Commit Graph

20 Commits

Author SHA1 Message Date
Dmitry Torokhov e8b95728f7 Input: uinput - avoid FF flush when destroying device
Normally, when input device supporting force feedback effects is being
destroyed, we try to "flush" currently playing effects, so that the
physical device does not continue vibrating (or executing other effects).
Unfortunately this does not work well for uinput as flushing of the effects
deadlocks with the destroy action:

- if device is being destroyed because the file descriptor is being closed,
  then there is noone to even service FF requests;

- if device is being destroyed because userspace sent UI_DEV_DESTROY,
  while theoretically it could be possible to service FF requests,
  userspace is unlikely to do so (they'd need to make sure FF handling
  happens on a separate thread) even if kernel solves the issue with FF
  ioctls deadlocking with UI_DEV_DESTROY ioctl on udev->mutex.

To avoid lockups like the one below, let's install a custom input device
flush handler, and avoid trying to flush force feedback effects when we
destroying the device, and instead rely on uinput to shut off the device
properly.

NMI watchdog: Watchdog detected hard LOCKUP on cpu 3
...
 <<EOE>>  [<ffffffff817a0307>] _raw_spin_lock_irqsave+0x37/0x40
 [<ffffffff810e633d>] complete+0x1d/0x50
 [<ffffffffa00ba08c>] uinput_request_done+0x3c/0x40 [uinput]
 [<ffffffffa00ba587>] uinput_request_submit.part.7+0x47/0xb0 [uinput]
 [<ffffffffa00bb62b>] uinput_dev_erase_effect+0x5b/0x76 [uinput]
 [<ffffffff815d91ad>] erase_effect+0xad/0xf0
 [<ffffffff815d929d>] flush_effects+0x4d/0x90
 [<ffffffff815d4cc0>] input_flush_device+0x40/0x60
 [<ffffffff815daf1c>] evdev_cleanup+0xac/0xc0
 [<ffffffff815daf5b>] evdev_disconnect+0x2b/0x60
 [<ffffffff815d74ac>] __input_unregister_device+0xac/0x150
 [<ffffffff815d75f7>] input_unregister_device+0x47/0x70
 [<ffffffffa00bac45>] uinput_destroy_device+0xb5/0xc0 [uinput]
 [<ffffffffa00bb2de>] uinput_ioctl_handler.isra.9+0x65e/0x740 [uinput]
 [<ffffffff811231ab>] ? do_futex+0x12b/0xad0
 [<ffffffffa00bb3f8>] uinput_ioctl+0x18/0x20 [uinput]
 [<ffffffff81241248>] do_vfs_ioctl+0x298/0x480
 [<ffffffff81337553>] ? security_file_ioctl+0x43/0x60
 [<ffffffff812414a9>] SyS_ioctl+0x79/0x90
 [<ffffffff817a04ee>] entry_SYSCALL_64_fastpath+0x12/0x71

Reported-by: Rodrigo Rivas Costa <rodrigorivascosta@gmail.com>
Reported-by: Clément VUCHENER <clement.vuchener@gmail.com>
Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=193741
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2017-09-21 16:31:22 -07:00
Elias Vanderstuyft 33b96d9349 Input: document and check on implicitly defined FF_MAX_EFFECTS
There is an undocumented upper bound for the total number of ff effects:
    FF_GAIN (= 96).
This can be found as follows:
- user: write(EV_FF, effect_id, iterations)
    calls kernel: ff->playback(effect_id, ...): starts effect "effect_id"
- user: write(EV_FF, FF_GAIN, gain)
    calls kernel: ff->set_gain(gain, ...): sets gain

A collision occurs when effect_id equals FF_GAIN.
According to input_ff_event(),
FF_GAIN is the smallest value where a collision occurs.
Therefore the greatest safe value for effect_id is FF_GAIN - 1,
and thus the total number of effects should never exceed FF_GAIN.

Define FF_MAX_EFFECTS as FF_GAIN and check on this limit in ff-core.

Signed-off-by: Elias Vanderstuyft <elias.vds@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2015-10-16 15:32:16 -07:00
Dan Carpenter 379d7cfa9b Input: ff-core - silence an underflow warning
My static checker complains that "value" comes from the user in
evdev_do_ioctl() and we check that it's not too large here but we don't
check that it's negative.  It's harmless because the ->set_gain() and
->set_autocenter() functions truncate it to a valid u16 value, but we
may as well fix it just to make the static checker happy.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2015-09-29 16:09:36 -07:00
Anshul Garg 948cea1448 Input: ff-core - use for_each_set_bit where appropriate
Use for_each_set_bit to check for set bits in bitmap
as it is more efficient than checking individual bits.

Signed-off-by: Anshul Garg <aksgarg1989@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2015-07-08 21:50:59 -07:00
Shailendra Verma 4e3e4629e4 Input: ff-core - fix typo in comment to input_ff_erase()
Signed-off-by: Shailendra Verma <shailendra.capricorn@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2015-05-20 14:45:42 -07:00
Dan Murphy 8a4dda79a3 Input: ff-core - fix spelling mistake in ff-core
Fix spelling of magnitude
s/manginude/magnitude

Signed-off-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2015-05-08 16:35:58 -07:00
Oliver Neukum 2afebafdbd Input: ff-core - use new debug macros
Replace old pr_* with dev_* debugging macros

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2015-04-14 14:29:49 -07:00
Baodong Chen 41091ad0b8 Input: random formatting fixes
Fixes for some coding style issues reported by scripts/checkpatch.pl
utility.

Signed-off-by: Baodong Chen <chenbdchenbd@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2012-08-21 22:29:49 -07:00
Dan Carpenter 05be8b81aa Input: force feedback - potential integer wrap in input_ff_create()
The problem here is that max_effects can wrap on 32 bits systems.
We'd allocate a smaller amount of data than sizeof(struct ff_device).
The call to kcalloc() on the next line would fail but it would write
the NULL return outside of the memory we just allocated causing data
corruption.

The call path is that uinput_setup_device() get ->ff_effects_max from
the user and sets the value in the ->private_data struct.  From there
it is:
-> uinput_ioctl_handler()
   -> uinput_create_device()
      -> input_ff_create(dev, udev->ff_effects_max);

I've also changed ff_effects_max so it's an unsigned int instead of
a signed int as a cleanup.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2011-10-12 21:13:11 -07:00
Joe Perches da0c490115 Input: use pr_fmt and pr_<level>
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2010-11-30 23:10:26 -08:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Jari Vanhala 6a47081c37 Input: fix memory leak in force feedback core
Effects were allocated, but not freed anywhere.

Signed-off-by: Jari Vanhala <ext-jari.vanhala@nokia.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2009-12-04 22:16:38 -08:00
Dmitry Torokhov 467832032c Merge commit 'v2.6.32' into next 2009-12-02 23:38:13 -08:00
Roger Quadros 721a730ece Input: force feedback - fix function name in comment
Function name is input_ff_destroy() and not input_ff_free()

Signed-off-by: Roger Quadros <roger.quadros@nokia.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2009-11-23 08:51:48 -08:00
Dmitry Torokhov bf3204cbff Input: fix locking in memoryless force-feedback devices
Now that input core acquires dev->event_lock spinlock and disables
interrupts when propagating input events, using spin_lock_bh() in
ff-memless driver is not allowed. Actually, the timer_lock itself
is not needed anymore, we should simply use dev->event_lock
as well.

Also do a small cleanup in force-feedback core.

Reported-by: kerneloops.org
Reported-by: http://www.kerneloops.org/searchweek.php?search=ml_ff_set_gain
Reported-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2009-11-10 21:13:32 -08:00
Geert Uytterhoeven 83680cdbce drivers/input/ff-core.c needs <linux/sched.h>
Commit 656acd2bbc ("Input: fix locking in
force-feedback core") causes the following regression on m68k:

| linux/drivers/input/ff-core.c: In function 'input_ff_upload':
| linux/drivers/input/ff-core.c:172: error: dereferencing pointer to incomplete type
| linux/drivers/input/ff-core.c: In function 'erase_effect':
| linux/drivers/input/ff-core.c:197: error: dereferencing pointer to incomplete type
| linux/drivers/input/ff-core.c:204: error: dereferencing pointer to incomplete type
| make[4]: *** [drivers/input/ff-core.o] Error 1

As the incomplete type is `struct task_struct', including <linux/sched.h> fixes
it.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-02 18:40:08 -07:00
Dmitry Torokhov 656acd2bbc Input: fix locking in force-feedback core
The newly added event_lock spinlock in the input core disallows sleeping
and therefore using mutexes in event handlers. Convert force-feedback
core to rely on event_lock instead of mutex to protect slots allocated
for fore-feedback effects. The original mutex is still used to serialize
uploading and erasing of effects.

Reported-by: Anssi Hannula <anssi.hannula@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2008-06-30 09:26:02 -04:00
Dmitry Torokhov dec3eb01c2 Input: force feedback - make sure effect is present before playing
Make sure that requested effect id is not out of range for the
device and that effect is present before requesting device to
play it.

Reported-by: Jan Kratochvil <honza@jikos.cz>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2007-05-03 00:51:10 -04:00
Randy Dunlap e4477d2d1b Input: add to kernel-api docbook
Add input subsystem to kernel-api docbook.
Enhance some function and parameter comments.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2006-11-24 00:43:09 -05:00
Anssi Hannula 509ca1a938 Input: implement new force feedback interface
Implement a new force feedback interface, in which all non-driver-specific
operations are separated to a common module. This includes handling effect
type validations, locking, etc.

The effects are now file descriptor specific instead of the previous strange
half-process half-fd specific behaviour. The effect memory of devices is not
emptied if the root user opens and closes the device while another user is
using effects. This is a minor change and most likely no force feedback
aware programs are affected by this negatively.

Otherwise the userspace interface is left unaltered.

Signed-off-by: Anssi Hannula <anssi.hannula@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2006-07-19 01:40:22 -04:00