From 082b57e3eb09810d357083cca5ee2df02c16aec9 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Maciej=20=C5=BBenczykowski?= Date: Mon, 20 Apr 2020 11:47:50 -0700 Subject: [PATCH] net: bpf: Make bpf_ktime_get_ns() available to non GPL programs MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The entire implementation is in kernel/bpf/helpers.c: BPF_CALL_0(bpf_ktime_get_ns) { /* NMI safe access to clock monotonic */ return ktime_get_mono_fast_ns(); } const struct bpf_func_proto bpf_ktime_get_ns_proto = { .func = bpf_ktime_get_ns, .gpl_only = false, .ret_type = RET_INTEGER, }; and this was presumably marked GPL due to kernel/time/timekeeping.c: EXPORT_SYMBOL_GPL(ktime_get_mono_fast_ns); and while that may make sense for kernel modules (although even that is doubtful), there is currently AFAICT no other source of time available to ebpf. Furthermore this is really just equivalent to clock_gettime(CLOCK_MONOTONIC) which is exposed to userspace (via vdso even to make it performant)... As such, I see no reason to keep the GPL restriction. (In the future I'd like to have access to time from Apache licensed ebpf code) Signed-off-by: Maciej Żenczykowski Signed-off-by: Alexei Starovoitov --- kernel/bpf/helpers.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index dbba4f41d508..9a6b23387d02 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -151,7 +151,7 @@ BPF_CALL_0(bpf_ktime_get_ns) const struct bpf_func_proto bpf_ktime_get_ns_proto = { .func = bpf_ktime_get_ns, - .gpl_only = true, + .gpl_only = false, .ret_type = RET_INTEGER, };