Re: Strange output on the console
From: Willy Tarreau
Date: Fri Feb 25 2022 - 01:37:40 EST
On Fri, Feb 25, 2022 at 06:12:35AM +0000, David Laight wrote:
> From: Steven Rostedt
> > Sent: 25 February 2022 04:01
> >
> > I've been noticing that my tests have been spitting out strange output on
> > the console. It would happen at boot up and then clear up. It looks like
> > something screwed up with the serial timing.
> >
> > Attached is a dmesg of one of my test runs as an example.
> >
> > I've noticed this on both 32 bit and 64 bit x86.
> >
> > I haven't had time to look deeper into this, but I figured I let you know
> > about it.
> >
> > And it always seems to happen right after:
> >
> > Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
> >
> > Maybe this is a serial issue and not a printk one? :-/
>
> Looks very much like the serial baud rate is being reset.
I don't think it's the baud rate, characters are still readable, it
looks more like a fifo being too short and causing lots of chars to
be dropped.
Willy