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2020-03-11dmaengine: coh901318: Fix a double lock bug in dma_tc_handle()Dan Carpenter
commit 36d5d22090d13fd3a7a8c9663a711cbe6970aac8 upstream. The caller is already holding the lock so this will deadlock. Fixes: 0b58828c923e ("DMAENGINE: COH 901 318 remove irq counting") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Link: https://lore.kernel.org/r/20200217144050.3i4ymbytogod4ijn@kili.mountain Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-11dmaengine: tegra-apb: Prevent race conditions of tasklet vs free listDmitry Osipenko
commit c33ee1301c393a241d6424e36eff1071811b1064 upstream. The interrupt handler puts a half-completed DMA descriptor on a free list and then schedules tasklet to process bottom half of the descriptor that executes client's callback, this creates possibility to pick up the busy descriptor from the free list. Thus, let's disallow descriptor's re-use until it is fully processed. Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Acked-by: Jon Hunter <jonathanh@nvidia.com> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20200209163356.6439-3-digetx@gmail.com Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-11dmaengine: tegra-apb: Fix use-after-freeDmitry Osipenko
commit 94788af4ed039476ff3527b0e6a12c1dc42cb022 upstream. I was doing some experiments with I2C and noticed that Tegra APB DMA driver crashes sometime after I2C DMA transfer termination. The crash happens because tegra_dma_terminate_all() bails out immediately if pending list is empty, and thus, it doesn't release the half-completed descriptors which are getting re-used before ISR tasklet kicks-in. tegra-i2c 7000c400.i2c: DMA transfer timeout elants_i2c 0-0010: elants_i2c_irq: failed to read data: -110 ------------[ cut here ]------------ WARNING: CPU: 0 PID: 142 at lib/list_debug.c:45 __list_del_entry_valid+0x45/0xac list_del corruption, ddbaac44->next is LIST_POISON1 (00000100) Modules linked in: CPU: 0 PID: 142 Comm: kworker/0:2 Not tainted 5.5.0-rc2-next-20191220-00175-gc3605715758d-dirty #538 Hardware name: NVIDIA Tegra SoC (Flattened Device Tree) Workqueue: events_freezable_power_ thermal_zone_device_check [<c010e5c5>] (unwind_backtrace) from [<c010a1c5>] (show_stack+0x11/0x14) [<c010a1c5>] (show_stack) from [<c0973925>] (dump_stack+0x85/0x94) [<c0973925>] (dump_stack) from [<c011f529>] (__warn+0xc1/0xc4) [<c011f529>] (__warn) from [<c011f7e9>] (warn_slowpath_fmt+0x61/0x78) [<c011f7e9>] (warn_slowpath_fmt) from [<c042497d>] (__list_del_entry_valid+0x45/0xac) [<c042497d>] (__list_del_entry_valid) from [<c047a87f>] (tegra_dma_tasklet+0x5b/0x154) [<c047a87f>] (tegra_dma_tasklet) from [<c0124799>] (tasklet_action_common.constprop.0+0x41/0x7c) [<c0124799>] (tasklet_action_common.constprop.0) from [<c01022ab>] (__do_softirq+0xd3/0x2a8) [<c01022ab>] (__do_softirq) from [<c0124683>] (irq_exit+0x7b/0x98) [<c0124683>] (irq_exit) from [<c0168c19>] (__handle_domain_irq+0x45/0x80) [<c0168c19>] (__handle_domain_irq) from [<c043e429>] (gic_handle_irq+0x45/0x7c) [<c043e429>] (gic_handle_irq) from [<c0101aa5>] (__irq_svc+0x65/0x94) Exception stack(0xde2ebb90 to 0xde2ebbd8) Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Acked-by: Jon Hunter <jonathanh@nvidia.com> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20200209163356.6439-2-digetx@gmail.com Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-29dmaengine: ti: edma: fix missed failure handlingChuhong Yuan
[ Upstream commit 340049d453682a9fe8d91fe794dd091730f4bb25 ] When devm_kcalloc fails, it forgets to call edma_free_slot. Replace direct return with failure handler to fix it. Fixes: 1be5336bc7ba ("dmaengine: edma: New device tree binding") Signed-off-by: Chuhong Yuan <hslester96@gmail.com> Link: https://lore.kernel.org/r/20191118073802.28424-1-hslester96@gmail.com Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-29dmaengine: imx-sdma: fix size check for sdma script_numberRobin Gong
[ Upstream commit bd73dfabdda280fc5f05bdec79b6721b4b2f035f ] Illegal memory will be touch if SDMA_SCRIPT_ADDRS_ARRAY_SIZE_V3 (41) exceed the size of structure sdma_script_start_addrs(40), thus cause memory corrupt such as slob block header so that kernel trap into while() loop forever in slob_free(). Please refer to below code piece in imx-sdma.c: for (i = 0; i < sdma->script_number; i++) if (addr_arr[i] > 0) saddr_arr[i] = addr_arr[i]; /* memory corrupt here */ That issue was brought by commit a572460be9cf ("dmaengine: imx-sdma: Add support for version 3 firmware") because SDMA_SCRIPT_ADDRS_ARRAY_SIZE_V3 (38->41 3 scripts added) not align with script number added in sdma_script_start_addrs(2 scripts). Fixes: a572460be9cf ("dmaengine: imx-sdma: Add support for version 3 firmware") Cc: stable@vger.kernel Link: https://www.spinics.net/lists/arm-kernel/msg754895.html Signed-off-by: Robin Gong <yibin.gong@nxp.com> Reported-by: Jurgen Lambrecht <J.Lambrecht@TELEVIC.com> Link: https://lore.kernel.org/r/1569347584-3478-1-git-send-email-yibin.gong@nxp.com [vkoul: update the patch title] Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-29dmaengine: dw: platform: Switch to acpi_dma_controller_register()Andy Shevchenko
[ Upstream commit e7b8514e4d68bec21fc6385fa0a66797ddc34ac9 ] There is a possibility to have registered ACPI DMA controller while it has been gone already. To avoid the potential crash, move to non-managed acpi_dma_controller_register(). Fixes: 42c91ee71d6d ("dw_dmac: add ACPI support") Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20190820131546.75744-8-andriy.shevchenko@linux.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-29dmaengine: hsu: Revert "set HSU_CH_MTSR to memory width"Andy Shevchenko
[ Upstream commit c24a5c735f87d0549060de31367c095e8810b895 ] The commit 080edf75d337 ("dmaengine: hsu: set HSU_CH_MTSR to memory width") has been mistakenly submitted. The further investigations show that the original code does better job since the memory side transfer size has never been configured by DMA users. As per latest revision of documentation: "Channel minimum transfer size (CHnMTSR)... For IOSF UART, maximum value that can be programmed is 64 and minimum value that can be programmed is 1." This reverts commit 080edf75d337d35faa6fc3df99342b10d2848d16. Fixes: 080edf75d337 ("dmaengine: hsu: set HSU_CH_MTSR to memory width") 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>
2020-01-29dmaengine: tegra210-adma: Fix crash during probeJon Hunter
[ Upstream commit b53611fb1ce9b1786bd18205473e0c1d6bfa8934 ] Commit f33e7bb3eb92 ("dmaengine: tegra210-adma: restore channel status") added support to save and restore the DMA channel registers when runtime suspending the ADMA. This change is causing the kernel to crash when probing the ADMA, if the device is probed deferred when looking up the channel interrupts. The crash occurs because not all of the channel base addresses have been setup at this point and in the clean-up path of the probe, pm_runtime_suspend() is called invoking its callback which expects all the channel base addresses to be initialised. Although this could be fixed by simply checking for a NULL address, on further review of the driver it seems more appropriate that we only call pm_runtime_get_sync() after all the channel interrupts and base addresses have been configured. Therefore, fix this crash by moving the calls to pm_runtime_enable(), pm_runtime_get_sync() and tegra_adma_init() after the DMA channels have been initialised. Fixes: f33e7bb3eb92 ("dmaengine: tegra210-adma: restore channel status") Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-29dmaengine: tegra210-adma: restore channel statusSameer Pujar
[ Upstream commit f33e7bb3eb922618612a90f0a828c790e8880773 ] Status of ADMA channel registers is not saved and restored during system suspend. During active playback if system enters suspend, this results in wrong state of channel registers during system resume and playback fails to resume properly. Fix this by saving following channel registers in runtime suspend and restore during runtime resume. * ADMA_CH_LOWER_SRC_ADDR * ADMA_CH_LOWER_TRG_ADDR * ADMA_CH_FIFO_CTRL * ADMA_CH_CONFIG * ADMA_CH_CTRL * ADMA_CH_CMD * ADMA_CH_TC Runtime PM calls will be inovked during system resume path if a playback or capture needs to be resumed. Hence above changes work fine for system suspend case. 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>
2020-01-29dmaengine: axi-dmac: Don't check the number of frames for alignmentAlexandru Ardelean
[ Upstream commit 648865a79d8ee3d1aa64aab5eb2a9d12eeed14f9 ] In 2D transfers (for the AXI DMAC), the number of frames (numf) represents Y_LENGTH, and the length of a frame is X_LENGTH. 2D transfers are useful for video transfers where screen resolutions ( X * Y ) are typically aligned for X, but not for Y. There is no requirement for Y_LENGTH to be aligned to the bus-width (or anything), and this is also true for AXI DMAC. Checking the Y_LENGTH for alignment causes false errors when initiating DMA transfers. This change fixes this by checking only that the Y_LENGTH is non-zero. Fixes: 0e3b67b348b8 ("dmaengine: Add support for the Analog Devices AXI-DMAC DMA controller") Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-29dmaengine: mv_xor: Use correct device for DMA APIRobin Murphy
[ Upstream commit 3e5daee5ecf314da33a890fabaa2404244cd2a36 ] Using dma_dev->dev for mappings before it's assigned with the correct device is unlikely to work as expected, and with future dma-direct changes, passing a NULL device may end up crashing entirely. I don't know enough about this hardware or the mv_xor_prep_dma_interrupt() operation to implement the appropriate error-handling logic that would have revealed those dma_map_single() calls failing on arm64 for as long as the driver has been enabled there, but moving the assignment earlier will at least make the current code operate as intended. Fixes: 22843545b200 ("dma: mv_xor: Add support for DMA_INTERRUPT") Reported-by: John David Anglin <dave.anglin@bell.net> Tested-by: John David Anglin <dave.anglin@bell.net> Signed-off-by: Robin Murphy <robin.murphy@arm.com> Acked-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Tested-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-23ioat: ioat_alloc_ring() failure handling.Alexander.Barabash@dell.com
[ Upstream commit b0b5ce1010ffc50015eaec72b0028aaae3f526bb ] If dma_alloc_coherent() returns NULL in ioat_alloc_ring(), ring allocation must not proceed. Until now, if the first call to dma_alloc_coherent() in ioat_alloc_ring() returned NULL, the processing could proceed, failing with NULL-pointer dereferencing further down the line. Signed-off-by: Alexander Barabash <alexander.barabash@dell.com> Acked-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/75e9c0e84c3345d693c606c64f8b9ab5@x13pwhopdag1307.AMER.DELL.COM Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-12-21dmaengine: coh901318: Remove unused variableVinod Koul
commit 35faaf0df42d285b40f8a6310afbe096720f7758 upstream. Commit 627469e4445b ("dmaengine: coh901318: Fix a double-lock bug") left flags variable unused, so remove it to fix the warning. drivers/dma/coh901318.c: In function 'coh901318_config': drivers/dma/coh901318.c:1805:16: warning: unused variable 'flags' [-Wunused-variable] unsigned long flags; ^~~~~ Fixes: 627469e4445b ("dmaengine: coh901318: Fix a double-lock bug") Reported-By: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-21dmaengine: coh901318: Fix a double-lock bugJia-Ju Bai
[ Upstream commit 627469e4445b9b12e0229b3bdf8564d5ce384dd7 ] The function coh901318_alloc_chan_resources() calls spin_lock_irqsave() before calling coh901318_config(). But coh901318_config() calls spin_lock_irqsave() again in its definition, which may cause a double-lock bug. Because coh901318_config() is only called by coh901318_alloc_chan_resources(), the bug fix is to remove the calls to spin-lock and -unlock functions in coh901318_config(). Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.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>
2019-11-25dmaengine: ioat: fix prototype of ioat_enumerate_channelsRami Rosen
[ Upstream commit f4d34aa8c887a8a2d23ef546da0efa10e3f77241 ] Signed-off-by: Rami Rosen <ramirose@gmail.com> Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-25dmaengine: timb_dma: Use proper enum in td_prep_slave_sgNathan Chancellor
[ Upstream commit 5e621f5d538985f010035c6f3e28c22829d36db1 ] Clang warns when implicitly converting from one enumerated type to another. Avoid this by using the equivalent value from the expected type. drivers/dma/timb_dma.c:548:27: warning: implicit conversion from enumeration type 'enum dma_transfer_direction' to different enumeration type 'enum dma_data_direction' [-Wenum-conversion] td_desc->desc_list_len, DMA_MEM_TO_DEV); ^~~~~~~~~~~~~~ 1 warning generated. Reported-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>
2019-11-25dmaengine: dma-jz4780: Further residue status fixDaniel Silsby
[ Upstream commit 83ef4fb7556b6a673f755da670cbacab7e2c7f1b ] Func jz4780_dma_desc_residue() expects the index to the next hw descriptor as its last parameter. Caller func jz4780_dma_tx_status(), however, applied modulus before passing it. When the current hw descriptor was last in the list, the index passed became zero. The resulting excess of reported residue especially caused problems with cyclic DMA transfer clients, i.e. ALSA AIC audio output, which rely on this for determining current DMA location within buffer. Combined with the recent and related residue-reporting fixes, spurious ALSA audio underruns on jz4770 hardware are now fixed. Signed-off-by: Daniel Silsby <dansilsby@gmail.com> 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>
2019-11-25dmaengine: dma-jz4780: Don't depend on MACH_JZ4780Paul Cercueil
[ Upstream commit c558ecd21c852c97ff98dc6c61f715ba420ec251 ] If we make this driver depend on MACH_JZ4780, that means it can be enabled only if we're building a kernel specially crafted for a JZ4780-based board, while most GNU/Linux distributions will want one generic MIPS kernel that works on multiple boards. Signed-off-by: Paul Cercueil <paul@crapouillou.net> Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-12dmaengine: xilinx_dma: Fix control reg update in vdma_channel_set_configRadhey Shyam Pandey
[ Upstream commit 6c6de1ddb1be3840f2ed5cc9d009a622720940c9 ] In vdma_channel_set_config clear the delay, frame count and master mask before updating their new values. It avoids programming incorrect state when input parameters are different from default. Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com> Acked-by: Appana Durga Kedareswara rao <appana.durga.rao@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Link: https://lore.kernel.org/r/1569495060-18117-3-git-send-email-radhey.shyam.pandey@xilinx.com Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-10dmaengine: qcom: bam_dma: Fix resource leakJeffrey Hugo
commit 7667819385457b4aeb5fac94f67f52ab52cc10d5 upstream. bam_dma_terminate_all() will leak resources if any of the transactions are committed to the hardware (present in the desc fifo), and not complete. Since bam_dma_terminate_all() does not cause the hardware to be updated, the hardware will still operate on any previously committed transactions. This can cause memory corruption if the memory for the transaction has been reassigned, and will cause a sync issue between the BAM and its client(s). Fix this by properly updating the hardware in bam_dma_terminate_all(). Fixes: e7c0fe2a5c84 ("dmaengine: add Qualcomm BAM dma driver") Signed-off-by: Jeffrey Hugo <jeffrey.l.hugo@gmail.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20191017152606.34120-1-jeffrey.l.hugo@gmail.com Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-06dmaengine: cppi41: Fix cppi41_dma_prep_slave_sg() when idleTony Lindgren
commit bacdcb6675e170bb2e8d3824da220e10274f42a7 upstream. Yegor Yefremov <yegorslists@googlemail.com> reported that musb and ftdi uart can fail for the first open of the uart unless connected using a hub. This is because the first dma call done by musb_ep_program() must wait if cppi41 is PM runtime suspended. Otherwise musb_ep_program() continues with other non-dma packets before the DMA transfer is started causing at least ftdi uarts to fail to receive data. Let's fix the issue by waking up cppi41 with PM runtime calls added to cppi41_dma_prep_slave_sg() and return NULL if still idled. This way we have musb_ep_program() continue with PIO until cppi41 is awake. Fixes: fdea2d09b997 ("dmaengine: cppi41: Add basic PM runtime support") Reported-by: Yegor Yefremov <yegorslists@googlemail.com> Signed-off-by: Tony Lindgren <tony@atomide.com> Cc: stable@vger.kernel.org # v4.9+ Link: https://lore.kernel.org/r/20191023153138.23442-1-tony@atomide.com Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-05dmaengine: ti: edma: Do not reset reserved paRAM slotsPeter Ujfalusi
[ Upstream commit c5dbe60664b3660f5ac5854e21273ea2e7ff698f ] Skip resetting paRAM slots marked as reserved as they might be used by other cores. Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Link: https://lore.kernel.org/r/20190823125618.8133-2-peter.ujfalusi@ti.com Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-10-05dmaengine: iop-adma: use correct printk format stringsArnd Bergmann
[ Upstream commit 00c9755524fbaa28117be774d7c92fddb5ca02f3 ] When compile-testing on other architectures, we get lots of warnings about incorrect format strings, like: drivers/dma/iop-adma.c: In function 'iop_adma_alloc_slots': drivers/dma/iop-adma.c:307:6: warning: format '%x' expects argument of type 'unsigned int', but argument 6 has type 'dma_addr_t {aka long long unsigned int}' [-Wformat=] drivers/dma/iop-adma.c: In function 'iop_adma_prep_dma_memcpy': >> drivers/dma/iop-adma.c:518:40: warning: format '%u' expects argument of type 'unsigned int', but argument 5 has type 'size_t {aka long unsigned int}' [-Wformat=] Use %zu for printing size_t as required, and cast the dma_addr_t arguments to 'u64' for printing with %llx. Ideally this should use the %pad format string, but that requires an lvalue argument that doesn't work here. Link: https://lore.kernel.org/r/20190809163334.489360-3-arnd@arndb.de Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-10-05dmaengine: bcm2835: Print error in case setting DMA mask failsStefan Wahren
[ Upstream commit 72503b25ee363827aafffc3e8d872e6a92a7e422 ] During enabling of the RPi 4, we found out that the driver doesn't provide a helpful error message in case setting DMA mask fails. So add one. Signed-off-by: Stefan Wahren <wahrenst@gmx.net> Link: https://lore.kernel.org/r/1563297318-4900-1-git-send-email-wahrenst@gmx.net Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-09-21dmaengine: ti: omap-dma: Add cleanup in omap_dma_probe()Wenwen Wang
[ Upstream commit 962411b05a6d3342aa649e39cda1704c1fc042c6 ] If devm_request_irq() fails to disable all interrupts, no cleanup is performed before retuning the error. To fix this issue, invoke omap_dma_free() to do the cleanup. Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu> Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Link: https://lore.kernel.org/r/1565938570-7528-1-git-send-email-wenwen@cs.uga.edu Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-09-21dmaengine: ti: dma-crossbar: Fix a memory leak bugWenwen Wang
[ Upstream commit 2c231c0c1dec42192aca0f87f2dc68b8f0cbc7d2 ] In ti_dra7_xbar_probe(), 'rsv_events' is allocated through kcalloc(). Then of_property_read_u32_array() is invoked to search for the property. However, if this process fails, 'rsv_events' is not deallocated, leading to a memory leak bug. To fix this issue, free 'rsv_events' before returning the error. Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu> Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Link: https://lore.kernel.org/r/1565938136-7249-1-git-send-email-wenwen@cs.uga.edu Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-09-06dmaengine: ste_dma40: fix unneeded variable warningArnd Bergmann
[ Upstream commit 5d6fb560729a5d5554e23db8d00eb57cd0021083 ] clang-9 points out that there are two variables that depending on the configuration may only be used in an ARRAY_SIZE() expression but not referenced: drivers/dma/ste_dma40.c:145:12: error: variable 'd40_backup_regs' is not needed and will not be emitted [-Werror,-Wunneeded-internal-declaration] static u32 d40_backup_regs[] = { ^ drivers/dma/ste_dma40.c:214:12: error: variable 'd40_backup_regs_chan' is not needed and will not be emitted [-Werror,-Wunneeded-internal-declaration] static u32 d40_backup_regs_chan[] = { Mark these __maybe_unused to shut up the warning. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20190712091357.744515-1-arnd@arndb.de Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-08-06dmaengine: rcar-dmac: Reject zero-length slave DMA requestsGeert Uytterhoeven
[ Upstream commit 78efb76ab4dfb8f74f290ae743f34162cd627f19 ] While the .device_prep_slave_sg() callback rejects empty scatterlists, it still accepts single-entry scatterlists with a zero-length segment. These may happen if a driver calls dmaengine_prep_slave_single() with a zero len parameter. The corresponding DMA request will never complete, leading to messages like: rcar-dmac e7300000.dma-controller: Channel Address Error happen and DMA timeouts. Although requesting a zero-length DMA request is a driver bug, rejecting it early eases debugging. Note that the .device_prep_dma_memcpy() callback already rejects requests to copy zero bytes. Reported-by: Eugeniu Rosca <erosca@de.adit-jv.com> Analyzed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-08-04dmaengine: imx-sdma: fix use-after-free on probe error pathSven Van Asbroeck
[ 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>
2019-07-10dmaengine: imx-sdma: remove BD_INTR for channel0Robin Gong
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>
2019-06-22dmaengine: idma64: Use actual device for DMA transfersAndy Shevchenko
[ 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>
2019-05-31dmaengine: tegra210-adma: use devm_clk_*() helpersSameer Pujar
[ 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>
2019-05-31dmaengine: at_xdmac: remove BUG_ON macro in taskletNicolas Ferre
[ 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>
2019-05-31dmaengine: pl330: _stop: clear interrupt statusSugar Zhang
[ 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>
2019-05-31dmaengine: tegra210-dma: free dma controller in remove()Sameer Pujar
[ 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>
2019-05-02dmaengine: sh: rcar-dmac: With cyclic DMA residue 0 is validDirk Behme
commit 907bd68a2edc491849e2fdcfe52c4596627bca94 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: 3544d2878817 ("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>
2019-04-05dmaengine: tegra: avoid overflow of byte trackingBen Dooks
[ Upstream commit e486df39305864604b7e25f2a95d51039517ac57 ] 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>
2019-04-05dmaengine: qcom_hidma: assign channel cookie correctlyShunyong Yang
[ Upstream commit 546c0547555efca8ba8c120716c325435e29df1b ] 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>
2019-04-05dmaengine: imx-dma: fix warning comparison of distinct pointer typesAnders Roxell
[ Upstream commit 9227ab5643cb8350449502dd9e3168a873ab0e3b ] The warning got introduced by commit 930507c18304 ("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>
2019-03-13dmaengine: dmatest: Abort test in case of mapping errorAndy Shevchenko
[ Upstream commit 6454368a804c4955ccd116236037536f81e5b1f1 ] 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: 4076e755dbec ("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>
2019-03-13dmaengine: at_xdmac: Fix wrongfull report of a channel as in useCodrin Ciubotariu
[ Upstream commit dc3f595b6617ebc0307e0ce151e8f2f2b2489b95 ] 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: e1f7c9eee707 ("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>
2019-02-12dmaengine: imx-dma: fix wrong callback invokeLeonid Iziumtsev
commit 341198eda723c8c1cddbb006a89ad9e362502ea2 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 fcaaba6c7136 ("dmaengine: imx-dma: fix callback path in tasklet"). But after commit 4cd13c21b207 ("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>
2019-02-12dmaengine: bcm2835: Fix abort of transactionsLukas Wunner
commit 9e528c799d17a4ac37d788c81440b50377dd592d 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: 96286b576690 ("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>
2019-02-12dmaengine: bcm2835: Fix interrupt race on RTLukas Wunner
commit f7da7782aba92593f7b82f03d2409a1c5f4db91b 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: 96286b576690 ("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>
2019-02-12dmaengine: xilinx_dma: Remove __aligned attribute on zynqmp_dma_desc_llNathan Chancellor
[ Upstream commit aeaebcc17cdf37065d2693865eeb1ff1c7dc5bf3 ] 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: b0cc417c1637 ("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>
2018-12-13dmaengine: cppi41: delete channel from pending list when stop channelBin Liu
commit 59861547ec9a9736e7882f6fb0c096a720ff811a 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: 975faaeb9985 ("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>
2018-12-05dmaengine: at_hdmac: fix module unloadingRichard Genoud
commit 77e75fda94d2ebb86aa9d35fb1860f6395bf95de 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: bbe89c8e3d59 ("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>
2018-12-05dmaengine: at_hdmac: fix memory leak in at_dma_xlate()Richard Genoud
commit 98f5f932254b88ce828bc8e4d1642d14e5854caa 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: bbe89c8e3d59 ("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>
2018-11-13dmaengine: dma-jz4780: Return error if not probed from DTPaul Cercueil
[ Upstream commit 54f919a04cf221bc1601d1193682d4379dacacbd ] 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>
2018-11-13driver/dma/ioat: Call del_timer_sync() without holding prep_lockWaiman Long
[ Upstream commit cfb03be6c7e8a1591285849c361d67b09f5149f7 ] 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>
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