We have forgotten the rules of lock nesting: the irq-safe ones must be
taken inside the non-irq-safe ones, otherwise we are open to deadlock:

CPU0                          CPU1
----                          ----
lock(&(&pc->lock)->rlock);
                              local_irq_disable();
                              lock(&(&zone->lru_lock)->rlock);
                              lock(&(&pc->lock)->rlock);
<Interrupt>
lock(&(&zone->lru_lock)->rlock);

To check a different locking issue, I happened to add a spin_lock to
memcg's bit_spin_lock in lock_page_cgroup(), and lockdep very quickly
complained about __mem_cgroup_commit_charge_lrucare() (on CPU1 above).

So delete __mem_cgroup_commit_charge_lrucare(), passing a bool lrucare to
__mem_cgroup_commit_charge() instead, taking zone->lru_lock under
lock_page_cgroup() in the lrucare case.

The original was using spin_lock_irqsave, but we'd be in more trouble if
it were ever called at interrupt time: unconditional _irq is enough.  And
ClearPageLRU before del from lru, SetPageLRU before add to lru: no strong
reason, but that is the ordering used consistently elsewhere.

Fixes 36b62ad5 ("memcg: simplify corner case handling
of LRU").
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

If probing the RTC didn't succeed due to failed RTC register access, the
RTC device will be unregistered.  Then, when removing the module
r9701_remove() causes a kernel crash while trying to unregister a not
registered RTC device.  Fix this by doing RTC register access test before
RTC device registration.
Signed-off-by: Anatolij Gustschin <agust@denx.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

class_create() doesn't return a NULL, it only returns ERR_PTRs.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

class_create() never returns NULLs only ERR_PTRs.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Rodolfo Giometti <giometti@enneenne.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

check_hung_uninterruptible_tasks()->rcu_lock_break() introduced by
"softlockup: check all tasks in hung_task" commit ce9dbe24 looks
absolutely wrong.

	- rcu_lock_break() does put_task_struct(). If the task has exited
	  it is not safe to even read its ->state, nothing protects this
	  task_struct.

	- The TASK_DEAD checks are wrong too. Contrary to the comment, we
	  can't use it to check if the task was unhashed. It can be unhashed
	  without TASK_DEAD, or it can be valid with TASK_DEAD.

	  For example, an autoreaping task can do release_task(current)
	  long before it sets TASK_DEAD in do_exit().

	  Or, a zombie task can have ->state == TASK_DEAD but release_task()
	  was not called, and in this case we must not break the loop.

Change this code to check pid_alive() instead, and do this before we drop
the reference to the task_struct.

Note: while_each_thread() under rcu_read_lock() is not really safe, it can
livelock.  This will be fixed later, but fortunately in this case the
"max_count" logic saves us anyway.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Mandeep Singh Baines <msb@google.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Previously it was (ab)used by utrace.  Then it was wrongly used by the
scheduler code.

Currently it is not used, kill it before it finds the new erroneous user.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Now that CLONE_VFORK is killable, coredump_wait() no longer needs
complete_vfork_done().  zap_threads() should find and kill all tasks with
the same ->mm, this includes our parent if ->vfork_done is set.

mm_release() becomes the only caller, unexport complete_vfork_done().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Make vfork() killable.

Change do_fork(CLONE_VFORK) to do wait_for_completion_killable().  If it
fails we do not return to the user-mode and never touch the memory shared
with our child.

However, in this case we should clear child->vfork_done before return, we
use task_lock() in do_fork()->wait_for_vfork_done() and
complete_vfork_done() to serialize with each other.

Note: now that we use task_lock() we don't really need completion, we
could turn task->vfork_done into "task_struct *wake_up_me" but this needs
some complications.

NOTE: this and the next patches do not affect in-kernel users of
CLONE_VFORK, kernel threads run with all signals ignored including
SIGKILL/SIGSTOP.

However this is obviously the user-visible change.  Not only a fatal
signal can kill the vforking parent, a sub-thread can do execve or
exit_group() and kill the thread sleeping in vfork().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

No functional changes.

Move the clear-and-complete-vfork_done code into the new trivial helper,
complete_vfork_done().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Bart Van Assche reported a hung fio process when either hot-removing
storage or when interrupting the fio process itself.  The (pruned) call
trace for the latter looks like so:

  fio             D 0000000000000001     0  6849   6848 0x00000004
   ffff880092541b88 0000000000000046 ffff880000000000 ffff88012fa11dc0
   ffff88012404be70 ffff880092541fd8 ffff880092541fd8 ffff880092541fd8
   ffff880128b894d0 ffff88012404be70 ffff880092541b88 000000018106f24d
  Call Trace:
    schedule+0x3f/0x60
    io_schedule+0x8f/0xd0
    wait_for_all_aios+0xc0/0x100
    exit_aio+0x55/0xc0
    mmput+0x2d/0x110
    exit_mm+0x10d/0x130
    do_exit+0x671/0x860
    do_group_exit+0x44/0xb0
    get_signal_to_deliver+0x218/0x5a0
    do_signal+0x65/0x700
    do_notify_resume+0x65/0x80
    int_signal+0x12/0x17

The problem lies with the allocation batching code.  It will
opportunistically allocate kiocbs, and then trim back the list of iocbs
when there is not enough room in the completion ring to hold all of the
events.

In the case above, what happens is that the pruning back of events ends
up freeing up the last active request and the context is marked as dead,
so it is thus responsible for waking up waiters.  Unfortunately, the
code does not check for this condition, so we end up with a hung task.
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Reported-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Bart Van Assche <bvanassche@acm.org>
Cc: <stable@kernel.org>		[3.2.x only]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

register_kprobe() aborts if the address of the new request falls in a
prohibited area (such as ftrace pouch, __kprobes annotated functions,
non-kernel text addresses, jump label text).  We however don't return the
right error on this abort, resulting in a silent failure - incorrect
adding/reporting of kprobes ('perf probe do_fork+18' or 'perf probe
mcount' for instance).

In V2 we are incorporating Masami Hiramatsu's  feedback.

This patch fixes it by returning -EINVAL upon failure.

While we are here, rename the label used for exit to be more appropriate.
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Prashanth K Nageshappa <prashanth@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Since commit 04c6862c ("kmsg_dump: add kmsg_dump() calls to the
reboot, halt, poweroff and emergency_restart paths"), kmsg_dump() gets
run on normal paths including poweroff and reboot.

This is less than ideal given pstore implementations that can only
represent single backtraces, since a reboot may overwrite a stored oops
before it's been picked up by userspace.  In addition, some pstore
backends may have low performance and provide a significant delay in
reboot as a result.

This patch adds a printk.always_kmsg_dump kernel parameter (which can also
be changed from userspace).  Without it, the code will only be run on
failure paths rather than on normal paths.  The option can be enabled in
environments where there's a desire to attempt to audit whether or not a
reboot was cleanly requested or not.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Acked-by: Seiji Aguchi <seiji.aguchi@hds.com>
Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Marco Stornelli <marco.stornelli@gmail.com>
Cc: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Don Zickus <dzickus@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MMC fixes from Chris Ball for 3.3:
 - atmel-mci: oops fix against regression introduced in 3.2
 - core: power saving regression fix against 3.3-rc1
 - core: suspend/resume fix for UHS-I cards
 - esdhc-imx: MMC card regression fix against 3.0
 - mmci: oops fix for ARM systems with large (64k) pages
 - MAINTAINERS update for atmel-mci.

* tag 'mmc-fixes-for-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc:
  mmc: core: Fixup suspend/resume issues for UHS-I cards
  mmc: mmci: reduce max_blk_count to avoid overflowing max_req_size
  mmc: sdhci-esdhc-imx: fix for mmc cards on i.MX5
  mmc: core: fix regression: set default clock gating delay to 0
  MAINTAINERS: hand over atmel-mci (sd/mmc interface)
  mmc: atmel-mci: don't use dma features when using DMA with no chan available

Pull from Jiri Kosina:
 "Please pull to receive updates for HID layer.  Nikolai's patch is
  rather important and should still go in for 3.3, as it's a regression
  fix for commit b4b583d4."

* 'upstream-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid:
  HID: hid-input: allow array fields out of range
  HID: usbhid: Add NOGET quirk for the AIREN Slim+ keyboard

Allow array field values out of range as per HID 1.11 specification,
section 6.2.25:

	Rather than returning a single bit for each button in the group, an
	array returns an index in each field that corresponds to the pressed
	button (like keyboard scan codes). An out-of range value in and array
	field is considered no controls asserted.

Apparently, "and" above is a typo and should be "an".

This fixes at least Waltop tablet pen clicks - otherwise BTN_TOUCH is never
released.

The relevant part of Waltop tablet report descriptors is this:

	0x09, 0x42,         /*          Usage (Tip Switch),         */
	0x09, 0x44,         /*          Usage (Barrel Switch),      */
	0x09, 0x46,         /*          Usage (Tablet Pick),        */
	0x15, 0x01,         /*          Logical Minimum (1),        */
	0x25, 0x03,         /*          Logical Maximum (3),        */
	0x75, 0x04,         /*          Report Size (4),            */
	0x95, 0x01,         /*          Report Count (1),           */
	0x80,               /*          Input,                      */

This is a regression fix for commit b4b583d4 ("HID: be more strict when
ignoring out-of-range fields").
Signed-off-by: Nikolai Kondrashov <spbnick@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

MFD fixes from Samuel Ortiz:
 "This is the pull request for the MFD fixes for 3.3.  We have a few
  NULL pointer dereferences fixes, an ACPI conflict check fix, and a
  couple of wm8994 fixes."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/mfd-2.6:
  mfd: Correct readability of WM8994 DC servo 4E register
  mfd: Initialize tps65912 irq platform data properly
  mfd: Fix ACPI conflict check
  mfd: Fix ab8500 error path bug
  mfd: Test for jack detection when deciding if wm8994 should suspend
  mfd: Initialize tps65910 irq platform data properly
  mfd: Fix possible s5m null pointer dereference
  mfd: wm8350 variable dereferenced before check

It's only used inside fs/dcache.c, and we're going to play games with it
for the word-at-a-time patches.  This time we really don't even want to
export it, because it really is an internal function to fs/dcache.c, and
has been since it was introduced.

Having it in that extremely hot header file (it's included in pretty
much everything, thanks to <linux/fs.h>) is a disaster for testing
different versions, and is utterly pointless.

We really should have some kind of header file diet thing, where we
figure out which parts of header files are really better off private and
only result in more expensive compiles.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Even if cards supports 1.8V I/O voltage those should anyway be
initialized at 3.3V I/O according to (e)MMC, SD and SDIO specs.
Some eMMC and embedded SDIO devices are able to be initialized
at 1.8V as well, but it is better to be safe.

Do note that initialization in this context means that the card
has been completely powered off, otherwise the card will remain
at the last I/O voltage level that were negotitiated.

Due to the above being taken care of the suspend/resume issues
for UHS-I SD-cards has been fixed.
Signed-off-by: Ulf Hansson <ulf.hansson@stericsson.com>
Acked-by: Philip Rakity <prakity@marvell.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Chris Ball <cjb@laptop.org>

On a system with large pages (64k in my case), the following BUG is
triggered in MMC core:

[    2.338023] BUG: failure at drivers/mmc/core/core.c:221/mmc_start_request()!
[    2.338102] Kernel panic - not syncing: BUG!
[    2.338155] Call trace:
[    2.338228] [<ffffffc00008635c>] dump_backtrace+0x0/0x120
[    2.338317] [<ffffffc0003365ec>] dump_stack+0x14/0x1c
[    2.338403] [<ffffffc000336990>] panic+0xbc/0x1f0
[    2.338498] [<ffffffc00027a494>] mmc_start_request+0x154/0x184
[    2.338600] [<ffffffc00027abdc>] mmc_start_req+0x110/0x140
[    2.338701] [<ffffffc00028604c>] mmc_blk_issue_rw_rq+0x7c/0x39c
[    2.338804] [<ffffffc00028652c>] mmc_blk_issue_rq+0x1c0/0x468
[    2.338905] [<ffffffc000287564>] mmc_queue_thread+0x68/0x118
[    2.338995] [<ffffffc0000bc308>] kthread+0x84/0x8c

This is because of a 64k request with a max_req_size of 64k-1 bytes.

The following patch fixes the problem by limiting the max_blk_count
such that max_blk_count * max_blk_size == max_req_size. I couldn't
pursuade the compiler to emit a shift instead of a div without encoding
the shift explicitly.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

On i.MX53 we have to write a special SDHCI_CMD_ABORTCMD to the
SDHCI_TRANSFER_MODE register during a MMC_STOP_TRANSMISSION
command. This works for SD cards. However, with MMC cards
the MMC_SET_BLOCK_COUNT command is used instead, but this
needs the same handling. Fix MMC cards by testing for the
MMC_SET_BLOCK_COUNT command aswell. Tested on a custom i.MX53
board with a Transcend MMC+ card and eMMC.

The kernel started used MMC_SET_BLOCK_COUNT in 3.0, so this
is a regression for these boards introduced in 3.0; it should
go to 3.0/3.1/3.2-stable.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Chris Ball <cjb@laptop.org>

A recent commit "mmc: core: Use delayed work in clock gating framework"
(597dd9d7) introduced a default 200ms delay before clock gating
actually takes place.  This means that every time an MMC interface
becomes idle it first stays on for 200ms before gating its clock. This
leads to increased power consumption and is therefore a clear regression.
This patch restores the original behaviour by setting the default delay
to 0. Users prioritising throughput over power efficiency can still
modify the delay via sysfs.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Chris Ball <cjb@laptop.org>

Modify MAINTAINERS entry for Atmel SD/MMC drivers.
I hand the atmel-mci and at91_mci drivers over to Ludovic.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

SCSI fixes from James Bottomley:
 "There's just a single fix in here: the osd max device number fix."

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6:
  [SCSI] osd_uld: Bump MAX_OSD_DEVICES from 64 to 1,048,576

PARISC fixes from James Bottomley:
 "This is a set of build fixes to get the cross compiled architecture
  testbeds building again"

* tag 'parisc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/parisc-2.6:
  [PARISC] don't unconditionally override CROSS_COMPILE for 64 bit.
  [PARISC] include <linux/prefetch.h> in drivers/parisc/iommu-helpers.h
  [PARISC] fix compile break caused by iomap: make IOPORT/PCI mapping functions conditional

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/kvm: Fix Host-Only/Guest-Only counting with SVM disabled

Pull from Herbert Xu:
  "This push fixes a bug in mv_cesa that causes all hash operations
   that supply data on a final operation to fail."

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: mv_cesa - fix final callback not ignoring input data

Commit 5707c87f "vfs: uninline full_name_hash()" broke the modular
build, because it needs exporting now that it isn't inlined any more.
Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

hhwmon fixes for 3.3-rc6 from Guenter Roeck:

These patches are necessary for correct operation and management of
F75387.

* tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (f75375s) Catch some attempts to write to r/o registers
  hwmon: (f75375s) Properly map the F75387 automatic modes to pwm_enable
  hwmon: (f75375s) Make pwm*_mode writable for the F75387
  hwmon: (f75375s) Fix writes to the pwm* attribute for the F75387

fbdev fixes for 3.3 from Florian Tobias Schandinat

It includes:
 - two fixes for OMAP HDMI
 - one fix to make new OMAP functions behave as they are supposed to
 - one Kconfig dependency fix
 - two fixes for viafb for modesetting on VX900 hardware

* tag 'fbdev-fixes-for-3.3-2' of git://github.com/schandinat/linux-2.6:
  OMAPDSS: APPLY: make ovl_enable/disable synchronous
  OMAPDSS: panel-dvi: Add Kconfig dependency on I2C
  viafb: fix IGA1 modesetting on VX900
  viafb: select HW scaling on VX900 for IGA2
  OMAPDSS: HDMI: hot plug detect fix
  OMAPDSS: HACK: Ensure DSS clock domain gets out of idle when HDMI is enabled

sound fixes for 3.3-rc6 from Takashi Iwai

This contains again regression fixes for various HD-audio and ASoC
regarding SSI and dapm shutdown path.  In addition, a minor azt3328
fix and the correction of the new jack-notification strings in HD-audio.

* tag 'sound-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: hda - Kill hyphenated names
  ALSA: hda - Add a fake mute feature
  ALSA: hda - Always set HP pin in unsol handler for STAC/IDT codecs
  ALSA: azt3328 - Fix NULL ptr dereference on cards without OPL3
  ALSA: hda/realtek - Fix resume of multiple input sources
  ASoC: i.MX SSI: Fix DSP_A format.
  ASoC: dapm: Check for bias level when powering down

The code in link_path_walk() that finds out the length and the hash of
the next path component is some of the hottest code in the kernel.  And
I have a version of it that does things at the full width of the CPU
wordsize at a time, but that means that we *really* want to split it up
into a separate helper function.

So this re-organizes the code a bit and splits the hashing part into a
helper function called "hash_name()".  It returns the length of the
pathname component, while at the same time computing and writing the
hash to the appropriate location.

The code generation is slightly changed by this patch, but generally for
the better - and the added abstraction actually makes the code easier to
read too.  And the new interface is well suited for replacing just the
"hash_name()" function with alternative implementations.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

It did some odd things for unclear reasons.  As this is one of the
functions that gets changed when doing word-at-a-time compares, this is
yet another of the "don't change any semantics, but clean things up so
that subsequent patches don't get obscured by the cleanups".
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

.. and also use it in lookup_one_len() rather than open-coding it.

There aren't any performance-critical users, so inlining it is silly.
But it wouldn't matter if it wasn't for the fact that the word-at-a-time
dentry name patches want to conditionally replace the function, and
uninlining it sets the stage for that.

So again, this is a preparatory patch that doesn't change any semantics,
and only prepares for a much cleaner and testable word-at-a-time dentry
name accessor patch.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

These don't change any semantics, but they clean up the code a bit and
mark some arguments appropriately 'const'.

They came up as I was doing the word-at-a-time dcache name accessor
code, and cleaning this up now allows me to send out a smaller relevant
interesting patch for the experimental stuff.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Some callbacks are set too early -- i.e. we can have dma capabilities but
we can't get a dma channel. So wait to get the dma channel before setting
callbacks and change logs consequently.
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
[Should be applied to 3.2-stable.]
Cc: <stable@vger.kernel.org>
Signed-off-by: Chris Ball <cjb@laptop.org>

It makes no sense to attempt to manually configure the fan in auto mode,
or set the duty cycle directly in closed loop mode.  The corresponding
registers are then read-only.  If the user tries it nonetheless, error out
with EINVAL instead of silently doing nothing.
Signed-off-by: Nikolaus Schulz <mail@microschulz.de>
[guenter.roeck@ericsson.com: Minor formatting cleanup]
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>

The F75387 supports automatic fan control using either PWM duty cycle or
RPM speed values.  Make the driver detect the latter mode, and expose the
different modes in sysfs as per pwm_enable, so that the user can switch
between them.

The interpretation of the pwm_enable attribute for the F75387 is adjusted
to be a superset of those values used for similar Fintek chips which do
not support automatic duty mode, with 2 mapping to automatic speed mode,
and moving automatic duty mode to the new value 4.

Toggling the duty mode via pwm_enable is currently denied for the F75387,
as the chip then simply reinterprets the fan configuration register values
according to the new mode, switching between RPM and PWM units, which
makes this a dangerous operation.

This patch introduces a new pwm mode into the driver. This is necessary
because the new mode (automatic pwm mode, 4) may already be enabled by the
BIOS, and the driver should not break existing functionality. This was seen
on at least one board.
Signed-off-by: Nikolaus Schulz <mail@microschulz.de>
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>

Merge branches 'core-urgent-for-linus', 'perf-urgent-for-linus' and 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pulling latest branches from Ingo:

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  memblock: Fix size aligning of memblock_alloc_base_nid()

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf probe: Ensure offset provided is not greater than function length without DWARF info too
  perf tools: Ensure comm string is properly terminated
  perf probe: Ensure offset provided is not greater than function length
  perf evlist: Return first evsel for non-sample event on old kernel
  perf/hwbp: Fix a possible memory leak

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  CPU hotplug, cpusets, suspend: Don't touch cpusets during suspend/resume

There is only one error code to return for a bad user-space buffer
pointer passed to a system call in the same address space as the
system call is executed, and that is EFAULT.  Furthermore, the
low-level access routines, which catch most of the faults, return
EFAULT already.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@hack.frob.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>