misc: rp1-pio: release DMA channel outside pio->lock - #7519
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Fail transfers if they haven't first been configured. Signed-off-by: Phil Elwell <phil@raspberrypi.com>
rp1_pio_sm_dma_free() ends in dma_release_channel(), which sleeps while removing the sysfs links. Running it under pio->lock in SM_CONFIG_XFER triggers "BUG: scheduling while atomic" and hangs the machine when a client keeps reconfiguring a transfer. The claim bit stays set for this client across the unlock, so the channel remains reserved against other clients while it is released. Fixes: 0b7a604 ("misc: Add RP1 PIO driver") Link: raspberrypi#7512 Signed-off-by: Nicolai Buchwitz <nb@tipi-net.de>
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kernel: overlays: Add ramoops-pi5 See: raspberrypi/linux#7518 kernel: input: goodix: Include I2C details in names for the devices See: raspberrypi/linux#7506 kernel: misc: rp1-pio: release DMA channel outside pio->lock See: raspberrypi/linux#7519 kernel: ASoC: hifiberry-studio: add AES CS Mode control (channel status format) See: raspberrypi/linux#7527 kernel: pinctrl: rp1: Make IRQ usage set a pin to an input See: raspberrypi/linux#7526 kernel: drm/vc4: Support frame packed stereo modes See: raspberrypi/linux#7524
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kernel: overlays: Add ramoops-pi5 See: raspberrypi/linux#7518 kernel: input: goodix: Include I2C details in names for the devices See: raspberrypi/linux#7506 kernel: misc: rp1-pio: release DMA channel outside pio->lock See: raspberrypi/linux#7519 kernel: ASoC: hifiberry-studio: add AES CS Mode control (channel status format) See: raspberrypi/linux#7527 kernel: pinctrl: rp1: Make IRQ usage set a pin to an input See: raspberrypi/linux#7526 kernel: drm/vc4: Support frame packed stereo modes See: raspberrypi/linux#7524
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rp1_pio_sm_dma_free() ends in dma_release_channel(), which sleeps while
removing the sysfs links. Running it under pio->lock in SM_CONFIG_XFER
triggers "BUG: scheduling while atomic" and hangs the machine when a
client keeps reconfiguring a transfer.
The claim bit stays set for this client across the unlock, so the
channel remains reserved against other clients while it is released.