From patchwork Thu Jul 23 17:35:04 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Maciej Fijalkowski X-Patchwork-Id: 1335001 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: incoming-bpf@patchwork.ozlabs.org Delivered-To: patchwork-incoming-bpf@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=bpf-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=intel.com Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4BCKNg18VZz9sRR for ; Fri, 24 Jul 2020 03:40:19 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730180AbgGWRkS (ORCPT ); Thu, 23 Jul 2020 13:40:18 -0400 Received: from mga06.intel.com ([134.134.136.31]:56227 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726666AbgGWRkQ (ORCPT ); Thu, 23 Jul 2020 13:40:16 -0400 IronPort-SDR: PlG8WkeFKGPdlqn8I1BcMjMc4gPHx/N/qL2C6KJw+GwPeV9xsdNZzRCyRJCqlcseJO4GJaGsoa cPRZewkhF23g== X-IronPort-AV: E=McAfee;i="6000,8403,9691"; a="212124555" X-IronPort-AV: E=Sophos;i="5.75,387,1589266800"; d="scan'208";a="212124555" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Jul 2020 10:40:16 -0700 IronPort-SDR: 3bbGuuME/b8hfbyGZZrD/VLT9gyx1EnJdYlZ/or5kfk/H7i1OMF3uN1AFz03oOV90RuVNhJH8A F2c9pN46InzA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.75,387,1589266800"; d="scan'208";a="462940302" Received: from ranger.igk.intel.com ([10.102.21.164]) by orsmga005.jf.intel.com with ESMTP; 23 Jul 2020 10:40:14 -0700 From: Maciej Fijalkowski To: ast@kernel.org, daniel@iogearbox.net Cc: bpf@vger.kernel.org, netdev@vger.kernel.org, bjorn.topel@intel.com, magnus.karlsson@intel.com, Maciej Fijalkowski Subject: [PATCH v3 bpf-next 2/6] bpf: propagate poke descriptors to subprograms Date: Thu, 23 Jul 2020 19:35:04 +0200 Message-Id: <20200723173508.62285-3-maciej.fijalkowski@intel.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200723173508.62285-1-maciej.fijalkowski@intel.com> References: <20200723173508.62285-1-maciej.fijalkowski@intel.com> MIME-Version: 1.0 Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org 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 --- kernel/bpf/verifier.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 9a6703bc3f36..0cf5e4e4af95 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -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])