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Date: Wed, 1 Oct 2025 19:51:26 +0530 Message-ID: <20251001142127.37559-1-suchitkarunakaran@gmail.com> X-Mailer: git-send-email 2.51.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Hi folks, While going through the verifier code, I noticed that the integer return value of mark_chain_precision() is ignored within loop_flag_is_zero(). static bool loop_flag_is_zero(struct bpf_verifier_env *env) { struct bpf_reg_state *regs = cur_regs(env); struct bpf_reg_state *reg = ®s[BPF_REG_4]; bool reg_is_null = register_is_null(reg); if (reg_is_null) mark_chain_precision(env, BPF_REG_4); return reg_is_null; } My question is: Is this behavior intentional (i.e., errors from mark_chain_precision() are safe to ignore here)? Or should loop_flag_is_zero() propagate the error to update_loop_inline_state() and from there to check_helper_call() function? I’d appreciate any clarification or suggestions. Apologies if this kind of question isn’t appropriate for the mailing list, I wanted to clarify the intended semantics before attempting a fix. Thanks, Suchit Karunakaran