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Date: Sat, 7 Apr 2018 09:14:08 -0700
From: bob prohaska <fbsd@www.zefox.net>
To: Julian Elischer <julian@freebsd.org>
Cc: freebsd-current <freebsd-current@freebsd.org>,
 bob prohaska <fbsd@www.zefox.net>
Subject: Re: zfsloader: messy output on Dell iDrac serial console
Message-ID: <20180407161408.GA88547@www.zefox.net>
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On Sat, Apr 07, 2018 at 12:21:47PM +0800, Julian Elischer wrote:
> running on *some* Dell servers the serial console looks messed up at 
> the time of the FreeBSD menu.
> it looks like it's dropping (or adding? but that's less likely) 
> characters.
> 
>  ??|?? 5. [K]ernel: kernel (1 of 2)???????????????????? |?? .- .?????????????????????????????????????? -.
>  ??|?? 6. Configure Boot [O]ptions...???????????????? |2?? --| y/???????????? -.???????????? 

Scrambled console output has shown up on a Pi3 under what might be called
overload conditions, things like make -j8 buildworld and running of stress2's
default test suite. It doesn't seem to be a serial issue in that case.

Hard to believe you're seeing something related, but my $.02 anyway.

bob prohaska