Regression: serial: imx: overrun errors on debug UART

[Francesco Dolcini]

On Sat, Mar 25, 2023 at 10:00:24PM +0300, Sergey Organov wrote:
> In correctly working RT system this doesn't typically happen, as CPUs
> are way faster than typical UART speeds, and are able to handle the
> loads easily, provided UART has decent FIFO. It's disabling IRQs for
> prolonged times that makes shit happen.

The first time we were looking into this issue was before 7a637784d517
and with a PREEMPT-RT patched kernel (if I remember correctly it was a
v5.4).

The system was not loaded at all and it was pretty surprising the
behavior, because of the reasons you just wrote here.

Francesco