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, 81 insertions, 0 deletions

diff --git a/debian/patches-rt/0013-rcutorture-Also-force-sched-priority-to-timersd-on-b.patch b/debian/patches-rt/0013-rcutorture-Also-force-sched-priority-to-timersd-on-b.patch
new file mode 100644
index 000000000..9e062b97c
--- /dev/null
+++ b/debian/patches-rt/0013-rcutorture-Also-force-sched-priority-to-timersd-on-b.patch
@@ -0,0 +1,81 @@
+From a10aa54ef224bbd46ca1777e4b9fe960360961cc Mon Sep 17 00:00:00 2001
+From: Frederic Weisbecker <frederic@kernel.org>
+Date: Tue, 5 Apr 2022 03:07:51 +0200
+Subject: [PATCH 13/62] rcutorture: Also force sched priority to timersd on
+ boosting test.
+Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/6.1/older/patches-6.1.69-rt21.tar.xz
+
+ksoftirqd is statically boosted to the priority level right above the
+one of rcu_torture_boost() so that timers, which torture readers rely on,
+get a chance to run while rcu_torture_boost() is polling.
+
+However timers processing got split from ksoftirqd into their own kthread
+(timersd) that isn't boosted. It has the same SCHED_FIFO low prio as
+rcu_torture_boost() and therefore timers can't preempt it and may
+starve.
+
+The issue can be triggered in practice on v5.17.1-rt17 using:
+
+	./kvm.sh --allcpus --configs TREE04 --duration 10m --kconfig "CONFIG_EXPERT=y CONFIG_PREEMPT_RT=y"
+
+Fix this with statically boosting timersd just like is done with
+ksoftirqd in commit
+   ea6d962e80b61 ("rcutorture: Judge RCU priority boosting on grace periods, not callbacks")
+
+Suggested-by: Mel Gorman <mgorman@suse.de>
+Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+Cc: Thomas Gleixner <tglx@linutronix.de>
+Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
+Link: https://lkml.kernel.org/r/20220405010752.1347437-1-frederic@kernel.org
+Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+---
+ include/linux/interrupt.h | 1 +
+ kernel/rcu/rcutorture.c   | 6 ++++++
+ kernel/softirq.c          | 2 +-
+ 3 files changed, 8 insertions(+), 1 deletion(-)
+
+diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
+index 0efba74a835c..f459b0f27c94 100644
+--- a/include/linux/interrupt.h
++++ b/include/linux/interrupt.h
+@@ -610,6 +610,7 @@ extern void raise_softirq_irqoff(unsigned int nr);
+ extern void raise_softirq(unsigned int nr);
+ 
+ #ifdef CONFIG_PREEMPT_RT
++DECLARE_PER_CPU(struct task_struct *, timersd);
+ extern void raise_timer_softirq(void);
+ extern void raise_hrtimer_softirq(void);
+ 
+diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
+index 503c2aa845a4..dcd8c0e44c00 100644
+--- a/kernel/rcu/rcutorture.c
++++ b/kernel/rcu/rcutorture.c
+@@ -2363,6 +2363,12 @@ static int rcutorture_booster_init(unsigned int cpu)
+ 		WARN_ON_ONCE(!t);
+ 		sp.sched_priority = 2;
+ 		sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
++#ifdef CONFIG_PREEMPT_RT
++		t = per_cpu(timersd, cpu);
++		WARN_ON_ONCE(!t);
++		sp.sched_priority = 2;
++		sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
++#endif
+ 	}
+ 
+ 	/* Don't allow time recalculation while creating a new task. */
+diff --git a/kernel/softirq.c b/kernel/softirq.c
+index ed6d7c41aa17..1892af494cdd 100644
+--- a/kernel/softirq.c
++++ b/kernel/softirq.c
+@@ -638,7 +638,7 @@ static inline void tick_irq_exit(void)
+ }
+ 
+ #ifdef CONFIG_PREEMPT_RT
+-static DEFINE_PER_CPU(struct task_struct *, timersd);
++DEFINE_PER_CPU(struct task_struct *, timersd);
+ static DEFINE_PER_CPU(unsigned long, pending_timer_softirq);
+ 
+ static unsigned int local_pending_timers(void)
+-- 
+2.43.0
+