sbat.c: add user facing message when SBAT self check fails

This also increases the time until shutdown to 8 seconds.

Signed-off-by: Thore Sommer <[email protected]>

Author: THS-on

shim.c

@@ -1966,10 +1966,18 @@ efi_main (EFI_HANDLE passed_image_handle, EFI_SYSTEM_TABLE *passed_systab)
 die:
 		console_print(L"Something has gone seriously wrong: %s: %r\n",
 			      msgs[msg], efi_status);
+
+		/*
+		 * Provide additional information when the SBAT self check fails
+		 */
+		if ( msg == SBAT_SELF_CHECK ) {
+			console_print(L"\nThe current shim has likely been revoked. " 
+						   "Please update to a newer shim version.\n");
+		}
 #if defined(ENABLE_SHIM_DEVEL)
 		devel_egress(COLD_RESET);
 #else
-		usleep(5000000);
+		usleep(8000000);
 		RT->ResetSystem(EfiResetShutdown, EFI_SECURITY_VIOLATION,
 				0, NULL);
 #endif