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Date:   Sun, 26 Mar 2023 20:21:24 +0200
From:   Francesco Dolcini <francesco@dolcini.it>
To:     Sergey Organov <sorganov@gmail.com>
Cc:     Stefan Wahren <stefan.wahren@i2se.com>,
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Subject: Re: Regression: serial: imx: overrun errors on debug UART
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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