HID: bpf: reorder BPF registration

Given that our initial BPF program is not using any kfuncs anymore,
we can reorder the initialization to first try to load it and then
register the kfuncs. This has the advantage of not exporting kfuncs
when HID-BPF is not working.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

diff --git a/drivers/hid/bpf/hid_bpf_dispatch.c b/drivers/hid/bpf/hid_bpf_dispatch.c
index 26117b4ec016badf3e6d99a9e27ae649bd651baf..8a034a555d4ce8570e99688fd93e211fdf1aa049 100644 (file)
--- a/drivers/hid/bpf/hid_bpf_dispatch.c
+++ b/drivers/hid/bpf/hid_bpf_dispatch.c
@@ -514,15 +514,16 @@ static int __init hid_bpf_init(void)
                return 0;
        }
 
-       err = register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING, &hid_bpf_kfunc_set);
+       err = hid_bpf_preload_skel();
        if (err) {
-               pr_warn("error while setting HID BPF tracing kfuncs: %d", err);
+               pr_warn("error while preloading HID BPF dispatcher: %d", err);
                return 0;
        }
 
-       err = hid_bpf_preload_skel();
+       /* register tracing kfuncs after we are sure we can load our preloaded bpf program */
+       err = register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING, &hid_bpf_kfunc_set);
        if (err) {
-               pr_warn("error while preloading HID BPF dispatcher: %d", err);
+               pr_warn("error while setting HID BPF tracing kfuncs: %d", err);
                return 0;
        }