@@ -9900,6 +9900,7 @@ static int jit_subprogs(struct bpf_verifier_env *env)
{
struct bpf_prog *prog = env->prog, **func, *tmp;
int i, j, subprog_start, subprog_end = 0, len, subprog;
+ struct bpf_map *map_ptr;
struct bpf_insn *insn;
void *old_bpf_func;
int err, num_exentries;
@@ -9943,6 +9944,8 @@ static int jit_subprogs(struct bpf_verifier_env *env)
goto out_undo_insn;
for (i = 0; i < env->subprog_cnt; i++) {
+ int j;
+
subprog_start = subprog_end;
subprog_end = env->subprog_info[i + 1].start;
@@ -9967,6 +9970,23 @@ static int jit_subprogs(struct bpf_verifier_env *env)
func[i]->aux->btf = prog->aux->btf;
func[i]->aux->func_info = prog->aux->func_info;
+ for (j = 0; j < prog->aux->size_poke_tab; j++) {
+ int ret;
+
+ ret = bpf_jit_add_poke_descriptor(func[i],
+ &prog->aux->poke_tab[j]);
+ if (ret < 0) {
+ verbose(env, "adding tail call poke descriptor failed\n");
+ goto out_untrack;
+ }
+ map_ptr = func[i]->aux->poke_tab[j].tail_call.map;
+ ret = map_ptr->ops->map_poke_track(map_ptr, func[i]->aux);
+ if (ret < 0) {
+ verbose(env, "tracking tail call prog failed\n");
+ goto out_untrack;
+ }
+ }
+
/* Use bpf_prog_F_tag to indicate functions in stack traces.
* Long term would need debug info to populate names
*/
@@ -10059,6 +10079,17 @@ static int jit_subprogs(struct bpf_verifier_env *env)
prog->aux->func_cnt = env->subprog_cnt;
bpf_prog_free_unused_jited_linfo(prog);
return 0;
+out_untrack:
+ while (j--) {
+ map_ptr = func[i]->aux->poke_tab[j].tail_call.map;
+ map_ptr->ops->map_poke_untrack(map_ptr, func[i]->aux);
+ }
+ while (i--) {
+ for (j = 0; j < prog->aux->size_poke_tab; j++) {
+ map_ptr = func[i]->aux->poke_tab[j].tail_call.map;
+ map_ptr->ops->map_poke_untrack(map_ptr, func[i]->aux);
+ }
+ }
out_free:
for (i = 0; i < env->subprog_cnt; i++)
if (func[i])
Previously, there was no need for poke descriptors being present in subprogram's bpf_prog_aux struct since tailcalls were simply not allowed in them. Each subprog is JITed independently so in order to enable JITing such subprograms, simply copy poke descriptors from main program to subprogram's poke tab. Add also subprog's aux struct to the BPF map poke_progs list by calling on it map_poke_track(). In case of any error, call the map_poke_untrack() on subprog's aux structs that have already been registered to prog array map. Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> --- kernel/bpf/verifier.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+)