When we get a DMA channel and try to use it in multiple threads it
will cause oops and hanging the system.
% echo 64 > /sys/module/dmatest/parameters/threads_per_chan
% echo 10000 > /sys/module/dmatest/parameters/iterations
% echo 1 > /sys/module/dmatest/parameters/run
[ 89.480664] Unable to handle kernel NULL pointer dereference at virtual
address 00000000000000a0
[ 89.488725] Oops [#1]
[ 89.494708] CPU: 2 PID: 1008 Comm: dma0chan0-copy0 Not tainted
5.17.0-rc5
[ 89.509385] epc : vchan_find_desc+0x32/0x46
[ 89.513553] ra : sf_pdma_tx_status+0xca/0xd6
This happens because of data race. Each thread rewrite channels's
descriptor as soon as device_prep_dma_memcpy() is called. It leads to the
situation when the driver thinks that it uses right descriptor that
actually is freed or substituted for other one.
With current fixes a descriptor changes its value only when it has
been used. A new descriptor is acquired from vc->desc_issued queue that
is already filled with descriptors that are ready to be sent. Threads
have no direct access to DMA channel descriptor. Now it is just possible
to queue a descriptor for further processing.
Fixes: 6973886ad5 ("dmaengine: sf-pdma: add platform DMA support for HiFive Unleashed A00")
Signed-off-by: Viacheslav Mitrofanov <v.v.mitrofanov@yadro.com>
Link: https://lore.kernel.org/r/20220701082942.12835-1-v.v.mitrofanov@yadro.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
It currently assumes that there are always four channels, it would
cause the error if there is actually less than four channels. Change
that by getting number of channel from device tree.
For backwards-compatibility, it uses the default value (i.e. 4) when
there is no 'dma-channels' information in dts.
Signed-off-by: Zong Li <zong.li@sifive.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Link: https://lore.kernel.org/r/f08a95b6582a51712c5b2c3cb859136d07bfa8b9.1648461096.git.zong.li@sifive.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
New drivers/devices
- Support for QCOM SM8250 GPI DMA
- removal of shdma-of driver and binding
Updates:
- arm-pl08x yaml binding move
- altera-msgdma gained DT support
- removal of imx-sdma platform data support
- idxd and xilinx driver updates
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Merge tag 'dmaengine-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine
Pull dmaengine updates from Vinod Koul:
"This time around we have a smaller pull request than usual and this
includes code removal, so should be good!
New drivers/devices
- Support for QCOM SM8250 GPI DMA
- removal of shdma-of driver and binding
Updates:
- arm-pl08x yaml binding move
- altera-msgdma gained DT support
- removal of imx-sdma platform data support
- idxd and xilinx driver updates"
* tag 'dmaengine-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine: (22 commits)
dmaengine: imx-sdma: Remove platform data header
dmaengine: xilinx: dpdma: Fix spacing around addr[i-1]
dmaengine: xilinx: dpdma: Use kernel type u32 over uint32_t
dmaengine: altera-msgdma: add OF support
MAINTAINERS: add entry for Altera mSGDMA
dt-bindings: dma: add schema for altera-msgdma
dmaengine: xilinx: dpdma: fix kernel-doc
dmaengine: sf-pdma: apply proper spinlock flags in sf_pdma_prep_dma_memcpy()
dmaengine: sh: Remove unused shdma-of driver
dt-bindings: dmaengine: Remove SHDMA Device Tree bindings
dmaengine: qcom: gpi: Add SM8250 compatible
dt-bindings: dmaengine: qcom: gpi: add compatible for sm8250
dmaengine: sun4i: Use list_move_tail instead of list_del/list_add_tail
dmaengine: ti: omap-dma: Skip pointless cpu_pm context restore on errors
dmaengine: hsu: Account transferred bytes
dmaengine: Move kdoc description of struct dma_chan_percpu closer to it
dmaengine: xilinx: dpdma: Print debug message when losing vsync race
dmaengine: xilinx: dpdma: Print channel number in kernel log messages
dt-bindings: dma: convert arm-pl08x to yaml
dmaengine: idxd: remove devm allocation for idxd->int_handles
...
The second parameter of spinlock_irq[save/restore] function is flags,
which is the last input parameter of sf_pdma_prep_dma_memcpy().
So declare local variable 'iflags' to be used as the second parameter of
spinlock_irq[save/restore] function.
Signed-off-by: Austin Kim <austin.kim@lge.com>
Link: https://lore.kernel.org/r/20210611065336.GA1121@raspberrypi
Signed-off-by: Vinod Koul <vkoul@kernel.org>
When CONFIG_HAS_IOMEM is not set/enabled, certain iomap() family
functions [including ioremap(), devm_ioremap(), etc.] are not
available.
Drivers that use these functions should depend on HAS_IOMEM so that
they do not cause build errors.
Mends this build error:
s390-linux-ld: drivers/dma/sf-pdma/sf-pdma.o: in function `sf_pdma_probe':
sf-pdma.c:(.text+0x1668): undefined reference to `devm_ioremap_resource'
Fixes: 6973886ad5 ("dmaengine: sf-pdma: add platform DMA support for HiFive Unleashed A00")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: kernel test robot <lkp@intel.com>
Cc: Green Wan <green.wan@sifive.com>
Cc: Vinod Koul <vkoul@kernel.org>
Cc: dmaengine@vger.kernel.org
Link: https://lore.kernel.org/r/20210522021313.16405-4-rdunlap@infradead.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The driver can match only via the DT table so the table should be always
used and the of_match_ptr does not have any sense (this also allows ACPI
matching via PRP0001, even though it is not relevant here). This fixes
compile warning (!CONFIG_OF on x86_64):
drivers/dma/sf-pdma/sf-pdma.c:576:34: warning:
‘sf_pdma_dt_ids’ defined but not used [-Wunused-const-variable=]
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20201120162303.482126-4-krzk@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Running in hardIRQ, disabling IRQ is redundant since hardIRQ has disabled
IRQ. This patch removes the irqsave and irqstore to save some instruction
cycles.
Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Cc: Green Wan <green.wan@sifive.com>
Link: https://lore.kernel.org/r/20201027215252.25820-4-song.bao.hua@hisilicon.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
In preparation for unconditionally passing the
struct tasklet_struct pointer to all tasklet
callbacks, switch to using the new tasklet_setup()
and from_tasklet() to pass the tasklet pointer explicitly.
Signed-off-by: Romain Perier <romain.perier@gmail.com>
Signed-off-by: Allen Pais <apais@linux.microsoft.com>
Link: https://lore.kernel.org/r/20201006050458.221329-1-allen.lkml@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
'desc' variable is now defined but not used in sf_pdma_donebh_tasklet(),
causing this warning:
drivers/dma/sf-pdma/sf-pdma.c: In function 'sf_pdma_donebh_tasklet':
drivers/dma/sf-pdma/sf-pdma.c:287:23: warning: unused variable 'desc' [-Wunused-variable]
Remove this unused variable
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Link: https://lore.kernel.org/r/20200914055302.22962-1-vkoul@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Because a callback is called twice when DMA transfer complete
the second callback may be possible to access a freed memory
if the first callback routines perform the dma_release_channel function.
So this patch serialized the callback functions
Signed-off-by: Brad Kim <brad.kim@semifive.com>
Tested-and-reviewed-by: Green Wan <green.wan@sifive.com>
Signed-off-by: Brad Kim <brad.kim@sifive.com>
Link: https://lore.kernel.org/r/20200903111726.3413-1-brad.kim@sifive.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The header file linux/uio.h includes crypto/hash.h which pulls in
most of the Crypto API. Since linux/uio.h is used throughout the
kernel this means that every tiny bit of change to the Crypto API
causes the entire kernel to get rebuilt.
This patch fixes this by moving it into lib/iov_iter.c instead
where it is actually used.
This patch also fixes the ifdef to use CRYPTO_HASH instead of just
CRYPTO which does not guarantee the existence of ahash.
Unfortunately a number of drivers were relying on linux/uio.h to
provide access to linux/slab.h. This patch adds inclusions of
linux/slab.h as detected by build failures.
Also skbuff.h was relying on this to provide a declaration for
ahash_request. This patch adds a forward declaration instead.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
There is no need to explicitly free memory that have been 'devm_kzalloc'ed.
Simplify the probe function accordingly.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Tested-by: Green Wan <green.wan@sifive.com>
Reviewed-by: Green Wan <green.wan@sifive.com>
Link: https://lore.kernel.org/r/20200501100824.126534-1-christophe.jaillet@wanadoo.fr
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Originally freeing descriptors was split into a locked and an unlocked
part. The locked part in vchan_get_all_descriptors() collected all
descriptors on a separate list_head. This was done to allow iterating
over that new list in vchan_dma_desc_free_list() without a lock held.
This became broken in 13bb26ae88 ("dmaengine: virt-dma: don't always
free descriptor upon completion"). With this commit
vchan_dma_desc_free_list() no longer exclusively operates on the
separate list, but starts to put descriptors which can be reused back on
&vc->desc_allocated. This list operation should have been locked, but
wasn't.
In the mean time drivers started to call vchan_dma_desc_free_list() with
their lock held so that we now have the situation that
vchan_dma_desc_free_list() is called locked from some drivers and
unlocked from others.
To clean this up we have to do two things:
1. Add missing locking in vchan_dma_desc_free_list()
2. Make sure drivers call vchan_dma_desc_free_list() unlocked
This needs to be done atomically, so in this patch the locking is added
and all drivers are fixed.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Tested-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: Green Wan <green.wan@sifive.com>
Tested-by: Green Wan <green.wan@sifive.com>
Link: https://lore.kernel.org/r/20191216105328.15198-3-s.hauer@pengutronix.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The place where the macro, SF_PDMA_REG_BASE(), is cause kernel-doc
using wrong function declaration. Move it to header file.
Signed-off-by: Green Wan <green.wan@sifive.com>
Link: https://lore.kernel.org/r/20191118143554.16129-2-green.wan@sifive.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
There are several comments starting from "/**" but not for function
comment purpose. It causes kernel-doc parsing wrong string. Replace
"/**" with "/*" to fix them.
Signed-off-by: Green Wan <green.wan@sifive.com>
Link: https://lore.kernel.org/r/20191118143554.16129-1-green.wan@sifive.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
