cdev->auxdev.dev;
+	struct sof_ipc_cmd_hdr hdr;
+	u64 min_response_time = U64_MAX;
+	ktime_t start, end, test_end;
+	u64 avg_response_time = 0;
+	u64 max_response_time = 0;
+	u64 ipc_response_time;
+	int i = 0;
+	int ret;
+
+	/* configure test IPC */
+	hdr.cmd = SOF_IPC_GLB_TEST_MSG | SOF_IPC_TEST_IPC_FLOOD;
+	hdr.size = sizeof(hdr);
+
+	/* set test end time for duration flood test */
+	if (flood_duration_test)
+		test_end = ktime_get_ns() + ipc_duration_ms * NSEC_PER_MSEC;
+
+	/* send test IPC's */
+	while (1) {
+		start = ktime_get();
+		ret = sof_client_ipc_tx_message_no_reply(cdev, &hdr);
+		end = ktime_get();
+
+		if (ret < 0)
+			break;
+
+		/* compute min and max response times */
+		ipc_response_time = ktime_to_ns(ktime_sub(end, start));
+		min_response_time = min(min_response_time, ipc_response_time);
+		max_response_time = max(max_response_time, ipc_response_time);
+
+		/* sum up response times */
+		avg_response_time += ipc_response_time;
+		i++;
+
+		/* test complete? */
+		if (flood_duration_test) {
+			if (ktime_to_ns(end) >= test_end)
+				break;
+		} else {
+			if (i == ipc_count)
+				break;
+		}
+	}
+
+	if (ret < 0)
+		dev_err(dev, "ipc flood test failed at %d iterations\n", i);
+
+	/* return if the first IPC fails */
+	if (!i)
+		return ret;
+
+	/* compute average response time */
+	do_div(avg_response_time, i);
+
+	/* clear previous test output */
+	memset(priv->buf, 0, IPC_FLOOD_TEST_RESULT_LEN);
+
+	if (!ipc_count) {
+		dev_dbg(dev, "IPC Flood test duration: %lums\n", ipc_duration_ms);
+		snprintf(priv->buf, IPC_FLOOD_TEST_RESULT_LEN,
+			 "IPC Flood test duration: %lums\n", ipc_duration_ms);
+	}
+
+	dev_dbg(dev, "IPC Flood count: %d, Avg response time: %lluns\n",
+		i, avg_response_time);
+	dev_dbg(dev, "Max response time: %lluns\n", max_response_time);
+	dev_dbg(dev, "Min response time: %lluns\n", min_response_time);
+
+	/* format output string and save test results */
+	snprintf(priv->buf + strlen(priv->buf),
+		 IPC_FLOOD_TEST_RESULT_LEN - strlen(priv->buf),
+		 "IPC Flood count: %d\nAvg response time: %lluns\n",
+		 i, avg_response_time);
+
+	snprintf(priv->buf + strlen(priv->buf),
+		 IPC_FLOOD_TEST_RESULT_LEN - strlen(priv->buf),
+		 "Max response time: %lluns\nMin response time: %lluns\n",
+		 max_response_time, min_response_time);
+
+	return ret;
+}
+
+/*
+ * Writing to the debugfs entry initiates the IPC flood test based on
+ * the IPC count or the duration specified by the user.
+ */
+static ssize_t sof_ipc_flood_dfs_write(struct file *file, const char __user *buffer,
+				       size_t count, loff_t *ppos)
+{
+	struct sof_client_dev *cdev = file->private_data;
+	struct device *dev = &cdev->auxdev.dev;
+	unsigned long ipc_duration_ms = 0;
+	bool flood_duration_test = false;
+	unsigned long ipc_count = 0;
+	int err;
+	char *string;
+	int ret;
+
+	if (*ppos != 0)
+		return -EINVAL;
+
+	string = kzalloc(count + 1, GFP_KERNEL);
+	if (!string)
+		return -ENOMEM;
+
+	if (copy_from_user(string, buffer, count)) {
+		ret = -EFAULT;
+		goto out;
+	}
+
+	/*
+	 * write op is only supported for ipc_flood_count or
+	 * ipc_flood_duration_ms debugfs entries atm.
+	 * ipc_flood_count floods the DSP with the number of IPC's specified.
+	 * ipc_duration_ms test floods the DSP for the time specified
+	 * in the debugfs entry.
+	 */
+	if (debugfs_get_aux_num(file))
+		flood_duration_test = true;
+
+	/* test completion criterion */
+	if (flood_duration_test)
+		ret = kstrtoul(string, 0, &ipc_duration_ms);
+	else
+		ret = kstrtoul(string, 0, &ipc_count);
+	if (ret < 0)
+		goto out;
+
+	/* limit max duration/ipc count for flood test */
+	if (flood_duration_test) {
+		if (!ipc_duration_ms) {
+			ret = count;
+			goto out;
+		}
+
+		/* find the minimum. min() is not used to avoid warnings */
+		if (ipc_duration_ms > MAX_IPC_FLOOD_DURATION_MS)
+			ipc_duration_ms = MAX_IPC_FLOOD_DURATION_MS;
+	} else {
+		if (!ipc_count) {
+			ret = count;
+			goto out;
+		}
+
+		/* find the minimum. min() is not used to avoid warnings */
+		if (ipc_count > MAX_IPC_FLOOD_COUNT)
+			ipc_count = MAX_IPC_FLOOD_COUNT;
+	}
+
+	ret = pm_runtime_resume_and_get(dev);
+	if (ret < 0 && ret != -EACCES) {
+		dev_err_ratelimited(dev, "debugfs write failed to resume %d\n", ret);
+		goto out;
+	}
+
+	ret = sof_client_boot_dsp(cdev);
+	if (!ret)
+		ret = sof_debug_ipc_flood_test(cdev, flood_duration_test,
+					       ipc_duration_ms, ipc_count);
+
+	err = pm_runtime_put_autosuspend(dev);
+	if (err < 0)
+		dev_err_ratelimited(dev, "debugfs write failed to idle %d\n", err);
+
+	/* return count if test is successful */
+	if (ret >= 0)
+		ret = count;
+out:
+	kfree(string);
+	return ret;
+}
+
+/* return the result of the last IPC flood test */
+static ssize_t sof_ipc_flood_dfs_read(struct file *file, char __user *buffer,
+				      size_t count, loff_t *ppos)
+{
+	struct sof_client_dev *cdev = file->private_data;
+	struct sof_ipc_flood_priv *priv = cdev->data;
+	size_t size_ret;
+
+	if (*ppos)
+		return 0;
+
+	count = min_t(size_t, count, strlen(priv->buf));
+	size_ret = copy_to_user(buffer, priv->buf, count);
+	if (size_ret)
+		return -EFAULT;
+
+	*ppos += count;
+	return count;
+}
+
+static int sof_ipc_flood_dfs_release(struct inode *inode, struct file *file)
+{
+	debugfs_file_put(file->f_path.dentry);
+
+	return 0;
+}
+
+static const struct file_operations sof_ipc_flood_fops = {
+	.open = sof_ipc_flood_dfs_open,
+	.read = sof_ipc_flood_dfs_read,
+	.llseek = default_llseek,
+	.write = sof_ipc_flood_dfs_write,
+	.release = sof_ipc_flood_dfs_release,
+
+	.owner = THIS_MODULE,
+};
+
+/*
+ * The IPC test client creates a couple of debugfs entries that will be used
+ * flood tests. Users can write to these entries to execute the IPC flood test
+ * by specifying either the number of IPCs to flood the DSP with or the duration
+ * (in ms) for which the DSP should be flooded with test IPCs. At the
+ * end of each test, the average, min and max response times are reported back.
+ * The results of the last flood test can be accessed by reading the debugfs
+ * entries.
+ */
+static int sof_ipc_flood_probe(struct auxiliary_device *auxdev,
+			       const struct auxiliary_device_id *id)
+{
+	struct sof_client_dev *cdev = auxiliary_dev_to_sof_client_dev(auxdev);
+	struct dentry *debugfs_root = sof_client_get_debugfs_root(cdev);
+	struct device *dev = &auxdev->dev;
+	struct sof_ipc_flood_priv *priv;
+
+	/* allocate memory for client data */
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->buf = devm_kmalloc(dev, IPC_FLOOD_TEST_RESULT_LEN, GFP_KERNEL);
+	if (!priv->buf)
+		return -ENOMEM;
+
+	cdev->data = priv;
+
+	/* create debugfs root folder with device name under parent SOF dir */
+	priv->dfs_root = debugfs_create_dir(dev_name(dev), debugfs_root);
+	if (!IS_ERR_OR_NULL(priv->dfs_root)) {
+		/* create read-write ipc_flood_count debugfs entry */
+		debugfs_create_file_aux_num(DEBUGFS_IPC_FLOOD_COUNT, 0644,
+				    priv->dfs_root, cdev, 0, &sof_ipc_flood_fops);
+
+		/* create read-write ipc_flood_duration_ms debugfs entry */
+		debugfs_create_file_aux_num(DEBUGFS_IPC_FLOOD_DURATION, 0644,
+				    priv->dfs_root, cdev, 1, &sof_ipc_flood_fops);
+
+		if (auxdev->id == 0) {
+			/*
+			 * Create symlinks for backwards compatibility to the
+			 * first IPC flood test instance
+			 */
+			char target[100];
+
+			snprintf(target, 100, "%s/" DEBUGFS_IPC_FLOOD_COUNT,
+				 dev_name(dev));
+			priv->dfs_link[0] =
+				debugfs_create_symlink(DEBUGFS_IPC_FLOOD_COUNT,
+						       debugfs_root, target);
+
+			snprintf(target, 100, "%s/" DEBUGFS_IPC_FLOOD_DURATION,
+				 dev_name(dev));
+			priv->dfs_link[1] =
+				debugfs_create_symlink(DEBUGFS_IPC_FLOOD_DURATION,
+						       debugfs_root, target);
+		}
+	}
+
+	/* enable runtime PM */
+	pm_runtime_set_autosuspend_delay(dev, SOF_IPC_CLIENT_SUSPEND_DELAY_MS);
+	pm_runtime_use_autosuspend(dev);
+	pm_runtime_enable(dev);
+	pm_runtime_mark_last_busy(dev);
+	pm_runtime_idle(dev);
+
+	return 0;
+}
+
+static void sof_ipc_flood_remove(struct auxiliary_device *auxdev)
+{
+	struct sof_client_dev *cdev = auxiliary_dev_to_sof_client_dev(auxdev);
+	struct sof_ipc_flood_priv *priv = cdev->data;
+
+	pm_runtime_disable(&auxdev->dev);
+
+	if (auxdev->id == 0) {
+		debugfs_remove(priv->dfs_link[0]);
+		debugfs_remove(priv->dfs_link[1]);
+	}
+
+	debugfs_remove_recursive(priv->dfs_root);
+}
+
+static const struct auxiliary_device_id sof_ipc_flood_client_id_table[] = {
+	{ .name = "snd_sof.ipc_flood" },
+	{},
+};
+MODULE_DEVICE_TABLE(auxiliary, sof_ipc_flood_client_id_table);
+
+/*
+ * No need for driver pm_ops as the generic pm callbacks in the auxiliary bus
+ * type are enough to ensure that the parent SOF device resumes to bring the DSP
+ * back to D0.
+ * Driver name will be set based on KBUILD_MODNAME.
+ */
+static struct auxiliary_driver sof_ipc_flood_client_drv = {
+	.probe = sof_ipc_flood_probe,
+	.remove = sof_ipc_flood_remove,
+
+	.id_table = sof_ipc_flood_client_id_table,
+};
+
+module_auxiliary_driver(sof_ipc_flood_client_drv);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("SOF IPC Flood Test Client Driver");
+MODULE_IMPORT_NS("SND_SOC_SOF_CLIENT");