1 files changed, 44 insertions, 5 deletions

diff --git a/drivers/acpi/prmt.c b/drivers/acpi/prmt.c
index 747f83f7114d..7b8b5d2015ec 100644
--- a/drivers/acpi/prmt.c
+++ b/drivers/acpi/prmt.c
@@ -85,8 +85,6 @@ static u64 efi_pa_va_lookup(efi_guid_t *guid, u64 pa)
 		}
 	}
 
-	pr_warn("Failed to find VA for GUID: %pUL, PA: 0x%llx", guid, pa);
-
 	return 0;
 }
 
@@ -152,15 +150,52 @@ acpi_parse_prmt(union acpi_subtable_headers *header, const unsigned long end)
 		th = &tm->handlers[cur_handler];
 
 		guid_copy(&th->guid, (guid_t *)handler_info->handler_guid);
+
+		/*
+		 * Print an error message if handler_address is NULL, the parse of VA also
+		 * can be skipped.
+		 */
+		if (unlikely(!handler_info->handler_address)) {
+			pr_info("Skipping handler with NULL address for GUID: %pUL",
+					(guid_t *)handler_info->handler_guid);
+			continue;
+		}
+
 		th->handler_addr =
 			(void *)efi_pa_va_lookup(&th->guid, handler_info->handler_address);
+		/*
+		 * Print a warning message and skip the parse of VA if handler_addr is zero
+		 * which is not expected to ever happen.
+		 */
+		if (unlikely(!th->handler_addr)) {
+			pr_warn("Failed to find VA of handler for GUID: %pUL, PA: 0x%llx",
+				&th->guid, handler_info->handler_address);
+			continue;
+		}
 
 		th->static_data_buffer_addr =
 			efi_pa_va_lookup(&th->guid, handler_info->static_data_buffer_address);
+		/*
+		 * According to the PRM specification, static_data_buffer_address can be zero,
+		 * so avoid printing a warning message in that case.  Otherwise, if the
+		 * return value of efi_pa_va_lookup() is zero, print the message.
+		 */
+		if (unlikely(!th->static_data_buffer_addr && handler_info->static_data_buffer_address))
+			pr_warn("Failed to find VA of static data buffer for GUID: %pUL, PA: 0x%llx",
+				&th->guid, handler_info->static_data_buffer_address);
 
 		th->acpi_param_buffer_addr =
 			efi_pa_va_lookup(&th->guid, handler_info->acpi_param_buffer_address);
 
+		/*
+		 * According to the PRM specification, acpi_param_buffer_address can be zero,
+		 * so avoid printing a warning message in that case.  Otherwise, if the
+		 * return value of efi_pa_va_lookup() is zero, print the message.
+		 */
+		if (unlikely(!th->acpi_param_buffer_addr && handler_info->acpi_param_buffer_address))
+			pr_warn("Failed to find VA of acpi param buffer for GUID: %pUL, PA: 0x%llx",
+				&th->guid, handler_info->acpi_param_buffer_address);
+
 	} while (++cur_handler < tm->handler_count && (handler_info = get_next_handler(handler_info)));
 
 	return 0;
@@ -209,6 +244,12 @@ static struct prm_handler_info *find_prm_handler(const guid_t *guid)
 	return (struct prm_handler_info *) find_guid_info(guid, GET_HANDLER);
 }
 
+bool acpi_prm_handler_available(const guid_t *guid)
+{
+	return find_prm_handler(guid) && find_prm_module(guid);
+}
+EXPORT_SYMBOL_GPL(acpi_prm_handler_available);
+
 /* In-coming PRM commands */
 
 #define PRM_CMD_RUN_SERVICE		0
@@ -287,9 +328,7 @@ static acpi_status acpi_platformrt_space_handler(u32 function,
 		if (!handler || !module)
 			goto invalid_guid;
 
-		if (!handler->handler_addr ||
-		    !handler->static_data_buffer_addr ||
-		    !handler->acpi_param_buffer_addr) {
+		if (!handler->handler_addr) {
 			buffer->prm_status = PRM_HANDLER_ERROR;
 			return AE_OK;
 		}