Re: [PATCH bpf-next 0/4] bpf: tailcall: Eliminate max_entries and bpf_func access at runtime

On Wed, Jan 14, 2026 at 01:56:11PM -0800, Alexei Starovoitov wrote:

On Wed, Jan 14, 2026 at 1:00 PM Jiri Olsa [off-list ref] wrote:

quoted

quoted

quoted

fyi I briefly discussed that with Andrii indicating that it might not
be worth the effort at this stage.

depending on complexity of course.

for my tests I just had to allow BPF_MAP_TYPE_PROG_ARRAY map
for sleepable programs

jirka


---

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index faa1ecc1fe9d..1f6fc74c7ea1 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c

@@ -20969,6 +20969,7 @@ static int check_map_prog_compatibility(struct bpf_verifier_env *env,
                case BPF_MAP_TYPE_STACK:
                case BPF_MAP_TYPE_ARENA:
                case BPF_MAP_TYPE_INSN_ARRAY:
+               case BPF_MAP_TYPE_PROG_ARRAY:
                        break;
                default:
                        verbose(env,

Think it through, add selftests, ship it.
On the surface the easy part is to make
__bpf_prog_map_compatible() reject sleepable/non-sleepable combo.
Maybe there are other things.

ok, thanks

jirka