linux-kernel - [PATCH v6 6/8] drm/i915/display: Flush the front buffer in panic handler

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250401125818.333033-7-jfalempe@redhat.com>
Date: Tue,  1 Apr 2025 14:51:12 +0200
From: Jocelyn Falempe <jfalempe@...hat.com>
To: Jani Nikula <jani.nikula@...ux.intel.com>,
	Rodrigo Vivi <rodrigo.vivi@...el.com>,
	Joonas Lahtinen <joonas.lahtinen@...ux.intel.com>,
	Tvrtko Ursulin <tursulin@...ulin.net>,
	David Airlie <airlied@...il.com>,
	Simona Vetter <simona@...ll.ch>,
	intel-gfx@...ts.freedesktop.org,
	intel-xe@...ts.freedesktop.org,
	dri-devel@...ts.freedesktop.org,
	linux-kernel@...r.kernel.org
Cc: Jocelyn Falempe <jfalempe@...hat.com>
Subject: [PATCH v6 6/8] drm/i915/display: Flush the front buffer in panic handler

On Lunar Lake, if the panic occurs when fbcon is active, the panic
screen is only partially visible on the screen. Adding this
intel_frontbuffer_flush() call solves the issue.
It's probably not safe to do that in the panic handler, but that's
still better than nothing.

Signed-off-by: Jocelyn Falempe <jfalempe@...hat.com>
---
 drivers/gpu/drm/i915/display/intel_atomic_plane.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_atomic_plane.c b/drivers/gpu/drm/i915/display/intel_atomic_plane.c
index eebf20fafaeb..5dc880b963fd 100644
--- a/drivers/gpu/drm/i915/display/intel_atomic_plane.c
+++ b/drivers/gpu/drm/i915/display/intel_atomic_plane.c
@@ -59,6 +59,7 @@
 #include "intel_fb.h"
 #include "intel_fb_pin.h"
 #include "intel_fbdev.h"
+#include "intel_frontbuffer.h"
 #include "skl_scaler.h"
 #include "skl_universal_plane.h"
 #include "skl_watermark.h"
@@ -1273,7 +1274,13 @@ static void intel_panic_flush(struct drm_plane *plane)
 
 	/* Don't disable tiling if it's the fbdev framebuffer.*/
 	if (to_intel_framebuffer(fb) == intel_fbdev_framebuffer(display->fbdev.fbdev)) {
+		struct intel_frontbuffer *front = to_intel_frontbuffer(fb);
+		struct drm_gem_object *obj = intel_fb_bo(fb);
+
+		intel_bo_flush_if_display(obj);
+		intel_frontbuffer_flush(front, ORIGIN_DIRTYFB);
 		return;
+	}
 
 	if (fb->modifier && iplane->disable_tiling)
 		iplane->disable_tiling(iplane);
-- 
2.49.0