Commit Graph

3271 Commits

Author SHA1 Message Date
Sven Van Asbroeck
9b8a4a188a dmaengine: imx-sdma: fix use-after-free on probe error path
[ Upstream commit 2b8066c3de ]

If probe() fails anywhere beyond the point where
sdma_get_firmware() is called, then a kernel oops may occur.

Problematic sequence of events:
1. probe() calls sdma_get_firmware(), which schedules the
   firmware callback to run when firmware becomes available,
   using the sdma instance structure as the context
2. probe() encounters an error, which deallocates the
   sdma instance structure
3. firmware becomes available, firmware callback is
   called with deallocated sdma instance structure
4. use after free - kernel oops !

Solution: only attempt to load firmware when we're certain
that probe() will succeed. This guarantees that the firmware
callback's context will remain valid.

Note that the remove() path is unaffected by this issue: the
firmware loader will increment the driver module's use count,
ensuring that the module cannot be unloaded while the
firmware callback is pending or running.

Signed-off-by: Sven Van Asbroeck <TheSven73@gmail.com>
Reviewed-by: Robin Gong <yibin.gong@nxp.com>
[vkoul: fixed braces for if condition]
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-08-04 09:33:14 +02:00
Robin Gong
6e8aa99a2e dmaengine: imx-sdma: remove BD_INTR for channel0
commit 3f93a4f297 upstream.

It is possible for an irq triggered by channel0 to be received later
after clks are disabled once firmware loaded during sdma probe. If
that happens then clearing them by writing to SDMA_H_INTR won't work
and the kernel will hang processing infinite interrupts. Actually,
don't need interrupt triggered on channel0 since it's pollling
SDMA_H_STATSTOP to know channel0 done rather than interrupt in
current code, just clear BD_INTR to disable channel0 interrupt to
avoid the above case.
This issue was brought by commit 1d069bfa3c ("dmaengine: imx-sdma:
ack channel 0 IRQ in the interrupt handler") which didn't take care
the above case.

Fixes: 1d069bfa3c ("dmaengine: imx-sdma: ack channel 0 IRQ in the interrupt handler")
Cc: stable@vger.kernel.org #5.0+
Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Reported-by: Sven Van Asbroeck <thesven73@gmail.com>
Tested-by: Sven Van Asbroeck <thesven73@gmail.com>
Reviewed-by: Michael Olbrich <m.olbrich@pengutronix.de>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-10 09:55:47 +02:00
Andy Shevchenko
e09a5cb80b dmaengine: idma64: Use actual device for DMA transfers
[ Upstream commit 5ba846b1ee ]

Intel IOMMU, when enabled, tries to find the domain of the device,
assuming it's a PCI one, during DMA operations, such as mapping or
unmapping. Since we are splitting the actual PCI device to couple of
children via MFD framework (see drivers/mfd/intel-lpss.c for details),
the DMA device appears to be a platform one, and thus not an actual one
that performs DMA. In a such situation IOMMU can't find or allocate
a proper domain for its operations. As a result, all DMA operations are
failed.

In order to fix this, supply parent of the platform device
to the DMA engine framework and fix filter functions accordingly.

We may rely on the fact that parent is a real PCI device, because no
other configuration is present in the wild.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [for tty parts]
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-06-22 08:17:17 +02:00
Sameer Pujar
e7df1de060 dmaengine: tegra210-adma: use devm_clk_*() helpers
[ Upstream commit f6ed6491d5 ]

adma driver is using pm_clk_*() interface for managing clock resources.
With this it is observed that clocks remain ON always. This happens on
Tegra devices which use BPMP co-processor to manage clock resources,
where clocks are enabled during prepare phase. This is necessary because
clocks to BPMP are always blocking. When pm_clk_*() interface is used on
such Tegra devices, clock prepare count is not balanced till remove call
happens for the driver and hence clocks are seen ON always. Thus this
patch replaces pm_clk_*() with devm_clk_*() framework.

Suggested-by: Mohan Kumar D <mkumard@nvidia.com>
Reviewed-by: Jonathan Hunter <jonathanh@nvidia.com>
Signed-off-by: Sameer Pujar <spujar@nvidia.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31 06:48:30 -07:00
Nicolas Ferre
5c1c6e26d5 dmaengine: at_xdmac: remove BUG_ON macro in tasklet
[ Upstream commit e2c114c06d ]

Even if this case shouldn't happen when controller is properly programmed,
it's still better to avoid dumping a kernel Oops for this.
As the sequence may happen only for debugging purposes, log the error and
just finish the tasklet call.

Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31 06:48:18 -07:00
Sugar Zhang
ab53d05491 dmaengine: pl330: _stop: clear interrupt status
[ Upstream commit 2da254cc79 ]

This patch kill instructs the DMAC to immediately terminate
execution of a thread. and then clear the interrupt status,
at last, stop generating interrupts for DMA_SEV. to guarantee
the next dma start is clean. otherwise, one interrupt maybe leave
to next start and make some mistake.

we can reporduce the problem as follows:

DMASEV: modify the event-interrupt resource, and if the INTEN sets
function as interrupt, the DMAC will set irq<event_num> HIGH to
generate interrupt. write INTCLR to clear interrupt.

	DMA EXECUTING INSTRUCTS		DMA TERMINATE
		|				|
		|				|
	       ...			      _stop
		|				|
		|			spin_lock_irqsave
	     DMASEV				|
		|				|
		|			    mask INTEN
		|				|
		|			     DMAKILL
		|				|
		|			spin_unlock_irqrestore

in above case, a interrupt was left, and if we unmask INTEN, the DMAC
will set irq<event_num> HIGH to generate interrupt.

to fix this, do as follows:

	DMA EXECUTING INSTRUCTS		DMA TERMINATE
		|				|
		|				|
	       ...			      _stop
		|				|
		|			spin_lock_irqsave
	     DMASEV				|
		|				|
		|			     DMAKILL
		|				|
		|			   clear INTCLR
		|			    mask INTEN
		|				|
		|			spin_unlock_irqrestore

Signed-off-by: Sugar Zhang <sugar.zhang@rock-chips.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31 06:48:15 -07:00
Sameer Pujar
12ada5b2b8 dmaengine: tegra210-dma: free dma controller in remove()
[ Upstream commit f030e41950 ]

Following kernel panic is seen during DMA driver unload->load sequence
==========================================================================
Unable to handle kernel paging request at virtual address ffffff8001198880
Internal error: Oops: 86000007 [#1] PREEMPT SMP
CPU: 0 PID: 5907 Comm: HwBinder:4123_1 Tainted: G C 4.9.128-tegra-g065839f
Hardware name: galen (DT)
task: ffffffc3590d1a80 task.stack: ffffffc3d0678000
PC is at 0xffffff8001198880
LR is at of_dma_request_slave_channel+0xd8/0x1f8
pc : [<ffffff8001198880>] lr : [<ffffff8008746f30>] pstate: 60400045
sp : ffffffc3d067b710
x29: ffffffc3d067b710 x28: 000000000000002f
x27: ffffff800949e000 x26: ffffff800949e750
x25: ffffff800949e000 x24: ffffffbefe817d84
x23: ffffff8009f77cb0 x22: 0000000000000028
x21: ffffffc3ffda49c8 x20: 0000000000000029
x19: 0000000000000001 x18: ffffffffffffffff
x17: 0000000000000000 x16: ffffff80082b66a0
x15: ffffff8009e78250 x14: 000000000000000a
x13: 0000000000000038 x12: 0101010101010101
x11: 0000000000000030 x10: 0101010101010101
x9 : fffffffffffffffc x8 : 7f7f7f7f7f7f7f7f
x7 : 62ff726b6b64622c x6 : 0000000000008064
x5 : 6400000000000000 x4 : ffffffbefe817c44
x3 : ffffffc3ffda3e08 x2 : ffffff8001198880
x1 : ffffffc3d48323c0 x0 : ffffffc3d067b788

Process HwBinder:4123_1 (pid: 5907, stack limit = 0xffffffc3d0678028)
Call trace:
[<ffffff8001198880>] 0xffffff8001198880
[<ffffff80087459f8>] dma_request_chan+0x50/0x1f0
[<ffffff8008745bc0>] dma_request_slave_channel+0x28/0x40
[<ffffff8001552c44>] tegra_alt_pcm_open+0x114/0x170
[<ffffff8008d65fa4>] soc_pcm_open+0x10c/0x878
[<ffffff8008d18618>] snd_pcm_open_substream+0xc0/0x170
[<ffffff8008d1878c>] snd_pcm_open+0xc4/0x240
[<ffffff8008d189e0>] snd_pcm_playback_open+0x58/0x80
[<ffffff8008cfc6d4>] snd_open+0xb4/0x178
[<ffffff8008250628>] chrdev_open+0xb8/0x1d0
[<ffffff8008246fdc>] do_dentry_open+0x214/0x318
[<ffffff80082485d0>] vfs_open+0x58/0x88
[<ffffff800825bce0>] do_last+0x450/0xde0
[<ffffff800825c718>] path_openat+0xa8/0x368
[<ffffff800825dd84>] do_filp_open+0x8c/0x110
[<ffffff8008248a74>] do_sys_open+0x164/0x220
[<ffffff80082b66dc>] compat_SyS_openat+0x3c/0x50
[<ffffff8008083040>] el0_svc_naked+0x34/0x38
---[ end trace 67e6d544e65b5145 ]---
Kernel panic - not syncing: Fatal exception
==========================================================================

In device probe(), of_dma_controller_register() registers DMA controller.
But when driver is removed, this is not freed. During driver reload this
results in data abort and kernel panic. Add of_dma_controller_free() in
driver remove path to fix the issue.

Fixes: f46b195799 ("dmaengine: tegra-adma: Add support for Tegra210 ADMA")
Signed-off-by: Sameer Pujar <spujar@nvidia.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31 06:48:13 -07:00
Dirk Behme
2996669f72 dmaengine: sh: rcar-dmac: With cyclic DMA residue 0 is valid
commit 907bd68a2e upstream.

Having a cyclic DMA, a residue 0 is not an indication of a completed
DMA. In case of cyclic DMA make sure that dma_set_residue() is called
and with this a residue of 0 is forwarded correctly to the caller.

Fixes: 3544d28788 ("dmaengine: rcar-dmac: use result of updated get_residue in tx_status")
Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
Signed-off-by: Achim Dahlhoff <Achim.Dahlhoff@de.bosch.com>
Signed-off-by: Hiroyuki Yokoyama <hiroyuki.yokoyama.vx@renesas.com>
Signed-off-by: Yao Lihua <ylhuajnu@outlook.com>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: <stable@vger.kernel.org> # v4.8+
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-02 09:32:02 +02:00
Ben Dooks
5f99bd3d9f dmaengine: tegra: avoid overflow of byte tracking
[ Upstream commit e486df3930 ]

The dma_desc->bytes_transferred counter tracks the number of bytes
moved by the DMA channel. This is then used to calculate the information
passed back in the in the tegra_dma_tx_status callback, which is usually
fine.

When the DMA channel is configured as continous, then the bytes_transferred
counter will increase over time and eventually overflow to become negative
so the residue count will become invalid and the ALSA sound-dma code will
report invalid hardware pointer values to the application. This results in
some users becoming confused about the playout position and putting audio
data in the wrong place.

To fix this issue, always ensure the bytes_transferred field is modulo the
size of the request. We only do this for the case of the cyclic transfer
done ISR as anyone attempting to move 2GiB of DMA data in one transfer
is unlikely.

Note, we don't fix the issue that we should /never/ transfer a negative
number of bytes so we could make those fields unsigned.

Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-05 22:29:15 +02:00
Shunyong Yang
817d556e9b dmaengine: qcom_hidma: assign channel cookie correctly
[ Upstream commit 546c054755 ]

When dma_cookie_complete() is called in hidma_process_completed(),
dma_cookie_status() will return DMA_COMPLETE in hidma_tx_status(). Then,
hidma_txn_is_success() will be called to use channel cookie
mchan->last_success to do additional DMA status check. Current code
assigns mchan->last_success after dma_cookie_complete(). This causes
a race condition of dma_cookie_status() returns DMA_COMPLETE before
mchan->last_success is assigned correctly. The race will cause
hidma_tx_status() return DMA_ERROR but the transaction is actually a
success. Moreover, in async_tx case, it will cause a timeout panic
in async_tx_quiesce().

 Kernel panic - not syncing: async_tx_quiesce: DMA error waiting for
 transaction
 ...
 Call trace:
 [<ffff000008089994>] dump_backtrace+0x0/0x1f4
 [<ffff000008089bac>] show_stack+0x24/0x2c
 [<ffff00000891e198>] dump_stack+0x84/0xa8
 [<ffff0000080da544>] panic+0x12c/0x29c
 [<ffff0000045d0334>] async_tx_quiesce+0xa4/0xc8 [async_tx]
 [<ffff0000045d03c8>] async_trigger_callback+0x70/0x1c0 [async_tx]
 [<ffff0000048b7d74>] raid_run_ops+0x86c/0x1540 [raid456]
 [<ffff0000048bd084>] handle_stripe+0x5e8/0x1c7c [raid456]
 [<ffff0000048be9ec>] handle_active_stripes.isra.45+0x2d4/0x550 [raid456]
 [<ffff0000048beff4>] raid5d+0x38c/0x5d0 [raid456]
 [<ffff000008736538>] md_thread+0x108/0x168
 [<ffff0000080fb1cc>] kthread+0x10c/0x138
 [<ffff000008084d34>] ret_from_fork+0x10/0x18

Cc: Joey Zheng <yu.zheng@hxt-semitech.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
Signed-off-by: Shunyong Yang <shunyong.yang@hxt-semitech.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-05 22:29:14 +02:00
Anders Roxell
a0a8b92db7 dmaengine: imx-dma: fix warning comparison of distinct pointer types
[ Upstream commit 9227ab5643 ]

The warning got introduced by commit 930507c183 ("arm64: add basic
Kconfig symbols for i.MX8"). Since it got enabled for arm64. The warning
haven't been seen before since size_t was 'unsigned int' when built on
arm32.

../drivers/dma/imx-dma.c: In function ‘imxdma_sg_next’:
../include/linux/kernel.h:846:29: warning: comparison of distinct pointer types lacks a cast
   (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
                             ^~
../include/linux/kernel.h:860:4: note: in expansion of macro ‘__typecheck’
   (__typecheck(x, y) && __no_side_effects(x, y))
    ^~~~~~~~~~~
../include/linux/kernel.h:870:24: note: in expansion of macro ‘__safe_cmp’
  __builtin_choose_expr(__safe_cmp(x, y), \
                        ^~~~~~~~~~
../include/linux/kernel.h:879:19: note: in expansion of macro ‘__careful_cmp’
 #define min(x, y) __careful_cmp(x, y, <)
                   ^~~~~~~~~~~~~
../drivers/dma/imx-dma.c:288:8: note: in expansion of macro ‘min’
  now = min(d->len, sg_dma_len(sg));
        ^~~

Rework so that we use min_t and pass in the size_t that returns the
minimum of two values, using the specified type.

Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Acked-by: Olof Johansson <olof@lixom.net>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-05 22:29:14 +02:00
Andy Shevchenko
ad3039362b dmaengine: dmatest: Abort test in case of mapping error
[ Upstream commit 6454368a80 ]

In case of mapping error the DMA addresses are invalid and continuing
will screw system memory or potentially something else.

[  222.480310] dmatest: dma0chan7-copy0: summary 1 tests, 3 failures 6 iops 349 KB/s (0)
...
[  240.912725] check: Corrupted low memory at 00000000c7c75ac9 (2940 phys) = 5656000000000000
[  240.921998] check: Corrupted low memory at 000000005715a1cd (2948 phys) = 279f2aca5595ab2b
[  240.931280] check: Corrupted low memory at 000000002f4024c0 (2950 phys) = 5e5624f349e793cf
...

Abort any test if mapping failed.

Fixes: 4076e755db ("dmatest: convert to dmaengine_unmap_data")
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-13 14:05:00 -07:00
Codrin Ciubotariu
b498cfefc3 dmaengine: at_xdmac: Fix wrongfull report of a channel as in use
[ Upstream commit dc3f595b66 ]

atchan->status variable is used to store two different information:
 - pass channel interrupts status from interrupt handler to tasklet;
 - channel information like whether it is cyclic or paused;

This causes a bug when device_terminate_all() is called,
(AT_XDMAC_CHAN_IS_CYCLIC cleared on atchan->status) and then a late End
of Block interrupt arrives (AT_XDMAC_CIS_BIS), which sets bit 0 of
atchan->status. Bit 0 is also used for AT_XDMAC_CHAN_IS_CYCLIC, so when
a new descriptor for a cyclic transfer is created, the driver reports
the channel as in use:

if (test_and_set_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status)) {
	dev_err(chan2dev(chan), "channel currently used\n");
	return NULL;
}

This patch fixes the bug by adding a different struct member to keep
the interrupts status separated from the channel status bits.

Fixes: e1f7c9eee7 ("dmaengine: at_xdmac: creation of the atmel eXtended DMA Controller driver")
Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-13 14:05:00 -07:00
Leonid Iziumtsev
d9f82def81 dmaengine: imx-dma: fix wrong callback invoke
commit 341198eda7 upstream.

Once the "ld_queue" list is not empty, next descriptor will migrate
into "ld_active" list. The "desc" variable will be overwritten
during that transition. And later the dmaengine_desc_get_callback_invoke()
will use it as an argument. As result we invoke wrong callback.

That behaviour was in place since:
commit fcaaba6c71 ("dmaengine: imx-dma: fix callback path in tasklet").
But after commit 4cd13c21b2 ("softirq: Let ksoftirqd do its job")
things got worse, since possible delay between tasklet_schedule()
from DMA irq handler and actual tasklet function execution got bigger.
And that gave more time for new DMA request to be submitted and
to be put into "ld_queue" list.

It has been noticed that DMA issue is causing problems for "mxc-mmc"
driver. While stressing the system with heavy network traffic and
writing/reading to/from sd card simultaneously the timeout may happen:

10013000.sdhci: mxcmci_watchdog: read time out (status = 0x30004900)

That often lead to file system corruption.

Signed-off-by: Leonid Iziumtsev <leonid.iziumtsev@gmail.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-12 19:45:01 +01:00
Lukas Wunner
3c8307940e dmaengine: bcm2835: Fix abort of transactions
commit 9e528c799d upstream.

There are multiple issues with bcm2835_dma_abort() (which is called on
termination of a transaction):

* The algorithm to abort the transaction first pauses the channel by
  clearing the ACTIVE flag in the CS register, then waits for the PAUSED
  flag to clear.  Page 49 of the spec documents the latter as follows:

  "Indicates if the DMA is currently paused and not transferring data.
   This will occur if the active bit has been cleared [...]"
   https://www.raspberrypi.org/app/uploads/2012/02/BCM2835-ARM-Peripherals.pdf

  So the function is entering an infinite loop because it is waiting for
  PAUSED to clear which is always set due to the function having cleared
  the ACTIVE flag.  The only thing that's saving it from itself is the
  upper bound of 10000 loop iterations.

  The code comment says that the intention is to "wait for any current
  AXI transfer to complete", so the author probably wanted to check the
  WAITING_FOR_OUTSTANDING_WRITES flag instead.  Amend the function
  accordingly.

* The CS register is only read at the beginning of the function.  It
  needs to be read again after pausing the channel and before checking
  for outstanding writes, otherwise writes which were issued between
  the register read at the beginning of the function and pausing the
  channel may not be waited for.

* The function seeks to abort the transfer by writing 0 to the NEXTCONBK
  register and setting the ABORT and ACTIVE flags.  Thereby, the 0 in
  NEXTCONBK is sought to be loaded into the CONBLK_AD register.  However
  experimentation has shown this approach to not work:  The CONBLK_AD
  register remains the same as before and the CS register contains
  0x00000030 (PAUSED | DREQ_STOPS_DMA).  In other words, the control
  block is not aborted but merely paused and it will be resumed once the
  next DMA transaction is started.  That is absolutely not the desired
  behavior.

  A simpler approach is to set the channel's RESET flag instead.  This
  reliably zeroes the NEXTCONBK as well as the CS register.  It requires
  less code and only a single MMIO write.  This is also what popular
  user space DMA drivers do, e.g.:
  https://github.com/metachris/RPIO/blob/master/source/c_pwm/pwm.c

  Note that the spec is contradictory whether the NEXTCONBK register
  is writeable at all.  On the one hand, page 41 claims:

  "The value loaded into the NEXTCONBK register can be overwritten so
  that the linked list of Control Block data structures can be
  dynamically altered. However it is only safe to do this when the DMA
  is paused."

  On the other hand, page 40 specifies:

  "Only three registers in each channel's register set are directly
  writeable (CS, CONBLK_AD and DEBUG). The other registers (TI,
  SOURCE_AD, DEST_AD, TXFR_LEN, STRIDE & NEXTCONBK), are automatically
  loaded from a Control Block data structure held in external memory."

Fixes: 96286b5766 ("dmaengine: Add support for BCM2835")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v3.14+
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Florian Meier <florian.meier@koalo.de>
Cc: Clive Messer <clive.m.messer@gmail.com>
Cc: Matthias Reichl <hias@horus.com>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Florian Kauer <florian.kauer@koalo.de>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-12 19:45:00 +01:00
Lukas Wunner
277242cc2c dmaengine: bcm2835: Fix interrupt race on RT
commit f7da7782ab upstream.

If IRQ handlers are threaded (either because CONFIG_PREEMPT_RT_BASE is
enabled or "threadirqs" was passed on the command line) and if system
load is sufficiently high that wakeup latency of IRQ threads degrades,
SPI DMA transactions on the BCM2835 occasionally break like this:

ks8851 spi0.0: SPI transfer timed out
bcm2835-dma 3f007000.dma: DMA transfer could not be terminated
ks8851 spi0.0 eth2: ks8851_rdfifo: spi_sync() failed

The root cause is an assumption made by the DMA driver which is
documented in a code comment in bcm2835_dma_terminate_all():

/*
 * Stop DMA activity: we assume the callback will not be called
 * after bcm_dma_abort() returns (even if it does, it will see
 * c->desc is NULL and exit.)
 */

That assumption falls apart if the IRQ handler bcm2835_dma_callback() is
threaded: A client may terminate a descriptor and issue a new one
before the IRQ handler had a chance to run. In fact the IRQ handler may
miss an *arbitrary* number of descriptors. The result is the following
race condition:

1. A descriptor finishes, its interrupt is deferred to the IRQ thread.
2. A client calls dma_terminate_async() which sets channel->desc = NULL.
3. The client issues a new descriptor. Because channel->desc is NULL,
   bcm2835_dma_issue_pending() immediately starts the descriptor.
4. Finally the IRQ thread runs and writes BCM2835_DMA_INT to the CS
   register to acknowledge the interrupt. This clears the ACTIVE flag,
   so the newly issued descriptor is paused in the middle of the
   transaction. Because channel->desc is not NULL, the IRQ thread
   finalizes the descriptor and tries to start the next one.

I see two possible solutions: The first is to call synchronize_irq()
in bcm2835_dma_issue_pending() to wait until the IRQ thread has
finished before issuing a new descriptor. The downside of this approach
is unnecessary latency if clients desire rapidly terminating and
re-issuing descriptors and don't have any use for an IRQ callback.
(The SPI TX DMA channel is a case in point.)

A better alternative is to make the IRQ thread recognize that it has
missed descriptors and avoid finalizing the newly issued descriptor.
So first of all, set the ACTIVE flag when acknowledging the interrupt.
This keeps a newly issued descriptor running.

If the descriptor was finished, the channel remains idle despite the
ACTIVE flag being set. However the ACTIVE flag can then no longer be
used to check whether the channel is idle, so instead check whether
the register containing the current control block address is zero
and finalize the current descriptor only if so.

That way, there is no impact on latency and throughput if the client
doesn't care for the interrupt: Only minimal additional overhead is
introduced for non-cyclic descriptors as one further MMIO read is
necessary per interrupt to check for idleness of the channel. Cyclic
descriptors are sped up slightly by removing one MMIO write per
interrupt.

Fixes: 96286b5766 ("dmaengine: Add support for BCM2835")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v3.14+
Cc: Frank Pavlic <f.pavlic@kunbus.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Cc: Florian Meier <florian.meier@koalo.de>
Cc: Clive Messer <clive.m.messer@gmail.com>
Cc: Matthias Reichl <hias@horus.com>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Florian Kauer <florian.kauer@koalo.de>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-12 19:45:00 +01:00
Nathan Chancellor
6f76b5a8f7 dmaengine: xilinx_dma: Remove __aligned attribute on zynqmp_dma_desc_ll
[ Upstream commit aeaebcc17c ]

Clang warns:

drivers/dma/xilinx/zynqmp_dma.c:166:4: warning: attribute 'aligned' is
ignored, place it after "struct" to apply attribute to type declaration
[-Wignored-attributes]
}; __aligned(64)
   ^
./include/linux/compiler_types.h:200:38: note: expanded from macro
'__aligned'
                                               ^
1 warning generated.

As Nick pointed out in the previous version of this patch, the author
likely intended for this struct to be 8-byte (64-bit) aligned, not
64-byte, which is the default. Remove the hanging __aligned attribute.

Fixes: b0cc417c16 ("dmaengine: Add Xilinx zynqmp dma engine driver support")
Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-12 19:44:52 +01:00
Bin Liu
1f7170700f dmaengine: cppi41: delete channel from pending list when stop channel
commit 59861547ec upstream.

The driver defines three states for a cppi channel.
- idle: .chan_busy == 0 && not in .pending list
- pending: .chan_busy == 0 && in .pending list
- busy: .chan_busy == 1 && not in .pending list

There are cases in which the cppi channel could be in the pending state
when cppi41_dma_issue_pending() is called after cppi41_runtime_suspend()
is called.

cppi41_stop_chan() has a bug for these cases to set channels to idle state.
It only checks the .chan_busy flag, but not the .pending list, then later
when cppi41_runtime_resume() is called the channels in .pending list will
be transitioned to busy state.

Removing channels from the .pending list solves the problem.

Fixes: 975faaeb99 ("dma: cppi41: start tear down only if channel is busy")
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Bin Liu <b-liu@ti.com>
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-13 09:20:29 +01:00
Richard Genoud
07d8abace8 dmaengine: at_hdmac: fix module unloading
commit 77e75fda94 upstream.

of_dma_controller_free() was not called on module onloading.
This lead to a soft lockup:
watchdog: BUG: soft lockup - CPU#0 stuck for 23s!
Modules linked in: at_hdmac [last unloaded: at_hdmac]
when of_dma_request_slave_channel() tried to call ofdma->of_dma_xlate().

Cc: stable@vger.kernel.org
Fixes: bbe89c8e3d ("at_hdmac: move to generic DMA binding")
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-05 19:42:40 +01:00
Richard Genoud
0daa7fc2c5 dmaengine: at_hdmac: fix memory leak in at_dma_xlate()
commit 98f5f93225 upstream.

The leak was found when opening/closing a serial port a great number of
time, increasing kmalloc-32 in slabinfo.

Each time the port was opened, dma_request_slave_channel() was called.
Then, in at_dma_xlate(), atslave was allocated with devm_kzalloc() and
never freed. (Well, it was free at module unload, but that's not what we
want).
So, here, kzalloc is more suited for the job since it has to be freed in
atc_free_chan_resources().

Cc: stable@vger.kernel.org
Fixes: bbe89c8e3d ("at_hdmac: move to generic DMA binding")
Reported-by: Mario Forner <m.forner@be4energy.com>
Suggested-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-05 19:42:40 +01:00
Paul Cercueil
e0362b434c dmaengine: dma-jz4780: Return error if not probed from DT
[ Upstream commit 54f919a04c ]

The driver calls clk_get() with the clock name set to NULL, which means
that the driver could only work when probed from devicetree. From now
on, we explicitly require the driver to be probed from devicetree.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Tested-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-13 11:16:53 -08:00
Waiman Long
479cd3e8ad driver/dma/ioat: Call del_timer_sync() without holding prep_lock
[ Upstream commit cfb03be6c7 ]

The following lockdep splat was observed:

[ 1222.241750] ======================================================
[ 1222.271301] WARNING: possible circular locking dependency detected
[ 1222.301060] 4.16.0-10.el8+5.x86_64+debug #1 Not tainted
[ 1222.326659] ------------------------------------------------------
[ 1222.356565] systemd-shutdow/1 is trying to acquire lock:
[ 1222.382660]  ((&ioat_chan->timer)){+.-.}, at: [<00000000f71e1a28>] del_timer_sync+0x5/0xf0
[ 1222.422928]
[ 1222.422928] but task is already holding lock:
[ 1222.451743]  (&(&ioat_chan->prep_lock)->rlock){+.-.}, at: [<000000008ea98b12>] ioat_shutdown+0x86/0x100 [ioatdma]
   :
[ 1223.524987] Chain exists of:
[ 1223.524987]   (&ioat_chan->timer) --> &(&ioat_chan->cleanup_lock)->rlock --> &(&ioat_chan->prep_lock)->rlock
[ 1223.524987]
[ 1223.594082]  Possible unsafe locking scenario:
[ 1223.594082]
[ 1223.622630]        CPU0                    CPU1
[ 1223.645080]        ----                    ----
[ 1223.667404]   lock(&(&ioat_chan->prep_lock)->rlock);
[ 1223.691535]                                lock(&(&ioat_chan->cleanup_lock)->rlock);
[ 1223.728657]                                lock(&(&ioat_chan->prep_lock)->rlock);
[ 1223.765122]   lock((&ioat_chan->timer));
[ 1223.784095]
[ 1223.784095]  *** DEADLOCK ***
[ 1223.784095]
[ 1223.813492] 4 locks held by systemd-shutdow/1:
[ 1223.834677]  #0:  (reboot_mutex){+.+.}, at: [<0000000056d33456>] SYSC_reboot+0x10f/0x300
[ 1223.873310]  #1:  (&dev->mutex){....}, at: [<00000000258dfdd7>] device_shutdown+0x1c8/0x660
[ 1223.913604]  #2:  (&dev->mutex){....}, at: [<0000000068331147>] device_shutdown+0x1d6/0x660
[ 1223.954000]  #3:  (&(&ioat_chan->prep_lock)->rlock){+.-.}, at: [<000000008ea98b12>] ioat_shutdown+0x86/0x100 [ioatdma]

In the ioat_shutdown() function:

	spin_lock_bh(&ioat_chan->prep_lock);
	set_bit(IOAT_CHAN_DOWN, &ioat_chan->state);
	del_timer_sync(&ioat_chan->timer);
	spin_unlock_bh(&ioat_chan->prep_lock);

According to the synchronization rule for the del_timer_sync() function,
the caller must not hold locks which would prevent completion of the
timer's handler.

The timer structure has its own lock that manages its synchronization.
Setting the IOAT_CHAN_DOWN bit should prevent other CPUs from
trying to use that device anyway, there is probably no need to call
del_timer_sync() while holding the prep_lock. So the del_timer_sync()
call is now moved outside of the prep_lock critical section to prevent
the circular lock dependency.

Signed-off-by: Waiman Long <longman@redhat.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-13 11:16:53 -08:00
Hanna Hawa
0c8706ef50 dmaengine: mv_xor_v2: kill the tasklets upon exit
[ Upstream commit 8bbafed8dd ]

The mv_xor_v2 driver uses a tasklet, initialized during the probe()
routine. However, it forgets to cleanup the tasklet using
tasklet_kill() function during the remove() routine, which this patch
fixes. This prevents the tasklet from potentially running after the
module has been removed.

Fixes: 19a340b1a8 ("dmaengine: mv_xor_v2: new driver")

Signed-off-by: Hanna Hawa <hannah@marvell.com>
Reviewed-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-26 08:36:34 +02:00
John Keeping
ddf00feadd dmaengine: pl330: fix irq race with terminate_all
[ Upstream commit e49756544a ]

In pl330_update() when checking if a channel has been aborted, the
channel's lock is not taken, only the overall pl330_dmac lock.  But in
pl330_terminate_all() the aborted flag (req_running==-1) is set under
the channel lock and not the pl330_dmac lock.

With threaded interrupts, this leads to a potential race:

    pl330_terminate_all	        pl330_update
    -------------------         ------------
    lock channel
                                entry
    lock pl330
    _stop channel
    unlock pl330
                                lock pl330
                                check req_running != -1
    req_running = -1
                                _start channel

Signed-off-by: John Keeping <john@metanate.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-26 08:36:31 +02:00
Dan Carpenter
87aea47373 dmaengine: k3dma: Off by one in k3_of_dma_simple_xlate()
[ Upstream commit c4c2b7644c ]

The d->chans[] array has d->dma_requests elements so the > should be
>= here.

Fixes: 8e6152bc66 ("dmaengine: Add hisilicon k3 DMA engine driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-24 13:12:33 +02:00
Marek Szyprowski
8c5fd3d56f dmaengine: pl330: report BURST residue granularity
[ Upstream commit e3f329c600 ]

The reported residue is already calculated in BURST unit granularity, so
advertise this capability properly to other devices in the system.

Fixes: aee4d1fac8 ("dmaengine: pl330: improve pl330_tx_status() function")
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-24 13:12:33 +02:00
Srinivas Kandagatla
cecf8a6904 dmaengine: qcom: bam_dma: get num-channels and num-ees from dt
[ Upstream commit 48d163b1aa ]

When Linux is master of BAM, it can directly read registers to know number
of supported channels, however when its remotely controlled reading these
registers would trigger a crash if the BAM is not yet initialized or
powered up on the remote side.

This patch allows driver to read num-channels and num-ees from Device Tree
for remotely controlled BAM.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:50:48 +02:00
Yoshihiro Shimoda
431f979f76 dmaengine: rcar-dmac: Check the done lists in rcar_dmac_chan_get_residue()
[ Upstream commit 3e081628d5 ]

This patch fixes an issue that a race condition happens between a client
driver and the rcar-dmac driver:

- The rcar_dmac_isr_transfer_end() is called.
 - The done list appears, and desc.running is the next active list.
- rcar_dmac_chan_get_residue() is called by a client driver before
  rcar_dmac_isr_channel_thread() is called.
 - The rcar_dmac_chan_get_residue() will not find any descriptors.
 - And, the following WARNING happens:
	WARN(1, "No descriptor for cookie!");

The sh-sci driver with HSCIF (921,600bps) on R-Car H3 can cause this
situation.
So, this patch checks the done lists in rcar_dmac_chan_get_residue()
and returns zero if the done lists has the argument cookie.

Tested-by: Nguyen Viet Dung <dung.nguyen.aj@renesas.com>
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:50:48 +02:00
Qi Hou
83f6484ce7 dmaengine: pl330: fix a race condition in case of threaded irqs
[ Upstream commit a3ca831249 ]

When booting up with "threadirqs" in command line, all irq handlers of the DMA
controller pl330 will be threaded forcedly. These threads will race for the same
list, pl330->req_done.

Before the callback, the spinlock was released. And after it, the spinlock was
taken. This opened an race window where another threaded irq handler could steal
the spinlock and be permitted to delete entries of the list, pl330->req_done.

If the later deleted an entry that was still referred to by the former, there would
be a kernel panic when the former was scheduled and tried to get the next sibling
of the deleted entry.

The scenario could be depicted as below:

  Thread: T1  pl330->req_done  Thread: T2
      |             |              |
      |          -A-B-C-D-         |
    Locked          |              |
      |             |           Waiting
    Del A           |              |
      |          -B-C-D-           |
    Unlocked        |              |
      |             |           Locked
    Waiting         |              |
      |             |            Del B
      |             |              |
      |           -C-D-         Unlocked
    Waiting         |              |
      |
    Locked
      |
   get C via B
      \
       - Kernel panic

The kernel panic looked like as below:

Unable to handle kernel paging request at virtual address dead000000000108
pgd = ffffff8008c9e000
[dead000000000108] *pgd=000000027fffe003, *pud=000000027fffe003, *pmd=0000000000000000
Internal error: Oops: 96000044 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 85 Comm: irq/59-66330000 Not tainted 4.8.24-WR9.0.0.12_standard #2
Hardware name: Broadcom NS2 SVK (DT)
task: ffffffc1f5cc3c00 task.stack: ffffffc1f5ce0000
PC is at pl330_irq_handler+0x27c/0x390
LR is at pl330_irq_handler+0x2a8/0x390
pc : [<ffffff80084cb694>] lr : [<ffffff80084cb6c0>] pstate: 800001c5
sp : ffffffc1f5ce3d00
x29: ffffffc1f5ce3d00 x28: 0000000000000140
x27: ffffffc1f5c530b0 x26: dead000000000100
x25: dead000000000200 x24: 0000000000418958
x23: 0000000000000001 x22: ffffffc1f5ccd668
x21: ffffffc1f5ccd590 x20: ffffffc1f5ccd418
x19: dead000000000060 x18: 0000000000000001
x17: 0000000000000007 x16: 0000000000000001
x15: ffffffffffffffff x14: ffffffffffffffff
x13: ffffffffffffffff x12: 0000000000000000
x11: 0000000000000001 x10: 0000000000000840
x9 : ffffffc1f5ce0000 x8 : ffffffc1f5cc3338
x7 : ffffff8008ce2020 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001
x3 : dead000000000200 x2 : dead000000000100
x1 : 0000000000000140 x0 : ffffffc1f5ccd590

Process irq/59-66330000 (pid: 85, stack limit = 0xffffffc1f5ce0020)
Stack: (0xffffffc1f5ce3d00 to 0xffffffc1f5ce4000)
3d00: ffffffc1f5ce3d80 ffffff80080f09d0 ffffffc1f5ca0c00 ffffffc1f6f7c600
3d20: ffffffc1f5ce0000 ffffffc1f6f7c600 ffffffc1f5ca0c00 ffffff80080f0998
3d40: ffffffc1f5ce0000 ffffff80080f0000 0000000000000000 0000000000000000
3d60: ffffff8008ce202c ffffff8008ce2020 ffffffc1f5ccd668 ffffffc1f5c530b0
3d80: ffffffc1f5ce3db0 ffffff80080f0d70 ffffffc1f5ca0c40 0000000000000001
3da0: ffffffc1f5ce0000 ffffff80080f0cfc ffffffc1f5ce3e20 ffffff80080bf4f8
3dc0: ffffffc1f5ca0c80 ffffff8008bf3798 ffffff8008955528 ffffffc1f5ca0c00
3de0: ffffff80080f0c30 0000000000000000 0000000000000000 0000000000000000
3e00: 0000000000000000 0000000000000000 0000000000000000 ffffff80080f0b68
3e20: 0000000000000000 ffffff8008083690 ffffff80080bf420 ffffffc1f5ca0c80
3e40: 0000000000000000 0000000000000000 0000000000000000 ffffff80080cb648
3e60: ffffff8008b1c780 0000000000000000 0000000000000000 ffffffc1f5ca0c00
3e80: ffffffc100000000 ffffff8000000000 ffffffc1f5ce3e90 ffffffc1f5ce3e90
3ea0: 0000000000000000 ffffff8000000000 ffffffc1f5ce3eb0 ffffffc1f5ce3eb0
3ec0: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
3ee0: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
3f00: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
3f20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
3f40: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
3f60: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
3f80: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
3fa0: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
3fc0: 0000000000000000 0000000000000005 0000000000000000 0000000000000000
3fe0: 0000000000000000 0000000000000000 0000000275ce3ff0 0000000275ce3ff8
Call trace:
Exception stack(0xffffffc1f5ce3b30 to 0xffffffc1f5ce3c60)
3b20:                                   dead000000000060 0000008000000000
3b40: ffffffc1f5ce3d00 ffffff80084cb694 0000000000000008 0000000000000e88
3b60: ffffffc1f5ce3bb0 ffffff80080dac68 ffffffc1f5ce3b90 ffffff8008826fe4
3b80: 00000000000001c0 00000000000001c0 ffffffc1f5ce3bb0 ffffff800848dfcc
3ba0: 0000000000020000 ffffff8008b15ae4 ffffffc1f5ce3c00 ffffff800808f000
3bc0: 0000000000000010 ffffff80088377f0 ffffffc1f5ccd590 0000000000000140
3be0: dead000000000100 dead000000000200 0000000000000001 0000000000000000
3c00: 0000000000000000 ffffff8008ce2020 ffffffc1f5cc3338 ffffffc1f5ce0000
3c20: 0000000000000840 0000000000000001 0000000000000000 ffffffffffffffff
3c40: ffffffffffffffff ffffffffffffffff 0000000000000001 0000000000000007
[<ffffff80084cb694>] pl330_irq_handler+0x27c/0x390
[<ffffff80080f09d0>] irq_forced_thread_fn+0x38/0x88
[<ffffff80080f0d70>] irq_thread+0x140/0x200
[<ffffff80080bf4f8>] kthread+0xd8/0xf0
[<ffffff8008083690>] ret_from_fork+0x10/0x40
Code: f2a00838 f9405763 aa1c03e1 aa1503e0 (f9000443)
---[ end trace f50005726d31199c ]---
Kernel panic - not syncing: Fatal exception in interrupt
SMP: stopping secondary CPUs
SMP: failed to stop secondary CPUs 0-1
Kernel Offset: disabled
Memory Limit: none
---[ end Kernel panic - not syncing: Fatal exception in interrupt

To fix this, re-start with the list-head after dropping the lock then
re-takeing it.

Reviewed-by: Frank Mori Hess <fmh6jj@gmail.com>
Tested-by: Frank Mori Hess <fmh6jj@gmail.com>
Signed-off-by: Qi Hou <qi.hou@windriver.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:50:48 +02:00
Gregory CLEMENT
3bdcced419 dmaengine: mv_xor_v2: Fix clock resource by adding a register clock
[ Upstream commit 3cd2c313f1 ]

On the CP110 components which are present on the Armada 7K/8K SoC we need
to explicitly enable the clock for the registers. However it is not
needed for the AP8xx component, that's why this clock is optional.

With this patch both clock have now a name, but in order to be backward
compatible, the name of the first clock is not used. It allows to still
use this clock with a device tree using the old binding.

Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:50:36 +02:00
Yoshihiro Shimoda
12700760a0 dmaengine: rcar-dmac: fix max_chunk_size for R-Car Gen3
[ Upstream commit d716d9b702 ]

According to R-Car Gen3 Rev.0.80 manual, the DMATCR can be set to
16,777,215 as maximum. So, this patch fixes the max_chunk_size for
safety on all of SoCs. Otherwise, a system may hang if the DMATCR
is set to 0 on R-Car Gen3.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:50:32 +02:00
Maxime Jayat
5d151871b1 dmaengine: at_xdmac: fix rare residue corruption
commit c5637476bb upstream.

Despite the efforts made to correctly read the NDA and CUBC registers,
the order in which the registers are read could sometimes lead to an
inconsistent state.

Re-using the timeline from the comments, this following timing of
registers reads could lead to reading NDA with value "@desc2" and
CUBC with value "MAX desc1":

 INITD --------                    ------------
              |____________________|
       _______________________  _______________
 NDA       @desc2             \/   @desc3
       _______________________/\_______________
       __________  ___________  _______________
 CUBC       0    \/ MAX desc1 \/  MAX desc2
       __________/\___________/\_______________
        |  |          |  |
Events:(1)(2)        (3)(4)

(1) check_nda = @desc2
(2) initd = 1
(3) cur_ubc = MAX desc1
(4) cur_nda = @desc2

This is allowed by the condition ((check_nda == cur_nda) && initd),
despite cur_ubc and cur_nda being in the precise state we don't want.

This error leads to incorrect residue computation.

Fix it by inversing the order in which CUBC and INITD are read. This
makes sure that NDA and CUBC are always read together either _before_
INITD goes to 0 or _after_ it is back at 1.
The case where NDA is read before INITD is at 0 and CUBC is read after
INITD is back at 1 will be rejected by check_nda and cur_nda being
different.

Fixes: 53398f4888 ("dmaengine: at_xdmac: fix residue corruption")
Cc: stable@vger.kernel.org
Signed-off-by: Maxime Jayat <maxime.jayat@mobile-devices.fr>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-24 09:34:13 +02:00
Arvind Yadav
922841084a dmaengine: imx-sdma: Handle return value of clk_prepare_enable
[ Upstream commit fb9caf370f ]

clk_prepare_enable() can fail here and we must check its return value.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-13 19:48:12 +02:00
Vignesh R
559205f289 dmaengine: ti-dma-crossbar: Fix event mapping for TPCC_EVT_MUX_60_63
[ Upstream commit d087f15786 ]

Register layout of a typical TPCC_EVT_MUX_M_N register is such that the
lowest numbered event is at the lowest byte address and highest numbered
event at highest byte address. But TPCC_EVT_MUX_60_63 register layout is
different,  in that the lowest numbered event is at the highest address
and highest numbered event is at the lowest address. Therefore, modify
ti_am335x_xbar_write() to handle TPCC_EVT_MUX_60_63 register
accordingly.

Signed-off-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-24 11:00:26 +01:00
Kedareswara rao Appana
2d443c9ee9 dmaengine: zynqmp_dma: Fix race condition in the probe
[ Upstream commit 5ba080aada ]

Incase of interrupt property is not present,
Driver is trying to free an invalid irq,
This patch fixes it by adding a check before freeing the irq.

Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-24 11:00:24 +01:00
Jiada Wang
61ed2d27b8 dmaengine: imx-sdma: add 1ms delay to ensure SDMA channel is stopped
[ Upstream commit 7f3ff14b7e ]

sdma_disable_channel() cannot ensure dma is stopped to access
module's FIFOs. There is chance SDMA core is running and accessing
BD when disable of corresponding channel, this may cause sometimes
even after call of .sdma_disable_channel(), SDMA core still be
running and accessing module's FIFOs.

According to NXP R&D team a delay of one BD SDMA cost time (maximum
is 1ms) should be added after disable of the channel bit, to ensure
SDMA core has really been stopped after SDMA clients call
.device_terminate_all.

This patch introduces adds a new function sdma_disable_channel_with_delay()
which simply adds 1ms delay after call sdma_disable_channel(),
and set it as .device_terminate_all.

Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-22 09:17:43 +01:00
Andreas Platschek
051337a899 dmaengine: fsl-edma: disable clks on all error paths
[ Upstream commit 2610acf46b ]

Previously enabled clks are only disabled if clk_prepare_enable() fails.
However, there are other error paths were the previously enabled
clocks are not disabled.

To fix the problem, fsl_disable_clocks() now takes the number of clocks
that shall be disabled + unprepared. For existing calls were all clocks
were already successfully prepared + enabled, DMAMUX_NR is passed to
disable + unprepare all clocks.

In error paths were only some clocks were successfully prepared +
enabled the loop counter is passed, in order to disable + unprepare
all successfully prepared + enabled clocks.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Andreas Platschek <andreas.platschek@opentech.at>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-03 10:23:20 +01:00
Jun Nie
c5d98b6400 dmaengine: zx: fix build warning
commit 067fdeb2f3 upstream.

Fix build warning that related to PAGE_SIZE. The maximum DMA
length has nothing to do with PAGE_SIZE, just use a fix number
for the definition.

drivers/dma/zx_dma.c: In function 'zx_dma_prep_memcpy':
drivers/dma/zx_dma.c:523:8: warning: division by zero [-Wdiv-by-zero]
drivers/dma/zx_dma.c: In function 'zx_dma_prep_slave_sg':
drivers/dma/zx_dma.c:567:11: warning: division by zero [-Wdiv-by-zero]

Signed-off-by: Jun Nie <jun.nie@linaro.org>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:05:53 +01:00
Tobias Jordan
b3e6030616 dmaengine: jz4740: disable/unprepare clk if probe fails
[ Upstream commit eb9436966f ]

in error path of jz4740_dma_probe(), call clk_disable_unprepare() to clean
up.

Found by Linux Driver Verification project (linuxtesting.org).

Fixes: 25ce6c35fe MIPS: jz4740: Remove custom DMA API
Signed-off-by: Tobias Jordan <Tobias.Jordan@elektrobit.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:05:49 +01:00
Gustavo A. R. Silva
3250df9fa8 dmaengine: at_hdmac: fix potential NULL pointer dereference in atc_prep_dma_interleaved
[ Upstream commit 62a277d43d ]

_xt_ is being dereferenced before it is null checked, hence there is a
potential null pointer dereference.

Fix this by moving the pointer dereference after _xt_ has been null
checked.

This issue was detected with the help of Coccinelle.

Fixes: 4483320e24 ("dmaengine: Use Pointer xt after NULL check.")
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:05:48 +01:00
Christophe JAILLET
b3df69b4ab dmaengine: ioat: Fix error handling path
[ Upstream commit 5c9afbda91 ]

If the last test in 'ioat_dma_self_test()' fails, we must release all
the allocated resources and not just part of them.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:05:48 +01:00
Yang Shunyong
297c7cc4b5 dmaengine: dmatest: fix container_of member in dmatest_callback
commit 66b3bd2356 upstream.

The type of arg passed to dmatest_callback is struct dmatest_done.
It refers to test_done in struct dmatest_thread, not done_wait.

Fixes: 6f6a23a213 ("dmaengine: dmatest: move callback wait ...")
Signed-off-by: Yang Shunyong <shunyong.yang@hxt-semitech.com>
Acked-by: Adam Wallis <awallis@codeaurora.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-17 13:21:12 +01:00
Peter Ujfalusi
5a7192bc38 dmaengine: ti-dma-crossbar: Correct am335x/am43xx mux value type
[ Upstream commit 288e7560e4 ]

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: 42dbdcc6bf ("dmaengine: ti-dma-crossbar: Add support for crossbar on AM33xx/AM43xx")
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-20 10:07:27 +01:00
Matthias Kaehlcke
e30ccb5f1c dmaengine: Fix array index out of bounds warning in __get_unmap_pool()
[ Upstream commit 23f963e91f ]

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 <mka@chromium.org>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-20 10:07:21 +01:00
Adam Wallis
679dbeac0b dmaengine: dmatest: move callback wait queue to thread context
commit 6f6a23a213 upstream.

Commit adfa543e73 ("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 a9df21e34b ("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: adfa543e73 ("dmatest: don't use set_freezable_with_signal()")
Reviewed-by: Sinan Kaya <okaya@codeaurora.org>
Suggested-by: Shunyong Yang <shunyong.yang@hxt-semitech.com>
Signed-off-by: Adam Wallis <awallis@codeaurora.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-20 10:07:17 +01:00
Iago Abal
49c3164e6d dmaengine: pl330: fix double lock
[ Upstream commit 91539eb1fd ]

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 <mail@iagoabal.eu>
Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-09 22:01:53 +01:00
M'boumba Cedric Madianga
7468e767d8 dmaengine: stm32-dma: Fix null pointer dereference in stm32_dma_tx_status
[ Upstream commit 57b5a32135 ]

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 <cedric.madianga@gmail.com>
Reviewed-by: Ludovic BARRE <ludovic.barre@st.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com>
2017-12-09 22:01:50 +01:00
M'boumba Cedric Madianga
000e718063 dmaengine: stm32-dma: Set correct args number for DMA request from DT
[ Upstream commit 7e96304d99 ]

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 <cedric.madianga@gmail.com>
Reviewed-by: Ludovic BARRE <ludovic.barre@st.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-09 22:01:50 +01:00
Shawn Guo
e7918c60da dmaengine: zx: set DMA_CYCLIC cap_mask bit
[ Upstream commit fc318d64f3 ]

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 <shawn.guo@linaro.org>
Reviewed-by: Jun Nie <jun.nie@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-30 08:39:11 +00:00
Adam Wallis
2bd38ece78 dmaengine: dmatest: warn user when dma test times out
commit a9df21e34b upstream.

Commit adfa543e73 ("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 <awallis@codeaurora.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-24 08:33:42 +01:00