diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
index 15d7c47fb7ca3..475b51f4321db 100644
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c
@@ -55,16 +55,7 @@ static struct uart_driver serial8250_reg;
 
 static unsigned int skip_txen_test; /* force skip of txen test at init time */
 
-/*
- * On -rt we can have a more delays, and legitimately
- * so - so don't drop work spuriously and spam the
- * syslog:
- */
-#ifdef CONFIG_PREEMPT_RT
-# define PASS_LIMIT	1000000
-#else
-# define PASS_LIMIT	512
-#endif
+#define PASS_LIMIT	512
 
 #include <asm/serial.h>
 /*
diff --git a/localversion-rt b/localversion-rt
index ad3da1bcab7e8..0efe7ba1930e1 100644
--- a/localversion-rt
+++ b/localversion-rt
@@ -1 +1 @@
--rt4
+-rt5
diff --git a/mm/slub.c b/mm/slub.c
index 15c194ff16e6e..9ec40d561b68c 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1655,7 +1655,7 @@ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)
 		enableirqs = true;
 
 #ifdef CONFIG_PREEMPT_RT
-	if (system_state > SYSTEM_BOOTING)
+	if (system_state > SYSTEM_BOOTING && system_state < SYSTEM_SUSPEND)
 		enableirqs = true;
 #endif
 	if (enableirqs)
@@ -2402,9 +2402,6 @@ static void flush_all(struct kmem_cache *s)
 	for_each_online_cpu(cpu) {
 		struct slub_free_list *f;
 
-		if (!has_cpu_slab(cpu, s))
-			continue;
-
 		f = &per_cpu(slub_free_list, cpu);
 		raw_spin_lock_irq(&f->lock);
 		list_splice_init(&f->list, &tofree);
@@ -2771,7 +2768,8 @@ static __always_inline void *slab_alloc_node(struct kmem_cache *s,
 	unsigned long tid;
 
 	if (IS_ENABLED(CONFIG_PREEMPT_RT) && IS_ENABLED(CONFIG_DEBUG_ATOMIC_SLEEP))
-		WARN_ON_ONCE(!preemptible() && system_state >= SYSTEM_SCHEDULING);
+		WARN_ON_ONCE(!preemptible() &&
+			     (system_state > SYSTEM_BOOTING && system_state < SYSTEM_SUSPEND));
 
 	s = slab_pre_alloc_hook(s, gfpflags);
 	if (!s)
@@ -3236,7 +3234,8 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size,
 	int i;
 
 	if (IS_ENABLED(CONFIG_PREEMPT_RT) && IS_ENABLED(CONFIG_DEBUG_ATOMIC_SLEEP))
-		WARN_ON_ONCE(!preemptible() && system_state >= SYSTEM_SCHEDULING);
+		WARN_ON_ONCE(!preemptible() &&
+			     (system_state > SYSTEM_BOOTING && system_state < SYSTEM_SUSPEND));
 
 	/* memcg and kmem_cache debug support */
 	s = slab_pre_alloc_hook(s, flags);
