From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Thu, 10 Jul 2025 14:50:42 +0000 (+0200)
Subject: 5.15-stable patches
X-Git-Tag: v5.15.188~94
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=66cf073a30a1a119b02284b60511bb6a9b4f90e4;p=thirdparty%2Fkernel%2Fstable-queue.git

5.15-stable patches

added patches:
	drm-exynos-exynos7_drm_decon-add-vblank-check-in-irq-handling.patch
	series
---

diff --git a/queue-5.15/drm-exynos-exynos7_drm_decon-add-vblank-check-in-irq-handling.patch b/queue-5.15/drm-exynos-exynos7_drm_decon-add-vblank-check-in-irq-handling.patch
new file mode 100644
index 0000000000..6158cc2929
--- /dev/null
+++ b/queue-5.15/drm-exynos-exynos7_drm_decon-add-vblank-check-in-irq-handling.patch
@@ -0,0 +1,47 @@
+From b846350aa272de99bf6fecfa6b08e64ebfb13173 Mon Sep 17 00:00:00 2001
+From: Kaustabh Chakraborty <kauschluss@disroot.org>
+Date: Fri, 27 Jun 2025 00:50:30 +0530
+Subject: drm/exynos: exynos7_drm_decon: add vblank check in IRQ handling
+
+From: Kaustabh Chakraborty <kauschluss@disroot.org>
+
+commit b846350aa272de99bf6fecfa6b08e64ebfb13173 upstream.
+
+If there's support for another console device (such as a TTY serial),
+the kernel occasionally panics during boot. The panic message and a
+relevant snippet of the call stack is as follows:
+
+  Unable to handle kernel NULL pointer dereference at virtual address 000000000000000
+  Call trace:
+    drm_crtc_handle_vblank+0x10/0x30 (P)
+    decon_irq_handler+0x88/0xb4
+    [...]
+
+Otherwise, the panics don't happen. This indicates that it's some sort
+of race condition.
+
+Add a check to validate if the drm device can handle vblanks before
+calling drm_crtc_handle_vblank() to avoid this.
+
+Cc: stable@vger.kernel.org
+Fixes: 96976c3d9aff ("drm/exynos: Add DECON driver")
+Signed-off-by: Kaustabh Chakraborty <kauschluss@disroot.org>
+Signed-off-by: Inki Dae <inki.dae@samsung.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/gpu/drm/exynos/exynos7_drm_decon.c |    4 ++++
+ 1 file changed, 4 insertions(+)
+
+--- a/drivers/gpu/drm/exynos/exynos7_drm_decon.c
++++ b/drivers/gpu/drm/exynos/exynos7_drm_decon.c
+@@ -601,6 +601,10 @@ static irqreturn_t decon_irq_handler(int
+ 	if (!ctx->drm_dev)
+ 		goto out;
+ 
++	/* check if crtc and vblank have been initialized properly */
++	if (!drm_dev_has_vblank(ctx->drm_dev))
++		goto out;
++
+ 	if (!ctx->i80_if) {
+ 		drm_crtc_handle_vblank(&ctx->crtc->base);
+ 
diff --git a/queue-5.15/series b/queue-5.15/series
new file mode 100644
index 0000000000..d837b8c8be
--- /dev/null
+++ b/queue-5.15/series
@@ -0,0 +1 @@
+drm-exynos-exynos7_drm_decon-add-vblank-check-in-irq-handling.patch