diff --git a/engines/sg.c b/engines/sg.c
index 24783374cb..0bb5be4a9d 100644
--- a/engines/sg.c
+++ b/engines/sg.c
@@ -1428,7 +1428,7 @@ static struct ioengine_ops ioengine = {
 	.open_file	= fio_sgio_open,
 	.close_file	= fio_sgio_close,
 	.get_file_size	= fio_sgio_get_file_size,
-	.flags		= FIO_SYNCIO | FIO_RAWIO,
+	.flags		= FIO_SYNCIO | FIO_RAWIO | FIO_RO_NEEDS_RW_OPEN,
 	.options	= options,
 	.option_struct_size	= sizeof(struct sg_options)
 };
diff --git a/filesetup.c b/filesetup.c
index 1d3cc5ad9e..cb7047c5af 100644
--- a/filesetup.c
+++ b/filesetup.c
@@ -768,7 +768,7 @@ int generic_open_file(struct thread_data *td, struct fio_file *f)
 		else
 			from_hash = file_lookup_open(f, flags);
 	} else if (td_read(td)) {
-		if (f->filetype == FIO_TYPE_CHAR && !read_only)
+		if (td_ioengine_flagged(td, FIO_RO_NEEDS_RW_OPEN) && !read_only)
 			flags |= O_RDWR;
 		else
 			flags |= O_RDONLY;
diff --git a/ioengines.h b/ioengines.h
index d43540d0f6..2cb9743e8e 100644
--- a/ioengines.h
+++ b/ioengines.h
@@ -89,6 +89,8 @@ enum fio_ioengine_flags {
 			= 1 << 16,	/* async ioengine with commit function that sets issue_time */
 	FIO_SKIPPABLE_IOMEM_ALLOC
 			= 1 << 17,	/* skip iomem_alloc & iomem_free if job sets mem/iomem */
+	FIO_RO_NEEDS_RW_OPEN
+			= 1 << 18,	/* open files in rw mode even if we have a read job */
 };
 
 /*