Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/gi…

…t/linville/wireless

Documentation/ABI/removed/o2cb

@@ -1,6 +1,6 @@
 What:		/sys/o2cb symlink
 Date:		May 2011
-KernelVersion:	2.6.40
+KernelVersion:	3.0
 Contact:	ocfs2-devel@oss.oracle.com
 Description:	This is a symlink: /sys/o2cb to /sys/fs/o2cb. The symlink is
 		removed when new versions of ocfs2-tools which know to look

Documentation/ABI/removed/raw1394

@@ -5,7 +5,7 @@ Description:
 	/dev/raw1394 was a character device file that allowed low-level
 	access to FireWire buses.  Its major drawbacks were its inability
 	to implement sensible device security policies, and its low level
-	of abstraction that required userspace clients do duplicate much
+	of abstraction that required userspace clients to duplicate much
 	of the kernel's ieee1394 core functionality.
 	Replaced by /dev/fw*, i.e. the <linux/firewire-cdev.h> ABI of
 	firewire-core.

Documentation/ABI/testing/evm

@@ -0,0 +1,23 @@
+What:		security/evm
+Date:		March 2011
+Contact:	Mimi Zohar <zohar@us.ibm.com>
+Description:
+		EVM protects a file's security extended attributes(xattrs)
+		against integrity attacks. The initial method maintains an
+		HMAC-sha1 value across the extended attributes, storing the
+		value as the extended attribute 'security.evm'.
+
+		EVM depends on the Kernel Key Retention System to provide it
+		with a trusted/encrypted key for the HMAC-sha1 operation.
+		The key is loaded onto the root's keyring using keyctl.  Until
+		EVM receives notification that the key has been successfully
+		loaded onto the keyring (echo 1 > <securityfs>/evm), EVM
+		can not create or validate the 'security.evm' xattr, but
+		returns INTEGRITY_UNKNOWN.  Loading the key and signaling EVM
+		should be done as early as possible.  Normally this is done
+		in the initramfs, which has already been measured as part
+		of the trusted boot.  For more information on creating and
+		loading existing trusted/encrypted keys, refer to:
+		Documentation/keys-trusted-encrypted.txt.  (A sample dracut
+		patch, which loads the trusted/encrypted key and enables
+		EVM, is available from http://linux-ima.sourceforge.net/#EVM.)

Documentation/ABI/testing/sysfs-bus-bcma

@@ -1,30 +1,30 @@
 What:		/sys/bus/bcma/devices/.../manuf
 Date:		May 2011
-KernelVersion:	2.6.40
+KernelVersion:	3.0
 Contact:	Rafał Miłecki <zajec5@gmail.com>
 Description:
 		Each BCMA core has it's manufacturer id. See
 		include/linux/bcma/bcma.h for possible values.
 
 What:		/sys/bus/bcma/devices/.../id
 Date:		May 2011
-KernelVersion:	2.6.40
+KernelVersion:	3.0
 Contact:	Rafał Miłecki <zajec5@gmail.com>
 Description:
 		There are a few types of BCMA cores, they can be identified by
 		id field.
 
 What:		/sys/bus/bcma/devices/.../rev
 Date:		May 2011
-KernelVersion:	2.6.40
+KernelVersion:	3.0
 Contact:	Rafał Miłecki <zajec5@gmail.com>
 Description:
 		BCMA cores of the same type can still slightly differ depending
 		on their revision. Use it for detailed programming.
 
 What:		/sys/bus/bcma/devices/.../class
 Date:		May 2011
-KernelVersion:	2.6.40
+KernelVersion:	3.0
 Contact:	Rafał Miłecki <zajec5@gmail.com>
 Description:
 		Each BCMA core is identified by few fields, including class it

Documentation/ABI/testing/sysfs-bus-pci-drivers-ehci_hcd

@@ -0,0 +1,46 @@
+What:		/sys/bus/pci/drivers/ehci_hcd/.../companion
+		/sys/bus/usb/devices/usbN/../companion
+Date:		January 2007
+KernelVersion:	2.6.21
+Contact:	Alan Stern <stern@rowland.harvard.edu>
+Description:
+		PCI-based EHCI USB controllers (i.e., high-speed USB-2.0
+		controllers) are often implemented along with a set of
+		"companion" full/low-speed USB-1.1 controllers.  When a
+		high-speed device is plugged in, the connection is routed
+		to the EHCI controller; when a full- or low-speed device
+		is plugged in, the connection is routed to the companion
+		controller.
+
+		Sometimes you want to force a high-speed device to connect
+		at full speed, which can be accomplished by forcing the
+		connection to be routed to the companion controller.
+		That's what this file does.  Writing a port number to the
+		file causes connections on that port to be routed to the
+		companion controller, and writing the negative of a port
+		number returns the port to normal operation.
+
+		For example: To force the high-speed device attached to
+		port 4 on bus 2 to run at full speed:
+
+			echo 4 >/sys/bus/usb/devices/usb2/../companion
+
+		To return the port to high-speed operation:
+
+			echo -4 >/sys/bus/usb/devices/usb2/../companion
+
+		Reading the file gives the list of ports currently forced
+		to the companion controller.
+
+		Note: Some EHCI controllers do not have companions; they
+		may contain an internal "transaction translator" or they
+		may be attached directly to a "rate-matching hub".  This
+		mechanism will not work with such controllers.  Also, it
+		cannot be used to force a port on a high-speed hub to
+		connect at full speed.
+
+		Note: When this file was first added, it appeared in a
+		different sysfs directory.  The location given above is
+		correct for 2.6.35 (and probably several earlier kernel
+		versions as well).
+

Documentation/ABI/testing/sysfs-bus-usb

@@ -142,3 +142,18 @@ Description:
 		such devices.
 Users:
 		usb_modeswitch
+
+What:		/sys/bus/usb/devices/.../power/usb2_hardware_lpm
+Date:		September 2011
+Contact:	Andiry Xu <andiry.xu@amd.com>
+Description:
+		If CONFIG_USB_SUSPEND is set and a USB 2.0 lpm-capable device
+		is plugged in to a xHCI host which support link PM, it will
+		perform a LPM test; if the test is passed and host supports
+		USB2 hardware LPM (xHCI 1.0 feature), USB2 hardware LPM will
+		be enabled for the device and the USB device directory will
+		contain a file named power/usb2_hardware_lpm.  The file holds
+		a string value (enable or disable) indicating whether or not
+		USB2 hardware LPM is enabled for the device. Developer can
+		write y/Y/1 or n/N/0 to the file to enable/disable the
+		feature.

Documentation/ABI/testing/sysfs-class-backlight-driver-adp8870

@@ -4,8 +4,8 @@ What:		/sys/class/backlight/<backlight>/l2_bright_max
 What:		/sys/class/backlight/<backlight>/l3_office_max
 What:		/sys/class/backlight/<backlight>/l4_indoor_max
 What:		/sys/class/backlight/<backlight>/l5_dark_max
-Date:		Mai 2011
-KernelVersion:	2.6.40
+Date:		May 2011
+KernelVersion:	3.0
 Contact:	device-drivers-devel@blackfin.uclinux.org
 Description:
 		Control the maximum brightness for <ambient light zone>
@@ -18,8 +18,8 @@ What:		/sys/class/backlight/<backlight>/l2_bright_dim
 What:		/sys/class/backlight/<backlight>/l3_office_dim
 What:		/sys/class/backlight/<backlight>/l4_indoor_dim
 What:		/sys/class/backlight/<backlight>/l5_dark_dim
-Date:		Mai 2011
-KernelVersion:	2.6.40
+Date:		May 2011
+KernelVersion:	3.0
 Contact:	device-drivers-devel@blackfin.uclinux.org
 Description:
 		Control the dim brightness for <ambient light zone>
@@ -29,8 +29,8 @@ Description:
 		this <ambient light zone>.
 
 What:		/sys/class/backlight/<backlight>/ambient_light_level
-Date:		Mai 2011
-KernelVersion:	2.6.40
+Date:		May 2011
+KernelVersion:	3.0
 Contact:	device-drivers-devel@blackfin.uclinux.org
 Description:
 		Get conversion value of the light sensor.
@@ -39,8 +39,8 @@ Description:
 		8000 (max ambient brightness)
 
 What:		/sys/class/backlight/<backlight>/ambient_light_zone
-Date:		Mai 2011
-KernelVersion:	2.6.40
+Date:		May 2011
+KernelVersion:	3.0
 Contact:	device-drivers-devel@blackfin.uclinux.org
 Description:
 		Get/Set current ambient light zone. Reading returns

Documentation/ABI/testing/sysfs-class-devfreq

@@ -0,0 +1,52 @@
+What:		/sys/class/devfreq/.../
+Date:		September 2011
+Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
+Description:
+		Provide a place in sysfs for the devfreq objects.
+		This allows accessing various devfreq specific variables.
+		The name of devfreq object denoted as ... is same as the
+		name of device using devfreq.
+
+What:		/sys/class/devfreq/.../governor
+Date:		September 2011
+Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
+Description:
+		The /sys/class/devfreq/.../governor shows the name of the
+		governor used by the corresponding devfreq object.
+
+What:		/sys/class/devfreq/.../cur_freq
+Date:		September 2011
+Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
+Description:
+		The /sys/class/devfreq/.../cur_freq shows the current
+		frequency of the corresponding devfreq object.
+
+What:		/sys/class/devfreq/.../central_polling
+Date:		September 2011
+Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
+Description:
+		The /sys/class/devfreq/.../central_polling shows whether
+		the devfreq ojbect is using devfreq-provided central
+		polling mechanism or not.
+
+What:		/sys/class/devfreq/.../polling_interval
+Date:		September 2011
+Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
+Description:
+		The /sys/class/devfreq/.../polling_interval shows and sets
+		the requested polling interval of the corresponding devfreq
+		object. The values are represented in ms. If the value is
+		less than 1 jiffy, it is considered to be 0, which means
+		no polling. This value is meaningless if the governor is
+		not polling; thus. If the governor is not using
+		devfreq-provided central polling
+		(/sys/class/devfreq/.../central_polling is 0), this value
+		may be useless.
+
+What:		/sys/class/devfreq/.../userspace/set_freq
+Date:		September 2011
+Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
+Description:
+		The /sys/class/devfreq/.../userspace/set_freq shows and
+		sets the requested frequency for the devfreq object if
+		userspace governor is in effect.

Documentation/ABI/testing/sysfs-driver-hid-logitech-lg4ff

@@ -0,0 +1,7 @@
+What:		/sys/module/hid_logitech/drivers/hid:logitech/<dev>/range.
+Date:		July 2011
+KernelVersion:	3.2
+Contact:	Michal Mal� <madcatxster@gmail.com>
+Description:	Display minimum, maximum and current range of the steering
+		wheel. Writing a value within min and max boundaries sets the
+		range of the wheel.

Documentation/DocBook/uio-howto.tmpl

@@ -529,7 +529,7 @@ memory (e.g. allocated with <function>kmalloc()</function>). There's also
 </para></listitem>
 
 <listitem><para>
-<varname>unsigned long addr</varname>: Required if the mapping is used.
+<varname>phys_addr_t addr</varname>: Required if the mapping is used.
 Fill in the address of your memory block. This address is the one that
 appears in sysfs.
 </para></listitem>

Documentation/PCI/pci.txt

@@ -314,7 +314,7 @@ from the PCI device config space. Use the values in the pci_dev structure
 as the PCI "bus address" might have been remapped to a "host physical"
 address by the arch/chip-set specific kernel support.
 
-See Documentation/IO-mapping.txt for how to access device registers
+See Documentation/io-mapping.txt for how to access device registers
 or device memory.
 
 The device driver needs to call pci_request_region() to verify

Documentation/RCU/NMI-RCU.txt

@@ -95,7 +95,7 @@ not to return until all ongoing NMI handlers exit.  It is therefore safe
 to free up the handler's data as soon as synchronize_sched() returns.
 
 Important note: for this to work, the architecture in question must
-invoke irq_enter() and irq_exit() on NMI entry and exit, respectively.
+invoke nmi_enter() and nmi_exit() on NMI entry and exit, respectively.
 
 
 Answer to Quick Quiz

Documentation/RCU/lockdep-splat.txt

@@ -0,0 +1,110 @@
+Lockdep-RCU was added to the Linux kernel in early 2010
+(http://lwn.net/Articles/371986/).  This facility checks for some common
+misuses of the RCU API, most notably using one of the rcu_dereference()
+family to access an RCU-protected pointer without the proper protection.
+When such misuse is detected, an lockdep-RCU splat is emitted.
+
+The usual cause of a lockdep-RCU slat is someone accessing an
+RCU-protected data structure without either (1) being in the right kind of
+RCU read-side critical section or (2) holding the right update-side lock.
+This problem can therefore be serious: it might result in random memory
+overwriting or worse.  There can of course be false positives, this
+being the real world and all that.
+
+So let's look at an example RCU lockdep splat from 3.0-rc5, one that
+has long since been fixed:
+
+===============================
+[ INFO: suspicious RCU usage. ]
+-------------------------------
+block/cfq-iosched.c:2776 suspicious rcu_dereference_protected() usage!
+
+other info that might help us debug this:
+
+
+rcu_scheduler_active = 1, debug_locks = 0
+3 locks held by scsi_scan_6/1552:
+ #0:  (&shost->scan_mutex){+.+.+.}, at: [<ffffffff8145efca>]
+scsi_scan_host_selected+0x5a/0x150
+ #1:  (&eq->sysfs_lock){+.+...}, at: [<ffffffff812a5032>]
+elevator_exit+0x22/0x60
+ #2:  (&(&q->__queue_lock)->rlock){-.-...}, at: [<ffffffff812b6233>]
+cfq_exit_queue+0x43/0x190
+
+stack backtrace:
+Pid: 1552, comm: scsi_scan_6 Not tainted 3.0.0-rc5 #17
+Call Trace:
+ [<ffffffff810abb9b>] lockdep_rcu_dereference+0xbb/0xc0
+ [<ffffffff812b6139>] __cfq_exit_single_io_context+0xe9/0x120
+ [<ffffffff812b626c>] cfq_exit_queue+0x7c/0x190
+ [<ffffffff812a5046>] elevator_exit+0x36/0x60
+ [<ffffffff812a802a>] blk_cleanup_queue+0x4a/0x60
+ [<ffffffff8145cc09>] scsi_free_queue+0x9/0x10
+ [<ffffffff81460944>] __scsi_remove_device+0x84/0xd0
+ [<ffffffff8145dca3>] scsi_probe_and_add_lun+0x353/0xb10
+ [<ffffffff817da069>] ? error_exit+0x29/0xb0
+ [<ffffffff817d98ed>] ? _raw_spin_unlock_irqrestore+0x3d/0x80
+ [<ffffffff8145e722>] __scsi_scan_target+0x112/0x680
+ [<ffffffff812c690d>] ? trace_hardirqs_off_thunk+0x3a/0x3c
+ [<ffffffff817da069>] ? error_exit+0x29/0xb0
+ [<ffffffff812bcc60>] ? kobject_del+0x40/0x40
+ [<ffffffff8145ed16>] scsi_scan_channel+0x86/0xb0
+ [<ffffffff8145f0b0>] scsi_scan_host_selected+0x140/0x150
+ [<ffffffff8145f149>] do_scsi_scan_host+0x89/0x90
+ [<ffffffff8145f170>] do_scan_async+0x20/0x160
+ [<ffffffff8145f150>] ? do_scsi_scan_host+0x90/0x90
+ [<ffffffff810975b6>] kthread+0xa6/0xb0
+ [<ffffffff817db154>] kernel_thread_helper+0x4/0x10
+ [<ffffffff81066430>] ? finish_task_switch+0x80/0x110
+ [<ffffffff817d9c04>] ? retint_restore_args+0xe/0xe
+ [<ffffffff81097510>] ? __init_kthread_worker+0x70/0x70
+ [<ffffffff817db150>] ? gs_change+0xb/0xb
+
+Line 2776 of block/cfq-iosched.c in v3.0-rc5 is as follows:
+
+	if (rcu_dereference(ioc->ioc_data) == cic) {
+
+This form says that it must be in a plain vanilla RCU read-side critical
+section, but the "other info" list above shows that this is not the
+case.  Instead, we hold three locks, one of which might be RCU related.
+And maybe that lock really does protect this reference.  If so, the fix
+is to inform RCU, perhaps by changing __cfq_exit_single_io_context() to
+take the struct request_queue "q" from cfq_exit_queue() as an argument,
+which would permit us to invoke rcu_dereference_protected as follows:
+
+	if (rcu_dereference_protected(ioc->ioc_data,
+				      lockdep_is_held(&q->queue_lock)) == cic) {
+
+With this change, there would be no lockdep-RCU splat emitted if this
+code was invoked either from within an RCU read-side critical section
+or with the ->queue_lock held.  In particular, this would have suppressed
+the above lockdep-RCU splat because ->queue_lock is held (see #2 in the
+list above).
+
+On the other hand, perhaps we really do need an RCU read-side critical
+section.  In this case, the critical section must span the use of the
+return value from rcu_dereference(), or at least until there is some
+reference count incremented or some such.  One way to handle this is to
+add rcu_read_lock() and rcu_read_unlock() as follows:
+
+	rcu_read_lock();
+	if (rcu_dereference(ioc->ioc_data) == cic) {
+		spin_lock(&ioc->lock);
+		rcu_assign_pointer(ioc->ioc_data, NULL);
+		spin_unlock(&ioc->lock);
+	}
+	rcu_read_unlock();
+
+With this change, the rcu_dereference() is always within an RCU
+read-side critical section, which again would have suppressed the
+above lockdep-RCU splat.
+
+But in this particular case, we don't actually deference the pointer
+returned from rcu_dereference().  Instead, that pointer is just compared
+to the cic pointer, which means that the rcu_dereference() can be replaced
+by rcu_access_pointer() as follows:
+
+	if (rcu_access_pointer(ioc->ioc_data) == cic) {
+
+Because it is legal to invoke rcu_access_pointer() without protection,
+this change would also suppress the above lockdep-RCU splat.