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From:   David Laight <David.Laight@ACULAB.COM>
To:     'Steven Rostedt' <rostedt@goodmis.org>,
        LKML <linux-kernel@vger.kernel.org>
CC:     Petr Mladek <pmladek@suse.com>,
        Sergey Senozhatsky <senozhatsky@chromium.org>,
        John Ogness <john.ogness@linutronix.de>
Subject: RE: Strange output on the console
Thread-Topic: Strange output on the console
Thread-Index: AQHYKfxF0QTTTto/+k+8VsyEcwRQo6yjyM1g
Date:   Fri, 25 Feb 2022 06:12:35 +0000
Message-ID: <61226fc12ff9459d8daed8e346d6ab94@AcuMS.aculab.com>
References: <20220224230035.36547137@gandalf.local.home>
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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.

	David

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