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, 349 insertions, 0 deletions

diff --git a/drivers/edac/edac_device.h b/drivers/edac/edac_device.h
new file mode 100644
index 000000000..24c1921aa
--- /dev/null
+++ b/drivers/edac/edac_device.h
@@ -0,0 +1,349 @@
+/*
+ * Defines, structures, APIs for edac_device
+ *
+ * (C) 2007 Linux Networx (http://lnxi.com)
+ * This file may be distributed under the terms of the
+ * GNU General Public License.
+ *
+ * Written by Thayne Harbaugh
+ * Based on work by Dan Hollis <goemon at anime dot net> and others.
+ *	http://www.anime.net/~goemon/linux-ecc/
+ *
+ * NMI handling support added by
+ *     Dave Peterson <dsp@llnl.gov> <dave_peterson@pobox.com>
+ *
+ * Refactored for multi-source files:
+ *	Doug Thompson <norsk5@xmission.com>
+ *
+ * Please look at Documentation/driver-api/edac.rst for more info about
+ * EDAC core structs and functions.
+ */
+
+#ifndef _EDAC_DEVICE_H_
+#define _EDAC_DEVICE_H_
+
+#include <linux/device.h>
+#include <linux/edac.h>
+#include <linux/kobject.h>
+#include <linux/list.h>
+#include <linux/types.h>
+#include <linux/sysfs.h>
+#include <linux/workqueue.h>
+
+
+/*
+ * The following are the structures to provide for a generic
+ * or abstract 'edac_device'. This set of structures and the
+ * code that implements the APIs for the same, provide for
+ * registering EDAC type devices which are NOT standard memory.
+ *
+ * CPU caches (L1 and L2)
+ * DMA engines
+ * Core CPU switches
+ * Fabric switch units
+ * PCIe interface controllers
+ * other EDAC/ECC type devices that can be monitored for
+ * errors, etc.
+ *
+ * It allows for a 2 level set of hierarchy. For example:
+ *
+ * cache could be composed of L1, L2 and L3 levels of cache.
+ * Each CPU core would have its own L1 cache, while sharing
+ * L2 and maybe L3 caches.
+ *
+ * View them arranged, via the sysfs presentation:
+ * /sys/devices/system/edac/..
+ *
+ *	mc/		<existing memory device directory>
+ *	cpu/cpu0/..	<L1 and L2 block directory>
+ *		/L1-cache/ce_count
+ *			 /ue_count
+ *		/L2-cache/ce_count
+ *			 /ue_count
+ *	cpu/cpu1/..	<L1 and L2 block directory>
+ *		/L1-cache/ce_count
+ *			 /ue_count
+ *		/L2-cache/ce_count
+ *			 /ue_count
+ *	...
+ *
+ *	the L1 and L2 directories would be "edac_device_block's"
+ */
+
+struct edac_device_counter {
+	u32 ue_count;
+	u32 ce_count;
+};
+
+/* forward reference */
+struct edac_device_ctl_info;
+struct edac_device_block;
+
+/* edac_dev_sysfs_attribute structure
+ *	used for driver sysfs attributes in mem_ctl_info
+ *	for extra controls and attributes:
+ *		like high level error Injection controls
+ */
+struct edac_dev_sysfs_attribute {
+	struct attribute attr;
+	ssize_t (*show)(struct edac_device_ctl_info *, char *);
+	ssize_t (*store)(struct edac_device_ctl_info *, const char *, size_t);
+};
+
+/* edac_dev_sysfs_block_attribute structure
+ *
+ *	used in leaf 'block' nodes for adding controls/attributes
+ *
+ *	each block in each instance of the containing control structure can
+ *	have an array of the following. The show function will be filled in
+ *	with the show function in the low level driver.
+ */
+struct edac_dev_sysfs_block_attribute {
+	struct attribute attr;
+	ssize_t (*show)(struct kobject *, struct attribute *, char *);
+};
+
+/* device block control structure */
+struct edac_device_block {
+	struct edac_device_instance *instance;	/* Up Pointer */
+	char name[EDAC_DEVICE_NAME_LEN + 1];
+
+	struct edac_device_counter counters;	/* basic UE and CE counters */
+
+	int nr_attribs;		/* how many attributes */
+
+	/* this block's attributes, could be NULL */
+	struct edac_dev_sysfs_block_attribute *block_attributes;
+
+	/* edac sysfs device control */
+	struct kobject kobj;
+};
+
+/* device instance control structure */
+struct edac_device_instance {
+	struct edac_device_ctl_info *ctl;	/* Up pointer */
+	char name[EDAC_DEVICE_NAME_LEN + 4];
+
+	struct edac_device_counter counters;	/* instance counters */
+
+	u32 nr_blocks;		/* how many blocks */
+	struct edac_device_block *blocks;	/* block array */
+
+	/* edac sysfs device control */
+	struct kobject kobj;
+};
+
+
+/*
+ * Abstract edac_device control info structure
+ *
+ */
+struct edac_device_ctl_info {
+	/* for global list of edac_device_ctl_info structs */
+	struct list_head link;
+
+	struct module *owner;	/* Module owner of this control struct */
+
+	int dev_idx;
+
+	/* Per instance controls for this edac_device */
+	int log_ue;		/* boolean for logging UEs */
+	int log_ce;		/* boolean for logging CEs */
+	int panic_on_ue;	/* boolean for panic'ing on an UE */
+	unsigned poll_msec;	/* number of milliseconds to poll interval */
+	unsigned long delay;	/* number of jiffies for poll_msec */
+
+	/* Additional top controller level attributes, but specified
+	 * by the low level driver.
+	 *
+	 * Set by the low level driver to provide attributes at the
+	 * controller level, same level as 'ue_count' and 'ce_count' above.
+	 * An array of structures, NULL terminated
+	 *
+	 * If attributes are desired, then set to array of attributes
+	 * If no attributes are desired, leave NULL
+	 */
+	const struct edac_dev_sysfs_attribute *sysfs_attributes;
+
+	/* pointer to main 'edac' subsys in sysfs */
+	const struct bus_type *edac_subsys;
+
+	/* the internal state of this controller instance */
+	int op_state;
+	/* work struct for this instance */
+	struct delayed_work work;
+
+	/* pointer to edac polling checking routine:
+	 *      If NOT NULL: points to polling check routine
+	 *      If NULL: Then assumes INTERRUPT operation, where
+	 *              MC driver will receive events
+	 */
+	void (*edac_check) (struct edac_device_ctl_info * edac_dev);
+
+	struct device *dev;	/* pointer to device structure */
+
+	const char *mod_name;	/* module name */
+	const char *ctl_name;	/* edac controller  name */
+	const char *dev_name;	/* pci/platform/etc... name */
+
+	void *pvt_info;		/* pointer to 'private driver' info */
+
+	unsigned long start_time;	/* edac_device load start time (jiffies) */
+
+	/* sysfs top name under 'edac' directory
+	 * and instance name:
+	 *      cpu/cpu0/...
+	 *      cpu/cpu1/...
+	 *      cpu/cpu2/...
+	 *      ...
+	 */
+	char name[EDAC_DEVICE_NAME_LEN + 1];
+
+	/* Number of instances supported on this control structure
+	 * and the array of those instances
+	 */
+	u32 nr_instances;
+	struct edac_device_instance *instances;
+	struct edac_device_block *blocks;
+
+	/* Event counters for the this whole EDAC Device */
+	struct edac_device_counter counters;
+
+	/* edac sysfs device control for the 'name'
+	 * device this structure controls
+	 */
+	struct kobject kobj;
+};
+
+/* To get from the instance's wq to the beginning of the ctl structure */
+#define to_edac_mem_ctl_work(w) \
+		container_of(w, struct mem_ctl_info, work)
+
+#define to_edac_device_ctl_work(w) \
+		container_of(w,struct edac_device_ctl_info,work)
+
+/*
+ * The alloc() and free() functions for the 'edac_device' control info
+ * structure. A MC driver will allocate one of these for each edac_device
+ * it is going to control/register with the EDAC CORE.
+ */
+extern struct edac_device_ctl_info *edac_device_alloc_ctl_info(
+		unsigned sizeof_private,
+		char *edac_device_name, unsigned nr_instances,
+		char *edac_block_name, unsigned nr_blocks,
+		unsigned offset_value,
+		int device_index);
+
+/* The offset value can be:
+ *	-1 indicating no offset value
+ *	0 for zero-based block numbers
+ *	1 for 1-based block number
+ *	other for other-based block number
+ */
+#define	BLOCK_OFFSET_VALUE_OFF	((unsigned) -1)
+
+extern void edac_device_free_ctl_info(struct edac_device_ctl_info *ctl_info);
+
+/**
+ * edac_device_add_device - Insert the 'edac_dev' structure into the
+ *	 edac_device global list and create sysfs entries associated with
+ *	 edac_device structure.
+ *
+ * @edac_dev: pointer to edac_device structure to be added to the list
+ *	'edac_device' structure.
+ *
+ * Returns:
+ *	0 on Success, or an error code on failure
+ */
+extern int edac_device_add_device(struct edac_device_ctl_info *edac_dev);
+
+/**
+ * edac_device_del_device - Remove sysfs entries for specified edac_device
+ *	structure and then remove edac_device structure from global list
+ *
+ * @dev:
+ *	Pointer to struct &device representing the edac device
+ *	structure to remove.
+ *
+ * Returns:
+ *	Pointer to removed edac_device structure,
+ *	or %NULL if device not found.
+ */
+extern struct edac_device_ctl_info *edac_device_del_device(struct device *dev);
+
+/**
+ * edac_device_handle_ce_count - Log correctable errors.
+ *
+ * @edac_dev: pointer to struct &edac_device_ctl_info
+ * @inst_nr: number of the instance where the CE error happened
+ * @count: Number of errors to log.
+ * @block_nr: number of the block where the CE error happened
+ * @msg: message to be printed
+ */
+void edac_device_handle_ce_count(struct edac_device_ctl_info *edac_dev,
+				 unsigned int count, int inst_nr, int block_nr,
+				 const char *msg);
+
+/**
+ * edac_device_handle_ue_count - Log uncorrectable errors.
+ *
+ * @edac_dev: pointer to struct &edac_device_ctl_info
+ * @inst_nr: number of the instance where the CE error happened
+ * @count: Number of errors to log.
+ * @block_nr: number of the block where the CE error happened
+ * @msg: message to be printed
+ */
+void edac_device_handle_ue_count(struct edac_device_ctl_info *edac_dev,
+				 unsigned int count, int inst_nr, int block_nr,
+				 const char *msg);
+
+/**
+ * edac_device_handle_ce(): Log a single correctable error
+ *
+ * @edac_dev: pointer to struct &edac_device_ctl_info
+ * @inst_nr: number of the instance where the CE error happened
+ * @block_nr: number of the block where the CE error happened
+ * @msg: message to be printed
+ */
+static inline void
+edac_device_handle_ce(struct edac_device_ctl_info *edac_dev, int inst_nr,
+		      int block_nr, const char *msg)
+{
+	edac_device_handle_ce_count(edac_dev, 1, inst_nr, block_nr, msg);
+}
+
+/**
+ * edac_device_handle_ue(): Log a single uncorrectable error
+ *
+ * @edac_dev: pointer to struct &edac_device_ctl_info
+ * @inst_nr: number of the instance where the UE error happened
+ * @block_nr: number of the block where the UE error happened
+ * @msg: message to be printed
+ */
+static inline void
+edac_device_handle_ue(struct edac_device_ctl_info *edac_dev, int inst_nr,
+		      int block_nr, const char *msg)
+{
+	edac_device_handle_ue_count(edac_dev, 1, inst_nr, block_nr, msg);
+}
+
+/**
+ * edac_device_alloc_index: Allocate a unique device index number
+ *
+ * Returns:
+ *	allocated index number
+ */
+extern int edac_device_alloc_index(void);
+extern const char *edac_layer_name[];
+
+/* Free the actual struct */
+static inline void __edac_device_free_ctl_info(struct edac_device_ctl_info *ci)
+{
+	if (ci) {
+		kfree(ci->pvt_info);
+		kfree(ci->blocks);
+		kfree(ci->instances);
+		kfree(ci);
+	}
+}
+#endif