linux-stable.git/drivers/dma, branch v4.9.78

dmaengine: ti-dma-crossbar: Correct am335x/am43xx mux value type

2017-12-20T09:07:27+00:00

[ Upstream commit 288e7560e4d3e259aa28f8f58a8dfe63627a1bf6 ]

The used 0x1f mask is only valid for am335x family of SoC, different family
using this type of crossbar might have different number of electable
events. In case of am43xx family 0x3f mask should have been used for
example.
Instead of trying to handle each family's mask, just use u8 type to store
the mux value since the event offsets are aligned to byte offset.

Fixes: 42dbdcc6bf965 ("dmaengine: ti-dma-crossbar: Add support for crossbar on AM33xx/AM43xx")
Signed-off-by: Peter Ujfalusi 
Signed-off-by: Vinod Koul 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

dmaengine: Fix array index out of bounds warning in __get_unmap_pool()

2017-12-20T09:07:21+00:00

[ Upstream commit 23f963e91fd81f44f6b316b1c24db563354c6be8 ]

This fixes the following warning when building with clang and
CONFIG_DMA_ENGINE_RAID=n :

drivers/dma/dmaengine.c:1102:11: error: array index 2 is past the end of the array (which contains 1 element) [-Werror,-Warray-bounds]
                return &unmap_pool[2];
                        ^          ~
drivers/dma/dmaengine.c:1083:1: note: array 'unmap_pool' declared here
static struct dmaengine_unmap_pool unmap_pool[] = {
^
drivers/dma/dmaengine.c:1104:11: error: array index 3 is past the end of the array (which contains 1 element) [-Werror,-Warray-bounds]
                return &unmap_pool[3];
                        ^          ~
drivers/dma/dmaengine.c:1083:1: note: array 'unmap_pool' declared here
static struct dmaengine_unmap_pool unmap_pool[] = {

Signed-off-by: Matthias Kaehlcke 
Reviewed-by: Dan Williams 
Signed-off-by: Vinod Koul 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

dmaengine: dmatest: move callback wait queue to thread context

2017-12-20T09:07:17+00:00

commit 6f6a23a213be51728502b88741ba6a10cda2441d upstream.

Commit adfa543e7314 ("dmatest: don't use set_freezable_with_signal()")
introduced a bug (that is in fact documented by the patch commit text)
that leaves behind a dangling pointer. Since the done_wait structure is
allocated on the stack, future invocations to the DMATEST can produce
undesirable results (e.g., corrupted spinlocks).

Commit a9df21e34b42 ("dmaengine: dmatest: warn user when dma test times
out") attempted to WARN the user that the stack was likely corrupted but
did not fix the actual issue.

This patch fixes the issue by pushing the wait queue and callback
structs into the the thread structure. If a failure occurs due to time,
dmaengine_terminate_all will force the callback to safely call
wake_up_all() without possibility of using a freed pointer.

Bug: https://bugzilla.kernel.org/show_bug.cgi?id=197605
Fixes: adfa543e7314 ("dmatest: don't use set_freezable_with_signal()")
Reviewed-by: Sinan Kaya 
Suggested-by: Shunyong Yang 
Signed-off-by: Adam Wallis 
Signed-off-by: Vinod Koul 
Signed-off-by: Greg Kroah-Hartman

dmaengine: pl330: fix double lock

2017-12-09T21:01:53+00:00

[ Upstream commit 91539eb1fda2d530d3b268eef542c5414e54bf1a ]

The static bug finder EBA (http://www.iagoabal.eu/eba/) reported the
following double-lock bug:

    Double lock:
    1. spin_lock_irqsave(pch->lock, flags) at pl330_free_chan_resources:2236;
    2. call to function `pl330_release_channel' immediately after;
    3. call to function `dma_pl330_rqcb' in line 1753;
    4. spin_lock_irqsave(pch->lock, flags) at dma_pl330_rqcb:1505.

I have fixed it as suggested by Marek Szyprowski.

First, I have replaced `pch->lock' with `pl330->lock' in functions
`pl330_alloc_chan_resources' and `pl330_free_chan_resources'. This avoids
the double-lock by acquiring a different lock than `dma_pl330_rqcb'.

NOTE that, as a result, `pl330_free_chan_resources' executes
`list_splice_tail_init' on `pch->work_list' under lock `pl330->lock',
whereas in the rest of the code `pch->work_list' is protected by
`pch->lock'. I don't know if this may cause race conditions. Similarly
`pch->cyclic' is written by `pl330_alloc_chan_resources' under
`pl330->lock' but read by `pl330_tx_submit' under `pch->lock'.

Second, I have removed locking from `pl330_request_channel' and
`pl330_release_channel' functions. Function `pl330_request_channel' is
only called from `pl330_alloc_chan_resources', so the lock is already
held. Function `pl330_release_channel' is called from
`pl330_free_chan_resources', which already holds the lock, and from
`pl330_del'. Function `pl330_del' is called in an error path of
`pl330_probe' and at the end of `pl330_remove', but I assume that there
cannot be concurrent accesses to the protected data at those points.

Signed-off-by: Iago Abal 
Reviewed-by: Marek Szyprowski 
Signed-off-by: Vinod Koul 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

dmaengine: stm32-dma: Fix null pointer dereference in stm32_dma_tx_status

2017-12-09T21:01:50+00:00

[ Upstream commit 57b5a32135c813f2ab669039fb4ec16b30cb3305 ]

chan->desc is always set to NULL when a DMA transfer is complete.
As a DMA transfer could be complete during the call of stm32_dma_tx_status,
we need to be sure that chan->desc is not NULL before using this variable
to avoid a null pointer deference issue.

Signed-off-by: M'boumba Cedric Madianga 
Reviewed-by: Ludovic BARRE 
Signed-off-by: Vinod Koul 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman 
Acked-by: Pierre-Yves MORDRET

dmaengine: stm32-dma: Set correct args number for DMA request from DT

2017-12-09T21:01:50+00:00

[ Upstream commit 7e96304d99477de1f70db42035071e56439da817 ]

This patch sets the right number of arguments to be used for DMA clients
which request channels from DT.

Signed-off-by: M'boumba Cedric Madianga 
Reviewed-by: Ludovic BARRE 
Signed-off-by: Vinod Koul 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

dmaengine: zx: set DMA_CYCLIC cap_mask bit

2017-11-30T08:39:11+00:00

[ Upstream commit fc318d64f3d91e15babac00e08354b1beb650b57 ]

The zx_dma driver supports cyclic transfer mode.  Let's set DMA_CYCLIC
cap_mask bit to make that clear, and avoid unnecessary failure when
clients request channel via dma_request_chan_by_mask() with DMA_CYCLIC
bit set in mask.

Signed-off-by: Shawn Guo 
Reviewed-by: Jun Nie 
Signed-off-by: Vinod Koul 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

dmaengine: dmatest: warn user when dma test times out

2017-11-24T07:33:42+00:00

commit a9df21e34b422f79d9a9fa5c3eff8c2a53491be6 upstream.

Commit adfa543e7314 ("dmatest: don't use set_freezable_with_signal()")
introduced a bug (that is in fact documented by the patch commit text)
that leaves behind a dangling pointer. Since the done_wait structure is
allocated on the stack, future invocations to the DMATEST can produce
undesirable results (e.g., corrupted spinlocks). Ideally, this would be
cleaned up in the thread handler, but at the very least, the kernel
is left in a very precarious scenario that can lead to some long debug
sessions when the crash comes later.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=197605
Signed-off-by: Adam Wallis 
Signed-off-by: Vinod Koul 
Signed-off-by: Greg Kroah-Hartman

dmaengine: ti-dma-crossbar: Fix possible race condition with dma_inuse

2017-10-18T07:35:38+00:00

commit 2ccb4837c938357233a0b8818e3ca3e58242c952 upstream.

When looking for unused xbar_out lane we should also protect the set_bit()
call with the same mutex to protect against concurrent threads picking the
same ID.

Fixes: ec9bfa1e1a796 ("dmaengine: ti-dma-crossbar: dra7: Use bitops instead of idr")
Signed-off-by: Peter Ujfalusi 
Signed-off-by: Vinod Koul 
Signed-off-by: Greg Kroah-Hartman

dmaengine: edma: Align the memcpy acnt array size with the transfer

2017-10-18T07:35:38+00:00

commit 87a2f622cc6446c7d09ac655b7b9b04886f16a4c upstream.

Memory to Memory transfers does not have any special alignment needs
regarding to acnt array size, but if one of the areas are in memory mapped
regions (like PCIe memory), we need to make sure that the acnt array size
is aligned with the mem copy parameters.

Before "dmaengine: edma: Optimize memcpy operation" change the memcpy was set
up in a different way: acnt == number of bytes in a word based on
__ffs((src | dest | len), bcnt and ccnt for looping the necessary number of
words to comlete the trasnfer.

Instead of reverting the commit we can fix it to make sure that the ACNT size
is aligned to the traswnfer.

Fixes: df6694f80365a (dmaengine: edma: Optimize memcpy operation)
Signed-off-by: Peter Ujfalusi 
Signed-off-by: Vinod Koul 
Signed-off-by: Greg Kroah-Hartman