diff --git a/arch/powerpc/include/asm/systbl.h b/arch/powerpc/include/asm/systbl.h
index f2b0b1b0c72a..5654ece02c0d 100644
--- a/arch/powerpc/include/asm/systbl.h
+++ b/arch/powerpc/include/asm/systbl.h
@@ -370,16 +370,16 @@ COMPAT_SYS(execveat)
 PPC64ONLY(switch_endian)
 SYSCALL_SPU(userfaultfd)
 SYSCALL_SPU(membarrier)
-SYSCALL(semop)
-SYSCALL(semget)
-COMPAT_SYS(semctl)
-COMPAT_SYS(semtimedop)
-COMPAT_SYS(msgsnd)
-COMPAT_SYS(msgrcv)
-SYSCALL(msgget)
-COMPAT_SYS(msgctl)
-COMPAT_SYS(shmat)
-SYSCALL(shmdt)
-SYSCALL(shmget)
-COMPAT_SYS(shmctl)
+SYSCALL(ni_syscall)
+SYSCALL(ni_syscall)
+SYSCALL(ni_syscall)
+SYSCALL(ni_syscall)
+SYSCALL(ni_syscall)
+SYSCALL(ni_syscall)
+SYSCALL(ni_syscall)
+SYSCALL(ni_syscall)
+SYSCALL(ni_syscall)
+SYSCALL(ni_syscall)
+SYSCALL(ni_syscall)
+SYSCALL(ni_syscall)
 SYSCALL(mlock2)
diff --git a/arch/powerpc/include/uapi/asm/unistd.h b/arch/powerpc/include/uapi/asm/unistd.h
index 1effea5193d6..12a05652377a 100644
--- a/arch/powerpc/include/uapi/asm/unistd.h
+++ b/arch/powerpc/include/uapi/asm/unistd.h
@@ -388,18 +388,6 @@
 #define __NR_switch_endian	363
 #define __NR_userfaultfd	364
 #define __NR_membarrier		365
-#define __NR_semop		366
-#define __NR_semget		367
-#define __NR_semctl		368
-#define __NR_semtimedop		369
-#define __NR_msgsnd		370
-#define __NR_msgrcv		371
-#define __NR_msgget		372
-#define __NR_msgctl		373
-#define __NR_shmat		374
-#define __NR_shmdt		375
-#define __NR_shmget		376
-#define __NR_shmctl		377
 #define __NR_mlock2		378
 
 #endif /* _UAPI_ASM_POWERPC_UNISTD_H_ */
diff --git a/arch/powerpc/platforms/powernv/opal-irqchip.c b/arch/powerpc/platforms/powernv/opal-irqchip.c
index 0a00e2aed393..e505223b4ec5 100644
--- a/arch/powerpc/platforms/powernv/opal-irqchip.c
+++ b/arch/powerpc/platforms/powernv/opal-irqchip.c
@@ -83,7 +83,19 @@ static void opal_event_unmask(struct irq_data *d)
 	set_bit(d->hwirq, &opal_event_irqchip.mask);
 
 	opal_poll_events(&events);
-	opal_handle_events(be64_to_cpu(events));
+	last_outstanding_events = be64_to_cpu(events);
+
+	/*
+	 * We can't just handle the events now with opal_handle_events().
+	 * If we did we would deadlock when opal_event_unmask() is called from
+	 * handle_level_irq() with the irq descriptor lock held, because
+	 * calling opal_handle_events() would call generic_handle_irq() and
+	 * then handle_level_irq() which would try to take the descriptor lock
+	 * again. Instead queue the events for later.
+	 */
+	if (last_outstanding_events & opal_event_irqchip.mask)
+		/* Need to retrigger the interrupt */
+		irq_work_queue(&opal_event_irq_work);
 }
 
 static int opal_event_set_type(struct irq_data *d, unsigned int flow_type)
diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c
index 4296d55e88f3..57cffb80bc36 100644
--- a/arch/powerpc/platforms/powernv/opal.c
+++ b/arch/powerpc/platforms/powernv/opal.c
@@ -278,7 +278,7 @@ static void opal_handle_message(void)
 
 	/* Sanity check */
 	if (type >= OPAL_MSG_TYPE_MAX) {
-		pr_warning("%s: Unknown message type: %u\n", __func__, type);
+		pr_warn_once("%s: Unknown message type: %u\n", __func__, type);
 		return;
 	}
 	opal_message_do_notify(type, (void *)&msg);