8 files changed, 27 insertions, 9 deletions

diff --git a/drivers/char/vt.c b/drivers/char/vt.c
index 34bfb056d7a6..82f64ac21191 100644
--- a/drivers/char/vt.c
+++ b/drivers/char/vt.c
@@ -705,7 +705,10 @@ 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);
@@ -743,6 +746,7 @@ 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;
@@ -2506,7 +2510,7 @@ 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 */
@@ -3784,7 +3788,8 @@ 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) {
@@ -3793,7 +3798,7 @@ 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 54acd8b534df..a79525f434a8 100644
--- a/drivers/gpu/drm/i915/intel_fb.c
+++ b/drivers/gpu/drm/i915/intel_fb.c
@@ -130,7 +130,7 @@ 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 */
@@ -148,8 +148,6 @@ 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 2fb2444d2322..099f637264aa 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 dc1634bb0c11..dbf86962bdd1 100644
--- a/drivers/gpu/drm/radeon/radeon_fb.c
+++ b/drivers/gpu/drm/radeon/radeon_fb.c
@@ -224,7 +224,7 @@ static int radeonfb_create(struct radeon_fbdev *rfbdev,
 
         drm_fb_helper_fill_fix(info, fb->pitch, fb->depth);
 
-        info->flags = FBINFO_DEFAULT;
+        info->flags = FBINFO_DEFAULT | FBINFO_CAN_FORCE_OUTPUT;
         info->fbops = &radeonfb_ops;
 
         tmp = radeon_bo_gpu_offset(rbo) - rdev->mc.vram_start;
diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c
index 3b3f5749af92..26bf7cbfecc2 100644
--- a/drivers/video/console/fbcon.c
+++ b/drivers/video/console/fbcon.c
@@ -283,7 +283,8 @@ static inline int fbcon_is_inactive(struct vc_data *vc, struct fb_info *info)
         struct fbcon_ops *ops = info->fbcon_par;
 
         return (info->state != FBINFO_STATE_RUNNING ||
-                vc->vc_mode != KD_TEXT || ops->graphics);
+                vc->vc_mode != KD_TEXT || ops->graphics) &&
+                !vt_force_oops_output(vc);
 }
 
 static inline int get_color(struct vc_data *vc, struct fb_info *info,
@@ -1073,6 +1074,7 @@ static void fbcon_init(struct vc_data *vc, int init)
         if (p->userfont)
                 charcnt = FNTCHARCNT(p->fontdata);
 
+        vc->vc_panic_force_write = !!(info->flags & FBINFO_CAN_FORCE_OUTPUT);
         vc->vc_can_do_color = (fb_get_color_depth(&info->var, &info->fix)!=1);
         vc->vc_complement_mask = vc->vc_can_do_color ? 0x7700 : 0x0800;
         if (charcnt == 256) {
diff --git a/include/linux/console_struct.h b/include/linux/console_struct.h
index 38fe59dc89ae..d7d9acdccffb 100644
--- a/include/linux/console_struct.h
+++ b/include/linux/console_struct.h
@@ -105,6 +105,7 @@ struct vc_data {
         struct vc_data **vc_display_fg;         /* [!] Ptr to var holding fg console for this display */
         unsigned long   vc_uni_pagedir;
         unsigned long   *vc_uni_pagedir_loc;  /* [!] Location of uni_pagedir variable for this console */
+        bool vc_panic_force_write; /* when oops/panic this VC can accept forced output/blanking */
         /* additional information is in vt_kern.h */
 };
 
diff --git a/include/linux/fb.h b/include/linux/fb.h
index 0c5659c41b01..f0268deca658 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -825,6 +825,10 @@ struct fb_tile_ops {
  */
 #define FBINFO_BE_MATH  0x100000
 
+/* report to the VT layer that this fb driver can accept forced console
+   output like oopses */
+#define FBINFO_CAN_FORCE_OUTPUT     0x200000
+
 struct fb_info {
         int node;
         int flags;
diff --git a/include/linux/vt_kern.h b/include/linux/vt_kern.h
index 7f56db4a79f0..56cce345aa8d 100644
--- a/include/linux/vt_kern.h
+++ b/include/linux/vt_kern.h
@@ -100,6 +100,13 @@ extern int unbind_con_driver(const struct consw *csw, int first, int last,
                              int deflt);
 int vty_init(const struct file_operations *console_fops);
 
+static inline bool vt_force_oops_output(struct vc_data *vc)
+{
+        if (oops_in_progress && vc->vc_panic_force_write)
+                return true;
+        return false;
+}
+
 /*
  * vc_screen.c shares this temporary buffer with the console write code so that
  * we can easily avoid touching user space while holding the console spinlock.