The interlaced and double line mode bits should not be copied to new
console when the console is switched. Otherwise, the new console may be
set to incorrect refresh rate.
Also, the x and y offsets does not need to be copied.
Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Another addendum to commit c9e587abfd
("vt: fix background color on line feed").
fbcon still was not doing the right thing (read: continued to do old
behavior). fbcon_clear() seems to clear the new line (e.g. where your new
prompt appears after doing echo -en "\e[42mfoo\n"), while scr_memsetw clears
the previous one only (where "foo" appears). So just temporarily set the
video_erase_char to the scrl_erase_char so that fbcon_clear does the right
thing.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Addendum to commit c9e587abfd ("vt: fix
background color on line feed").
vc->vc_scrl_erase_char was not updated when fbcon switches between
256- and 512-glyph fonts.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A command that causes a line feed while a background color is active,
such as
perl -e 'print "x" x 60, "\e[44m", "x" x 40, "\e[0m\n"'
and
perl -e 'print "x" x 40, "\e[44m\n", "x" x 40, "\e[0m\n"'
causes the line that was started as a result of the line feed to be completely
filled with the currently active background color instead of the default
color.
When scrolling, part of the current screen is memcpy'd/memmove'd to the new
region, and the new line(s) that will appear as a result are cleared using
memset. However, the lines are cleared with vc->vc_video_erase_char, causing
them to be colored with the currently active background color. This is
different from X11 terminal emulators which always paint the new lines with
the default background color (e.g. `xterm -bg black`).
The clear operation (\e[1J and \e[2J) also use vc_video_erase_char, so a new
vc->vc_scrl_erase_char is introduced with contains the erase character used
for scrolling, which is built from vc->vc_def_color instead of vc->vc_color.
Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: Krzysztof Helt <krzysztof.h1@wp.pl>
Cc: Antonino Daplas <adaplas@gmail.com>
Cc: Antonino A. Daplas <adaplas@gmail.com>
Cc: Antonino Daplas <adaplas@pol.net>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Adrian Bunk <bunk@stusta.de>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use __u32 for max_len to match the declaration of length in the struct
fb_bitfield.
Suppresses sparse shadowed variable warnings from the nested max()
macros:
drivers/video/console/fbcon.h:130:8: warning: symbol '_x' shadows an earlier one
drivers/video/console/fbcon.h:130:8: originally declared here
drivers/video/console/fbcon.h:130:8: warning: symbol '_x' shadows an earlier one
drivers/video/console/fbcon.h:130:8: originally declared here
drivers/video/console/fbcon.h:130:8: warning: symbol '_y' shadows an earlier one
drivers/video/console/fbcon.h:130:8: originally declared here
[akpm@linux-foundation.org: fix constness]
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The kernel.h macro DIV_ROUND_UP performs the computation (((n) + (d) - 1) /
(d)) but is perhaps more readable.
An extract of the semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@haskernel@
@@
#include <linux/kernel.h>
@depends on haskernel@
expression n,d;
@@
(
- (n + d - 1) / d
+ DIV_ROUND_UP(n,d)
|
- (n + (d - 1)) / d
+ DIV_ROUND_UP(n,d)
)
@depends on haskernel@
expression n,d;
@@
- DIV_ROUND_UP((n),d)
+ DIV_ROUND_UP(n,d)
@depends on haskernel@
expression n,d;
@@
- DIV_ROUND_UP(n,(d))
+ DIV_ROUND_UP(n,d)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add architecture support for the MN10300/AM33 CPUs produced by MEI to the
kernel.
This patch also adds board support for the ASB2303 with the ASB2308 daughter
board, and the ASB2305. The only processor supported is the MN103E010, which
is an AM33v2 core plus on-chip devices.
[akpm@linux-foundation.org: nuke cvs control strings]
Signed-off-by: Masakazu Urade <urade.masakazu@jp.panasonic.com>
Signed-off-by: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The current attr_fgcol_ec / attr_bgcol_ec macros do a simple shift of bits
to get the color from vc_video_erase_char. For a monochrome display
however the attribute does not contain any color, only attribute bits.
Furthermore the reverse bit is lost because it is shifted out, the
resulting color is always 0.
This can bee seen on a monochrome console either directly or by setting it
to inverse mode via "setterm -inversescreen on" . Text is written with
correct color, fb_fillrects from a bit_clear / bit_clear_margins will get
wrong colors.
Signed-off-by: Thomas Pfaff <tpfaff@pcs.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After the APUS removal, some code can be removed.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Karsten Keil <kkeil@suse.de>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch disables the VGA text console for AVR32 architecture since
it does not provide the vga.h include file.
AVR32 users should use framebuffer console instead if they need a
console on an attached display.
Signed-off-by: Hans-Christian Egtvedt <hcegtvedt@atmel.com>
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Most of these fixes were already submitted for old kernel versions, and were
approved, but for some reason they never made it into the releases.
Because this is a consolidation of a couple old missed patches, it touches both
Kconfigs and documentation texts.
Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Fix build broken by accaa24c49:
CC drivers/video/console/newport_con.o
drivers/video/console/newport_con.c: In function 'newport_show_logo':
drivers/video/console/newport_con.c:111: error: assignment of read-only location
drivers/video/console/newport_con.c:111: warning: assignment makes integer from pointer without a cast
drivers/video/console/newport_con.c:112: error: assignment of read-only location
drivers/video/console/newport_con.c:112: warning: assignment makes integer from pointer without a cast
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As reported in Bugzilla Bug 9093, upon switching to X, a small rectangular
cursor can still be seen blinking in the upper left part of the screen. It is
fbcon's text cursor. This is caused by a strange ioctl(..., KDSETMODE,
KD_TEXT) call done by something in userspace, perhaps by X itself, while the
tty is still in graphics mode. And when the tty is in KD_TEXT mode, the
cursor timer is restarted.
Although this is a userspace problem, we can work around it by delaying the
restart of the cursor timer until an fbcon_switch() is called. In other
words, the cursor timer will not be restarted even if a KD_TEXT mode switch is
requested.
Regression potential: Present but low
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add logo.nologo kernel boot option to disable the logo in order to provide
more screen space for kernel messages; especially useful when debugging and
screen space is more critical.
newport_con driver changes are untested.
[akpm@linux-foundation.org: cleanups, coding-style fixes]
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Various console drivers are able to resize the screen via the con_resize()
hook. This hook is also visible in userspace via the TIOCWINSZ, VT_RESIZE and
VT_RESIZEX ioctl's. One particular utility, SVGATextMode, expects that
con_resize() of the VGA console will always return success even if the
resulting screen is not compatible with the hardware. However, this
particular behavior of the VGA console, as reported in Kernel Bugzilla Bug
7513, can cause undefined behavior if the user starts with a console size
larger than 80x25.
To work around this problem, add an extra parameter to con_resize(). This
parameter is ignored by drivers except for vgacon. If this parameter is
non-zero, then the resize request came from a VT_RESIZE or VT_RESIZEX ioctl
and vgacon will always return success. If this parameter is zero, vgacon will
return -EINVAL if the requested size is not compatible with the hardware. The
latter is the more correct behavior.
With this change, SVGATextMode should still work correctly while in-kernel and
stty resize calls can expect correct behavior from vgacon.
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch replaces <asm/uaccess.h> with <linux/uaccess.h> after the
checkpatch.pl hint. The include of <asm/uaccess.h> is removed if the driver
does not use it.
Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Akpm's patch "newport_con warning fix" got me to look at the console drivers
again and one thing that I noticed was that none of the fonts was using ISO
initializers for it's fonts.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We better select a font when the newport driver is a module or the user
experience might suffer.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/kyle/parisc-2.6:
[PARISC] Add NOTES section
[PARISC] Use compat_sys_getdents
[PARISC] Do not allow STI_CONSOLE to be modular
[PARISC] Clean up sti_flush
[PARISC] Add dummy isa_(bus|virt)_to_(virt|bus) inlines
[PARISC] Add empty <asm-parisc/vga.h>
sti_flush is supposed to flush the caches so we can execute the STI rom
we copied to memory. Anything more than flush_icache_range is overkill.
Fixes a missing symbol when built as a module.
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
drivers/video/console/newport_con.c: In function `newport_console_init':
drivers/video/console/newport_con.c:743: warning: return makes integer from pointer without a cast
Although one wonders whether that should have been -ENODEV...
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix compile warning ('map_override unused') if fbcon is compiled as a module
and CONFIG_FRAMEBUFFER_CONSOLE_DETECT_PRIMARY=n.
[akpm@linux-foundation.org: cleanup]
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported in: Bugzilla Bug 8727
Fix typo and bogus logic in get_default_font(). The bug results in
get_default_font() returning a font that may not be displayed properly by a
framebuffer driver.
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix following section mismatch warning:
WARNING: vmlinux.o(.text+0x121e62): Section mismatch: reference to .init.text:__alloc_bootmem (between 'vgacon_startup' and 'vgacon_scrolldelta')
Browsing the code it seems that vgacon_scrollback_startup() is only called
during the init phase so the reference to the .init.text section is OK.
Teach modpost not to warn using ___init_refok.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This allows for proper console unregistration via the VT layer, and updates
the FB layer to use it. This makes debugging new console drivers much easier,
since you can properly clean them up before unloading.
[adaplas]
unregister_framebuffer() is typically called as part of the driver's
module_exit(). Doing so otherwise will freeze the machine as the VT layer is
holding reference counts on fbcon, and fbcon on the driver. With this change,
it allows unregister_framebuffer() to be called safely anywhere as needed.
Additions from the original: If multiple drivers are used by fbcon, and if
one of them unregisters, a driver will take over the consoles vacated by the
outgoing one (via set_con2fb_map). Once only the outgoing driver remains,
then fbcon will unbind from the VT layer (if CONFIG_HW_CONSOLE_UNBINDING is
set to y).
It is important that these drivers implement fb_open() and fb_release()
just to ensure that no other process is using the driver. Likewise, these
drivers _must_ check the return value of unregister_framebuffer().
[akpm@linux-foundation.org: make fbcon_unbind() stub inline]
Signed-off-by: Jesse Barnes <jesse.barnes@intel.com>
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use set_con2fb_map() to select the primary display driver instead of using
unbind_con_driver() and bind_con_driver(). Using the former is much simpler
and safer than the current one.
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
set_con2fb_map() has regressed for some time. Using fbcon=map:01, for
example, works only if there is only 1 working framebuffer. Trying to do a
set_con2fb_map() on a non-allocated vc will freeze the system.
- ensure that succeeding drivers after the first gets mapped to the console
- remove fbcon_preset_display() and modify fbcon_set_display() to include the
former's functionality
- ensure that binding and unbinding succeeds if multiple drivers are mapped to
the console
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Allow fbcon to select the primary display adapter using the
fb_is_primary_device() arch-specific helper. If a a primary adapter is
detected, fbcon will unbind the old adapter from the VT layer, then rebind
using the new adapter. This requires that bind_/unbind_con_driver() be made
public.
Because this feature may produce unexpected behavior (from the user's POV),
this must be explicitly enabled in Kconfig.
[akpm@linux-foundation.org: export unbind_con_driver]
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Port fbcon.c to use struct device from using struct class_device
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add sysfs attribute to enable or disable cursor blinking. This will also
disable cursor blinking if the VT layer's softcursor is active. These changes
are required to enable some machines to enter low-power states properly.
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch replaces the current SCROLL_MOVE method with smarter method using
the same logic as the SCROLL_REDRAW method. This brings these two methods
much closer in performance and benefits all framebuffers which uses the
SCROLL_MOVE method.
[adaplas]
- remove unnecessary char attribute checking
- whitespace cleanups and 80-column line fixes
Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* master.kernel.org:/pub/scm/linux/kernel/git/kyle/parisc-2.6: (30 commits)
[PARISC] remove global_ack_eiem
[PARISC] Fix kernel panic in check_ivt
[PARISC] Fix bug when syscall nr is __NR_Linux_syscalls
[PARISC] be more defensive in process.c::get_wchan
[PARISC] fix "reduce size of task_struct on 64-bit machines" fallout
[PARISC] fix null ptr deref in unwind.c
[PARISC] fix trivial spelling nit in asm/linkage.h
[PARISC] remove remnants of parisc-specific softirq code
[PARISC] fix section mismatch in smp.c
[PARISC] fix "ENTRY" macro redefinition
[PARISC] Wire up utimensat/signalfd/timerfd/eventfd syscalls
[PARISC] fix section mismatch in superio serial drivers
[PARISC] fix section mismatch in parisc eisa driver
[PARISC] fix section mismatches in arch/parisc/kernel
[PARISC] fix section mismatch in ccio-dma
[PARISC] fix section mismatch in parisc STI video drivers
[PARISC] fix section mismatch in parport_gsc
[PARISC] fix lasi_82596 build
[PARISC] Build fixes for power.c
[PARISC] kobject is embedded in subsys, not kset
...
Fix the following warnings in promcon:
WARNING: o-sparc64/drivers/video/console/built-in.o(.text+0x480): Section mismatch: reference to .init.data:promfont_unitable (between 'promcon_init_unimap' and 'promcon_init')
WARNING: o-sparc64/drivers/video/console/built-in.o(.text+0x488): Section mismatch: reference to .init.data:promfont_unitable (between 'promcon_init_unimap' and 'promcon_init')
WARNING: o-sparc64/drivers/video/console/built-in.o(.text+0x48c): Section mismatch: reference to .init.data:promfont_unicount (between 'promcon_init_unimap' and 'promcon_init')
WARNING: o-sparc64/drivers/video/console/built-in.o(.text+0x490): Section mismatch: reference to .init.data:promfont_unicount (between 'promcon_init_unimap' and 'promcon_init')
The warnings happens because the function: promcon_init_unimap()
references promfont_unitable and promfont_unicount which are marked
__initdata by the conmakehash command in the drivers/video/console/Makefile
Fix the warning by removing the __initdata marker on the two variables.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move the forward declaration of fb_class from drivers/video/console/fbcon.h to
<linux/fb.h>, together with the other forward declarations related to
drivers/video/fbmem.c.
This kills the following sparse warning:
| drivers/video/fbmem.c:1363:14: warning: symbol 'fb_class' was not declared. Should it be static?
Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Refine SCREEN_INFO sanity check for vgacon initialization.
Checking video mode field only to see whenever SCREEN_INFO is
initialized is not enougth, in some cases it is zero although
a vga card is present. Lets additionally check cols and lines.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>
Cc: Alan <alan@lxorguk.ukuu.org.uk>
Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove the obsolete "if [ ]" construct from the video console Kconfig
file.
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Acked-by: James Simmons <jsimmons@infradead.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Many files include the filename at the beginning, serveral used a wrong one.
Signed-off-by: Uwe Kleine-König <ukleinek@informatik.uni-freiburg.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Reported by James Pearson as:
boot to run level 3
if not root, then make sure /dev/console is writeable
login and type:
setterm -blank 0
start X
type into an xterm:
while true; do echo "" > /dev/console; usleep 100000; done
while the above loop is running switch to the text console and back
again (Ctrl-Alt-F1 then Ctrl-Alt-F7)
... and the screen will be shifting (and wrapping) to the left.
This problem stems from continuously writing text to the system console (which
is in KD_TEXT mode) while the foreground console is in KD_GRAPHICS
mode. Somewhere along the way, console printing got confused and omitted the
KD_GRAPHICS/KD_TEXT test. Thus, vgacon attempted to scroll the screen of X,
which causes X to shift.
Fix by disallowing vgacon to touch the hardware when the vc is in KD_GRAPHICS
mode. A definitive fix entails a full audit of the console code.
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Check the console-to-fb mapping in fbcon_get_requirement(), otherwise the
value returned may not be valid for the driver.
- Minor cleanup
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>