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, 329 insertions, 0 deletions

diff --git a/drivers/soc/fsl/dpaa2-console.c b/drivers/soc/fsl/dpaa2-console.c
new file mode 100644
index 000000000..7f2ffe38d
--- /dev/null
+++ b/drivers/soc/fsl/dpaa2-console.c
@@ -0,0 +1,329 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
+/*
+ * Freescale DPAA2 Platforms Console Driver
+ *
+ * Copyright 2015-2016 Freescale Semiconductor Inc.
+ * Copyright 2018 NXP
+ */
+
+#define pr_fmt(fmt) "dpaa2-console: " fmt
+
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/miscdevice.h>
+#include <linux/platform_device.h>
+#include <linux/uaccess.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/io.h>
+
+/* MC firmware base low/high registers indexes */
+#define MCFBALR_OFFSET 0
+#define MCFBAHR_OFFSET 1
+
+/* Bit masks used to get the most/least significant part of the MC base addr */
+#define MC_FW_ADDR_MASK_HIGH 0x1FFFF
+#define MC_FW_ADDR_MASK_LOW  0xE0000000
+
+#define MC_BUFFER_OFFSET 0x01000000
+#define MC_BUFFER_SIZE   (1024 * 1024 * 16)
+#define MC_OFFSET_DELTA  MC_BUFFER_OFFSET
+
+#define AIOP_BUFFER_OFFSET 0x06000000
+#define AIOP_BUFFER_SIZE   (1024 * 1024 * 16)
+#define AIOP_OFFSET_DELTA  0
+
+#define LOG_HEADER_FLAG_BUFFER_WRAPAROUND 0x80000000
+#define LAST_BYTE(a) ((a) & ~(LOG_HEADER_FLAG_BUFFER_WRAPAROUND))
+
+/* MC and AIOP Magic words */
+#define MAGIC_MC   0x4d430100
+#define MAGIC_AIOP 0x41494F50
+
+struct log_header {
+	__le32 magic_word;
+	char reserved[4];
+	__le32 buf_start;
+	__le32 buf_length;
+	__le32 last_byte;
+};
+
+struct console_data {
+	void __iomem *map_addr;
+	struct log_header __iomem *hdr;
+	void __iomem *start_addr;
+	void __iomem *end_addr;
+	void __iomem *end_of_data;
+	void __iomem *cur_ptr;
+};
+
+static struct resource mc_base_addr;
+
+static inline void adjust_end(struct console_data *cd)
+{
+	u32 last_byte = readl(&cd->hdr->last_byte);
+
+	cd->end_of_data = cd->start_addr + LAST_BYTE(last_byte);
+}
+
+static u64 get_mc_fw_base_address(void)
+{
+	u64 mcfwbase = 0ULL;
+	u32 __iomem *mcfbaregs;
+
+	mcfbaregs = ioremap(mc_base_addr.start, resource_size(&mc_base_addr));
+	if (!mcfbaregs) {
+		pr_err("could not map MC Firmware Base registers\n");
+		return 0;
+	}
+
+	mcfwbase  = readl(mcfbaregs + MCFBAHR_OFFSET) &
+			  MC_FW_ADDR_MASK_HIGH;
+	mcfwbase <<= 32;
+	mcfwbase |= readl(mcfbaregs + MCFBALR_OFFSET) & MC_FW_ADDR_MASK_LOW;
+	iounmap(mcfbaregs);
+
+	pr_debug("MC base address at 0x%016llx\n", mcfwbase);
+	return mcfwbase;
+}
+
+static ssize_t dpaa2_console_size(struct console_data *cd)
+{
+	ssize_t size;
+
+	if (cd->cur_ptr <= cd->end_of_data)
+		size = cd->end_of_data - cd->cur_ptr;
+	else
+		size = (cd->end_addr - cd->cur_ptr) +
+			(cd->end_of_data - cd->start_addr);
+
+	return size;
+}
+
+static int dpaa2_generic_console_open(struct inode *node, struct file *fp,
+				      u64 offset, u64 size,
+				      u32 expected_magic,
+				      u32 offset_delta)
+{
+	u32 read_magic, wrapped, last_byte, buf_start, buf_length;
+	struct console_data *cd;
+	u64 base_addr;
+	int err;
+
+	cd = kmalloc_obj(*cd);
+	if (!cd)
+		return -ENOMEM;
+
+	base_addr = get_mc_fw_base_address();
+	if (!base_addr) {
+		err = -EIO;
+		goto err_fwba;
+	}
+
+	cd->map_addr = ioremap(base_addr + offset, size);
+	if (!cd->map_addr) {
+		pr_err("cannot map console log memory\n");
+		err = -EIO;
+		goto err_ioremap;
+	}
+
+	cd->hdr = (struct log_header __iomem *)cd->map_addr;
+	read_magic = readl(&cd->hdr->magic_word);
+	last_byte =  readl(&cd->hdr->last_byte);
+	buf_start =  readl(&cd->hdr->buf_start);
+	buf_length = readl(&cd->hdr->buf_length);
+
+	if (read_magic != expected_magic) {
+		pr_warn("expected = %08x, read = %08x\n",
+			expected_magic, read_magic);
+		err = -EIO;
+		goto err_magic;
+	}
+
+	cd->start_addr = cd->map_addr + buf_start - offset_delta;
+	cd->end_addr = cd->start_addr + buf_length;
+
+	wrapped = last_byte & LOG_HEADER_FLAG_BUFFER_WRAPAROUND;
+
+	adjust_end(cd);
+	if (wrapped && cd->end_of_data != cd->end_addr)
+		cd->cur_ptr = cd->end_of_data + 1;
+	else
+		cd->cur_ptr = cd->start_addr;
+
+	fp->private_data = cd;
+
+	return 0;
+
+err_magic:
+	iounmap(cd->map_addr);
+
+err_ioremap:
+err_fwba:
+	kfree(cd);
+
+	return err;
+}
+
+static int dpaa2_mc_console_open(struct inode *node, struct file *fp)
+{
+	return dpaa2_generic_console_open(node, fp,
+					  MC_BUFFER_OFFSET, MC_BUFFER_SIZE,
+					  MAGIC_MC, MC_OFFSET_DELTA);
+}
+
+static int dpaa2_aiop_console_open(struct inode *node, struct file *fp)
+{
+	return dpaa2_generic_console_open(node, fp,
+					  AIOP_BUFFER_OFFSET, AIOP_BUFFER_SIZE,
+					  MAGIC_AIOP, AIOP_OFFSET_DELTA);
+}
+
+static int dpaa2_console_close(struct inode *node, struct file *fp)
+{
+	struct console_data *cd = fp->private_data;
+
+	iounmap(cd->map_addr);
+	kfree(cd);
+	return 0;
+}
+
+static ssize_t dpaa2_console_read(struct file *fp, char __user *buf,
+				  size_t count, loff_t *f_pos)
+{
+	struct console_data *cd = fp->private_data;
+	size_t bytes = dpaa2_console_size(cd);
+	size_t bytes_end = cd->end_addr - cd->cur_ptr;
+	size_t written = 0;
+	void *kbuf;
+	int err;
+
+	/* Check if we need to adjust the end of data addr */
+	adjust_end(cd);
+
+	if (cd->end_of_data == cd->cur_ptr)
+		return 0;
+
+	if (count < bytes)
+		bytes = count;
+
+	kbuf = kmalloc(bytes, GFP_KERNEL);
+	if (!kbuf)
+		return -ENOMEM;
+
+	if (bytes > bytes_end) {
+		memcpy_fromio(kbuf, cd->cur_ptr, bytes_end);
+		if (copy_to_user(buf, kbuf, bytes_end)) {
+			err = -EFAULT;
+			goto err_free_buf;
+		}
+		buf += bytes_end;
+		cd->cur_ptr = cd->start_addr;
+		bytes -= bytes_end;
+		written += bytes_end;
+	}
+
+	memcpy_fromio(kbuf, cd->cur_ptr, bytes);
+	if (copy_to_user(buf, kbuf, bytes)) {
+		err = -EFAULT;
+		goto err_free_buf;
+	}
+	cd->cur_ptr += bytes;
+	written += bytes;
+
+	kfree(kbuf);
+	return written;
+
+err_free_buf:
+	kfree(kbuf);
+
+	return err;
+}
+
+static const struct file_operations dpaa2_mc_console_fops = {
+	.owner          = THIS_MODULE,
+	.open           = dpaa2_mc_console_open,
+	.release        = dpaa2_console_close,
+	.read           = dpaa2_console_read,
+};
+
+static struct miscdevice dpaa2_mc_console_dev = {
+	.minor = MISC_DYNAMIC_MINOR,
+	.name = "dpaa2_mc_console",
+	.fops = &dpaa2_mc_console_fops
+};
+
+static const struct file_operations dpaa2_aiop_console_fops = {
+	.owner          = THIS_MODULE,
+	.open           = dpaa2_aiop_console_open,
+	.release        = dpaa2_console_close,
+	.read           = dpaa2_console_read,
+};
+
+static struct miscdevice dpaa2_aiop_console_dev = {
+	.minor = MISC_DYNAMIC_MINOR,
+	.name = "dpaa2_aiop_console",
+	.fops = &dpaa2_aiop_console_fops
+};
+
+static int dpaa2_console_probe(struct platform_device *pdev)
+{
+	int error;
+
+	error = of_address_to_resource(pdev->dev.of_node, 0, &mc_base_addr);
+	if (error < 0) {
+		pr_err("of_address_to_resource() failed for %pOF with %d\n",
+		       pdev->dev.of_node, error);
+		return error;
+	}
+
+	error = misc_register(&dpaa2_mc_console_dev);
+	if (error) {
+		pr_err("cannot register device %s\n",
+		       dpaa2_mc_console_dev.name);
+		goto err_register_mc;
+	}
+
+	error = misc_register(&dpaa2_aiop_console_dev);
+	if (error) {
+		pr_err("cannot register device %s\n",
+		       dpaa2_aiop_console_dev.name);
+		goto err_register_aiop;
+	}
+
+	return 0;
+
+err_register_aiop:
+	misc_deregister(&dpaa2_mc_console_dev);
+err_register_mc:
+	return error;
+}
+
+static void dpaa2_console_remove(struct platform_device *pdev)
+{
+	misc_deregister(&dpaa2_mc_console_dev);
+	misc_deregister(&dpaa2_aiop_console_dev);
+}
+
+static const struct of_device_id dpaa2_console_match_table[] = {
+	{ .compatible = "fsl,dpaa2-console",},
+	{},
+};
+
+MODULE_DEVICE_TABLE(of, dpaa2_console_match_table);
+
+static struct platform_driver dpaa2_console_driver = {
+	.driver = {
+		   .name = "dpaa2-console",
+		   .pm = NULL,
+		   .of_match_table = dpaa2_console_match_table,
+		   },
+	.probe = dpaa2_console_probe,
+	.remove = dpaa2_console_remove,
+};
+module_platform_driver(dpaa2_console_driver);
+
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_AUTHOR("Roy Pledge <roy.pledge@nxp.com>");
+MODULE_DESCRIPTION("DPAA2 console driver");