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authorPeter Rosin <peda@axentia.se>2018-12-20 21:13:07 +0300
committerBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>2018-12-20 21:13:07 +0300
commitf75df8d4b4fabfad7e3cba2debfad12741c6fde7 (patch)
tree83873c05c5625bac04bdb8326d55f07e1c0b58ed /drivers/video
parentfdac751355cd76e049f628afe6acb8ff4b1399f7 (diff)
downloadlinux-f75df8d4b4fabfad7e3cba2debfad12741c6fde7.tar.xz
fbdev: fbmem: behave better with small rotated displays and many CPUs
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>
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 861bf8081619..7dd6924feaa8 100644
--- a/drivers/video/fbdev/core/fbmem.c
+++ b/drivers/video/fbdev/core/fbmem.c
@@ -436,7 +436,9 @@ 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;
}
@@ -448,7 +450,9 @@ 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;
}