Revert "vt: fix background color on line feed"

This reverts commit c9e587abfdec2c2aaa55fab83bcb4972e2f84f9b, and the
subsequent commits that fixed it up:

 - afa9b649 "fbcon: prevent cursor disappearance after switching to 512
   character font"

 - d850a2fa "vt/fbcon: fix background color on line feed"

 - 7fe3915a "vt/fbcon: update scrl_erase_char after 256/512-glyph font
   switch"

by request of Alan Cox. Quoth Alan:
  "Unfortunately it's wrong and its been causing breakages because
   various apps like ncurses expect our previous (and correct)
   behaviour."

Alexander sent out a similar patch.

Requested-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Tested-by: Jan Engelhardt <jengelh@medozas.de>
Cc: Alexander V. Lukyanov <lav@netis.ru>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

5 files changed, 17 insertions, 37 deletions

diff --git a/drivers/char/vt.c b/drivers/char/vt.c
index 57029fefd64a..a0f7ffb68087 100644
--- a/drivers/char/vt.c
+++ b/drivers/char/vt.c
@@ -301,7 +301,7 @@ static void scrup(struct vc_data *vc, unsigned int t, unsigned int b, int nr)
         d = (unsigned short *)(vc->vc_origin + vc->vc_size_row * t);
         s = (unsigned short *)(vc->vc_origin + vc->vc_size_row * (t + nr));
         scr_memmovew(d, s, (b - t - nr) * vc->vc_size_row);
-        scr_memsetw(d + (b - t - nr) * vc->vc_cols, vc->vc_scrl_erase_char,
+        scr_memsetw(d + (b - t - nr) * vc->vc_cols, vc->vc_video_erase_char,
                     vc->vc_size_row * nr);
 }
 
@@ -319,7 +319,7 @@ static void scrdown(struct vc_data *vc, unsigned int t, unsigned int b, int nr)
         s = (unsigned short *)(vc->vc_origin + vc->vc_size_row * t);
         step = vc->vc_cols * nr;
         scr_memmovew(s + step, s, (b - t - nr) * vc->vc_size_row);
-        scr_memsetw(s, vc->vc_scrl_erase_char, 2 * step);
+        scr_memsetw(s, vc->vc_video_erase_char, 2 * step);
 }
 
 static void do_update_region(struct vc_data *vc, unsigned long start, int count)
@@ -434,7 +434,6 @@ static void update_attr(struct vc_data *vc)
                       vc->vc_blink, vc->vc_underline,
                       vc->vc_reverse ^ vc->vc_decscnm, vc->vc_italic);
         vc->vc_video_erase_char = (build_attr(vc, vc->vc_color, 1, vc->vc_blink, 0, vc->vc_decscnm, 0) << 8) | ' ';
-        vc->vc_scrl_erase_char = (build_attr(vc, vc->vc_def_color, 1, false, false, vc->vc_decscnm, false) << 8) | ' ';
 }
 
 /* Note: inverting the screen twice should revert to the original state */
diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c
index 9cbff84b787d..da91bb16da8a 100644
--- a/drivers/video/console/fbcon.c
+++ b/drivers/video/console/fbcon.c
@@ -1855,8 +1855,6 @@ static int fbcon_scroll(struct vc_data *vc, int t, int b, int dir,
         struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
         struct display *p = &fb_display[vc->vc_num];
         int scroll_partial = info->flags & FBINFO_PARTIAL_PAN_OK;
-        unsigned short saved_ec;
-        int ret;
 
         if (fbcon_is_inactive(vc, info))
                 return -EINVAL;
@@ -1869,11 +1867,6 @@ static int fbcon_scroll(struct vc_data *vc, int t, int b, int dir,
          *           whole screen (prevents flicker).
          */
 
-        saved_ec = vc->vc_video_erase_char;
-        vc->vc_video_erase_char = vc->vc_scrl_erase_char;
-
-        ret = 0;
-
         switch (dir) {
         case SM_UP:
                 if (count > vc->vc_rows)        /* Maximum realistic size */
@@ -1890,9 +1883,9 @@ static int fbcon_scroll(struct vc_data *vc, int t, int b, int dir,
                         scr_memsetw((unsigned short *) (vc->vc_origin +
                                                         vc->vc_size_row *
                                                         (b - count)),
-                                    vc->vc_scrl_erase_char,
+                                    vc->vc_video_erase_char,
                                     vc->vc_size_row * count);
-                        ret = 1;
+                        return 1;
                         break;
 
                 case SCROLL_WRAP_MOVE:
@@ -1962,10 +1955,9 @@ static int fbcon_scroll(struct vc_data *vc, int t, int b, int dir,
                         scr_memsetw((unsigned short *) (vc->vc_origin +
                                                         vc->vc_size_row *
                                                         (b - count)),
-                                    vc->vc_scrl_erase_char,
+                                    vc->vc_video_erase_char,
                                     vc->vc_size_row * count);
-                        ret = 1;
-                        break;
+                        return 1;
                 }
                 break;
 
@@ -1982,9 +1974,9 @@ static int fbcon_scroll(struct vc_data *vc, int t, int b, int dir,
                         scr_memsetw((unsigned short *) (vc->vc_origin +
                                                         vc->vc_size_row *
                                                         t),
-                                    vc->vc_scrl_erase_char,
+                                    vc->vc_video_erase_char,
                                     vc->vc_size_row * count);
-                        ret = 1;
+                        return 1;
                         break;
 
                 case SCROLL_WRAP_MOVE:
@@ -2052,15 +2044,12 @@ static int fbcon_scroll(struct vc_data *vc, int t, int b, int dir,
                         scr_memsetw((unsigned short *) (vc->vc_origin +
                                                         vc->vc_size_row *
                                                         t),
-                                    vc->vc_scrl_erase_char,
+                                    vc->vc_video_erase_char,
                                     vc->vc_size_row * count);
-                        ret = 1;
-                        break;
+                        return 1;
                 }
-                break;
         }
-        vc->vc_video_erase_char = saved_ec;
-        return ret;
+        return 0;
 }
 
 
@@ -2522,9 +2511,6 @@ static int fbcon_do_set_font(struct vc_data *vc, int w, int h,
                         c = vc->vc_video_erase_char;
                         vc->vc_video_erase_char =
                             ((c & 0xfe00) >> 1) | (c & 0xff);
-                        c = vc->vc_scrl_erase_char;
-                        vc->vc_scrl_erase_char =
-                            ((c & 0xFE00) >> 1) | (c & 0xFF);
                         vc->vc_attr >>= 1;
                 }
         } else if (!vc->vc_hi_font_mask && cnt == 512) {
@@ -2555,14 +2541,9 @@ static int fbcon_do_set_font(struct vc_data *vc, int w, int h,
                         if (vc->vc_can_do_color) {
                                 vc->vc_video_erase_char =
                                     ((c & 0xff00) << 1) | (c & 0xff);
-                                c = vc->vc_scrl_erase_char;
-                                vc->vc_scrl_erase_char =
-                                    ((c & 0xFF00) << 1) | (c & 0xFF);
                                 vc->vc_attr <<= 1;
-                        } else {
+                        } else
                                 vc->vc_video_erase_char = c & ~0x100;
-                                vc->vc_scrl_erase_char = c & ~0x100;
-                        }
                 }
 
         }
diff --git a/drivers/video/console/mdacon.c b/drivers/video/console/mdacon.c
index 9901064199bd..dd3eaaad4441 100644
--- a/drivers/video/console/mdacon.c
+++ b/drivers/video/console/mdacon.c
@@ -533,7 +533,7 @@ static void mdacon_cursor(struct vc_data *c, int mode)
 
 static int mdacon_scroll(struct vc_data *c, int t, int b, int dir, int lines)
 {
-        u16 eattr = mda_convert_attr(c->vc_scrl_erase_char);
+        u16 eattr = mda_convert_attr(c->vc_video_erase_char);
 
         if (!lines)
                 return 0;
diff --git a/drivers/video/console/sticon.c b/drivers/video/console/sticon.c
index 4055dbdd1b42..491c1c1baf4c 100644
--- a/drivers/video/console/sticon.c
+++ b/drivers/video/console/sticon.c
@@ -170,12 +170,12 @@ static int sticon_scroll(struct vc_data *conp, int t, int b, int dir, int count)
     switch (dir) {
     case SM_UP:
         sti_bmove(sti, t + count, 0, t, 0, b - t - count, conp->vc_cols);
-        sti_clear(sti, b - count, 0, count, conp->vc_cols, conp->vc_scrl_erase_char);
+        sti_clear(sti, b - count, 0, count, conp->vc_cols, conp->vc_video_erase_char);
         break;
 
     case SM_DOWN:
         sti_bmove(sti, t, 0, t + count, 0, b - t - count, conp->vc_cols);
-        sti_clear(sti, t, 0, count, conp->vc_cols, conp->vc_scrl_erase_char);
+        sti_clear(sti, t, 0, count, conp->vc_cols, conp->vc_video_erase_char);
         break;
     }
 
diff --git a/drivers/video/console/vgacon.c b/drivers/video/console/vgacon.c
index bd1f57b259d9..6df29a62d720 100644
--- a/drivers/video/console/vgacon.c
+++ b/drivers/video/console/vgacon.c
@@ -1350,7 +1350,7 @@ static int vgacon_scroll(struct vc_data *c, int t, int b, int dir,
                 } else
                         c->vc_origin += delta;
                 scr_memsetw((u16 *) (c->vc_origin + c->vc_screenbuf_size -
-                                     delta), c->vc_scrl_erase_char,
+                                     delta), c->vc_video_erase_char,
                             delta);
         } else {
                 if (oldo - delta < vga_vram_base) {
@@ -1363,7 +1363,7 @@ static int vgacon_scroll(struct vc_data *c, int t, int b, int dir,
                 } else
                         c->vc_origin -= delta;
                 c->vc_scr_end = c->vc_origin + c->vc_screenbuf_size;
-                scr_memsetw((u16 *) (c->vc_origin), c->vc_scrl_erase_char,
+                scr_memsetw((u16 *) (c->vc_origin), c->vc_video_erase_char,
                             delta);
         }
         c->vc_scr_end = c->vc_origin + c->vc_screenbuf_size;