From: Jesse Barnes
Jesse's initial patch commit said:
"At panic time (i.e. when oops_in_progress is set) we should try a bit
harder to update the screen and make sure output gets to the VT, since
some drivers are capable of flipping back to it.
So make sure we try to unblank and update the display if called from a
panic context."
I've enhanced this to add a flag to the vc that console layer can set
to indicate they want this behaviour to occur. This also adds support
to fbcon for that flag and adds an fb flag for drivers to indicate
they want to use the support. It enables this for KMS drivers.
Signed-off-by: Dave Airlie
---
drivers/char/vt.c | 13 +
drivers/gpu/drm/i915/intel_fb.c |4 +---
drivers/gpu/drm/nouveau/nouveau_fbcon.c |1 +
drivers/gpu/drm/radeon/radeon_fb.c |2 +-
drivers/video/console/fbcon.c |4 +++-
include/linux/console_struct.h |1 +
include/linux/fb.h |4
include/linux/vt_kern.h |7 +++
8 files changed, 27 insertions(+), 9 deletions(-)
diff --git a/drivers/char/vt.c b/drivers/char/vt.c
index 7cdb6ee..6e04c9e 100644
--- a/drivers/char/vt.c
+++ b/drivers/char/vt.c
@@ -698,7 +698,10 @@ void redraw_screen(struct vc_data *vc, int is_switch)
update_attr(vc);
clear_buffer_attributes(vc);
}
- if (update && vc->vc_mode != KD_GRAPHICS)
+
+ /* Forcibly update if we're panicing */
+ if ((update && vc->vc_mode != KD_GRAPHICS) ||
+ vt_force_oops_output(vc))
do_update_region(vc, vc->vc_origin,
vc->vc_screenbuf_size / 2);
}
set_cursor(vc);
@@ -736,6 +739,7 @@ static void visual_init(struct vc_data *vc, int num, int
init)
vc->vc_hi_font_mask = 0;
vc->vc_complement_mask = 0;
vc->vc_can_do_color = 0;
+ vc->vc_panic_force_write = false;
vc->vc_sw->con_init(vc, init);
if (!vc->vc_complement_mask)
vc->vc_complement_mask = vc->vc_can_do_color ? 0x7700 : 0x0800;
@@ -2498,7 +2502,7 @@ static void vt_console_print(struct console *co, const
char *b, unsigned count)
goto quit;
}
- if (vc->vc_mode != KD_TEXT)
+ if (vc->vc_mode != KD_TEXT && !vt_force_oops_output(vc))
goto quit;
/* undraw cursor first */
@@ -3703,7 +3707,8 @@ void do_unblank_screen(int leaving_gfx)
return;
}
vc = vc_cons[fg_console].d;
- if (vc->vc_mode != KD_TEXT)
+ /* Try to unblank in oops case too */
+ if (vc->vc_mode != KD_TEXT && !vt_force_oops_output(vc))
return; /* but leave console_blanked != 0 */
if (blankinterval) {
@@ -3712,7 +3717,7 @@ void do_unblank_screen(int leaving_gfx)
}
console_blanked = 0;
- if (vc->vc_sw->con_blank(vc, 0, leaving_gfx))
+ if (vc->vc_sw->con_blank(vc, 0, leaving_gfx) ||
vt_force_oops_output(vc))
/* Low-level driver cannot restore -> do it ourselves */
update_screen(vc);
if (console_blank_hook)
diff --git a/drivers/gpu/drm/i915/intel_fb.c b/drivers/gpu/drm/i915/intel_fb.c
index c3c5052..bd5d87a 100644
--- a/drivers/gpu/drm/i915/intel_fb.c
+++ b/drivers/gpu/drm/i915/intel_fb.c
@@ -128,7 +128,7 @@ static int intelfb_create(struct intel_fbdev *ifbdev,
strcpy(info->fix.id, "inteldrmfb");
- info->flags = FBINFO_DEFAULT;
+ info->flags = FBINFO_DEFAULT | FBINFO_CAN_FORCE_OUTPUT;
info->fbops = &intelfb_ops;
/* setup aperture base/size for vesafb takeover */
@@ -146,8 +146,6 @@ static int intelfb_create(struct intel_fbdev *ifbdev,
info->fix.smem_start = dev->mode_config.fb_base + obj_priv->gtt_offset;
info->fix.smem_len = size;
- info->flags = FBINFO_DEFAULT;
-
info->screen_base = ioremap_wc(dev->agp->base + obj_priv->gtt_offset,
size);
if (!info->screen_base) {
diff --git a/drivers/gpu/drm/nouveau/nouveau_fbcon.c
b/drivers/gpu/drm/nouveau/nouveau_fbcon.c
index c9a4a0d..9b2d3b7 100644
--- a/drivers/gpu/drm/nouveau/nouveau_fbcon.c
+++ b/drivers/gpu/drm/nouveau/nouveau_fbcon.c
@@ -250,6 +250,7 @@ nouveau_fbcon_create(struct nouveau_fbdev *nfbdev,
info->flags = FBINFO_DEFAULT | FBINFO_HWACCEL_COPYAREA |
FBINFO_HWACCEL_FILLRECT |
FBINFO_HWACCEL_IMAGEBLIT;
+ info->flags |= FBINFO_CAN_FORCE_OUTPUT;
info->fbops = &nouveau_fbcon_ops;
info->fix.smem_start = dev->mode_config.fb_base + nvbo->bo.offset -
dev_priv->vm_vram_base;
diff --git a/drivers/gpu/drm/radeon/radeon_fb.c
b/drivers/gpu/drm/radeon/radeon_fb.c
index dc1634b..dbf8696 100644
--- a/drivers/gpu/drm/radeon/radeon_fb.c
+++ b/drivers/gpu/drm/radeon
