kernel/linux.git/drivers/video/fbdev/core/fb_cmdline.c, branch v6.12.80

fbdev: Fix logic error in "offb" name match

2025-10-19T14:33:49+00:00

commit 15df28699b28d6b49dc305040c4e26a9553df07a upstream. A regression was reported to me recently whereby /dev/fb0 had disappeared from a PowerBook G3 Series "Wallstreet". The problem shows up when the "video=ofonly" parameter is passed to the kernel, which is what the bootloader does when "no video driver" is selected. The cause of the problem is the "offb" string comparison, which got mangled when it got refactored. Fix it. Cc: stable@vger.kernel.org Fixes: 93604a5ade3a ("fbdev: Handle video= parameter in video/cmdline.c") Reported-and-tested-by: Stan Johnson Signed-off-by: Finn Thain Signed-off-by: Helge Deller Signed-off-by: Greg Kroah-Hartman

fbdev: Handle video= parameter in video/cmdline.c

2023-02-20T13:56:48+00:00

Handle the command-line parameter video= in video/cmdline.c. Implement the fbdev helper fb_get_options() on top. Will allows to handle the kernel parameter in DRM without fbdev dependencies. Note that __video_get_options() has the meaning of its return value inverted compared to fb_get_options(). The new helper returns true if the adapter has been enabled, and false otherwise. There is the ofonly parameter, which disables output for non-OF-based framebuffers. It is only for offb and looks like a workaround. The actual purpose it not clear to me. Use 'video=off' or 'nomodeset' instead. Signed-off-by: Thomas Zimmermann Reviewed-by: Javier Martinez Canillas Link: https://patchwork.freedesktop.org/patch/msgid/20230209135509.7786-9-tzimmermann@suse.de

fbdev: Move option-string lookup into helper

2023-02-20T13:56:47+00:00

Move the lookup of the option string into an internal helper. No functional changes. Signed-off-by: Thomas Zimmermann Reviewed-by: Javier Martinez Canillas Link: https://patchwork.freedesktop.org/patch/msgid/20230209135509.7786-8-tzimmermann@suse.de

fbdev: Unexport fb_mode_option

2023-02-20T13:56:46+00:00

There are no external users of fb_mode_option. Unexport the variable and declare it static. Signed-off-by: Thomas Zimmermann Reviewed-by: Javier Martinez Canillas Link: https://patchwork.freedesktop.org/patch/msgid/20230209135509.7786-7-tzimmermann@suse.de

fbdev: Support NULL for name in option-string lookup

2023-02-20T13:56:43+00:00

Ignore the per-driver video options if no driver name has been specified to fb_get_option(). Return the global options in this case. Signed-off-by: Thomas Zimmermann Reviewed-by: Javier Martinez Canillas Link: https://patchwork.freedesktop.org/patch/msgid/20230209135509.7786-4-tzimmermann@suse.de

fbdev: Transfer video= option strings to caller; clarify ownership

2023-02-20T13:56:42+00:00

In fb_get_options(), always duplicate the returned option string and transfer ownership of the memory to the function's caller. Until now, only the global option string got duplicated and transferred to the caller; the per-driver options were owned by fb_get_options(). In the end, it was impossible for the function's caller to detect if it had to release the string's memory buffer. Hence, all calling drivers leak the memory buffer. The leaks have existed ever since, but drivers only call fb_get_option() once as part of module initialization. So the amount of leaked memory is not significant. Fix the semantics of fb_get_option() by unconditionally transferring ownership of the memory buffer to the caller. Later patches can resolve the memory leaks in the fbdev drivers. Signed-off-by: Thomas Zimmermann Reviewed-by: Javier Martinez Canillas Link: https://patchwork.freedesktop.org/patch/msgid/20230209135509.7786-3-tzimmermann@suse.de

fbdev: Fix contact info in fb_cmdline.c

2023-02-20T13:56:41+00:00

Fix Daniel's email address. No functional changes. Signed-off-by: Thomas Zimmermann Cc: Daniel Vetter Reviewed-by: Javier Martinez Canillas Link: https://patchwork.freedesktop.org/patch/msgid/20230209135509.7786-2-tzimmermann@suse.de

video/fbdev: refactor video= cmdline parsing

2019-02-08T18:24:47+00:00

Make the video_setup() function slightly easier to read by removing the repeated checks for !global. Remove the misleading return value comment while at it. I'm slightly hesitant to change any of this, but here goes anyway, with hopes that the next person to have to look at this has it a wee bit easier. Signed-off-by: Jani Nikula Reviewed-by: Daniel Vetter Signed-off-by: Bartlomiej Zolnierkiewicz

video/fbdev: Always built-in video= cmdline parsing

2014-08-06T12:50:02+00:00

In drm/i915 we want to get at the video= cmdline modes even when we don't have fbdev support enabled, so that users can always override the kernel's initial mode selection. But that gives us a direct depency upon the parsing code in the fbdev subsystem. Since it's so little code just extract these 2 functions and always build them in. Whiel at it fix the checkpatch fail in this code. v2: Also move fb_mode_option. Spotted by the kbuild. v3: Review from Geert: - Keep the old copyright notice from fb_mem.c, although I have no idea what exactly applies. - Only compile this when needed. Cc: Geert Uytterhoeven Cc: Plagniol-Villard Cc: Tomi Valkeinen Cc: linux-fbdev@vger.kernel.org Signed-off-by: Daniel Vetter -- I prefer if we can merge this through drm-next since we'll use it there in follow-up patches. -Daniel