linux/drivers/dma, branch v5.6

dmaengine: ti: k3-udma-glue: Fix an error handling path in 'k3_udma_glue_cfg_rx_flow()'

2020-03-23T06:18:34Z

All but one error handling paths in the 'k3_udma_glue_cfg_rx_flow()' function 'goto err' and call 'k3_udma_glue_release_rx_flow()'. This not correct because this function has a 'channel->flows_ready--;' at the end, but 'flows_ready' has not been incremented here, when we branch to the error handling path. In order to keep a correct value in 'flows_ready', un-roll 'k3_udma_glue_release_rx_flow()', simplify it, add some labels and branch at the correct places when an error is detected. Doing so, we also NULLify 'flow->udma_rflow' in a path that was lacking it. Fixes: d70241913413 ("dmaengine: ti: k3-udma: Add glue layer for non DMAengine user") Signed-off-by: Christophe JAILLET Acked-by: Peter Ujfalusi Link: https://lore.kernel.org/r/20200318191209.1267-1-christophe.jaillet@wanadoo.fr Signed-off-by: Vinod Koul

dmaengine: idxd: fix off by one on cdev dwq refcount

2020-03-23T06:02:06Z

The refcount check for dedicated workqueue (dwq) is off by one and allows more than 1 user to open the char device. Fix check so only a single user can open the device. Fixes: 42d279f9137a ("dmaengine: idxd: add char driver to expose submission portal to userland") Signed-off-by: Dave Jiang Link: https://lore.kernel.org/r/158403020187.10208.14117394394540710774.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul

dmaengine: move .device_release missing log warning to debug level

2020-03-11T09:12:59Z

Dmaengine core warns the drivers registering for missing .device_release implementation. The warning is accurate for dmaengine controllers which hotplug but not for rest. So reduce this to a debug log. Link: https://lore.kernel.org/r/20200306135018.2286959-1-vkoul@kernel.org Signed-off-by: Vinod Koul

dmaengine: imx-sdma: Fix the event id check to include RX event for UART6

2020-02-25T08:45:26Z

On i.MX6UL/ULL and i.MX6SX the DMA event id for the RX channel of UART6 is '0'. To fix the broken DMA support for UART6, we change the check for event_id0 to include '0' as a valid id. Fixes: 1ec1e82f2510 ("dmaengine: Add Freescale i.MX SDMA support") Signed-off-by: Frieder Schrempf Reviewed-by: Fabio Estevam Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200225082139.7646-1-frieder.schrempf@kontron.de Signed-off-by: Vinod Koul

dmaengine: tegra-apb: Prevent race conditions of tasklet vs free list

2020-02-25T06:27:09Z

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 Acked-by: Jon Hunter Cc: Link: https://lore.kernel.org/r/20200209163356.6439-3-digetx@gmail.com Signed-off-by: Vinod Koul

dmaengine: tegra-apb: Fix use-after-free

2020-02-25T06:27:09Z

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 [] (unwind_backtrace) from [] (show_stack+0x11/0x14) [] (show_stack) from [] (dump_stack+0x85/0x94) [] (dump_stack) from [] (__warn+0xc1/0xc4) [] (__warn) from [] (warn_slowpath_fmt+0x61/0x78) [] (warn_slowpath_fmt) from [] (__list_del_entry_valid+0x45/0xac) [] (__list_del_entry_valid) from [] (tegra_dma_tasklet+0x5b/0x154) [] (tegra_dma_tasklet) from [] (tasklet_action_common.constprop.0+0x41/0x7c) [] (tasklet_action_common.constprop.0) from [] (__do_softirq+0xd3/0x2a8) [] (__do_softirq) from [] (irq_exit+0x7b/0x98) [] (irq_exit) from [] (__handle_domain_irq+0x45/0x80) [] (__handle_domain_irq) from [] (gic_handle_irq+0x45/0x7c) [] (gic_handle_irq) from [] (__irq_svc+0x65/0x94) Exception stack(0xde2ebb90 to 0xde2ebbd8) Signed-off-by: Dmitry Osipenko Acked-by: Jon Hunter Cc: Link: https://lore.kernel.org/r/20200209163356.6439-2-digetx@gmail.com Signed-off-by: Vinod Koul

dmaengine: imx-sdma: fix context cache

2020-02-24T16:57:05Z

There is a DMA problem with the serial ports on i.MX6. When the following sequence is performed: 1) Open a port 2) Write some data 3) Close the port 4) Open a *different* port 5) Write some data 6) Close the port The second write sends nothing and the second close hangs. If the first close() is omitted it works. Adding logs to the the UART driver shows that the DMA is being setup but the callback is never invoked for the second write. This used to work in 4.19. Git bisect leads to: ad0d92d: "dmaengine: imx-sdma: refine to load context only once" This commit adds a "context_loaded" flag used to avoid unnecessary context setups. However the flag is only reset in sdma_channel_terminate_work(), which is only invoked in a worker triggered by sdma_terminate_all() IF there is an active descriptor. So, if no active descriptor remains when the channel is terminated, the flag is not reset and, when the channel is later reused the old context is used. Fix the problem by always resetting the flag in sdma_free_chan_resources(). Cc: stable@vger.kernel.org Signed-off-by: Martin Fuzzey Fixes: ad0d92d7ba6a ("dmaengine: imx-sdma: refine to load context only once") Reviewed-by: Fabio Estevam Link: https://lore.kernel.org/r/1580305274-27274-1-git-send-email-martin.fuzzey@flowbird.group Signed-off-by: Vinod Koul

dmaengine: idxd: wq size configuration needs to check global max size

2020-02-24T16:32:34Z

The current size_store() function for idxd sysfs does not check the total wq size. This allows configuration of all wqs with total wq size. Add check to make sure the wq sysfs attribute rejects storing of size over the total wq size. Fixes: c52ca478233c ("dmaengine: idxd: add configuration component of driver") Reported-by: Jerry Chen Signed-off-by: Dave Jiang Link: https://lore.kernel.org/r/158213309629.2509.3583411832507185041.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul

dmaengine: idxd: sysfs input of wq incorrect wq type should return error

2020-02-24T16:32:34Z

Currently when inputing an unrecognized wq type, we set the wq type to "none". It really should return error and not change the existing wq type that's in the kernel. Fixes: c52ca478233c ("dmaengine: idxd: add configuration component of driver") Reported-by: Yixin Zhang Signed-off-by: Dave Jiang Link: https://lore.kernel.org/r/158213304803.2290.13336343633425868211.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul

dmaengine: coh901318: Fix a double lock bug in dma_tc_handle()

2020-02-24T16:29:45Z

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 Link: https://lore.kernel.org/r/20200217144050.3i4ymbytogod4ijn@kili.mountain Signed-off-by: Vinod Koul