Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 493 insertions, 0 deletions

diff --git a/include/media/dvbdev.h b/include/media/dvbdev.h
new file mode 100644
index 000000000..e5a00d126
--- /dev/null
+++ b/include/media/dvbdev.h
@@ -0,0 +1,493 @@
+/*
+ * dvbdev.h
+ *
+ * Copyright (C) 2000 Ralph Metzler & Marcus Metzler
+ *                    for convergence integrated media GmbH
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Lesser Public License
+ * as published by the Free Software Foundation; either version 2.1
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#ifndef _DVBDEV_H_
+#define _DVBDEV_H_
+
+#include <linux/types.h>
+#include <linux/poll.h>
+#include <linux/fs.h>
+#include <linux/list.h>
+#include <media/media-device.h>
+
+#define DVB_MAJOR 212
+
+#if defined(CONFIG_DVB_MAX_ADAPTERS) && CONFIG_DVB_MAX_ADAPTERS > 0
+  #define DVB_MAX_ADAPTERS CONFIG_DVB_MAX_ADAPTERS
+#else
+  #define DVB_MAX_ADAPTERS 16
+#endif
+
+#define DVB_UNSET (-1)
+
+/* List of DVB device types */
+
+/**
+ * enum dvb_device_type - type of the Digital TV device
+ *
+ * @DVB_DEVICE_SEC:		Digital TV standalone Common Interface (CI)
+ * @DVB_DEVICE_FRONTEND:	Digital TV frontend.
+ * @DVB_DEVICE_DEMUX:		Digital TV demux.
+ * @DVB_DEVICE_DVR:		Digital TV digital video record (DVR).
+ * @DVB_DEVICE_CA:		Digital TV Conditional Access (CA).
+ * @DVB_DEVICE_NET:		Digital TV network.
+ *
+ * @DVB_DEVICE_VIDEO:		Digital TV video decoder.
+ *				Deprecated. Used only on av7110-av.
+ * @DVB_DEVICE_AUDIO:		Digital TV audio decoder.
+ *				Deprecated. Used only on av7110-av.
+ * @DVB_DEVICE_OSD:		Digital TV On Screen Display (OSD).
+ *				Deprecated. Used only on av7110.
+ */
+enum dvb_device_type {
+	DVB_DEVICE_SEC,
+	DVB_DEVICE_FRONTEND,
+	DVB_DEVICE_DEMUX,
+	DVB_DEVICE_DVR,
+	DVB_DEVICE_CA,
+	DVB_DEVICE_NET,
+
+	DVB_DEVICE_VIDEO,
+	DVB_DEVICE_AUDIO,
+	DVB_DEVICE_OSD,
+};
+
+#define DVB_DEFINE_MOD_OPT_ADAPTER_NR(adapter_nr) \
+	static short adapter_nr[] = \
+		{[0 ... (DVB_MAX_ADAPTERS - 1)] = DVB_UNSET }; \
+	module_param_array(adapter_nr, short, NULL, 0444); \
+	MODULE_PARM_DESC(adapter_nr, "DVB adapter numbers")
+
+struct dvb_frontend;
+
+/**
+ * struct dvb_adapter - represents a Digital TV adapter using Linux DVB API
+ *
+ * @num:		Number of the adapter
+ * @list_head:		List with the DVB adapters
+ * @device_list:	List with the DVB devices
+ * @name:		Name of the adapter
+ * @proposed_mac:	proposed MAC address for the adapter
+ * @priv:		private data
+ * @device:		pointer to struct device
+ * @module:		pointer to struct module
+ * @mfe_shared:		indicates mutually exclusive frontends.
+ *			1 = legacy exclusion behavior: blocking any open() call
+ *			2 = enhanced exclusion behavior, emulating the standard
+ *			behavior of busy frontends: allowing read-only sharing
+ *			and otherwise returning immediately with -EBUSY when any
+ *			of the frontends is already opened with write access.
+ * @mfe_dvbdev:		Frontend device in use, in the case of MFE
+ * @mfe_lock:		Lock to prevent using the other frontends when MFE is
+ *			used.
+ * @mdev_lock:          Protect access to the mdev pointer.
+ * @mdev:		pointer to struct media_device, used when the media
+ *			controller is used.
+ * @conn:		RF connector. Used only if the device has no separate
+ *			tuner.
+ * @conn_pads:		pointer to struct media_pad associated with @conn;
+ */
+struct dvb_adapter {
+	int num;
+	struct list_head list_head;
+	struct list_head device_list;
+	const char *name;
+	u8 proposed_mac [6];
+	void* priv;
+
+	struct device *device;
+
+	struct module *module;
+
+	int mfe_shared;			/* indicates mutually exclusive frontends */
+	struct dvb_device *mfe_dvbdev;	/* frontend device in use */
+	struct mutex mfe_lock;		/* access lock for thread creation */
+
+#if defined(CONFIG_MEDIA_CONTROLLER_DVB)
+	struct mutex mdev_lock;
+	struct media_device *mdev;
+	struct media_entity *conn;
+	struct media_pad *conn_pads;
+#endif
+};
+
+/**
+ * struct dvb_device - represents a DVB device node
+ *
+ * @list_head:	List head with all DVB devices
+ * @ref:	reference count for this device
+ * @fops:	pointer to struct file_operations
+ * @adapter:	pointer to the adapter that holds this device node
+ * @type:	type of the device, as defined by &enum dvb_device_type.
+ * @minor:	devnode minor number. Major number is always DVB_MAJOR.
+ * @id:		device ID number, inside the adapter
+ * @readers:	Initialized by the caller. Each call to open() in Read Only mode
+ *		decreases this counter by one.
+ * @writers:	Initialized by the caller. Each call to open() in Read/Write
+ *		mode decreases this counter by one.
+ * @users:	Initialized by the caller. Each call to open() in any mode
+ *		decreases this counter by one.
+ * @wait_queue:	wait queue, used to wait for certain events inside one of
+ *		the DVB API callers
+ * @kernel_ioctl: callback function used to handle ioctl calls from userspace.
+ * @name:	Name to be used for the device at the Media Controller
+ * @entity:	pointer to struct media_entity associated with the device node
+ * @pads:	pointer to struct media_pad associated with @entity;
+ * @priv:	private data
+ * @intf_devnode: Pointer to media_intf_devnode. Used by the dvbdev core to
+ *		store the MC device node interface
+ * @tsout_num_entities: Number of Transport Stream output entities
+ * @tsout_entity: array with MC entities associated to each TS output node
+ * @tsout_pads: array with the source pads for each @tsout_entity
+ *
+ * This structure is used by the DVB core (frontend, CA, net, demux) in
+ * order to create the device nodes. Usually, driver should not initialize
+ * this struct diretly.
+ */
+struct dvb_device {
+	struct list_head list_head;
+	struct kref ref;
+	const struct file_operations *fops;
+	struct dvb_adapter *adapter;
+	enum dvb_device_type type;
+	int minor;
+	u32 id;
+
+	/* in theory, 'users' can vanish now,
+	   but I don't want to change too much now... */
+	int readers;
+	int writers;
+	int users;
+
+	wait_queue_head_t	  wait_queue;
+	/* don't really need those !? -- FIXME: use video_usercopy  */
+	int (*kernel_ioctl)(struct file *file, unsigned int cmd, void *arg);
+
+	/* Needed for media controller register/unregister */
+#if defined(CONFIG_MEDIA_CONTROLLER_DVB)
+	const char *name;
+
+	/* Allocated and filled inside dvbdev.c */
+	struct media_intf_devnode *intf_devnode;
+
+	unsigned tsout_num_entities;
+	struct media_entity *entity, *tsout_entity;
+	struct media_pad *pads, *tsout_pads;
+#endif
+
+	void *priv;
+};
+
+/**
+ * struct dvbdevfops_node - fops nodes registered in dvbdevfops_list
+ *
+ * @fops:		Dynamically allocated fops for ->owner registration
+ * @type:		type of dvb_device
+ * @template:		dvb_device used for registration
+ * @list_head:		list_head for dvbdevfops_list
+ */
+struct dvbdevfops_node {
+	struct file_operations *fops;
+	enum dvb_device_type type;
+	const struct dvb_device *template;
+	struct list_head list_head;
+};
+
+/**
+ * dvb_device_get - Increase dvb_device reference
+ *
+ * @dvbdev:	pointer to struct dvb_device
+ */
+struct dvb_device *dvb_device_get(struct dvb_device *dvbdev);
+
+/**
+ * dvb_device_put - Decrease dvb_device reference
+ *
+ * @dvbdev:	pointer to struct dvb_device
+ */
+void dvb_device_put(struct dvb_device *dvbdev);
+
+/**
+ * dvb_register_adapter - Registers a new DVB adapter
+ *
+ * @adap:	pointer to struct dvb_adapter
+ * @name:	Adapter's name
+ * @module:	initialized with THIS_MODULE at the caller
+ * @device:	pointer to struct device that corresponds to the device driver
+ * @adapter_nums: Array with a list of the numbers for @dvb_register_adapter;
+ *		to select among them. Typically, initialized with:
+ *		DVB_DEFINE_MOD_OPT_ADAPTER_NR(adapter_nums)
+ */
+int dvb_register_adapter(struct dvb_adapter *adap, const char *name,
+			 struct module *module, struct device *device,
+			 short *adapter_nums);
+
+/**
+ * dvb_unregister_adapter - Unregisters a DVB adapter
+ *
+ * @adap:	pointer to struct dvb_adapter
+ */
+int dvb_unregister_adapter(struct dvb_adapter *adap);
+
+/**
+ * dvb_register_device - Registers a new DVB device
+ *
+ * @adap:	pointer to struct dvb_adapter
+ * @pdvbdev:	pointer to the place where the new struct dvb_device will be
+ *		stored
+ * @template:	Template used to create &pdvbdev;
+ * @priv:	private data
+ * @type:	type of the device, as defined by &enum dvb_device_type.
+ * @demux_sink_pads: Number of demux outputs, to be used to create the TS
+ *		outputs via the Media Controller.
+ */
+int dvb_register_device(struct dvb_adapter *adap,
+			struct dvb_device **pdvbdev,
+			const struct dvb_device *template,
+			void *priv,
+			enum dvb_device_type type,
+			int demux_sink_pads);
+
+/**
+ * dvb_remove_device - Remove a registered DVB device
+ *
+ * @dvbdev:	pointer to struct dvb_device
+ *
+ * This does not free memory. dvb_free_device() will do that when
+ * reference counter is empty
+ */
+void dvb_remove_device(struct dvb_device *dvbdev);
+
+
+/**
+ * dvb_unregister_device - Unregisters a DVB device
+ *
+ * @dvbdev:	pointer to struct dvb_device
+ */
+void dvb_unregister_device(struct dvb_device *dvbdev);
+
+#ifdef CONFIG_MEDIA_CONTROLLER_DVB
+/**
+ * dvb_create_media_graph - Creates media graph for the Digital TV part of the
+ *				device.
+ *
+ * @adap:			pointer to &struct dvb_adapter
+ * @create_rf_connector:	if true, it creates the RF connector too
+ *
+ * This function checks all DVB-related functions at the media controller
+ * entities and creates the needed links for the media graph. It is
+ * capable of working with multiple tuners or multiple frontends, but it
+ * won't create links if the device has multiple tuners and multiple frontends
+ * or if the device has multiple muxes. In such case, the caller driver should
+ * manually create the remaining links.
+ */
+__must_check int dvb_create_media_graph(struct dvb_adapter *adap,
+					bool create_rf_connector);
+
+/**
+ * dvb_register_media_controller - registers a media controller at DVB adapter
+ *
+ * @adap:			pointer to &struct dvb_adapter
+ * @mdev:			pointer to &struct media_device
+ */
+static inline void dvb_register_media_controller(struct dvb_adapter *adap,
+						 struct media_device *mdev)
+{
+	adap->mdev = mdev;
+}
+
+/**
+ * dvb_get_media_controller - gets the associated media controller
+ *
+ * @adap:			pointer to &struct dvb_adapter
+ */
+static inline struct media_device *
+dvb_get_media_controller(struct dvb_adapter *adap)
+{
+	return adap->mdev;
+}
+#else
+static inline
+int dvb_create_media_graph(struct dvb_adapter *adap,
+			   bool create_rf_connector)
+{
+	return 0;
+};
+#define dvb_register_media_controller(a, b) {}
+#define dvb_get_media_controller(a) NULL
+#endif
+
+/**
+ * dvb_generic_open - Digital TV open function, used by DVB devices
+ *
+ * @inode: pointer to &struct inode.
+ * @file: pointer to &struct file.
+ *
+ * Checks if a DVB devnode is still valid, and if the permissions are
+ * OK and increment negative use count.
+ */
+int dvb_generic_open(struct inode *inode, struct file *file);
+
+/**
+ * dvb_generic_release - Digital TV close function, used by DVB devices
+ *
+ * @inode: pointer to &struct inode.
+ * @file: pointer to &struct file.
+ *
+ * Checks if a DVB devnode is still valid, and if the permissions are
+ * OK and decrement negative use count.
+ */
+int dvb_generic_release(struct inode *inode, struct file *file);
+
+/**
+ * dvb_generic_ioctl - Digital TV close function, used by DVB devices
+ *
+ * @file: pointer to &struct file.
+ * @cmd: Ioctl name.
+ * @arg: Ioctl argument.
+ *
+ * Checks if a DVB devnode and struct dvbdev.kernel_ioctl is still valid.
+ * If so, calls dvb_usercopy().
+ */
+long dvb_generic_ioctl(struct file *file,
+		       unsigned int cmd, unsigned long arg);
+
+/**
+ * dvb_usercopy - copies data from/to userspace memory when an ioctl is
+ *      issued.
+ *
+ * @file: Pointer to struct &file.
+ * @cmd: Ioctl name.
+ * @arg: Ioctl argument.
+ * @func: function that will actually handle the ioctl
+ *
+ * Ancillary function that uses ioctl direction and size to copy from
+ * userspace. Then, it calls @func, and, if needed, data is copied back
+ * to userspace.
+ */
+int dvb_usercopy(struct file *file, unsigned int cmd, unsigned long arg,
+		 int (*func)(struct file *file, unsigned int cmd, void *arg));
+
+#if IS_ENABLED(CONFIG_I2C)
+
+struct i2c_adapter;
+struct i2c_client;
+/**
+ * dvb_module_probe - helper routine to probe an I2C module
+ *
+ * @module_name:
+ *	Name of the I2C module to be probed
+ * @name:
+ *	Optional name for the I2C module. Used for debug purposes.
+ * 	If %NULL, defaults to @module_name.
+ * @adap:
+ *	pointer to &struct i2c_adapter that describes the I2C adapter where
+ *	the module will be bound.
+ * @addr:
+ *	I2C address of the adapter, in 7-bit notation.
+ * @platform_data:
+ *	Platform data to be passed to the I2C module probed.
+ *
+ * This function binds an I2C device into the DVB core. Should be used by
+ * all drivers that use I2C bus to control the hardware. A module bound
+ * with dvb_module_probe() should use dvb_module_release() to unbind.
+ *
+ * Return:
+ *	On success, return an &struct i2c_client, pointing to the bound
+ *	I2C device. %NULL otherwise.
+ *
+ * .. note::
+ *
+ *    In the past, DVB modules (mainly, frontends) were bound via dvb_attach()
+ *    macro, with does an ugly hack, using I2C low level functions. Such
+ *    usage is deprecated and will be removed soon. Instead, use this routine.
+ */
+struct i2c_client *dvb_module_probe(const char *module_name,
+				    const char *name,
+				    struct i2c_adapter *adap,
+				    unsigned char addr,
+				    void *platform_data);
+
+/**
+ * dvb_module_release - releases an I2C device allocated with
+ *	 dvb_module_probe().
+ *
+ * @client: pointer to &struct i2c_client with the I2C client to be released.
+ *	    can be %NULL.
+ *
+ * This function should be used to free all resources reserved by
+ * dvb_module_probe() and unbinding the I2C hardware.
+ */
+void dvb_module_release(struct i2c_client *client);
+
+#endif /* CONFIG_I2C */
+
+/* Legacy generic DVB attach function. */
+#ifdef CONFIG_MEDIA_ATTACH
+
+/**
+ * dvb_attach - attaches a DVB frontend into the DVB core.
+ *
+ * @FUNCTION:	function on a frontend module to be called.
+ * @ARGS:	@FUNCTION arguments.
+ *
+ * This ancillary function loads a frontend module in runtime and runs
+ * the @FUNCTION function there, with @ARGS.
+ * As it increments symbol usage cont, at unregister, dvb_detach()
+ * should be called.
+ *
+ * .. note::
+ *
+ *    In the past, DVB modules (mainly, frontends) were bound via dvb_attach()
+ *    macro, with does an ugly hack, using I2C low level functions. Such
+ *    usage is deprecated and will be removed soon. Instead, you should use
+ *    dvb_module_probe().
+ */
+#define dvb_attach(FUNCTION, ARGS...) ({ \
+	void *__r = NULL; \
+	typeof(&FUNCTION) __a = symbol_request(FUNCTION); \
+	if (__a) { \
+		__r = (void *) __a(ARGS); \
+		if (__r == NULL) \
+			symbol_put(FUNCTION); \
+	} else { \
+		printk(KERN_ERR "DVB: Unable to find symbol "#FUNCTION"()\n"); \
+	} \
+	__r; \
+})
+
+/**
+ * dvb_detach - detaches a DVB frontend loaded via dvb_attach()
+ *
+ * @FUNC:	attach function
+ *
+ * Decrements usage count for a function previously called via dvb_attach().
+ */
+
+#define dvb_detach(FUNC)	symbol_put_addr(FUNC)
+
+#else
+#define dvb_attach(FUNCTION, ARGS...) ({ \
+	FUNCTION(ARGS); \
+})
+
+#define dvb_detach(FUNC)	{}
+
+#endif	/* CONFIG_MEDIA_ATTACH */
+
+#endif /* #ifndef _DVBDEV_H_ */