From: Antonino A. Daplas Date: Tue, 22 Nov 2005 05:32:25 +0000 (-0800) Subject: [PATCH] fbcon: Console Rotation - Fix wrong shift calculation X-Git-Tag: v2.6.15-rc3~106 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b4627dea032ab1f6e472fcf030e28f22ea971f9b;p=linux-2.6 [PATCH] fbcon: Console Rotation - Fix wrong shift calculation The shift value (amount to shift the bitmap so first pixel starts at origin(0,0)) is incorrect. This causes corrupted characters or a kernel crash if fontwidth is not divisible by 8 at 270 degrees, or fontheight not divisible by 8 at 180 degrees. Report and part of the fix contributed by Knut Petersen. Signed-off-by: Antonino Daplas Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/drivers/video/console/fbcon_rotate.h b/drivers/video/console/fbcon_rotate.h index 90c672096c..e504fbf5c6 100644 --- a/drivers/video/console/fbcon_rotate.h +++ b/drivers/video/console/fbcon_rotate.h @@ -49,7 +49,7 @@ static inline void pattern_set_bit(u32 x, u32 y, u32 pitch, char *pat) static inline void rotate_ud(const char *in, char *out, u32 width, u32 height) { int i, j; - int shift = width % 8; + int shift = (8 - (width % 8)) & 7; width = (width + 7) & ~7; @@ -85,7 +85,7 @@ static inline void rotate_cw(const char *in, char *out, u32 width, u32 height) static inline void rotate_ccw(const char *in, char *out, u32 width, u32 height) { int i, j, h = height, w = width; - int shift = width % 8; + int shift = (8 - (width % 8)) & 7; width = (width + 7) & ~7; height = (height + 7) & ~7;