From: James Simmons Currently when going from vgacon to fbcon the VT screenbuffer are often different sizes. In the case when they are different sizes a new VT screenbuffer is allocated and the contents are copied into the new buffer. Currently the amount copied from VGA text memory to the new screenbuf is the size of the framebuffer console. If the framebuffer console new VT screen buffer is greater than the VGA text memory size then we get some of the VGA BIOS contents as well. This patch will only allow you to copy up to the size of VGA text memory now. The rest is filled with erase characters. Initial patch by Jordan Crouse Signed-off-by: James Simmons Signed-off-by: Andrew Morton --- drivers/video/console/vgacon.c | 17 +++++++++++++---- 1 files changed, 13 insertions(+), 4 deletions(-) diff -puN drivers/video/console/vgacon.c~vga-to-fbcon-fix drivers/video/console/vgacon.c --- 25/drivers/video/console/vgacon.c~vga-to-fbcon-fix 2005-05-17 00:46:07.000000000 -0700 +++ 25-akpm/drivers/video/console/vgacon.c 2005-05-17 00:46:07.000000000 -0700 @@ -95,6 +95,7 @@ static unsigned long vgacon_uni_pagedir[ /* Description of the hardware situation */ static unsigned long vga_vram_base; /* Base of video memory */ static unsigned long vga_vram_end; /* End of video memory */ +static int vga_vram_size; /* Size of video memory */ static u16 vga_video_port_reg; /* Video register select port */ static u16 vga_video_port_val; /* Video register value port */ static unsigned int vga_video_num_columns; /* Number of text columns */ @@ -288,6 +289,7 @@ static const char __init *vgacon_startup vga_vram_base = VGA_MAP_MEM(vga_vram_base); vga_vram_end = VGA_MAP_MEM(vga_vram_end); + vga_vram_size = vga_vram_end - vga_vram_base; /* * Find out if there is a graphics card present. @@ -504,9 +506,13 @@ static int vgacon_switch(struct vc_data */ vga_video_num_columns = c->vc_cols; vga_video_num_lines = c->vc_rows; + + /* We can only copy out the size of the video buffer here, + * otherwise we get into VGA BIOS */ + if (!vga_is_gfx) scr_memcpyw((u16 *) c->vc_origin, (u16 *) c->vc_screenbuf, - c->vc_screenbuf_size); + c->vc_screenbuf_size > vga_vram_size ? vga_vram_size : c->vc_screenbuf_size); return 0; /* Redrawing not needed */ } @@ -961,7 +967,6 @@ static int vgacon_scrolldelta(struct vc_ if (!lines) /* Turn scrollback off */ c->vc_visible_origin = c->vc_origin; else { - int vram_size = vga_vram_end - vga_vram_base; int margin = c->vc_size_row * 4; int ul, we, p, st; @@ -971,7 +976,7 @@ static int vgacon_scrolldelta(struct vc_ we = vga_rolled_over + c->vc_size_row; } else { ul = 0; - we = vram_size; + we = vga_vram_size; } p = (c->vc_visible_origin - vga_vram_base - ul + we) % we + lines * c->vc_size_row; @@ -1012,9 +1017,13 @@ static void vgacon_save_screen(struct vc c->vc_x = ORIG_X; c->vc_y = ORIG_Y; } + + /* We can't copy in more then the size of the video buffer, + * or we'll be copying in VGA BIOS */ + if (!vga_is_gfx) scr_memcpyw((u16 *) c->vc_screenbuf, (u16 *) c->vc_origin, - c->vc_screenbuf_size); + c->vc_screenbuf_size > vga_vram_size ? vga_vram_size : c->vc_screenbuf_size); } static int vgacon_scroll(struct vc_data *c, int t, int b, int dir, _