On 9/23/20 7:19 PM, Maciej Żenczykowski wrote:

quoted

diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index 5cc7425ee476..776ff58f969d 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c

@@ -155,6 +155,17 @@ const struct bpf_func_proto bpf_ktime_get_ns_proto = {
        .ret_type       = RET_INTEGER,
 };

+BPF_CALL_0(bpf_ktime_get_real_ns)
+{
+       /* NMI safe access to clock realtime */
+       return ktime_get_real_fast_ns();
+}
+
+const struct bpf_func_proto bpf_ktime_get_real_ns_proto = {
+       .func           = bpf_ktime_get_real_ns,
+       .gpl_only       = true,

imho should be false, this is normally accessible to userspace code
via syscall, no reason why it should be gpl only for bpf

agreed, no reason for the bpf hook to be gpl_only.

Glad to see the v2 of this patch; I wondered what happened to this helper.