linux-stable.git/drivers/staging, branch v3.11.2

staging: comedi: dt282x: dt282x_ai_insn_read() always fails

2013-09-27T00:21:38+00:00

commit 2c4283ca7cdcc6605859c836fc536fcd83a4525f upstream.

In dt282x_ai_insn_read() we call this macro like:
wait_for(!mux_busy(), comedi_error(dev, "timeout\n"); return -ETIME;);
Because the if statement doesn't have curly braces it means we always
return -ETIME and the function never succeeds.

Signed-off-by: Dan Carpenter 
Acked-by: Ian Abbott 
Signed-off-by: Greg Kroah-Hartman

zram: don't grab mutex in zram_slot_free_noity

2013-09-27T00:21:35+00:00

commit a0c516cbfc7452c8cbd564525fef66d9f20b46d1 upstream.

[1] introduced down_write in zram_slot_free_notify to prevent race
between zram_slot_free_notify and zram_bvec_[read|write]. The race
could happen if somebody who has right permission to open swap device
is reading swap device while it is used by swap in parallel.

However, zram_slot_free_notify is called with holding spin_lock of
swap layer so we shouldn't avoid holing mutex. Otherwise, lockdep
warns it.

This patch adds new list to handle free slot and workqueue
so zram_slot_free_notify just registers slot index to be freed and
registers the request to workqueue. If workqueue is expired,
it holds mutex_lock so there is no problem any more.

If any I/O is issued, zram handles pending slot-free request
caused by zram_slot_free_notify right before handling issued
request because workqueue wouldn't be expired yet so zram I/O
request handling function can miss it.

Lastly, when zram is reset, flush_work could handle all of pending
free request so we shouldn't have memory leak.

NOTE: If zram_slot_free_notify's kmalloc with GFP_ATOMIC would be
failed, the slot will be freed when next write I/O write the slot.

[1] [57ab0485, zram: use zram->lock to protect zram_free_page()
    in swap free notify path]

* from v2
  * refactoring

* from v1
  * totally redesign

Cc: Nitin Gupta 
Cc: Jiang Liu 
Signed-off-by: Minchan Kim 
Signed-off-by: Greg Kroah-Hartman

zram: fix invalid memory access

2013-09-27T00:21:23+00:00

commit 2b86ab9cc29fcd435cde9378c3b9ffe8b5c76128 upstream.

[1] tried to fix invalid memory access on zram->disk but it didn't
fix properly because get_disk failed during module exit path.

Actually, we don't need to reset zram->disk's capacity to zero
in module exit path so that this patch introduces new argument
"reset_capacity" on zram_reset_divice and it only reset it when
reset_store is called.

[1] 6030ea9b,  zram: avoid invalid memory access in zram_exit()

Cc: Nitin Gupta 
Cc: Jiang Liu 
Signed-off-by: Minchan Kim 
Signed-off-by: Greg Kroah-Hartman

imx-drm: imx-drm-core: Export imx_drm_encoder_get_mux_id

2013-09-14T14:06:46+00:00

commit ea8d15832016b0d07a8121159904e6b1d21b5b8b upstream.

When building imx_v6_v7_defconfig with imx-drm drivers selected as modules, we
get the following build error:

ERROR: "imx_drm_encoder_get_mux_id" [drivers/staging/imx-drm/imx-ldb.ko] undefined!

Export the required function to avoid this problem.

Signed-off-by: Fabio Estevam 
Acked-by: Sascha Hauer 
Acked-by: Philipp Zabel 
Cc: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman

staging: comedi: bug-fix NULL pointer dereference on failed attach

2013-08-23T17:31:47+00:00

Commit dcd7b8bd63cb81c5b973bf86510ca3c80bbbd162 ("staging: comedi: put
module _after_ detach" by myself) reversed a couple of calls in
`comedi_device_attach()` when recovering from an error returned by the
low-level driver's 'attach' handler.  Unfortunately, that introduced a
NULL pointer dereference bug as `dev->driver` is NULL after the call to
`comedi_device_detach()`.   We still have a pointer to the low-level
comedi driver structure in the `driv` variable, so use that instead.

Signed-off-by: Ian Abbott 
Cc:  # 3.10+
Signed-off-by: Greg Kroah-Hartman

staging: zcache: fix "zcache=" kernel parameter

2013-07-29T18:45:09+00:00

Commit 835f2f5 ("staging: zcache: enable zcache to be built/loaded as
a module") introduced an incorrect handling of "zcache=" parameter.

Inside zcache_comp_init() function, zcache_comp_name variable is
checked for being empty. If not empty, the above variable is tested
for being compatible with Crypto API. Unfortunately, after that
function ends unconditionally (by the "goto out" directive) and returns:
- non-zero value if verification succeeded, wrongly indicating an error
- zero value if verification failed, falsely informing that function
  zcache_comp_init() ended properly.

A solution to this problem is as following:
1. Move the "goto out" directive inside the "if (!ret)" statement
2. In case that crypto_has_comp() returned 0, change the value of ret
   to non-zero before "goto out" to indicate an error.

This patch replaces an earlier one from Michal Hocko (based on report
from Cristian Rodriguez):

	http://permalink.gmane.org/gmane.linux.kernel.mm/102484

It also addressed the same issue but didn't fix the zcache_comp_init()
for case when the compressor data passed to "zcache=" option was invalid
or unsupported.

Signed-off-by: Piotr Sarna 
[bzolnier: updated patch description]
Acked-by: Bartlomiej Zolnierkiewicz 
Signed-off-by: Kyungmin Park 
Acked-by: Konrad Rzeszutek Wilk 
Acked-by: Michal Hocko 
Cc: stable  # 3.10
Cc: Cristian Rodriguez 
Cc: Bob Liu 
Signed-off-by: Greg Kroah-Hartman

MAINTAINERS: Update the list of maintainers for staging/comedi driver.

2013-07-24T16:51:18+00:00

This patch updates the list of maintainers for the staging/comedi
driver.

Signed-off-by: Lidza Louina 
Acked-by: H Hartley Sweeten 
Acked-by: Ian Abbott 
Signed-off-by: Greg Kroah-Hartman

staging: tidspbridge: replace strict_strtol() with kstrtos32()

2013-07-24T16:51:18+00:00

The usage of strict_strtol() is not preferred, because
strict_strtol() is obsolete. Thus, kstrtos32() should be
used in order to convert a string to s32. Also, error handling
is added to get rid of a __must_check warning.

This fixes a memory corruption bug as well.

Signed-off-by: Jingoo Han 
Reviewed-by: Dan Carpenter 
Signed-off-by: Greg Kroah-Hartman

staging: android: logger: Correct write offset reset on error

2013-07-23T22:08:50+00:00

In the situation that a writer fails to copy data from userspace it will reset
the write offset to the value it had before it went to sleep. This discarding
any messages written while aquiring the mutex.

Therefore the reset offset needs to be retrieved after acquiring the mutex.

Cc: Android Kernel Team 
Signed-off-by: Bjorn Andersson 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

staging: zram: protect zram_reset_device() call

2013-07-23T22:08:50+00:00

Commit 9b3bb7abcdf2df0f1b2657e6cbc9d06bc2b3b36f (remove
zram_sysfs file (v2)) accidentally made zram_reset_device()
racy. Protect zram_reset_device() call with zram->lock.

Signed-off-by: Sergey Senozhatsky 
Acked-by: Jerome Marchand 
Signed-off-by: Greg Kroah-Hartman