3 files changed, 18 insertions, 11 deletions
diff --git a/drivers/video/console/Kconfig b/drivers/video/console/Kconfig
index bc31db6ef7d2..12f54480f57f 100644
--- a/drivers/video/console/Kconfig
+++ b/drivers/video/console/Kconfig
@@ -24,7 +24,7 @@ config VGA_CONSOLE
 	  Say Y.
 
 config MDA_CONSOLE
-	depends on !M68K && !PARISC && ISA
+	depends on VGA_CONSOLE && ISA
 	tristate "MDA text console (dual-headed)"
 	help
 	  Say Y here if you have an old MDA or monochrome Hercules graphics
@@ -47,12 +47,11 @@ config SGI_NEWPORT_CONSOLE
 	  card of your Indy.  Most people say Y here.
 
 config DUMMY_CONSOLE
-	bool
-	default y
+	def_bool VT || VGA_CONSOLE || FRAMEBUFFER_CONSOLE
 
 config DUMMY_CONSOLE_COLUMNS
 	int "Initial number of console screen columns"
-	depends on DUMMY_CONSOLE && !ARCH_FOOTBRIDGE
+	depends on DUMMY_CONSOLE && !(ARCH_FOOTBRIDGE && VGA_CONSOLE)
 	default 160 if PARISC
 	default 80
 	help
@@ -62,7 +61,7 @@ config DUMMY_CONSOLE_COLUMNS
 
 config DUMMY_CONSOLE_ROWS
 	int "Initial number of console screen rows"
-	depends on DUMMY_CONSOLE && !ARCH_FOOTBRIDGE
+	depends on DUMMY_CONSOLE && !(ARCH_FOOTBRIDGE && VGA_CONSOLE)
 	default 64 if PARISC
 	default 30 if ARM
 	default 25
diff --git a/drivers/video/console/dummycon.c b/drivers/video/console/dummycon.c
index 139049368fdc..7d02470f19b9 100644
--- a/drivers/video/console/dummycon.c
+++ b/drivers/video/console/dummycon.c
@@ -85,6 +85,15 @@ static bool dummycon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
 	/* Redraw, so that we get putc(s) for output done while blanked */
 	return true;
 }
+
+static bool dummycon_switch(struct vc_data *vc)
+{
+	/*
+	 * Redraw, so that we get putc(s) for output done while switched
+	 * away. Informs deferred consoles to take over the display.
+	 */
+	return true;
+}
 #else
 static void dummycon_putc(struct vc_data *vc, u16 c, unsigned int y,
 			  unsigned int x) { }
@@ -95,6 +104,10 @@ static bool dummycon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
 {
 	return false;
 }
+static bool dummycon_switch(struct vc_data *vc)
+{
+	return false;
+}
 #endif
 
 static const char *dummycon_startup(void)
@@ -124,11 +137,6 @@ static bool dummycon_scroll(struct vc_data *vc, unsigned int top,
 	return false;
 }
 
-static bool dummycon_switch(struct vc_data *vc)
-{
-	return false;
-}
-
 /*
  *  The console `switch' structure for the dummy console
  *
diff --git a/drivers/video/console/vgacon.c b/drivers/video/console/vgacon.c
index 37bd18730fe0..f9cdbf8c53e3 100644
--- a/drivers/video/console/vgacon.c
+++ b/drivers/video/console/vgacon.c
@@ -1168,7 +1168,7 @@ static bool vgacon_scroll(struct vc_data *c, unsigned int t, unsigned int b,
 				     c->vc_screenbuf_size - delta);
 			c->vc_origin = vga_vram_end - c->vc_screenbuf_size;
 			vga_rolled_over = 0;
-		} else
+		} else if (oldo - delta >= (unsigned long)c->vc_screenbuf)
 			c->vc_origin -= delta;
 		c->vc_scr_end = c->vc_origin + c->vc_screenbuf_size;
 		scr_memsetw((u16 *) (c->vc_origin), c->vc_video_erase_char,