diff --git a/arch/s390/include/asm/lowcore.h b/arch/s390/include/asm/lowcore.h
index 3c85c60f56ac..adf7f473ad8f 100644
--- a/arch/s390/include/asm/lowcore.h
+++ b/arch/s390/include/asm/lowcore.h
@@ -48,10 +48,15 @@ struct lowcore {
 	__u8	pad_0x00a4[0x00a8-0x00a4];	/* 0x00a4 */
 	__u64	trans_exc_code;			/* 0x00a8 */
 	__u64	monitor_code;			/* 0x00b0 */
-	__u16	subchannel_id;			/* 0x00b8 */
-	__u16	subchannel_nr;			/* 0x00ba */
-	__u32	io_int_parm;			/* 0x00bc */
-	__u32	io_int_word;			/* 0x00c0 */
+	union {
+		struct {
+			__u16	subchannel_id;	/* 0x00b8 */
+			__u16	subchannel_nr;	/* 0x00ba */
+			__u32	io_int_parm;	/* 0x00bc */
+			__u32	io_int_word;	/* 0x00c0 */
+		};
+		struct tpi_info	tpi_info;	/* 0x00b8 */
+	};
 	__u8	pad_0x00c4[0x00c8-0x00c4];	/* 0x00c4 */
 	__u32	stfl_fac_list;			/* 0x00c8 */
 	__u8	pad_0x00cc[0x00e8-0x00cc];	/* 0x00cc */
diff --git a/arch/s390/kernel/irq.c b/arch/s390/kernel/irq.c
index 169258012530..c0df4060d28d 100644
--- a/arch/s390/kernel/irq.c
+++ b/arch/s390/kernel/irq.c
@@ -146,8 +146,8 @@ void noinstr do_io_irq(struct pt_regs *regs)
 		account_idle_time_irq();
 
 	do {
-		memcpy(&regs->int_code, &S390_lowcore.subchannel_id, 12);
-		if (S390_lowcore.io_int_word & BIT(31))
+		regs->tpi_info = S390_lowcore.tpi_info;
+		if (S390_lowcore.tpi_info.adapter_IO)
 			do_irq_async(regs, THIN_INTERRUPT);
 		else
 			do_irq_async(regs, IO_INTERRUPT);
diff --git a/drivers/s390/cio/trace.h b/drivers/s390/cio/trace.h
index 4803139bce14..86993de25345 100644
--- a/drivers/s390/cio/trace.h
+++ b/drivers/s390/cio/trace.h
@@ -168,10 +168,8 @@ TRACE_EVENT(s390_cio_tpi,
 			memset(&__entry->tpi_info, 0, sizeof(struct tpi_info));
 		else if (addr)
 			__entry->tpi_info = *addr;
-		else {
-			memcpy(&__entry->tpi_info, &S390_lowcore.subchannel_id,
-			       sizeof(struct tpi_info));
-		}
+		else
+			__entry->tpi_info = S390_lowcore.tpi_info;
 		__entry->cssid = __entry->tpi_info.schid.cssid;
 		__entry->ssid = __entry->tpi_info.schid.ssid;
 		__entry->schno = __entry->tpi_info.schid.sch_no;