diff --git a/src/include/sof/ipc/msg.h b/src/include/sof/ipc/msg.h
index 20dfaf6eb519..7c36f323c232 100644
--- a/src/include/sof/ipc/msg.h
+++ b/src/include/sof/ipc/msg.h
@@ -34,8 +34,7 @@ struct ipc_msg {
 	uint32_t header;	/* specific to platform */
 	uint32_t extension;	/* extension specific to platform */
 	uint32_t tx_size;	/* payload size in bytes */
-	void *tx_data;		/* pointer to payload data */
-	bool is_shared;		/* the message is shared cross-core */
+	void *tx_data;		/* pointer to payload data, must be in a non-cached memory */
 	struct list_item list;
 };
 
diff --git a/src/ipc/ipc-common.c b/src/ipc/ipc-common.c
index e9de1efdd2a0..7b88717049ec 100644
--- a/src/ipc/ipc-common.c
+++ b/src/ipc/ipc-common.c
@@ -216,15 +216,6 @@ void ipc_msg_send(struct ipc_msg *msg, void *data, bool high_priority)
 	    msg->tx_data != data) {
 		ret = memcpy_s(msg->tx_data, msg->tx_size, data, msg->tx_size);
 		assert(!ret);
-		if (!cpu_is_primary(cpu_get_id())) {
-			/* Write back data to memory to maintain coherence between cores.
-			 * The response was prepared on a secondary core but will be sent
-			 * to the host from the primary core.
-			 */
-			dcache_writeback_region((__sparse_force void __sparse_cache *)msg->tx_data,
-						msg->tx_size);
-			msg->is_shared = true;
-		}
 	}
 
 	/*
diff --git a/src/ipc/ipc4/handler.c b/src/ipc/ipc4/handler.c
index 6645d6fd08e5..ad6cf8bd6db4 100644
--- a/src/ipc/ipc4/handler.c
+++ b/src/ipc/ipc4/handler.c
@@ -72,9 +72,9 @@ struct ipc4_msg_data {
 static struct ipc4_msg_data msg_data;
 
 /* fw sends a fw ipc message to send the status of the last host ipc message */
-static struct ipc_msg msg_reply = {0, 0, 0, 0, false, LIST_INIT(msg_reply.list)};
+static struct ipc_msg msg_reply = {0, 0, 0, 0, LIST_INIT(msg_reply.list)};
 
-static struct ipc_msg msg_notify = {0, 0, 0, 0, false, LIST_INIT(msg_notify.list)};
+static struct ipc_msg msg_notify = {0, 0, 0, 0, LIST_INIT(msg_notify.list)};
 
 #if CONFIG_LIBRARY
 static inline struct ipc4_message_request *ipc4_get_message_request(void)
@@ -778,29 +778,14 @@ static int ipc4_process_ipcgtw_cmd(struct ipc4_message_request *ipc4)
 	uint32_t reply_size = 0;
 	int err;
 
-	/* NOTE: reply implementation is messy! First, reply payload is copied
-	 * to ipc->comp_data buffer. Then, new buffer is allocated and assigned
-	 * to msg_reply.tx_data. ipc_msg_send() copies payload from ipc->comp_data
-	 * to msg_reply.tx_data. Then, ipc_prepare_to_send() copies payload from
-	 * msg_reply.tx_data to memory window and frees msg_reply.tx_data. That is
-	 * quite weird: seems one extra copying can be eliminated.
-	 */
-
 	err = copier_ipcgtw_process((const struct ipc4_ipcgtw_cmd *)ipc4, ipc->comp_data,
 				    &reply_size);
 	/* reply size is returned in header extension dword */
 	msg_reply.extension = reply_size;
 
 	if (reply_size > 0) {
-		msg_reply.tx_data = rballoc(0, SOF_MEM_CAPS_RAM, reply_size);
-		if (msg_reply.tx_data) {
-			msg_reply.tx_size = reply_size;
-		} else {
-			ipc_cmd_err(&ipc_tr, "failed to allocate %u bytes for msg_reply.tx_data",
-				    reply_size);
-			msg_reply.extension = 0;
-			return IPC4_OUT_OF_MEMORY;
-		}
+		msg_reply.tx_data = ipc->comp_data;
+		msg_reply.tx_size = reply_size;
 	}
 
 	return err < 0 ? IPC4_FAILURE : IPC4_SUCCESS;
@@ -1054,7 +1039,6 @@ static int ipc4_get_large_config_module_instance(struct ipc4_message_request *ip
 	const struct comp_driver *drv;
 	struct comp_dev *dev = NULL;
 	uint32_t data_offset;
-	void *response_buffer;
 	int ret = memcpy_s(&config, sizeof(config), ipc4, sizeof(*ipc4));
 
 	if (ret < 0)
@@ -1134,15 +1118,8 @@ static int ipc4_get_large_config_module_instance(struct ipc4_message_request *ip
 		return ret;
 
 	msg_reply.extension = reply.extension.dat;
-	response_buffer = rballoc(0, SOF_MEM_CAPS_RAM, data_offset);
-	if (response_buffer) {
-		msg_reply.tx_size = data_offset;
-		msg_reply.tx_data = response_buffer;
-	} else {
-		ipc_cmd_err(&ipc_tr, "error: failed to allocate tx_data");
-		ret = IPC4_OUT_OF_MEMORY;
-	}
-
+	msg_reply.tx_size = data_offset;
+	msg_reply.tx_data = data;
 	return ret;
 }
 
@@ -1494,26 +1471,8 @@ struct ipc_cmd_hdr *ipc_prepare_to_send(const struct ipc_msg *msg)
 	msg_data.msg_out.pri = msg->header;
 	msg_data.msg_out.ext = msg->extension;
 
-	if (msg->tx_size) {
-		/* Invalidate cache to ensure we read the latest data from memory.
-		 * The response was prepared on a secondary core but will be sent
-		 * to the host from the primary core.
-		 */
-		if (msg->is_shared) {
-			dcache_invalidate_region((__sparse_force void __sparse_cache *)msg->tx_data,
-						 msg->tx_size);
-		}
-
+	if (msg->tx_size)
 		mailbox_dspbox_write(0, (uint32_t *)msg->tx_data, msg->tx_size);
-	}
-
-	/* free memory for get config function */
-	if (msg == &msg_reply && msg_reply.tx_size > 0) {
-		rfree(msg_reply.tx_data);
-		msg_reply.tx_data = NULL;
-		msg_reply.tx_size = 0;
-		msg_reply.is_shared = false;
-	}
 
 	return &msg_data.msg_out;
 }
@@ -1546,7 +1505,6 @@ void ipc_send_panic_notification(void)
 {
 	msg_notify.header = SOF_IPC4_NOTIF_HEADER(SOF_IPC4_EXCEPTION_CAUGHT);
 	msg_notify.extension = cpu_get_id();
-	msg_notify.is_shared = !cpu_is_primary(cpu_get_id());
 	msg_notify.tx_size = 0;
 	msg_notify.tx_data = NULL;
 	list_init(&msg_notify.list);
@@ -1579,7 +1537,6 @@ void ipc_send_buffer_status_notify(void)
 	msg_notify.header = SOF_IPC4_NOTIF_HEADER(SOF_IPC4_NOTIFY_LOG_BUFFER_STATUS);
 	msg_notify.extension = 0;
 	msg_notify.tx_size = 0;
-	msg_notify.is_shared = false;
 
 	tr_dbg(&ipc_tr, "tx-notify\t: %#x|%#x", msg_notify.header, msg_notify.extension);
 
@@ -1607,6 +1564,7 @@ void ipc_cmd(struct ipc_cmd_hdr *_hdr)
 	/* no process on scheduled thread */
 	atomic_set(&msg_data.delayed_reply, 0);
 	msg_data.delayed_error = 0;
+	msg_reply.tx_data = NULL;
 	msg_reply.tx_size = 0;
 	msg_reply.header = in->primary.dat;
 	msg_reply.extension = in->extension.dat;
diff --git a/src/library_manager/lib_notification.c b/src/library_manager/lib_notification.c
index f76fc05942b1..29ca2de2a951 100644
--- a/src/library_manager/lib_notification.c
+++ b/src/library_manager/lib_notification.c
@@ -73,7 +73,6 @@ struct ipc_msg *lib_notif_msg_init(uint32_t header, uint32_t size)
 	/* Update header and size, since message handle can be reused */
 	msg->header = header;
 	msg->tx_size = size;
-	msg->is_shared = !cpu_is_primary(cpu_get_id());
 	return msg;
 }