Ruby redux

[Zoltan B. <zb...@fr...>]

Hi,

as large console cleanups went into the -mm tree and those cleanups
are also part of the Ruby tree, I thought I look at the Ruby tree
and port it to 2.6.11-rc4 + the following 4 patches:

1. cleanup-vc-array-access.patch
2. remove-console_macrosh.patch
3. merge-vt_struct-into-vc_data.patch
4. merge-vt_struct-into-vc_data-fix.patch

In the porting, I followed these rules:
- no major cleanups, including:
   - no function shuffling around
   - no function and variable renames
- no DECVTE, keep the old Linux terminal emulation.

The only cleanup I applied was the redraw_screen() function
splitup to update_screen() and switch_screen() so they can be
static where they are used.

The result is a very straightforward patch that is about 18K smaller
than the first two cleanup patches added (~ 142000 bytes vs ~ 160000
bytes).

The catch is that it doesn't boot up successfully despite I tried
to follow the changes in the Ruby tree exactly. With only the VGA
console, I got a message about "unable to open initial console"
the SELinux messages and booting stopped there. With "dumbcon=3D1",
I got an oops with this stacktrace:

init
vty_init
dumb_console_init
dumbcon_add
vt_map_display

and I also got two messages:

unblank_screen: tty not allocated ??

Maybe it rings a bell for someone and can fix it. I expect at most
two one-liners over this patch to have a working Ruby kernel.

I Cc-ed all interested parties, including Roman Zippel who expressed
interest to look into the Ruby tree after all these cleanups went
mainline. Happy hacking, Roman! :-)

Best regards,
Zolt=E1n B=F6sz=F6rm=E9nyi