1 files changed, 47 insertions, 0 deletions
diff --git a/debian/patches-rt/0252-drm-i915-disable-tracing-on-RT.patch b/debian/patches-rt/0252-drm-i915-disable-tracing-on-RT.patch
new file mode 100644
index 000000000..833c9d37f
--- /dev/null
+++ b/debian/patches-rt/0252-drm-i915-disable-tracing-on-RT.patch
@@ -0,0 +1,47 @@
+From 0e88cde8cbd40cc7e519bccaf1ba847de2d9bd02 Mon Sep 17 00:00:00 2001
+From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+Date: Thu, 6 Dec 2018 09:52:20 +0100
+Subject: [PATCH 252/323] drm/i915: disable tracing on -RT
+Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/5.10/older/patches-5.10.204-rt100.tar.xz
+
+Luca Abeni reported this:
+| BUG: scheduling while atomic: kworker/u8:2/15203/0x00000003
+| CPU: 1 PID: 15203 Comm: kworker/u8:2 Not tainted 4.19.1-rt3 #10
+| Call Trace:
+|  rt_spin_lock+0x3f/0x50
+|  gen6_read32+0x45/0x1d0 [i915]
+|  g4x_get_vblank_counter+0x36/0x40 [i915]
+|  trace_event_raw_event_i915_pipe_update_start+0x7d/0xf0 [i915]
+
+The tracing events use trace_i915_pipe_update_start() among other events
+use functions acquire spin locks. A few trace points use
+intel_get_crtc_scanline(), others use ->get_vblank_counter() wich also
+might acquire a sleeping lock.
+
+Based on this I don't see any other way than disable trace points on RT.
+
+Cc: stable-rt@vger.kernel.org
+Reported-by: Luca Abeni <lucabe72@gmail.com>
+Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+---
+ drivers/gpu/drm/i915/i915_trace.h | 4 ++++
+ 1 file changed, 4 insertions(+)
+
+diff --git a/drivers/gpu/drm/i915/i915_trace.h b/drivers/gpu/drm/i915/i915_trace.h
+index a4addcc64978..0ba5a0a0fd25 100644
+--- a/drivers/gpu/drm/i915/i915_trace.h
++++ b/drivers/gpu/drm/i915/i915_trace.h
+@@ -2,6 +2,10 @@
+ #if !defined(_I915_TRACE_H_) || defined(TRACE_HEADER_MULTI_READ)
+ #define _I915_TRACE_H_
+ 
++#ifdef CONFIG_PREEMPT_RT
++#define NOTRACE
++#endif
++
+ #include <linux/stringify.h>
+ #include <linux/types.h>
+ #include <linux/tracepoint.h>
+-- 
+2.43.0
+