[PATCH 0/2] serial: qcom_geni: Quiesce UART transfers during panic and shutdown

Active UART DMA transfers can persist beyond VM shutdown or panic
scenarios, allowing the DMA engine to continue accessing IOVAs that have
already been invalidated during memory teardown. On VM-based platforms,
this can result in SMMU context faults and leave the GENI Serial Engine
in an undefined state. In panic scenarios, pending transfers may also
interfere with reliable panic console output.

This series addresses these issues by ensuring ongoing UART TX/RX
activity is stopped during both shutdown and panic flows.

Patch 1 adds a shutdown callback to quiesce the hardware during reboot
or VM shutdown, bringing the UART hardware to an idle state before reset
and preventing SMMU faults caused by DMA accesses after VM teardown.

Patch 2 adds a panic notifier to stop TX/RX activity during kernel
panic, preventing further DMA transactions and ensuring panic console
handling is not impacted by stuck transfers.

Signed-off-by: Praveen Talari <[email protected]>
---
Praveen Talari (2):
      serial: qcom_geni: Add shutdown callback to quiesce hardware on reboot
      serial: qcom_geni: Add panic notifier to stop UART on panic

 drivers/tty/serial/qcom_geni_serial.c | 36 +++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)
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base-commit: cc2b5f627e8ccbae1188ef2d8be3e451d7f933a5
change-id: 20260715-add_shutdown_and_panic_notifier_serial-2666cc2ac30f

Best regards,
--  
Praveen Talari <[email protected]>