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authorPeter Rosin <peda@axentia.se>2018-12-20 19:13:07 +0100
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2019-02-12 19:47:15 +0100
commit6584e6c004357aaecf41d5108d691e347ebc6d07 (patch)
treeaaedfb3128a400d8953e86e359763606a16a9fc2 /drivers/video
parent54541a75bfb6fd9659c1321a490554f4cb99b286 (diff)
fbdev: fbmem: behave better with small rotated displays and many CPUs
[ Upstream commit f75df8d4b4fabfad7e3cba2debfad12741c6fde7 ] Blitting an image with "negative" offsets is not working since there is no clipping. It hopefully just crashes. For the bootup logo, there is protection so that blitting does not happen as the image is drawn further and further to the right (ROTATE_UR) or further and further down (ROTATE_CW). There is however no protection when drawing in the opposite directions (ROTATE_UD and ROTATE_CCW). Add back this protection. The regression is 20-odd years old but the mindless warning-killing mentality displayed in commit 34bdb666f4b2 ("fbdev: fbmem: remove positive test on unsigned values") is also to blame, methinks. Fixes: 448d479747b8 ("fbdev: fb_do_show_logo() updates") Signed-off-by: Peter Rosin <peda@axentia.se> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: Fabian Frederick <ffrederick@users.sourceforge.net> Cc: Geert Uytterhoeven <geert+renesas@glider.be> cc: Geoff Levand <geoff@infradead.org> Cc: James Simmons <jsimmons@users.sf.net> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/video')
-rw-r--r--drivers/video/fbdev/core/fbmem.c8
1 files changed, 6 insertions, 2 deletions
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
index 20405421a5ed..77cee99fc36c 100644
--- a/drivers/video/fbdev/core/fbmem.c
+++ b/drivers/video/fbdev/core/fbmem.c
@@ -435,7 +435,9 @@ static void fb_do_show_logo(struct fb_info *info, struct fb_image *image,
image->dx += image->width + 8;
}
} else if (rotate == FB_ROTATE_UD) {
- for (x = 0; x < num; x++) {
+ u32 dx = image->dx;
+
+ for (x = 0; x < num && image->dx <= dx; x++) {
info->fbops->fb_imageblit(info, image);
image->dx -= image->width + 8;
}
@@ -447,7 +449,9 @@ static void fb_do_show_logo(struct fb_info *info, struct fb_image *image,
image->dy += image->height + 8;
}
} else if (rotate == FB_ROTATE_CCW) {
- for (x = 0; x < num; x++) {
+ u32 dy = image->dy;
+
+ for (x = 0; x < num && image->dy <= dy; x++) {
info->fbops->fb_imageblit(info, image);
image->dy -= image->height + 8;
}