Files
linux-cryptodev-2.6/drivers/video/fbdev/omap2/omapfb/Kconfig
Thomas Zimmermann 701d2054fa fbdev: Make support for userspace interfaces configurable
Add Kconfig option CONFIG_FB_DEVICE and make the virtual fbdev
device optional. If the new option has not been selected, fbdev
does not create files in devfs, sysfs or procfs.

Most modern Linux systems run a DRM-based graphics stack that uses
the kernel's framebuffer console, but has otherwise deprecated fbdev
support. Yet fbdev userspace interfaces are still present.

The option makes it possible to use the fbdev subsystem as console
implementation without support for userspace. This closes potential
entry points to manipulate kernel or I/O memory via framebuffers. It
also prevents the execution of driver code via ioctl or sysfs, both
of which might allow malicious software to exploit bugs in the fbdev
code.

A small number of fbdev drivers require struct fbinfo.dev to be
initialized, usually for the support of sysfs interface. Make these
drivers depend on FB_DEVICE. They can later be fixed if necessary.

v3:
	* effect -> affect in Kconfig help (Daniel)
v2:
	* set FB_DEVICE default to y (Geert)
	* comment on {get,put}_device() (Sam)
	* Kconfig fixes (Sam)
	* add TODO item about FB_DEVICE dependencies (Sam)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230613110953.24176-39-tzimmermann@suse.de
2023-06-27 09:58:51 +02:00

42 lines
949 B
Plaintext

# SPDX-License-Identifier: GPL-2.0-only
config OMAP2_VRFB
bool
menuconfig FB_OMAP2
tristate "OMAP2+ frame buffer support"
depends on FB
depends on FB_DEVICE
depends on DRM_OMAP = n
depends on GPIOLIB
select FB_OMAP2_DSS
select OMAP2_VRFB if ARCH_OMAP2 || ARCH_OMAP3
select FB_CFB_FILLRECT
select FB_CFB_COPYAREA
select FB_CFB_IMAGEBLIT
help
Frame buffer driver for OMAP2+ based boards.
if FB_OMAP2
config FB_OMAP2_DEBUG_SUPPORT
bool "Debug support for OMAP2+ FB"
default y
depends on FB_OMAP2
help
Support for debug output. You have to enable the actual printing
with 'debug' module parameter.
config FB_OMAP2_NUM_FBS
int "Number of framebuffers"
range 1 10
default 3
depends on FB_OMAP2
help
Select the number of framebuffers created. OMAP2/3 has 3 overlays
so normally this would be 3.
source "drivers/video/fbdev/omap2/omapfb/dss/Kconfig"
source "drivers/video/fbdev/omap2/omapfb/displays/Kconfig"
endif