On 08/07, Neeraj Upadhyay wrote:

Move the request_irq() call to the end of the msm_startup(),
so that we don't handle interrupts while msm_startup() is
running. This avoids potential races while initialization
is in progress. For example, consider below scenario
where rx handler reads the intermediate value of dma->chan,
set in msm_request_rx_dma(), and tries to do dma mapping,
which results in data abort.

uart_port_startup()
  msm_startup()
   request_irq()
   ...
   msm_request_rx_dma()
    ...
    dma->chan = dma_request_slave_channel_reason(dev, "rx");
    <UART RX IRQ>
     msm_uart_irq()
      msm_handle_rx_dm()
       msm_start_rx_dma()
        dma->desc = dma_map_single()
         <data abort>

Signed-off-by: Neeraj Upadhyay <redacted>
---

Or we can write the IMR register with 0 to mask all irqs before
requesting the irq handler be setup? We will unmask the
interrupts we care about anyway when we setup termios.

If not, this change is ok, but I would guess it doesn't fix
spurious irqs from happening while we keep configuring the
hardware.

Feel free to take my reviewed-by though.

Reviewed-by: Stephen Boyd <redacted>

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