On Thu, 2022-04-28 at 11:33 -0700, Andrii Nakryiko wrote: > On Thu, Apr 28, 2022 at 9:54 AM Delyan Kratunov <delyank@xxxxxx> wrote: > > > > Add section mappings for uprobe.s and kprobe.s programs. The latter > > cannot currently attach but they're still useful to open and load in > > order to validate that prohibition. > > > > This patch made me realize that some changes I did few weeks ago > hasn't landed ([0]). I'm going to rebase and resubmit and I'll ask you > to rebase on top of those changes. > > [0] https://patchwork.kernel.org/project/netdevbpf/list/?series=630550&state=* > > > Signed-off-by: Delyan Kratunov <delyank@xxxxxx> > > --- > > tools/lib/bpf/libbpf.c | 10 +++++++++- > > 1 file changed, 9 insertions(+), 1 deletion(-) > > > > diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c > > index 9a213aaaac8a..9e89a478d40e 100644 > > --- a/tools/lib/bpf/libbpf.c > > +++ b/tools/lib/bpf/libbpf.c > > @@ -8692,9 +8692,12 @@ static const struct bpf_sec_def section_defs[] = { > > SEC_DEF("sk_reuseport/migrate", SK_REUSEPORT, BPF_SK_REUSEPORT_SELECT_OR_MIGRATE, SEC_ATTACHABLE | SEC_SLOPPY_PFX), > > SEC_DEF("sk_reuseport", SK_REUSEPORT, BPF_SK_REUSEPORT_SELECT, SEC_ATTACHABLE | SEC_SLOPPY_PFX), > > SEC_DEF("kprobe/", KPROBE, 0, SEC_NONE, attach_kprobe), > > + SEC_DEF("kprobe.s/", KPROBE, 0, SEC_SLEEPABLE, attach_kprobe), > > but do we really have sleepable kprobes supported in the kernel? I > don't think yet, let's not advertise as if SEC("kprobe.s") is a thing > until we do Fair enough, I was being lazy. I'll have the test explicitly set flags/type, it's not that hard anyway. > > SEC_DEF("uprobe+", KPROBE, 0, SEC_NONE, attach_uprobe), > > + SEC_DEF("uprobe.s+", KPROBE, 0, SEC_SLEEPABLE, attach_uprobe), > > SEC_DEF("kretprobe/", KPROBE, 0, SEC_NONE, attach_kprobe), > > SEC_DEF("uretprobe+", KPROBE, 0, SEC_NONE, attach_uprobe), > > + SEC_DEF("uretprobe.s+", KPROBE, 0, SEC_SLEEPABLE, attach_uprobe), > > SEC_DEF("kprobe.multi/", KPROBE, BPF_TRACE_KPROBE_MULTI, SEC_NONE, attach_kprobe_multi), > > SEC_DEF("kretprobe.multi/", KPROBE, BPF_TRACE_KPROBE_MULTI, SEC_NONE, attach_kprobe_multi), > > SEC_DEF("usdt+", KPROBE, 0, SEC_NONE, attach_usdt), > > @@ -10432,13 +10435,18 @@ static int attach_kprobe(const struct bpf_program *prog, long cookie, struct bpf > > const char *func_name; > > char *func; > > int n; > > + bool sleepable = false; > > > > opts.retprobe = str_has_pfx(prog->sec_name, "kretprobe/"); > > + sleepable = str_has_pfx(prog->sec_name, "kprobe.s/"); > > if (opts.retprobe) > > func_name = prog->sec_name + sizeof("kretprobe/") - 1; > > + else if (sleepable) > > + func_name = prog->sec_name + sizeof("kprobe.s/") - 1; > > else > > func_name = prog->sec_name + sizeof("kprobe/") - 1; > > > > + > > n = sscanf(func_name, "%m[a-zA-Z0-9_.]+%li", &func, &offset); > > if (n < 1) { > > pr_warn("kprobe name is invalid: %s\n", func_name); > > @@ -10957,7 +10965,7 @@ static int attach_uprobe(const struct bpf_program *prog, long cookie, struct bpf > > break; > > case 3: > > case 4: > > - opts.retprobe = strcmp(probe_type, "uretprobe") == 0; > > + opts.retprobe = str_has_pfx(probe_type, "uretprobe"); > > it's a total nit but I'd feel a bit more comfortable with explicit > check for "uretprobe" and "uretprobe.s" instead of a prefix match, if > you don't mind. Sure. > > > if (opts.retprobe && offset != 0) { > > pr_warn("prog '%s': uretprobes do not support offset specification\n", > > prog->name); > > -- > > 2.35.1
