Commit 6cd21eb9 authored by Eduard Zingerman's avatar Eduard Zingerman Committed by Alexei Starovoitov
Browse files

bpf: use compute_live_registers() info in clean_func_state 



Prepare for bpf_reg_state->live field removal by leveraging
insn_aux_data->live_regs_before instead of bpf_reg_state->live in
compute_live_registers(). This is similar to logic in
func_states_equal(). No changes in verification performance for
selftests or sched_ext.

Signed-off-by: default avatarEduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250918-callchain-sensitive-liveness-v3-2-c3cd27bacc60@gmail.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent daf4c292

kernel/bpf/verifier.c

+9 −6
Original line number Diff line number Diff line
@@ -18489,15 +18489,16 @@ static bool check_scalar_ids(u32 old_id, u32 cur_id, struct bpf_idmap *idmap) 
}









static void clean_func_state(struct bpf_verifier_env *env,









			     struct bpf_func_state *st)









			     struct bpf_func_state *st,









			     u32 ip)









{









	u16 live_regs = env->insn_aux_data[ip].live_regs_before;









	enum bpf_reg_liveness live;









	int i, j;

















	for (i = 0; i < BPF_REG_FP; i++) {









		live = st->regs[i].live;









		/* liveness must not touch this register anymore */









		if (!(live & REG_LIVE_READ))









		if (!(live_regs & BIT(i)))









			/* since the register is unused, clear its state









			 * to make further comparison simpler









			 */








@@ -18518,11 +18519,13 @@ static void clean_func_state(struct bpf_verifier_env *env,







static void clean_verifier_state(struct bpf_verifier_env *env,









				 struct bpf_verifier_state *st)









{









	int i;









	int i, ip;

















	st->cleaned = true;









	for (i = 0; i <= st->curframe; i++)









		clean_func_state(env, st->frame[i]);









	for (i = 0; i <= st->curframe; i++) {









		ip = frame_insn_idx(st, i);









		clean_func_state(env, st->frame[i], ip);









	}









}

















/* the parentage chains form a tree.