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, 200 insertions, 0 deletions

diff --git a/drivers/mtd/maps/physmap-gemini.c b/drivers/mtd/maps/physmap-gemini.c
new file mode 100644
index 000000000..1c34b4ef7
--- /dev/null
+++ b/drivers/mtd/maps/physmap-gemini.c
@@ -0,0 +1,200 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Cortina Systems Gemini OF physmap add-on
+ * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org>
+ *
+ * This SoC has an elaborate flash control register, so we need to
+ * detect and set it up when booting on this platform.
+ */
+#include <linux/export.h>
+#include <linux/of.h>
+#include <linux/mtd/map.h>
+#include <linux/mtd/xip.h>
+#include <linux/mfd/syscon.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/bitops.h>
+#include <linux/pinctrl/consumer.h>
+#include "physmap-gemini.h"
+
+/*
+ * The Flash-relevant parts of the global status register
+ * These would also be relevant for a NAND driver.
+ */
+#define GLOBAL_STATUS			0x04
+#define FLASH_TYPE_MASK			(0x3 << 24)
+#define FLASH_TYPE_NAND_2K		(0x3 << 24)
+#define FLASH_TYPE_NAND_512		(0x2 << 24)
+#define FLASH_TYPE_PARALLEL		(0x1 << 24)
+#define FLASH_TYPE_SERIAL		(0x0 << 24)
+/* if parallel */
+#define FLASH_WIDTH_16BIT		(1 << 23)	/* else 8 bit */
+/* if serial */
+#define FLASH_ATMEL			(1 << 23)	/* else STM */
+
+#define FLASH_SIZE_MASK			(0x3 << 21)
+#define NAND_256M			(0x3 << 21)	/* and more */
+#define NAND_128M			(0x2 << 21)
+#define NAND_64M			(0x1 << 21)
+#define NAND_32M			(0x0 << 21)
+#define ATMEL_16M			(0x3 << 21)	/* and more */
+#define ATMEL_8M			(0x2 << 21)
+#define ATMEL_4M_2M			(0x1 << 21)
+#define ATMEL_1M			(0x0 << 21)	/* and less */
+#define STM_32M				(1 << 22)	/* and more */
+#define STM_16M				(0 << 22)	/* and less */
+
+#define FLASH_PARALLEL_HIGH_PIN_CNT	(1 << 20)	/* else low pin cnt */
+
+struct gemini_flash {
+	struct device *dev;
+	struct pinctrl *p;
+	struct pinctrl_state *enabled_state;
+	struct pinctrl_state *disabled_state;
+};
+
+/* Static local state */
+static struct gemini_flash *gf;
+
+static void gemini_flash_enable_pins(void)
+{
+	int ret;
+
+	if (IS_ERR(gf->enabled_state))
+		return;
+	ret = pinctrl_select_state(gf->p, gf->enabled_state);
+	if (ret)
+		dev_err(gf->dev, "failed to enable pins\n");
+}
+
+static void gemini_flash_disable_pins(void)
+{
+	int ret;
+
+	if (IS_ERR(gf->disabled_state))
+		return;
+	ret = pinctrl_select_state(gf->p, gf->disabled_state);
+	if (ret)
+		dev_err(gf->dev, "failed to disable pins\n");
+}
+
+static map_word __xipram gemini_flash_map_read(struct map_info *map,
+					       unsigned long ofs)
+{
+	map_word ret;
+
+	gemini_flash_enable_pins();
+	ret = inline_map_read(map, ofs);
+	gemini_flash_disable_pins();
+
+	return ret;
+}
+
+static void __xipram gemini_flash_map_write(struct map_info *map,
+					    const map_word datum,
+					    unsigned long ofs)
+{
+	gemini_flash_enable_pins();
+	inline_map_write(map, datum, ofs);
+	gemini_flash_disable_pins();
+}
+
+static void __xipram gemini_flash_map_copy_from(struct map_info *map,
+						void *to, unsigned long from,
+						ssize_t len)
+{
+	gemini_flash_enable_pins();
+	inline_map_copy_from(map, to, from, len);
+	gemini_flash_disable_pins();
+}
+
+static void __xipram gemini_flash_map_copy_to(struct map_info *map,
+					      unsigned long to,
+					      const void *from, ssize_t len)
+{
+	gemini_flash_enable_pins();
+	inline_map_copy_to(map, to, from, len);
+	gemini_flash_disable_pins();
+}
+
+int of_flash_probe_gemini(struct platform_device *pdev,
+			  struct device_node *np,
+			  struct map_info *map)
+{
+	struct regmap *rmap;
+	struct device *dev = &pdev->dev;
+	u32 val;
+	int ret;
+
+	/* Multiplatform guard */
+	if (!of_device_is_compatible(np, "cortina,gemini-flash"))
+		return 0;
+
+	gf = devm_kzalloc(dev, sizeof(*gf), GFP_KERNEL);
+	if (!gf)
+		return -ENOMEM;
+	gf->dev = dev;
+
+	rmap = syscon_regmap_lookup_by_phandle(np, "syscon");
+	if (IS_ERR(rmap)) {
+		dev_err(dev, "no syscon\n");
+		return PTR_ERR(rmap);
+	}
+
+	ret = regmap_read(rmap, GLOBAL_STATUS, &val);
+	if (ret) {
+		dev_err(dev, "failed to read global status register\n");
+		return -ENODEV;
+	}
+	dev_dbg(dev, "global status reg: %08x\n", val);
+
+	/*
+	 * It would be contradictory if a physmap flash was NOT parallel.
+	 */
+	if ((val & FLASH_TYPE_MASK) != FLASH_TYPE_PARALLEL) {
+		dev_err(dev, "flash is not parallel\n");
+		return -ENODEV;
+	}
+
+	/*
+	 * Complain if DT data and hardware definition is different.
+	 */
+	if (val & FLASH_WIDTH_16BIT) {
+		if (map->bankwidth != 2)
+			dev_warn(dev, "flash hardware say flash is 16 bit wide but DT says it is %d bits wide\n",
+				 map->bankwidth * 8);
+	} else {
+		if (map->bankwidth != 1)
+			dev_warn(dev, "flash hardware say flash is 8 bit wide but DT says it is %d bits wide\n",
+				 map->bankwidth * 8);
+	}
+
+	gf->p = devm_pinctrl_get(dev);
+	if (IS_ERR(gf->p)) {
+		dev_err(dev, "no pinctrl handle\n");
+		ret = PTR_ERR(gf->p);
+		return ret;
+	}
+
+	gf->enabled_state = pinctrl_lookup_state(gf->p, "enabled");
+	if (IS_ERR(gf->enabled_state))
+		dev_err(dev, "no enabled pin control state\n");
+
+	gf->disabled_state = pinctrl_lookup_state(gf->p, "disabled");
+	if (IS_ERR(gf->disabled_state)) {
+		dev_err(dev, "no disabled pin control state\n");
+	} else {
+		ret = pinctrl_select_state(gf->p, gf->disabled_state);
+		if (ret)
+			dev_err(gf->dev, "failed to disable pins\n");
+	}
+
+	map->read = gemini_flash_map_read;
+	map->write = gemini_flash_map_write;
+	map->copy_from = gemini_flash_map_copy_from;
+	map->copy_to = gemini_flash_map_copy_to;
+
+	dev_info(dev, "initialized Gemini-specific physmap control\n");
+
+	return 0;
+}