Adding debian version 6.6.15-2.debian/6.6.15-2

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

1 files changed, 177 insertions, 0 deletions

diff --git a/debian/patches-rt/0005-locking-rtmutex-Use-rt_mutex-specific-scheduler-help.patch b/debian/patches-rt/0005-locking-rtmutex-Use-rt_mutex-specific-scheduler-help.patch
new file mode 100644
index 0000000000..d84497e5fd
--- /dev/null
+++ b/debian/patches-rt/0005-locking-rtmutex-Use-rt_mutex-specific-scheduler-help.patch
@@ -0,0 +1,177 @@
+From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+Date: Fri, 8 Sep 2023 18:22:52 +0200
+Subject: [PATCH 5/7] locking/rtmutex: Use rt_mutex specific scheduler helpers
+Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/6.6/older/patches-6.6.7-rt18.tar.xz
+
+Have rt_mutex use the rt_mutex specific scheduler helpers to avoid
+recursion vs rtlock on the PI state.
+
+[[ peterz: adapted to new names ]]
+
+Reported-by: Crystal Wood <swood@redhat.com>
+Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
+Link: https://lkml.kernel.org/r/20230908162254.999499-6-bigeasy@linutronix.de
+---
+ kernel/futex/pi.c            |   11 +++++++++++
+ kernel/locking/rtmutex.c     |   14 ++++++++++++--
+ kernel/locking/rwbase_rt.c   |    6 ++++++
+ kernel/locking/rwsem.c       |    8 +++++++-
+ kernel/locking/spinlock_rt.c |    4 ++++
+ 5 files changed, 40 insertions(+), 3 deletions(-)
+
+--- a/kernel/futex/pi.c
++++ b/kernel/futex/pi.c
+@@ -1,6 +1,7 @@
+ // SPDX-License-Identifier: GPL-2.0-or-later
+ 
+ #include <linux/slab.h>
++#include <linux/sched/rt.h>
+ #include <linux/sched/task.h>
+ 
+ #include "futex.h"
+@@ -1002,6 +1003,12 @@ int futex_lock_pi(u32 __user *uaddr, uns
+ 		goto no_block;
+ 	}
+ 
++	/*
++	 * Must be done before we enqueue the waiter, here is unfortunately
++	 * under the hb lock, but that *should* work because it does nothing.
++	 */
++	rt_mutex_pre_schedule();
++
+ 	rt_mutex_init_waiter(&rt_waiter);
+ 
+ 	/*
+@@ -1052,6 +1059,10 @@ int futex_lock_pi(u32 __user *uaddr, uns
+ 	if (ret && !rt_mutex_cleanup_proxy_lock(&q.pi_state->pi_mutex, &rt_waiter))
+ 		ret = 0;
+ 
++	/*
++	 * Waiter is unqueued.
++	 */
++	rt_mutex_post_schedule();
+ no_block:
+ 	/*
+ 	 * Fixup the pi_state owner and possibly acquire the lock if we
+--- a/kernel/locking/rtmutex.c
++++ b/kernel/locking/rtmutex.c
+@@ -1632,7 +1632,7 @@ static int __sched rt_mutex_slowlock_blo
+ 		raw_spin_unlock_irq(&lock->wait_lock);
+ 
+ 		if (!owner || !rtmutex_spin_on_owner(lock, waiter, owner))
+-			schedule();
++			rt_mutex_schedule();
+ 
+ 		raw_spin_lock_irq(&lock->wait_lock);
+ 		set_current_state(state);
+@@ -1661,7 +1661,7 @@ static void __sched rt_mutex_handle_dead
+ 	WARN(1, "rtmutex deadlock detected\n");
+ 	while (1) {
+ 		set_current_state(TASK_INTERRUPTIBLE);
+-		schedule();
++		rt_mutex_schedule();
+ 	}
+ }
+ 
+@@ -1757,6 +1757,15 @@ static int __sched rt_mutex_slowlock(str
+ 	int ret;
+ 
+ 	/*
++	 * Do all pre-schedule work here, before we queue a waiter and invoke
++	 * PI -- any such work that trips on rtlock (PREEMPT_RT spinlock) would
++	 * otherwise recurse back into task_blocks_on_rt_mutex() through
++	 * rtlock_slowlock() and will then enqueue a second waiter for this
++	 * same task and things get really confusing real fast.
++	 */
++	rt_mutex_pre_schedule();
++
++	/*
+ 	 * Technically we could use raw_spin_[un]lock_irq() here, but this can
+ 	 * be called in early boot if the cmpxchg() fast path is disabled
+ 	 * (debug, no architecture support). In this case we will acquire the
+@@ -1767,6 +1776,7 @@ static int __sched rt_mutex_slowlock(str
+ 	raw_spin_lock_irqsave(&lock->wait_lock, flags);
+ 	ret = __rt_mutex_slowlock_locked(lock, ww_ctx, state);
+ 	raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
++	rt_mutex_post_schedule();
+ 
+ 	return ret;
+ }
+--- a/kernel/locking/rwbase_rt.c
++++ b/kernel/locking/rwbase_rt.c
+@@ -71,6 +71,7 @@ static int __sched __rwbase_read_lock(st
+ 	struct rt_mutex_base *rtm = &rwb->rtmutex;
+ 	int ret;
+ 
++	rwbase_pre_schedule();
+ 	raw_spin_lock_irq(&rtm->wait_lock);
+ 
+ 	/*
+@@ -125,6 +126,7 @@ static int __sched __rwbase_read_lock(st
+ 		rwbase_rtmutex_unlock(rtm);
+ 
+ 	trace_contention_end(rwb, ret);
++	rwbase_post_schedule();
+ 	return ret;
+ }
+ 
+@@ -237,6 +239,8 @@ static int __sched rwbase_write_lock(str
+ 	/* Force readers into slow path */
+ 	atomic_sub(READER_BIAS, &rwb->readers);
+ 
++	rwbase_pre_schedule();
++
+ 	raw_spin_lock_irqsave(&rtm->wait_lock, flags);
+ 	if (__rwbase_write_trylock(rwb))
+ 		goto out_unlock;
+@@ -248,6 +252,7 @@ static int __sched rwbase_write_lock(str
+ 		if (rwbase_signal_pending_state(state, current)) {
+ 			rwbase_restore_current_state();
+ 			__rwbase_write_unlock(rwb, 0, flags);
++			rwbase_post_schedule();
+ 			trace_contention_end(rwb, -EINTR);
+ 			return -EINTR;
+ 		}
+@@ -266,6 +271,7 @@ static int __sched rwbase_write_lock(str
+ 
+ out_unlock:
+ 	raw_spin_unlock_irqrestore(&rtm->wait_lock, flags);
++	rwbase_post_schedule();
+ 	return 0;
+ }
+ 
+--- a/kernel/locking/rwsem.c
++++ b/kernel/locking/rwsem.c
+@@ -1427,8 +1427,14 @@ static inline void __downgrade_write(str
+ #define rwbase_signal_pending_state(state, current)	\
+ 	signal_pending_state(state, current)
+ 
++#define rwbase_pre_schedule()				\
++	rt_mutex_pre_schedule()
++
+ #define rwbase_schedule()				\
+-	schedule()
++	rt_mutex_schedule()
++
++#define rwbase_post_schedule()				\
++	rt_mutex_post_schedule()
+ 
+ #include "rwbase_rt.c"
+ 
+--- a/kernel/locking/spinlock_rt.c
++++ b/kernel/locking/spinlock_rt.c
+@@ -184,9 +184,13 @@ static __always_inline int  rwbase_rtmut
+ 
+ #define rwbase_signal_pending_state(state, current)	(0)
+ 
++#define rwbase_pre_schedule()
++
+ #define rwbase_schedule()				\
+ 	schedule_rtlock()
+ 
++#define rwbase_post_schedule()
++
+ #include "rwbase_rt.c"
+ /*
+  * The common functions which get wrapped into the rwlock API.