This is a note to let you know that I've just added the patch titled
fbcon: set_con2fb_map needs to set con2fb_map!
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
fbcon-set_con2fb_map-needs-to-set-con2fb_map.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From fffb0b52d5258554c645c966c6cbef7de50b851d Mon Sep 17 00:00:00 2001
From: Daniel Vetter <daniel.vetter@xxxxxxxx>
Date: Wed, 12 Apr 2023 17:31:46 +0200
Subject: fbcon: set_con2fb_map needs to set con2fb_map!
From: Daniel Vetter <daniel.vetter@xxxxxxxx>
commit fffb0b52d5258554c645c966c6cbef7de50b851d upstream.
I got really badly confused in d443d9386472 ("fbcon: move more common
code into fb_open()") because we set the con2fb_map before the failure
points, which didn't look good.
But in trying to fix that I moved the assignment into the wrong path -
we need to do it for _all_ vc we take over, not just the first one
(which additionally requires the call to con2fb_acquire_newinfo).
I've figured this out because of a KASAN bug report, where the
fbcon_registered_fb and fbcon_display arrays went out of sync in
fbcon_mode_deleted() because the con2fb_map pointed at the old
fb_info, but the modes and everything was updated for the new one.
Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxxx>
Reviewed-by: Javier Martinez Canillas <javierm@xxxxxxxxxx>
Acked-by: Helge Deller <deller@xxxxxx>
Tested-by: Xingyuan Mo <hdthky0@xxxxxxxxx>
Fixes: d443d9386472 ("fbcon: move more common code into fb_open()")
Reported-by: Xingyuan Mo <hdthky0@xxxxxxxxx>
Cc: Thomas Zimmermann <tzimmermann@xxxxxxx>
Cc: Sam Ravnborg <sam@xxxxxxxxxxxx>
Cc: Xingyuan Mo <hdthky0@xxxxxxxxx>
Cc: Thomas Zimmermann <tzimmermann@xxxxxxx>
Cc: Helge Deller <deller@xxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> # v5.19+
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/video/fbdev/core/fbcon.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -846,10 +846,11 @@ static int set_con2fb_map(int unit, int
if (err)
return err;
- con2fb_map[unit] = newidx;
fbcon_add_cursor_work(info);
}
+ con2fb_map[unit] = newidx;
+
/*
* If old fb is not mapped to any of the consoles,
* fbcon should release it.
Patches currently in stable-queue which might be from daniel.vetter@xxxxxxxx are
queue-6.1/fbcon-fix-error-paths-in-set_con2fb_map.patch
queue-6.1/fbcon-set_con2fb_map-needs-to-set-con2fb_map.patch
queue-6.1/fbmem-reject-fb_activate_kd_text-from-userspace.patch
