diff options
| author | Eduard Zingerman <eddyz87@gmail.com> | 2025-09-18 19:18:38 -0700 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2025-09-19 09:27:23 -0700 |
| commit | efcda22aa541bbda827e54302baf9ae4fd44cdf2 (patch) | |
| tree | dcdf69e01ee90925e00d2322b481f28465f9aa84 /include | |
| parent | 3b20d3c120bae1e18ee11aa04531b161743db682 (diff) | |
bpf: compute instructions postorder per subprogram
The next patch would require doing postorder traversal of individual
subprograms. Facilitate this by moving env->cfg.insn_postorder
computation from check_cfg() to a separate pass, as check_cfg()
descends into called subprograms (and it needs to, because of
merge_callee_effects() logic).
env->cfg.insn_postorder is used only by compute_live_registers(),
this function does not track cross subprogram dependencies,
thus the change does not affect it's operation.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250918-callchain-sensitive-liveness-v3-5-c3cd27bacc60@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/bpf_verifier.h | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h index 93563564bde5..bd87e80f9423 100644 --- a/include/linux/bpf_verifier.h +++ b/include/linux/bpf_verifier.h @@ -665,6 +665,7 @@ struct bpf_subprog_info { /* 'start' has to be the first field otherwise find_subprog() won't work */ u32 start; /* insn idx of function entry point */ u32 linfo_idx; /* The idx to the main_prog->aux->linfo */ + u32 postorder_start; /* The idx to the env->cfg.insn_postorder */ u16 stack_depth; /* max. stack depth used by this function */ u16 stack_extra; /* offsets in range [stack_depth .. fastcall_stack_off) @@ -794,7 +795,10 @@ struct bpf_verifier_env { struct { int *insn_state; int *insn_stack; - /* vector of instruction indexes sorted in post-order */ + /* + * vector of instruction indexes sorted in post-order, grouped by subprogram, + * see bpf_subprog_info->postorder_start. + */ int *insn_postorder; int cur_stack; /* current position in the insn_postorder vector */ |