Booting a 64-vcpu KVM guest, with CONFIG_PREEMPT_VOLUNTARY,
can result in a soft lockup:
BUG: soft lockup - CPU#41 stuck for 67s! [setfont:1505]
RIP: 0010:[<ffffffff812c48da>]
[<ffffffff812c48da>] vgacon_do_font_op.clone.0+0x1ba/0x550
This is due to the 8192 (cmapsz) IO operations taking longer than expected
due to lock contention in QEMU.
Add conditional resched points in between writes allowing other tasks to
execute.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
When we switch from 256->512 byte font rendering mode, it means the
current contents of the screen is being reinterpreted. The bit that holds
the high bit of the 9-bit font, may have been previously set, and thus
the new font misrenders.
The problem case we see is grub2 writes spaces with the bit set, so it
ends up with data like 0x820, which gets reinterpreted into 0x120 char
which the font translates into G with a circumflex. This flashes up on
screen at boot and is quite ugly.
A current side effect of this patch though is that any rendering on the
screen changes color to a slightly darker color, but at least the screen
no longer corrupts.
v2: as suggested by hpa, always clear the attribute space, whether we
are are going to or from 512 chars.
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
The vga_lock lock can be taken in atomic context and therefore
cannot be preempted on -rt - annotate it.
In mainline this change documents the low level nature of
the lock - otherwise there's no functional difference. Lockdep
and Sparse checking will work as usual.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Now vgacon_scrollback_startup() uses slab, not bootmem,
the comment above it is obsolete, so does __init_refok.
Signed-off-by: WANG Cong <amwang@redhat.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
It seems there is a small problem of VGA palette corruption on EFI
machine. When the kernel initializes the architecture, it checks if the
machine is a EFI machine and assumes that a VGA console can exist.
When it initializes the console in vgacon_startup it checks if it can
really use the VGA console. I think this is where a check is missing.
Currently, the function can fail if a VESA boot mode is detected but not if
a EFI boot mode was used.
Thus vgacon_startup() doesn't fail and initialize the video card for a real
VGA mode. This function changes the first 16entries of the VGA palette.
When the efifb driver kicks in, the palette is not restored to default
ramp value, thus the 16 first entry remain in a modified state. The
following patch prevent this corruption.
Signed-off-by: Yannick Heneault <yheneaul@matrox.com>
Cc: Dave Airlie <airlied@linux.ie>
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>
The big kernel lock has been removed from all these files at some point,
leaving only the #include.
Remove this too as a cleanup.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
vgacon_do_font_op releases and reacquires the BTM while holding
console_sem. This violates the rule that BTM has to be the
outer lock whenever we hold both.
There does not seem to be any reason to give up the BTM here,
so just stop doing that.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
As a preparation for replacing the big kernel lock
in the TTY layer, wrap all the callers in new
macros tty_lock, tty_lock_nested and tty_unlock.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
warning: symbol 'vgacon_text_mode_force' was not declared. Should it be static?
Signed-off-by: Thiago Farina <tfransosi@gmail.com>
Acked-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pass the vga cursor state to the vt layer, ensuring that we don't hide
the cursor when the bootloader has deliberately disabled it.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
LKML-Reference: <1258142222-16092-3-git-send-email-mjg@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Add support for setting a global default for whether or not a visible
cursor should be enabled when creating VCs. The default will be to do so,
unless overridden by the user at boot time or by a driver.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
LKML-Reference: <1258143251-5818-1-git-send-email-mjg@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
fbcon makes the (reasonable) assumption that it only needs to program the
hardware once, when fbcon_init() is called for the foreground console.
This doesn't always play well with vgacon because vgacon_deinit() is only
doing its job when the last console it owns is closed (when switching from
vgacon to fbcon, that's usually *after* fbcon_init() has set the new
mode).
Depending on the hardware this can cause the wrong framebuffer location to
be scanned out (e.g. reproduced on nv05 with the nouveau framebuffer
driver).
Signed-off-by: Francisco Jerez <currojerez@riseup.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fix the following 'make includecheck' warning:
drivers/video/console/vgacon.c: linux/slab.h is included more than once.
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: Martin Mares <mj@ucw.cz>
Cc: mchehab@infradead.org
Cc: Sam Ravnborg <sam@ravnborg.org>
LKML-Reference: <1247067624.4382.88.camel@ht.satnam>
Slab is initialized before the console subsystem so use the slab allocator in
vgacon_scrollback_startup().
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Uwe Geuder noted that he gets random bitmaps on a text console if he tried
to type extended characters (like the e acute). For him everything above
unicode 0xa0 was corrupted.
After some digging there seems to be a little culprit in vgacon since the
beginning of ages (well git). The function vgacon_font_get will store the
number of characters correctly in font->charcount but then calls to
vgacon_do_font_op(..., 0, 0). Which means only the lower 256 characters
are actually stored to the fontdata. The rest is left untouched. So the
next time that saved data is used, the garbled font appears. This happens
on every switch between text consoles.
Addresses https://bugs.launchpad.net/ubuntu/+source/linux/+bug/355057
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Tested-by: Uwe Geuder <ubuntuLp-ugeuder@sneakemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add mode setting support to the DRM layer.
This is a fairly big chunk of work that allows DRM drivers to provide
full output control and configuration capabilities to userspace. It was
motivated by several factors:
- the fb layer's APIs aren't suited for anything but simple
configurations
- coordination between the fb layer, DRM layer, and various userspace
drivers is poor to non-existent (radeonfb excepted)
- user level mode setting drivers makes displaying panic & oops
messages more difficult
- suspend/resume of graphics state is possible in many more
configurations with kernel level support
This commit just adds the core DRM part of the mode setting APIs.
Driver specific commits using these new structure and APIs will follow.
Co-authors: Jesse Barnes <jbarnes@virtuousgeek.org>, Jakob Bornecrantz <jakob@tungstengraphics.com>
Contributors: Alan Hourihane <alanh@tungstengraphics.com>, Maarten Maathuis <madman2003@gmail.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>
There's no point in checking diff == c->vc_rows, because it can be true
only when count == 0, but we already checked that. Additionally move
variables used only in one block to this block.
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Antonino Daplas <adaplas@gmail.com>
Acked-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>
This reverts commit c9e587abfd, and the
subsequent commits that fixed it up:
- afa9b649 "fbcon: prevent cursor disappearance after switching to 512
character font"
- d850a2fa "vt/fbcon: fix background color on line feed"
- 7fe3915a "vt/fbcon: update scrl_erase_char after 256/512-glyph font
switch"
by request of Alan Cox. Quoth Alan:
"Unfortunately it's wrong and its been causing breakages because
various apps like ncurses expect our previous (and correct)
behaviour."
Alexander sent out a similar patch.
Requested-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Tested-by: Jan Engelhardt <jengelh@medozas.de>
Cc: Alexander V. Lukyanov <lav@netis.ru>
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>
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>
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>
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>
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>
Add color support to the "underline" and "italic" attributes as in
OpenBSD/NetBSD-style (vt220) and xterm.
Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
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>
Avoid trying to set up vgacon if there's no vga hardware present.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Alan <alan@lxorguk.ukuu.org.uk>
Acked-by: Ingo Molnar <mingo@elte.hu>
After Al Viro (finally) succeeded in removing the sched.h #include in module.h
recently, it makes sense again to remove other superfluous sched.h includes.
There are quite a lot of files which include it but don't actually need
anything defined in there. Presumably these includes were once needed for
macros that used to live in sched.h, but moved to other header files in the
course of cleaning it up.
To ease the pain, this time I did not fiddle with any header files and only
removed #includes from .c-files, which tend to cause less trouble.
Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha,
arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig,
allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all
configs in arch/arm/configs on arm. I also checked that no new warnings were
introduced by the patch (actually, some warnings are removed that were emitted
by unnecessarily included header files).
Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- annotate some variables from vgacon.c and fbmem.c as __read_mostly
- move the mask[] array in fb_set_logo_truepalette() into the .rodata section
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
screen_info.h doesn't have anything to do with the tty layer and shouldn't be
included by tty.h. This patches removes the include and modifies all users to
directly include screen_info.h. struct screen_info is mainly used to
communicate with the console drivers in drivers/video/console. Note that this
patch touches every arch and I have no way of testing it. If there is a
mistake the worst thing that will happen is a compile error.
[akpm@osdl.org: fix arm build]
[akpm@osdl.org: fix alpha build]
Signed-off-by: Jon Smirl <jonsmir@gmail.com>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
MAX_NR_CONSOLES, fg_console, want_console and last_console are more of a
function of the VT layer than the TTY one. Moving these to vt.h and vt_kern.h
allows all of the framebuffer and VT console drivers to remove their
dependency on tty.h.
[akpm@osdl.org: fix alpha build]
Signed-off-by: Jon Smirl <jonsmir@gmail.com>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Based on an original patch from Ralf Baechle <ralf@linux-mips.org> and
Vivek Goyal <vgoyal@in.ibm.com>. This is needed in order to prepare for
changing the size of resources.
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
One of the limitations of the framebuffer console system is its inablity to
unload or detach itself from the console layer. And once it loads, it also
locks in framebuffer drivers preventing their unload. Although the con2fbmap
utility does provide a means to unload individual drivers, it requires that at
least one framebuffer driver is loaded for use by fbcon.
With this change, it is possible to detach fbcon from the console layer. If it
is detached, it will reattach the boot console driver (which is permanently
loaded) back to the console layer so the system can continue to work. As a
consequence, fbcon will also decrement its reference count of individual
framebuffer drivers, allowing all of these drivers to be unloaded even if
fbcon is still loaded.
Unless you use drivers that restores the display to text mode (rivafb and
i810fb, for example), detaching fbcon does require assistance from userspace
tools (ie, vbetools) for text mode to be restored completely. Without the
help of these tools, fbcon will leave the VGA console corrupted. The methods
that can be used will be described in Documentation/fb/fbcon.txt.
Because the vt layer also increments the module reference count for each
console driver, fbcon cannot be directly unloaded. It must be detached first
prior to unload.
Similarly, fbcon can be reattached to the console layer without having to
reload the module. A nice feature if fbcon is compiled statically.
Attaching and detaching fbcon is done via sysfs attributes. A class device
entry for fbcon is created in /sys/class/graphics. The two attributes that
controls this feature are detach and attach. Two other attributes that are
piggybacked under /sys/class/graphics/fb[n] that are fbcon-specific,
'con_rotate' and 'con_rotate_all' are moved to fbcon. They are renamed as
'rotate' and 'rotate_all' respectively.
Overall, this feature is a great help for developers working in the
framebuffer or console layer. There is not need to continually reboot the
kernel for every small change. It is also useful for regular users who wants
to choose between a graphical console or a text console without having to
reboot.
Example usage for x86:
/* start in text mode */
modprobe xxxfb
modprobe fbcon
/* graphical mode with fbcon using xxxfb */
echo 1 > /sys/class/graphics/fbcon/detach
/* back to text mode, will produce corrupt display unless vbetool is used */
rmmod xxxfb
modprobe yyyfb
/* back to graphical mode with fbcon using yyyfb */
Before trying out this feature, please read Documentation/fb/fbcon.txt.
This patch:
In order for fbcon to detach itself from the console layer, vgacon, which is a
boot console driver, must be fixed so it can retake the console multiple
times, not just during init. The following needs to be done:
- remove __init from the vgacon_startup, this is called again by
take_over_console().
- vc->rows and vc->cols are set manually by vgacon during init. After init,
vc_resize() can be used
- make sure the scrollback_buffer is not reallocated
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
VGA_MAP_MEM translates to ioremap() on some architectures. It makes sense
to do this to vga_vram_base, because we're going to access memory between
vga_vram_base and vga_vram_end.
But it doesn't really make sense to map starting at vga_vram_end, because
we aren't going to access memory starting there. On ia64, which always has
to be different, ioremapping vga_vram_end gives you something completely
incompatible with ioremapped vga_vram_start, so vga_vram_size ends up being
nonsense.
As a bonus, we often know the size up front, so we can use ioremap()
correctly, rather than giving it a zero size.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The scrollback buffer of the VGA console is located in VGA RAM. This RAM
is fixed in size and is very small. To make the scrollback buffer larger,
it must be placed instead in System RAM.
This patch adds this feature. The feature and the size of the buffer are
made as a kernel config option. Besides consuming kernel memory, this
feature will slow down the console by approximately 20%.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Jindrich Makovicka <makovick@kmlinux.fjfi.cvut.cz>
Cc: Martin Mares <mj@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This corrects cursor resize on ega boards: registers are write-only, so we
shouldn't even try to read them. And on ega, 31/30 produces a flat cursor.
Using 31/31 is better: except with 32 pixels high fonts, it shouldn't show
up.
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
EGA boards suck: they mostly have write-only registers. This is
particularly problematic for the overflow register: for being able to write
to it, we would have to handle vertical sync & such too, which (I'd say)
would potentially break a lot of configurations. Instead, just disabling
vertical resize for EGA boards is just nice enough (horizontal resize still
works).
Fixes http://bugzilla.kernel.org/show_bug.cgi?id=6106
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Cc: Rafal Olearski <olearski@mail2.kim.net.pl>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Reported from Redhat Bugzilla Bug 170450
"I updated to the development kernel and now during boot only the top of the
text is visable. For example the monitor screen the is the lines and I can
only see text in the asterisk area.
When doublescan mode is in use, scanlines must be doubled.
Thanks to Jason Dravet <dravet@hotmail.com> for reporting and testing.
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Reported by: Wayne E. Harlan
"[1.] One line summary of the problem:
When the kernel option "vga=1" is used, additional tty's (alt+control+Fx
with x=2,3,4,5, etc) do not provide the full 50 lines of output. The first
one does have 50 lines, however.
[2.] Full description of the problem/report:
These addtitional tty's show only 39 lines plus the top pixel of the 40-th
line. The remaining lines are black and not shown. Kernel version
2.6.13.4 does not show this problem."
This bug is caused by using a stale font height value on vgacon_init.
Booting with vga=1 gives an 80x50 screen with an 8x8 font. Somewhere
during the initialization, the font was changed to 8x9 and the first
vc was correctly resized to 80x44. However, the rest of the vc's were
not allocated yet, and when they were subsequently initialized, they
still used a font height of 8 (instead of 9) causing the mentioned bug.
Fix by saving the new font height to vga_video_font_height.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Some visually impaired people use hardware devices which directly read
the vga screen. When newt for instance asks to hide the cursor for
better visual aspect, the kernel puts the vga cursor out of the screen,
so that the cursor position can't be read by the hardware device. This
is a great loss for such people.
Here is a patch which uses the same technique as CUR_NONE for hiding the
cursor while still moving it.
Mario, you should apply it to the speakup kernel for access floppies
asap. I'll submit a 2.4 patch too.
Signed-off-by: samuel.thibault@ens-lyon.org
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch fixes a long-standing vgacon bug: characters with the bright bit
set were left on the screen and not blacked out. All I did was that I
lookuped up some examples on the net about setting the vga palette, and
added the call missing from the linux kernel, but included in all other
ones. It works for me.
You can test this by writing something with the bright set to the
console, for example:
echo -e "\e[1;31mhello there\e[0m"
and then wait for the console to blank itself (by default, after 10 mins
of inactivity), maybe making it faster using
setterm -blank 1
so you only have to wait 1 minute.
Signed-off-by: Pozsar Balazs <pozsy@uhulinux.hu>
Cc: James Simmons <jsimmons@infradead.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix bug 5441.
I didn't know about messy programs like svgatextmode... Couldn't this be
integrated in some linux/drivers/video/console/svgacon.c ?... So because
of the existence of the svgatextmode program, the kernel is not supposed to
touch to CRT_OVERFLOW/SYNC_END/DISP/DISP_END/OFFSET ?
Disabling the check in vgacon_resize() might help indeed, but I'm really
not sure whether it will work for any chipset: in my patch, CRT registers
are set at each console switch, since stty rows/cols apply to consoles
separately...
The attached solution is to keep the test, but if it fails, we assume that
the caller knows what it does (i.e. it is svgatextmode) and then disable
any further call to vgacon_doresize. Svgatextmode is usually used to
_expand_ the display, not to shrink it. And it is harmless in the case of
a too big stty rows/cols: the display will just be cropped. I tested it on
my laptop, and it works fine with svgatextmode.
A better solution would be that svgatextmode explicitely tells the kernel
not to care about video timing, but for this an interface needs be defined
and svgatextmode be patched.
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Reported by: walt <wa1ter@myrealbox.com>
"I routinely switch the console font during bootup to
8x8 so I can get 50 lines per screen. Until 09 Sept,
just changing to the small font automatically gave me
all 50 lines -- but now I'm only getting 25 lines even
with the small font. The bottom half of the screen
displays the text that already scrolled off the top."
This bug is due to an erroneous check in the recently added hook,
vgacon_resize(). It checks the new height against the original number of
rows of the console. Because the original number of rows depends on both
the scanline and the font height, check it instead against the
scanline/fontheight.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
