diff --git a/c_src/cmd_format.c b/c_src/cmd_format.c
index e2468350..4bafa171 100644
--- a/c_src/cmd_format.c
+++ b/c_src/cmd_format.c
@@ -128,6 +128,9 @@ int cmd_format(int argc, char *argv[])
 		bch2_cmdline_opts_get(&argc, argv, OPT_FORMAT);
 	struct bch_opts fs_opts = bch2_parse_opts(fs_opt_strs);
 
+	if (getenv("BCACHEFS_KERNEL_ONLY"))
+		initialize = false;
+
 	while ((opt = getopt_long(argc, argv,
 				  "-L:U:g:fqhv",
 				  format_opts,
diff --git a/c_src/cmd_fsck.c b/c_src/cmd_fsck.c
index 05582d4a..f1f4ae89 100644
--- a/c_src/cmd_fsck.c
+++ b/c_src/cmd_fsck.c
@@ -171,6 +171,9 @@ int cmd_fsck(int argc, char *argv[])
 	int opt, ret = 0;
 	struct printbuf opts_str = PRINTBUF;
 
+	if (getenv("BCACHEFS_KERNEL_ONLY"))
+		kernel = true;
+
 	append_opt(&opts_str, "degraded");
 	append_opt(&opts_str, "fsck");
 	append_opt(&opts_str, "fix_errors=ask");