linux-stable.git/drivers/dma, branch v4.19.63 Linux kernel stable tree dmaengine: imx-sdma: fix use-after-free on probe error path 2019-07-26T07:13:56+00:00 Sven Van Asbroeck thesven73@gmail.com 2019-06-24T14:07:31+00:00 09593c25b975458025fd4cd15d5861cbaa33683d [ Upstream commit 2b8066c3deb9140fdf258417a51479b2aeaa7622 ] 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> 
[ Upstream commit 2b8066c3deb9140fdf258417a51479b2aeaa7622 ]

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>
dmaengine: imx-sdma: remove BD_INTR for channel0 2019-07-10T07:53:48+00:00 Robin Gong yibin.gong@nxp.com 2019-06-21T08:23:06+00:00 f37de75cb8ebfcb5aa048824e7dc706ecebad4ca commit 3f93a4f297961c12bb17aa16cb3a4d1291823cae 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 1d069bfa3c78 ("dmaengine: imx-sdma: ack channel 0 IRQ in the interrupt handler") which didn't take care the above case. Fixes: 1d069bfa3c78 ("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> 
commit 3f93a4f297961c12bb17aa16cb3a4d1291823cae 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 1d069bfa3c78 ("dmaengine: imx-sdma:
ack channel 0 IRQ in the interrupt handler") which didn't take care
the above case.

Fixes: 1d069bfa3c78 ("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>
dmaengine: qcom: bam_dma: Fix completed descriptors count 2019-07-10T07:53:48+00:00 Sricharan R sricharan@codeaurora.org 2019-06-28T12:09:46+00:00 018c968de710af1372d456ededc0a575ee038b92 commit f6034225442c4a87906d36e975fd9e99a8f95487 upstream. One space is left unused in circular FIFO to differentiate 'full' and 'empty' cases. So take that in to account while counting for the descriptors completed. Fixes the issue reported here, https://lkml.org/lkml/2019/6/18/669 Cc: stable@vger.kernel.org Reported-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Signed-off-by: Sricharan R <sricharan@codeaurora.org> Tested-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit f6034225442c4a87906d36e975fd9e99a8f95487 upstream.

One space is left unused in circular FIFO to differentiate
'full' and 'empty' cases. So take that in to account while
counting for the descriptors completed.

Fixes the issue reported here,
	https://lkml.org/lkml/2019/6/18/669

Cc: stable@vger.kernel.org
Reported-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Sricharan R <sricharan@codeaurora.org>
Tested-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
dmaengine: sprd: Fix block length overflow 2019-06-25T03:35:55+00:00 Eric Long eric.long@unisoc.com 2019-05-06T07:28:31+00:00 8f3793bfa3ea69af84d0a6a398ccc3d80e6860a8 [ Upstream commit 89d03b3c126d683f7b2cd5b07178493993d12448 ] The maximum value of block length is 0xffff, so if the configured transfer length is more than 0xffff, that will cause block length overflow to lead a configuration error. Thus we can set block length as the maximum burst length to avoid this issue, since the maximum burst length will not be a big value which is more than 0xffff. Signed-off-by: Eric Long <eric.long@unisoc.com> Signed-off-by: Baolin Wang <baolin.wang@linaro.org> Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 89d03b3c126d683f7b2cd5b07178493993d12448 ]

The maximum value of block length is 0xffff, so if the configured transfer length
is more than 0xffff, that will cause block length overflow to lead a configuration
error.

Thus we can set block length as the maximum burst length to avoid this issue, since
the maximum burst length will not be a big value which is more than 0xffff.

Signed-off-by: Eric Long <eric.long@unisoc.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
dmaengine: dw-axi-dmac: fix null dereference when pointer first is null 2019-06-25T03:35:55+00:00 Colin Ian King colin.king@canonical.com 2019-05-08T22:33:29+00:00 e478abd4ebf720121cbc5ab4bf14bd4b1cbe2f3a [ Upstream commit 0788611c9a0925c607de536b2449de5ed98ef8df ] In the unlikely event that axi_desc_get returns a null desc in the very first iteration of the while-loop the error exit path ends up calling axi_desc_put on a null pointer 'first' and this causes a null pointer dereference. Fix this by adding a null check on pointer 'first' before calling axi_desc_put. Addresses-Coverity: ("Explicit null dereference") Fixes: 1fe20f1b8454 ("dmaengine: Introduce DW AXI DMAC driver") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 0788611c9a0925c607de536b2449de5ed98ef8df ]

In the unlikely event that axi_desc_get returns a null desc in the
very first iteration of the while-loop the error exit path ends
up calling axi_desc_put on a null pointer 'first' and this causes
a null pointer dereference.  Fix this by adding a null check on
pointer 'first' before calling axi_desc_put.

Addresses-Coverity: ("Explicit null dereference")
Fixes: 1fe20f1b8454 ("dmaengine: Introduce DW AXI DMAC driver")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
dmaengine: idma64: Use actual device for DMA transfers 2019-06-15T09:54:10+00:00 Andy Shevchenko andriy.shevchenko@linux.intel.com 2019-03-18T15:39:30+00:00 9fdcb04e80e1d7a92c7eb23bc0ba1243bc30ddfd [ Upstream commit 5ba846b1ee0792f5a596b9b0b86d6e8cdebfab06 ] 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> 
[ Upstream commit 5ba846b1ee0792f5a596b9b0b86d6e8cdebfab06 ]

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>
dmaengine: tegra210-adma: use devm_clk_*() helpers 2019-05-31T13:46:31+00:00 Sameer Pujar spujar@nvidia.com 2019-03-13T11:32:36+00:00 6b2d1934d1f94cbfae1dceab38c7165492f9e715 [ Upstream commit f6ed6491d565c336a360471e0c29228e34f4380e ] 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> 
[ Upstream commit f6ed6491d565c336a360471e0c29228e34f4380e ]

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>
dmaengine: at_xdmac: remove BUG_ON macro in tasklet 2019-05-31T13:46:17+00:00 Nicolas Ferre nicolas.ferre@microchip.com 2019-04-03T10:23:57+00:00 83544b04a4065686eb9dc72a1001103c5ef19641 [ Upstream commit e2c114c06da2d9ffad5b16690abf008d6696f689 ] 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> 
[ Upstream commit e2c114c06da2d9ffad5b16690abf008d6696f689 ]

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>
dmaengine: pl330: _stop: clear interrupt status 2019-05-31T13:46:14+00:00 Sugar Zhang sugar.zhang@rock-chips.com 2019-04-03T11:06:22+00:00 1d057fefa0459a18c414308a2612f73f9eb8d72a [ Upstream commit 2da254cc7908105a60a6bb219d18e8dced03dcb9 ] 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> 
[ Upstream commit 2da254cc7908105a60a6bb219d18e8dced03dcb9 ]

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>
dmaengine: tegra210-dma: free dma controller in remove() 2019-05-31T13:46:08+00:00 Sameer Pujar spujar@nvidia.com 2019-05-02T12:55:16+00:00 19c2dd5025bbbf2f773e0213da87364191afa5db [ Upstream commit f030e419501cb95e961e9ed35c493b5d46a04eca ] 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: f46b195799b5 ("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> 
[ Upstream commit f030e419501cb95e961e9ed35c493b5d46a04eca ]

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: f46b195799b5 ("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>