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, 445 insertions, 0 deletions

diff --git a/drivers/char/ps3flash.c b/drivers/char/ps3flash.c
new file mode 100644
index 000000000..c73f44307
--- /dev/null
+++ b/drivers/char/ps3flash.c
@@ -0,0 +1,445 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * PS3 FLASH ROM Storage Driver
+ *
+ * Copyright (C) 2007 Sony Computer Entertainment Inc.
+ * Copyright 2007 Sony Corp.
+ */
+
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/module.h>
+
+#include <asm/lv1call.h>
+#include <asm/ps3stor.h>
+
+
+#define DEVICE_NAME		"ps3flash"
+
+#define FLASH_BLOCK_SIZE	(256*1024)
+
+
+struct ps3flash_private {
+	struct mutex mutex;	/* Bounce buffer mutex */
+	u64 chunk_sectors;
+	int tag;		/* Start sector of buffer, -1 if invalid */
+	bool dirty;
+};
+
+static struct ps3_storage_device *ps3flash_dev;
+
+static int ps3flash_read_write_sectors(struct ps3_storage_device *dev,
+				       u64 start_sector, int write)
+{
+	struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
+	u64 res = ps3stor_read_write_sectors(dev, dev->bounce_lpar,
+					     start_sector, priv->chunk_sectors,
+					     write);
+	if (res) {
+		dev_err(&dev->sbd.core, "%s:%u: %s failed 0x%llx\n", __func__,
+			__LINE__, write ? "write" : "read", res);
+		return -EIO;
+	}
+	return 0;
+}
+
+static int ps3flash_writeback(struct ps3_storage_device *dev)
+{
+	struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
+	int res;
+
+	if (!priv->dirty || priv->tag < 0)
+		return 0;
+
+	res = ps3flash_read_write_sectors(dev, priv->tag, 1);
+	if (res)
+		return res;
+
+	priv->dirty = false;
+	return 0;
+}
+
+static int ps3flash_fetch(struct ps3_storage_device *dev, u64 start_sector)
+{
+	struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
+	int res;
+
+	if (start_sector == priv->tag)
+		return 0;
+
+	res = ps3flash_writeback(dev);
+	if (res)
+		return res;
+
+	priv->tag = -1;
+
+	res = ps3flash_read_write_sectors(dev, start_sector, 0);
+	if (res)
+		return res;
+
+	priv->tag = start_sector;
+	return 0;
+}
+
+static loff_t ps3flash_llseek(struct file *file, loff_t offset, int origin)
+{
+	struct ps3_storage_device *dev = ps3flash_dev;
+	return generic_file_llseek_size(file, offset, origin, MAX_LFS_FILESIZE,
+			dev->regions[dev->region_idx].size*dev->blk_size);
+}
+
+static ssize_t ps3flash_read(char __user *userbuf, void *kernelbuf,
+			     size_t count, loff_t *pos)
+{
+	struct ps3_storage_device *dev = ps3flash_dev;
+	struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
+	u64 size, sector, offset;
+	int res;
+	size_t remaining, n;
+	const void *src;
+
+	dev_dbg(&dev->sbd.core,
+		"%s:%u: Reading %zu bytes at position %lld to U0x%p/K0x%p\n",
+		__func__, __LINE__, count, *pos, userbuf, kernelbuf);
+
+	size = dev->regions[dev->region_idx].size*dev->blk_size;
+	if (*pos >= size || !count)
+		return 0;
+
+	if (*pos + count > size) {
+		dev_dbg(&dev->sbd.core,
+			"%s:%u Truncating count from %zu to %llu\n", __func__,
+			__LINE__, count, size - *pos);
+		count = size - *pos;
+	}
+
+	sector = *pos / dev->bounce_size * priv->chunk_sectors;
+	offset = *pos % dev->bounce_size;
+
+	remaining = count;
+	do {
+		n = min_t(u64, remaining, dev->bounce_size - offset);
+		src = dev->bounce_buf + offset;
+
+		mutex_lock(&priv->mutex);
+
+		res = ps3flash_fetch(dev, sector);
+		if (res)
+			goto fail;
+
+		dev_dbg(&dev->sbd.core,
+			"%s:%u: copy %lu bytes from 0x%p to U0x%p/K0x%p\n",
+			__func__, __LINE__, n, src, userbuf, kernelbuf);
+		if (userbuf) {
+			if (copy_to_user(userbuf, src, n)) {
+				res = -EFAULT;
+				goto fail;
+			}
+			userbuf += n;
+		}
+		if (kernelbuf) {
+			memcpy(kernelbuf, src, n);
+			kernelbuf += n;
+		}
+
+		mutex_unlock(&priv->mutex);
+
+		*pos += n;
+		remaining -= n;
+		sector += priv->chunk_sectors;
+		offset = 0;
+	} while (remaining > 0);
+
+	return count;
+
+fail:
+	mutex_unlock(&priv->mutex);
+	return res;
+}
+
+static ssize_t ps3flash_write(const char __user *userbuf,
+			      const void *kernelbuf, size_t count, loff_t *pos)
+{
+	struct ps3_storage_device *dev = ps3flash_dev;
+	struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
+	u64 size, sector, offset;
+	int res = 0;
+	size_t remaining, n;
+	void *dst;
+
+	dev_dbg(&dev->sbd.core,
+		"%s:%u: Writing %zu bytes at position %lld from U0x%p/K0x%p\n",
+		__func__, __LINE__, count, *pos, userbuf, kernelbuf);
+
+	size = dev->regions[dev->region_idx].size*dev->blk_size;
+	if (*pos >= size || !count)
+		return 0;
+
+	if (*pos + count > size) {
+		dev_dbg(&dev->sbd.core,
+			"%s:%u Truncating count from %zu to %llu\n", __func__,
+			__LINE__, count, size - *pos);
+		count = size - *pos;
+	}
+
+	sector = *pos / dev->bounce_size * priv->chunk_sectors;
+	offset = *pos % dev->bounce_size;
+
+	remaining = count;
+	do {
+		n = min_t(u64, remaining, dev->bounce_size - offset);
+		dst = dev->bounce_buf + offset;
+
+		mutex_lock(&priv->mutex);
+
+		if (n != dev->bounce_size)
+			res = ps3flash_fetch(dev, sector);
+		else if (sector != priv->tag)
+			res = ps3flash_writeback(dev);
+		if (res)
+			goto fail;
+
+		dev_dbg(&dev->sbd.core,
+			"%s:%u: copy %lu bytes from U0x%p/K0x%p to 0x%p\n",
+			__func__, __LINE__, n, userbuf, kernelbuf, dst);
+		if (userbuf) {
+			if (copy_from_user(dst, userbuf, n)) {
+				res = -EFAULT;
+				goto fail;
+			}
+			userbuf += n;
+		}
+		if (kernelbuf) {
+			memcpy(dst, kernelbuf, n);
+			kernelbuf += n;
+		}
+
+		priv->tag = sector;
+		priv->dirty = true;
+
+		mutex_unlock(&priv->mutex);
+
+		*pos += n;
+		remaining -= n;
+		sector += priv->chunk_sectors;
+		offset = 0;
+	} while (remaining > 0);
+
+	return count;
+
+fail:
+	mutex_unlock(&priv->mutex);
+	return res;
+}
+
+static ssize_t ps3flash_user_read(struct file *file, char __user *buf,
+				  size_t count, loff_t *pos)
+{
+	return ps3flash_read(buf, NULL, count, pos);
+}
+
+static ssize_t ps3flash_user_write(struct file *file, const char __user *buf,
+				   size_t count, loff_t *pos)
+{
+	return ps3flash_write(buf, NULL, count, pos);
+}
+
+static ssize_t ps3flash_kernel_read(void *buf, size_t count, loff_t pos)
+{
+	return ps3flash_read(NULL, buf, count, &pos);
+}
+
+static ssize_t ps3flash_kernel_write(const void *buf, size_t count,
+				     loff_t pos)
+{
+	ssize_t res;
+	int wb;
+
+	res = ps3flash_write(NULL, buf, count, &pos);
+	if (res < 0)
+		return res;
+
+	/* Make kernel writes synchronous */
+	wb = ps3flash_writeback(ps3flash_dev);
+	if (wb)
+		return wb;
+
+	return res;
+}
+
+static int ps3flash_flush(struct file *file, fl_owner_t id)
+{
+	return ps3flash_writeback(ps3flash_dev);
+}
+
+static int ps3flash_fsync(struct file *file, loff_t start, loff_t end, int datasync)
+{
+	struct inode *inode = file_inode(file);
+	int err;
+	inode_lock(inode);
+	err = ps3flash_writeback(ps3flash_dev);
+	inode_unlock(inode);
+	return err;
+}
+
+static irqreturn_t ps3flash_interrupt(int irq, void *data)
+{
+	struct ps3_storage_device *dev = data;
+	int res;
+	u64 tag, status;
+
+	res = lv1_storage_get_async_status(dev->sbd.dev_id, &tag, &status);
+
+	if (tag != dev->tag)
+		dev_err(&dev->sbd.core,
+			"%s:%u: tag mismatch, got %llx, expected %llx\n",
+			__func__, __LINE__, tag, dev->tag);
+
+	if (res) {
+		dev_err(&dev->sbd.core, "%s:%u: res=%d status=0x%llx\n",
+			__func__, __LINE__, res, status);
+	} else {
+		dev->lv1_status = status;
+		complete(&dev->done);
+	}
+	return IRQ_HANDLED;
+}
+
+static const struct file_operations ps3flash_fops = {
+	.owner	= THIS_MODULE,
+	.llseek	= ps3flash_llseek,
+	.read	= ps3flash_user_read,
+	.write	= ps3flash_user_write,
+	.flush	= ps3flash_flush,
+	.fsync	= ps3flash_fsync,
+};
+
+static const struct ps3_os_area_flash_ops ps3flash_kernel_ops = {
+	.read	= ps3flash_kernel_read,
+	.write	= ps3flash_kernel_write,
+};
+
+static struct miscdevice ps3flash_misc = {
+	.minor	= MISC_DYNAMIC_MINOR,
+	.name	= DEVICE_NAME,
+	.fops	= &ps3flash_fops,
+};
+
+static int ps3flash_probe(struct ps3_system_bus_device *_dev)
+{
+	struct ps3_storage_device *dev = to_ps3_storage_device(&_dev->core);
+	struct ps3flash_private *priv;
+	int error;
+	unsigned long tmp;
+
+	tmp = dev->regions[dev->region_idx].start*dev->blk_size;
+	if (tmp % FLASH_BLOCK_SIZE) {
+		dev_err(&dev->sbd.core,
+			"%s:%u region start %lu is not aligned\n", __func__,
+			__LINE__, tmp);
+		return -EINVAL;
+	}
+	tmp = dev->regions[dev->region_idx].size*dev->blk_size;
+	if (tmp % FLASH_BLOCK_SIZE) {
+		dev_err(&dev->sbd.core,
+			"%s:%u region size %lu is not aligned\n", __func__,
+			__LINE__, tmp);
+		return -EINVAL;
+	}
+
+	/* use static buffer, kmalloc cannot allocate 256 KiB */
+	if (!ps3flash_bounce_buffer.address)
+		return -ENODEV;
+
+	if (ps3flash_dev) {
+		dev_err(&dev->sbd.core,
+			"Only one FLASH device is supported\n");
+		return -EBUSY;
+	}
+
+	ps3flash_dev = dev;
+
+	priv = kzalloc_obj(*priv);
+	if (!priv) {
+		error = -ENOMEM;
+		goto fail;
+	}
+
+	ps3_system_bus_set_drvdata(&dev->sbd, priv);
+	mutex_init(&priv->mutex);
+	priv->tag = -1;
+
+	dev->bounce_size = ps3flash_bounce_buffer.size;
+	dev->bounce_buf = ps3flash_bounce_buffer.address;
+	priv->chunk_sectors = dev->bounce_size / dev->blk_size;
+
+	error = ps3stor_setup(dev, ps3flash_interrupt);
+	if (error)
+		goto fail_free_priv;
+
+	ps3flash_misc.parent = &dev->sbd.core;
+	error = misc_register(&ps3flash_misc);
+	if (error) {
+		dev_err(&dev->sbd.core, "%s:%u: misc_register failed %d\n",
+			__func__, __LINE__, error);
+		goto fail_teardown;
+	}
+
+	dev_info(&dev->sbd.core, "%s:%u: registered misc device %d\n",
+		 __func__, __LINE__, ps3flash_misc.minor);
+
+	ps3_os_area_flash_register(&ps3flash_kernel_ops);
+	return 0;
+
+fail_teardown:
+	ps3stor_teardown(dev);
+fail_free_priv:
+	kfree(priv);
+	ps3_system_bus_set_drvdata(&dev->sbd, NULL);
+fail:
+	ps3flash_dev = NULL;
+	return error;
+}
+
+static void ps3flash_remove(struct ps3_system_bus_device *_dev)
+{
+	struct ps3_storage_device *dev = to_ps3_storage_device(&_dev->core);
+
+	ps3_os_area_flash_register(NULL);
+	misc_deregister(&ps3flash_misc);
+	ps3stor_teardown(dev);
+	kfree(ps3_system_bus_get_drvdata(&dev->sbd));
+	ps3_system_bus_set_drvdata(&dev->sbd, NULL);
+	ps3flash_dev = NULL;
+}
+
+
+static struct ps3_system_bus_driver ps3flash = {
+	.match_id	= PS3_MATCH_ID_STOR_FLASH,
+	.core.name	= DEVICE_NAME,
+	.core.owner	= THIS_MODULE,
+	.probe		= ps3flash_probe,
+	.remove		= ps3flash_remove,
+	.shutdown	= ps3flash_remove,
+};
+
+
+static int __init ps3flash_init(void)
+{
+	return ps3_system_bus_driver_register(&ps3flash);
+}
+
+static void __exit ps3flash_exit(void)
+{
+	ps3_system_bus_driver_unregister(&ps3flash);
+}
+
+module_init(ps3flash_init);
+module_exit(ps3flash_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("PS3 FLASH ROM Storage Driver");
+MODULE_AUTHOR("Sony Corporation");
+MODULE_ALIAS(PS3_MODULE_ALIAS_STOR_FLASH);