Installer of 20210225 snapshot works with monochrome mode

[Yasuhiro Kimura]

From: Yasuhiro Kimura <yasu at utahime.org>
Subject: Re: Installer of 20210225 snapshot works with monochrome mode
Date: Wed, 03 Mar 2021 00:43:24 +0900 (JST)

>> I created VirtualBox VM on Windows host and tried to make clean
>> install of 14-CURRENT with iso image of 20210225 snapshot
>> (FreeBSD-14.0-CURRENT-amd64-20210225-bf667f282a7-256946-disc1.iso). Then
>> installer worked with monochrome mode as following.
>> 
>> https://www.utahime.org/FreeBSD/install-snapshot-020210225.01.png
>> https://www.utahime.org/FreeBSD/install-snapshot-020210225.02.png
>> https://www.utahime.org/FreeBSD/install-snapshot-020210225.03.png
>> 
>> If I start `bsdinstall` after installation is completed, then it works
>> normal color mode. So it seems bug of install image.
> 
> I tried 20210218 snapshot and the problem didn't happen. So I'm now
> bisecting and will report which commit causes it.

According to the result of bisecting, following commit is the cause of
the problem.

----------------------------------------------------------------------
commit 77e1ccbee3ed6c837929e4e232fd07f95bfc8294
Author:     Rick Parrish <unitrunker at gmail.com>
AuthorDate: Sun Feb 7 07:15:21 2021 +0100
Commit:     Baptiste Daroussin <bapt at FreeBSD.org>
CommitDate: Tue Feb 23 11:16:53 2021 +0100

    rc: implement parallel boot
    
    take advantage of the rcorder -p argument to implement parallel
    booting in rc.
    
    According to the author non scientific tests:
    on a Core 2 Duo with spinning disk:
    
    | Services enabled | before | after | saving |
    | 0                | 8s     | 8s    | 0      |
    | 1                | 13s    | 13s   | 0      |
    | 2                | 17s    | 13s   | 5      |
    | 3                | 23s    | 13s   | 10     |
    | 4                | 28s    | 13s   | 15     |
    | 5                | 33s    | 13s   | 20     |
    
    PR:             249192
    MFC after:      3 weeks
----------------------------------------------------------------------

When I saw it I remembered some fixes related to it were committed. So
I tried release build with aff9b9ee89 of main and tested created iso
image. But the problem still happens.

I submitted the problem to Bugzilla as following bug report.

Bug 253997 - Installer of 20210225 snapshot works with monochrome mode
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=253997

---
Yasuhiro Kimura