Adding debian version 6.1.76-1.debian/6.1.76-1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 95 insertions, 0 deletions

diff --git a/debian/patches-rt/0029-drm-i915-gt-Use-spin_lock_irq-instead-of-local_irq_d.patch b/debian/patches-rt/0029-drm-i915-gt-Use-spin_lock_irq-instead-of-local_irq_d.patch
new file mode 100644
index 000000000..d7696f54a
--- /dev/null
+++ b/debian/patches-rt/0029-drm-i915-gt-Use-spin_lock_irq-instead-of-local_irq_d.patch
@@ -0,0 +1,95 @@
+From 6ca6d59038e0a61a7bb4904310525b1df57a2867 Mon Sep 17 00:00:00 2001
+From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+Date: Wed, 8 Sep 2021 19:03:41 +0200
+Subject: [PATCH 29/62] drm/i915/gt: Use spin_lock_irq() instead of
+ local_irq_disable() + spin_lock()
+Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/6.1/older/patches-6.1.69-rt21.tar.xz
+
+execlists_dequeue() is invoked from a function which uses
+local_irq_disable() to disable interrupts so the spin_lock() behaves
+like spin_lock_irq().
+This breaks PREEMPT_RT because local_irq_disable() + spin_lock() is not
+the same as spin_lock_irq().
+
+execlists_dequeue_irq() and execlists_dequeue() has each one caller
+only. If intel_engine_cs::active::lock is acquired and released with the
+_irq suffix then it behaves almost as if execlists_dequeue() would be
+invoked with disabled interrupts. The difference is the last part of the
+function which is then invoked with enabled interrupts.
+I can't tell if this makes a difference. From looking at it, it might
+work to move the last unlock at the end of the function as I didn't find
+anything that would acquire the lock again.
+
+Reported-by: Clark Williams <williams@redhat.com>
+Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
+---
+ .../drm/i915/gt/intel_execlists_submission.c    | 17 +++++------------
+ 1 file changed, 5 insertions(+), 12 deletions(-)
+
+diff --git a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
+index f903ee1ce06e..f54059b63ea9 100644
+--- a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
++++ b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
+@@ -1302,7 +1302,7 @@ static void execlists_dequeue(struct intel_engine_cs *engine)
+ 	 * and context switches) submission.
+ 	 */
+ 
+-	spin_lock(&sched_engine->lock);
++	spin_lock_irq(&sched_engine->lock);
+ 
+ 	/*
+ 	 * If the queue is higher priority than the last
+@@ -1402,7 +1402,7 @@ static void execlists_dequeue(struct intel_engine_cs *engine)
+ 				 * Even if ELSP[1] is occupied and not worthy
+ 				 * of timeslices, our queue might be.
+ 				 */
+-				spin_unlock(&sched_engine->lock);
++				spin_unlock_irq(&sched_engine->lock);
+ 				return;
+ 			}
+ 		}
+@@ -1428,7 +1428,7 @@ static void execlists_dequeue(struct intel_engine_cs *engine)
+ 
+ 		if (last && !can_merge_rq(last, rq)) {
+ 			spin_unlock(&ve->base.sched_engine->lock);
+-			spin_unlock(&engine->sched_engine->lock);
++			spin_unlock_irq(&engine->sched_engine->lock);
+ 			return; /* leave this for another sibling */
+ 		}
+ 
+@@ -1590,7 +1590,7 @@ static void execlists_dequeue(struct intel_engine_cs *engine)
+ 	 */
+ 	sched_engine->queue_priority_hint = queue_prio(sched_engine);
+ 	i915_sched_engine_reset_on_empty(sched_engine);
+-	spin_unlock(&sched_engine->lock);
++	spin_unlock_irq(&sched_engine->lock);
+ 
+ 	/*
+ 	 * We can skip poking the HW if we ended up with exactly the same set
+@@ -1616,13 +1616,6 @@ static void execlists_dequeue(struct intel_engine_cs *engine)
+ 	}
+ }
+ 
+-static void execlists_dequeue_irq(struct intel_engine_cs *engine)
+-{
+-	local_irq_disable(); /* Suspend interrupts across request submission */
+-	execlists_dequeue(engine);
+-	local_irq_enable(); /* flush irq_work (e.g. breadcrumb enabling) */
+-}
+-
+ static void clear_ports(struct i915_request **ports, int count)
+ {
+ 	memset_p((void **)ports, NULL, count);
+@@ -2476,7 +2469,7 @@ static void execlists_submission_tasklet(struct tasklet_struct *t)
+ 	}
+ 
+ 	if (!engine->execlists.pending[0]) {
+-		execlists_dequeue_irq(engine);
++		execlists_dequeue(engine);
+ 		start_timeslice(engine);
+ 	}
+ 
+-- 
+2.43.0
+