Date: Tue, 10 Mar 2020 05:14:49 +1000 From: Andy Farkas <andyf@andyit.com.au> Cc: freebsd-bugs@freebsd.org, freebsd-stable stable <freebsd-stable@freebsd.org> Subject: Re: vt [was: Re: [Bug 235564] INDEX.keymaps for vt contains "from-" keymaps but the files are missing] Message-ID: <8df70772-faee-bd07-612f-696e8a1d477c@andyit.com.au> In-Reply-To: <20200309150432.GR98340@kib.kiev.ua> References: <bug-235564-227@https.bugs.freebsd.org/bugzilla/> <bug-235564-227-XnaZH8PNlD@https.bugs.freebsd.org/bugzilla/> <d8e63de9-0da5-0b02-09b4-01e23e9afdf3@andyit.com.au> <CAPyFy2CJ1-jJx95XhdraRxo4Nk%2BFP3b60ZZtpxjN%2Box3j4jGsg@mail.gmail.com> <20200309150432.GR98340@kib.kiev.ua>
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On 2020-03-10 01:04, Konstantin Belousov wrote: > Take a look at r334530. "or the user really hates this feature and can't wait to turn it off" Excellently explained by Bruce as usual: "Revision 314641 - (view) (download) (annotate) - [select for diffs] Modified Sat Mar 4 06:19:12 2017 UTC (3 years ago) by bde File length: 107771 byte(s) Diff to previous 312910 Colorize syscons kernel console output according to a table indexed by the CPU number. This was originally for debugging near-deadlock conditions where multiple CPUs either deadlock or scramble each other's output trying to report the problem, but I found it interesting and sometimes useful for ordinary kernel messages. Ordinary kernel messages shouldn't be interleaved, but if they are then the colorization makes them readable even if the interleaving is for every character (provided the CPU printing each message doesn't change). The default colors are 8-15 starting at 15 (bright white on black) for CPU 0 and repeating every 8 CPUs. This works best with 8 CPUs. Non-bright colors and nonzero background colors need special configuration to avoid unreadable and ugly combinations so are not configured by default. The next bright color after 15 is 8 (bright black = dark gray) is not very readable but is the only other color used with 2 CPUs. After that the next bright color is 9 (bright blue) which is not much brighter than bright black, but is used with 3+ CPUs. Other bright colors are brighter. Colorization is configured by default so that it gets tested. It can only be turned off by configuring SC_KERNEL_CONS_ATTR to anything other than FG_WHITE. After booting, all colors can be changed using the syscons.kattr sysctl. This is a SYSCTL_OPAQUE, and no utility is provided to change it (sysctl only displays it). The default colors work in all VGA modes that I could test. In 2-color graphics modes, all 8 bright colors are displayed as bright white, so the colorization has no effect, but anything with a nonzero background gives white on white unless the foreground is zero. I don't have an mono or VGA grayscale hardware to test on. Support for mono mode seems to have never worked right in syscons (I think bright white gives white underline with either bold or bright), but VGA grayscale should work better than 2-color graphics." RIP https://photos.app.goo.gl/YiVmFtWiK8Niy3Fw6 -andyf
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