From patchwork Tue Mar 21 05:19:48 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexei Starovoitov X-Patchwork-Id: 13182261 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5CC3AC74A5B for ; Tue, 21 Mar 2023 05:20:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229810AbjCUFUF (ORCPT ); Tue, 21 Mar 2023 01:20:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38006 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229813AbjCUFUE (ORCPT ); Tue, 21 Mar 2023 01:20:04 -0400 Received: from mail-pf1-x42f.google.com (mail-pf1-x42f.google.com [IPv6:2607:f8b0:4864:20::42f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 83BA239B88; Mon, 20 Mar 2023 22:20:00 -0700 (PDT) Received: by mail-pf1-x42f.google.com with SMTP id fd25so8291386pfb.1; Mon, 20 Mar 2023 22:20:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; t=1679376000; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=vbvMiertEJLycVloMHKS7yMvdcuq9AftYH+u/ksDT6U=; b=ZHGPx94+oTMQP0IdCJr+9WCMNvue+WefV29UEIqxeS/dO5A1HfwOD762W/KPReZFhW 7aggWJjyVf/K8Cq7614cToRizHCOw4S6GrUodSgdGMX7R8BC+IbfTa76uAHl3XvAhjOc Bc1s5XARn9n/OhhMtAkhH8PR70WUMauyi83JuysHyDDbdKnJnYqUWgilIbdml4Drp5Wp yu/yGFh1pAv0vqIalT8mIoyb1qxWbyZ4dphZWgebrJ8UgrDdIOny7+5rlz/T3SFuV4T4 tvfYksFhZ2KjOgurelrmIO/Vovf0babttgp44wS/pCvLgdEMdeZtaKsb4POpSEP0KUqL iQsQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1679376000; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=vbvMiertEJLycVloMHKS7yMvdcuq9AftYH+u/ksDT6U=; b=suvkkgrWTQSg7dOV98rxFZxR8MCAy4gHWYikfRkXBR69FZj7nWG/xQYRjDPsz0QOOx Y+f+7Pnfw/t3xgv96+EtvoqN4V4f4TAsOTAC4FvY07jaEJZXZ4RMhaRsPZhKpAQbOlY6 ut8nDbyS7C0d+T3c4KZq6YBjzQYC1A38k+WFTr321TI783ZkMkagrYtBZ4WPMUzxY48p hGeCSUsf9yynBLPSCscBR7hOMZh4ZWud+MfqBv/k+L5P57JOjM8BbogbXLSvtoyoRYw3 k7+tKzOF7YvZ/YWOYg7yMh0G7/MwNAxGlpMWW1S7FYD5eCfeYqix1D4QPwXZh3kmXMUR Lf4w== X-Gm-Message-State: AO0yUKWlzgt75DOGci7Pt51suH5luJaLvU/4tskF/GYxzlgvd5TZOKDV 4Ig8l9+HWjKyldohzNyyM2PFZaPijb8= X-Google-Smtp-Source: AK7set+fgai7lOYDzZP926ZJAX6mtZ9b/uW96FNcmEhtH5TFIiHpiUyf5uVcMkrIdepGNlnrDHd/iQ== X-Received: by 2002:aa7:957c:0:b0:626:dc8:b004 with SMTP id x28-20020aa7957c000000b006260dc8b004mr1398154pfq.26.1679375999923; Mon, 20 Mar 2023 22:19:59 -0700 (PDT) Received: from dhcp-172-26-102-232.DHCP.thefacebook.com ([2620:10d:c090:400::5:1606]) by smtp.gmail.com with ESMTPSA id f17-20020a63de11000000b004fc1d91e695sm7168298pgg.79.2023.03.20.22.19.58 (version=TLS1_3 cipher=TLS_CHACHA20_POLY1305_SHA256 bits=256/256); Mon, 20 Mar 2023 22:19:59 -0700 (PDT) From: Alexei Starovoitov To: davem@davemloft.net Cc: daniel@iogearbox.net, andrii@kernel.org, martin.lau@kernel.org, void@manifault.com, davemarchevsky@meta.com, tj@kernel.org, memxor@gmail.com, netdev@vger.kernel.org, bpf@vger.kernel.org, kernel-team@fb.com Subject: [PATCH bpf-next 1/4] libbpf: Rename RELO_EXTERN_VAR/FUNC. Date: Mon, 20 Mar 2023 22:19:48 -0700 Message-Id: <20230321051951.58223-2-alexei.starovoitov@gmail.com> X-Mailer: git-send-email 2.37.1 (Apple Git-137.1) In-Reply-To: <20230321051951.58223-1-alexei.starovoitov@gmail.com> References: <20230321051951.58223-1-alexei.starovoitov@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net From: Alexei Starovoitov RELO_EXTERN_VAR/FUNC names are not correct anymore. RELO_EXTERN_VAR represent ksym symbol in ld_imm64 insn. It can point to kernel variable or kfunc. Rename RELO_EXTERN_VAR->RELO_EXTERN_LD64 and RELO_EXTERN_FUNC->RELO_EXTERN_CALL to match what they actually represent. Signed-off-by: Alexei Starovoitov --- tools/lib/bpf/libbpf.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 149864ea88d1..f8131f963803 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -315,8 +315,8 @@ enum reloc_type { RELO_LD64, RELO_CALL, RELO_DATA, - RELO_EXTERN_VAR, - RELO_EXTERN_FUNC, + RELO_EXTERN_LD64, + RELO_EXTERN_CALL, RELO_SUBPROG_ADDR, RELO_CORE, }; @@ -4009,9 +4009,9 @@ static int bpf_program__record_reloc(struct bpf_program *prog, pr_debug("prog '%s': found extern #%d '%s' (sym %d) for insn #%u\n", prog->name, i, ext->name, ext->sym_idx, insn_idx); if (insn->code == (BPF_JMP | BPF_CALL)) - reloc_desc->type = RELO_EXTERN_FUNC; + reloc_desc->type = RELO_EXTERN_CALL; else - reloc_desc->type = RELO_EXTERN_VAR; + reloc_desc->type = RELO_EXTERN_LD64; reloc_desc->insn_idx = insn_idx; reloc_desc->sym_off = i; /* sym_off stores extern index */ return 0; @@ -5855,7 +5855,7 @@ bpf_object__relocate_data(struct bpf_object *obj, struct bpf_program *prog) relo->map_idx, map); } break; - case RELO_EXTERN_VAR: + case RELO_EXTERN_LD64: ext = &obj->externs[relo->sym_off]; if (ext->type == EXT_KCFG) { if (obj->gen_loader) { @@ -5877,7 +5877,7 @@ bpf_object__relocate_data(struct bpf_object *obj, struct bpf_program *prog) } } break; - case RELO_EXTERN_FUNC: + case RELO_EXTERN_CALL: ext = &obj->externs[relo->sym_off]; insn[0].src_reg = BPF_PSEUDO_KFUNC_CALL; if (ext->is_set) { @@ -6115,7 +6115,7 @@ bpf_object__reloc_code(struct bpf_object *obj, struct bpf_program *main_prog, continue; relo = find_prog_insn_relo(prog, insn_idx); - if (relo && relo->type == RELO_EXTERN_FUNC) + if (relo && relo->type == RELO_EXTERN_CALL) /* kfunc relocations will be handled later * in bpf_object__relocate_data() */ @@ -7072,14 +7072,14 @@ static int bpf_program_record_relos(struct bpf_program *prog) struct extern_desc *ext = &obj->externs[relo->sym_off]; switch (relo->type) { - case RELO_EXTERN_VAR: + case RELO_EXTERN_LD64: if (ext->type != EXT_KSYM) continue; bpf_gen__record_extern(obj->gen_loader, ext->name, ext->is_weak, !ext->ksym.type_id, BTF_KIND_VAR, relo->insn_idx); break; - case RELO_EXTERN_FUNC: + case RELO_EXTERN_CALL: bpf_gen__record_extern(obj->gen_loader, ext->name, ext->is_weak, false, BTF_KIND_FUNC, relo->insn_idx); From patchwork Tue Mar 21 05:19:49 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexei Starovoitov X-Patchwork-Id: 13182262 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 84C9EC761AF for ; Tue, 21 Mar 2023 05:20:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229816AbjCUFUH (ORCPT ); Tue, 21 Mar 2023 01:20:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38046 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229876AbjCUFUG (ORCPT ); Tue, 21 Mar 2023 01:20:06 -0400 Received: from mail-pj1-x1033.google.com (mail-pj1-x1033.google.com [IPv6:2607:f8b0:4864:20::1033]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 300B3399EB; 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Mon, 20 Mar 2023 22:20:03 -0700 (PDT) From: Alexei Starovoitov To: davem@davemloft.net Cc: daniel@iogearbox.net, andrii@kernel.org, martin.lau@kernel.org, void@manifault.com, davemarchevsky@meta.com, tj@kernel.org, memxor@gmail.com, netdev@vger.kernel.org, bpf@vger.kernel.org, kernel-team@fb.com Subject: [PATCH bpf-next 2/4] bpf: Teach the verifier to recognize rdonly_mem as not null. Date: Mon, 20 Mar 2023 22:19:49 -0700 Message-Id: <20230321051951.58223-3-alexei.starovoitov@gmail.com> X-Mailer: git-send-email 2.37.1 (Apple Git-137.1) In-Reply-To: <20230321051951.58223-1-alexei.starovoitov@gmail.com> References: <20230321051951.58223-1-alexei.starovoitov@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net From: Alexei Starovoitov Teach the verifier to recognize PTR_TO_MEM | MEM_RDONLY as not NULL otherwise if (!bpf_ksym_exists(known_kfunc)) doesn't go through dead code elimination. Signed-off-by: Alexei Starovoitov --- kernel/bpf/verifier.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 8bc44f5dc5b6..5693e4a92752 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -486,8 +486,17 @@ static bool type_is_sk_pointer(enum bpf_reg_type type) type == PTR_TO_XDP_SOCK; } +static bool type_may_be_null(u32 type) +{ + return type & PTR_MAYBE_NULL; +} + static bool reg_type_not_null(enum bpf_reg_type type) { + if (type_may_be_null(type)) + return false; + + type = base_type(type); return type == PTR_TO_SOCKET || type == PTR_TO_TCP_SOCK || type == PTR_TO_MAP_VALUE || @@ -531,11 +540,6 @@ static bool type_is_rdonly_mem(u32 type) return type & MEM_RDONLY; } -static bool type_may_be_null(u32 type) -{ - return type & PTR_MAYBE_NULL; -} - static bool is_acquire_function(enum bpf_func_id func_id, const struct bpf_map *map) { From patchwork Tue Mar 21 05:19:50 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexei Starovoitov X-Patchwork-Id: 13182263 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 46E04C76195 for ; Tue, 21 Mar 2023 05:20:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230005AbjCUFUR (ORCPT ); Tue, 21 Mar 2023 01:20:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38344 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229996AbjCUFUO (ORCPT ); Tue, 21 Mar 2023 01:20:14 -0400 Received: from mail-pl1-x636.google.com (mail-pl1-x636.google.com [IPv6:2607:f8b0:4864:20::636]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E259739CE4; Mon, 20 Mar 2023 22:20:08 -0700 (PDT) Received: by mail-pl1-x636.google.com with SMTP id le6so14880835plb.12; Mon, 20 Mar 2023 22:20:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; t=1679376008; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=Hlp+Ui1dMfarlEBa998LNtp9z3tMlr+TDoifOg7iOB0=; b=VXVl/xpHc9qAxmOCoY8rZyDqEGroMEbzH9dMVZsjhQlIeYdIWgGbt7enhmKoAAWZ1E sI/AKD4r7rdM3uEFEsIMgnuRK04CwQoMohmsr0THzdoZ9uKXbGeOIleit4DmxxYG2ET2 8M+xEvPDDqj+E/x+Q2Rq9KqLIyciU/99HOAmmgqC3ewqs/Lw8vdzFqWLEM9c5R/8bm4c Cz9QL2agS3cqVP8UZe8iJbDi9sFZiiR8CIJdKgBtng5i60kX0IgivaVUExKz5TXyrBoX 79787pJlYpARJiUFviZhge/zPI8MVOO63FPCB7o3jg3fDDxVOGoVszuqEZI3W3aJvZ7r ztPg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1679376008; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=Hlp+Ui1dMfarlEBa998LNtp9z3tMlr+TDoifOg7iOB0=; b=PHsqrEj3ePs8y1w4pL46mDwYum3OqFZ1fsPoeLfiy+jM1voaY0RM+lq9umPYautGsu fX33Ehpx7GmBJXitBIv2rpA/cheLrnMbzgxZ8IdLkY1XVGtK66GfhNHoFk3Iv+Ce67/C ahKx6Dfow4ZAy50QT8zd9nQ3lMzufZFuiQAIhzwveFsO6yJYZIxvT08SrAWMvlI4YABl JKnz6GSroPYFEq27gBeGDUvIKfpFIkI56jTIEIoMU9xerS/qSxNxdk8SL549QWa/6A7c UFf/2tcEVNB52S0FiaO6FVlDjdF6raW6Ehmi8v8rSa/ki8Dc7LZ2u+GogTfRGAkvfhV3 EQXw== X-Gm-Message-State: AO0yUKXxgOMzNTG1BUMsA2O7m7L3MCL8kZ3eAGL0aQw7WMeWinnbB7v9 MmymrUrux7AbuglircQEsVg= X-Google-Smtp-Source: AK7set+qPKN9FuFzi0+ho/Oz46zM1aUt7AJzT0xpeefodT65PkLrHCmd2c1uYjlALIiKw5T6Ynm/NA== X-Received: by 2002:a17:903:27cd:b0:1a1:d655:1ce4 with SMTP id km13-20020a17090327cd00b001a1d6551ce4mr831368plb.38.1679376008108; Mon, 20 Mar 2023 22:20:08 -0700 (PDT) Received: from dhcp-172-26-102-232.DHCP.thefacebook.com ([2620:10d:c090:400::5:1606]) by smtp.gmail.com with ESMTPSA id v16-20020a17090331d000b001a1ca65f434sm3757888ple.189.2023.03.20.22.20.06 (version=TLS1_3 cipher=TLS_CHACHA20_POLY1305_SHA256 bits=256/256); Mon, 20 Mar 2023 22:20:07 -0700 (PDT) From: Alexei Starovoitov To: davem@davemloft.net Cc: daniel@iogearbox.net, andrii@kernel.org, martin.lau@kernel.org, void@manifault.com, davemarchevsky@meta.com, tj@kernel.org, memxor@gmail.com, netdev@vger.kernel.org, bpf@vger.kernel.org, kernel-team@fb.com Subject: [PATCH bpf-next 3/4] libbpf: Support kfunc detection in light skeleton. Date: Mon, 20 Mar 2023 22:19:50 -0700 Message-Id: <20230321051951.58223-4-alexei.starovoitov@gmail.com> X-Mailer: git-send-email 2.37.1 (Apple Git-137.1) In-Reply-To: <20230321051951.58223-1-alexei.starovoitov@gmail.com> References: <20230321051951.58223-1-alexei.starovoitov@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net From: Alexei Starovoitov Teach gen_loader to find {btf_id, btf_obj_fd} of kernel variables and kfuncs and populate corresponding ld_imm64 and bpf_call insns. Signed-off-by: Alexei Starovoitov --- tools/lib/bpf/bpf_gen_internal.h | 4 +++- tools/lib/bpf/gen_loader.c | 38 ++++++++++++++++---------------- tools/lib/bpf/libbpf.c | 7 ++++-- 3 files changed, 27 insertions(+), 22 deletions(-) diff --git a/tools/lib/bpf/bpf_gen_internal.h b/tools/lib/bpf/bpf_gen_internal.h index 223308931d55..fdf44403ff36 100644 --- a/tools/lib/bpf/bpf_gen_internal.h +++ b/tools/lib/bpf/bpf_gen_internal.h @@ -11,6 +11,7 @@ struct ksym_relo_desc { int insn_idx; bool is_weak; bool is_typeless; + bool is_ld64; }; struct ksym_desc { @@ -24,6 +25,7 @@ struct ksym_desc { bool typeless; }; int insn; + bool is_ld64; }; struct bpf_gen { @@ -65,7 +67,7 @@ void bpf_gen__map_update_elem(struct bpf_gen *gen, int map_idx, void *value, __u void bpf_gen__map_freeze(struct bpf_gen *gen, int map_idx); void bpf_gen__record_attach_target(struct bpf_gen *gen, const char *name, enum bpf_attach_type type); void bpf_gen__record_extern(struct bpf_gen *gen, const char *name, bool is_weak, - bool is_typeless, int kind, int insn_idx); + bool is_typeless, bool is_ld64, int kind, int insn_idx); void bpf_gen__record_relo_core(struct bpf_gen *gen, const struct bpf_core_relo *core_relo); void bpf_gen__populate_outer_map(struct bpf_gen *gen, int outer_map_idx, int key, int inner_map_idx); diff --git a/tools/lib/bpf/gen_loader.c b/tools/lib/bpf/gen_loader.c index b74c82bb831e..83e8e3bfd8ff 100644 --- a/tools/lib/bpf/gen_loader.c +++ b/tools/lib/bpf/gen_loader.c @@ -560,7 +560,7 @@ static void emit_find_attach_target(struct bpf_gen *gen) } void bpf_gen__record_extern(struct bpf_gen *gen, const char *name, bool is_weak, - bool is_typeless, int kind, int insn_idx) + bool is_typeless, bool is_ld64, int kind, int insn_idx) { struct ksym_relo_desc *relo; @@ -574,6 +574,7 @@ void bpf_gen__record_extern(struct bpf_gen *gen, const char *name, bool is_weak, relo->name = name; relo->is_weak = is_weak; relo->is_typeless = is_typeless; + relo->is_ld64 = is_ld64; relo->kind = kind; relo->insn_idx = insn_idx; gen->relo_cnt++; @@ -586,9 +587,11 @@ static struct ksym_desc *get_ksym_desc(struct bpf_gen *gen, struct ksym_relo_des int i; for (i = 0; i < gen->nr_ksyms; i++) { - if (!strcmp(gen->ksyms[i].name, relo->name)) { - gen->ksyms[i].ref++; - return &gen->ksyms[i]; + kdesc = &gen->ksyms[i]; + if (kdesc->kind == relo->kind && kdesc->is_ld64 == relo->is_ld64 && + !strcmp(kdesc->name, relo->name)) { + kdesc->ref++; + return kdesc; } } kdesc = libbpf_reallocarray(gen->ksyms, gen->nr_ksyms + 1, sizeof(*kdesc)); @@ -603,6 +606,7 @@ static struct ksym_desc *get_ksym_desc(struct bpf_gen *gen, struct ksym_relo_des kdesc->ref = 1; kdesc->off = 0; kdesc->insn = 0; + kdesc->is_ld64 = relo->is_ld64; return kdesc; } @@ -864,23 +868,17 @@ static void emit_relo(struct bpf_gen *gen, struct ksym_relo_desc *relo, int insn { int insn; - pr_debug("gen: emit_relo (%d): %s at %d\n", relo->kind, relo->name, relo->insn_idx); + pr_debug("gen: emit_relo (%d): %s at %d %s\n", + relo->kind, relo->name, relo->insn_idx, relo->is_ld64 ? "ld64" : "call"); insn = insns + sizeof(struct bpf_insn) * relo->insn_idx; emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_8, BPF_PSEUDO_MAP_IDX_VALUE, 0, 0, 0, insn)); - switch (relo->kind) { - case BTF_KIND_VAR: + if (relo->is_ld64) { if (relo->is_typeless) emit_relo_ksym_typeless(gen, relo, insn); else emit_relo_ksym_btf(gen, relo, insn); - break; - case BTF_KIND_FUNC: + } else { emit_relo_kfunc_btf(gen, relo, insn); - break; - default: - pr_warn("Unknown relocation kind '%d'\n", relo->kind); - gen->error = -EDOM; - return; } } @@ -903,18 +901,20 @@ static void cleanup_core_relo(struct bpf_gen *gen) static void cleanup_relos(struct bpf_gen *gen, int insns) { + struct ksym_desc *kdesc; int i, insn; for (i = 0; i < gen->nr_ksyms; i++) { + kdesc = &gen->ksyms[i]; /* only close fds for typed ksyms and kfuncs */ - if (gen->ksyms[i].kind == BTF_KIND_VAR && !gen->ksyms[i].typeless) { + if (kdesc->is_ld64 && !kdesc->typeless) { /* close fd recorded in insn[insn_idx + 1].imm */ - insn = gen->ksyms[i].insn; + insn = kdesc->insn; insn += sizeof(struct bpf_insn) + offsetof(struct bpf_insn, imm); emit_sys_close_blob(gen, insn); - } else if (gen->ksyms[i].kind == BTF_KIND_FUNC) { - emit_sys_close_blob(gen, blob_fd_array_off(gen, gen->ksyms[i].off)); - if (gen->ksyms[i].off < MAX_FD_ARRAY_SZ) + } else if (!kdesc->is_ld64) { + emit_sys_close_blob(gen, blob_fd_array_off(gen, kdesc->off)); + if (kdesc->off < MAX_FD_ARRAY_SZ) gen->nr_fd_array--; } } diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index f8131f963803..5d32aa8ea38a 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -7070,18 +7070,21 @@ static int bpf_program_record_relos(struct bpf_program *prog) for (i = 0; i < prog->nr_reloc; i++) { struct reloc_desc *relo = &prog->reloc_desc[i]; struct extern_desc *ext = &obj->externs[relo->sym_off]; + int kind; switch (relo->type) { case RELO_EXTERN_LD64: if (ext->type != EXT_KSYM) continue; + kind = btf_is_var(btf__type_by_id(obj->btf, ext->btf_id)) ? + BTF_KIND_VAR : BTF_KIND_FUNC; bpf_gen__record_extern(obj->gen_loader, ext->name, ext->is_weak, !ext->ksym.type_id, - BTF_KIND_VAR, relo->insn_idx); + true, kind, relo->insn_idx); break; case RELO_EXTERN_CALL: bpf_gen__record_extern(obj->gen_loader, ext->name, - ext->is_weak, false, BTF_KIND_FUNC, + ext->is_weak, false, false, BTF_KIND_FUNC, relo->insn_idx); break; case RELO_CORE: { From patchwork Tue Mar 21 05:19:51 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexei Starovoitov X-Patchwork-Id: 13182264 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 68AA8C6FD1D for ; Tue, 21 Mar 2023 05:20:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230016AbjCUFUX (ORCPT ); Tue, 21 Mar 2023 01:20:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38348 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230025AbjCUFUQ (ORCPT ); Tue, 21 Mar 2023 01:20:16 -0400 Received: from mail-pl1-x62d.google.com (mail-pl1-x62d.google.com [IPv6:2607:f8b0:4864:20::62d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EABD739BB4; Mon, 20 Mar 2023 22:20:12 -0700 (PDT) Received: by mail-pl1-x62d.google.com with SMTP id w4so6833557plg.9; Mon, 20 Mar 2023 22:20:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; t=1679376012; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=N2/BbxURZuhrKG/WKWH04ora8blM9R4u1zRqb6oG8i4=; b=V5HCzoo5OlsjaLCMadkcHew3Zw1YqEri3mM2XPpb1EVAhet8blJ9GzhaezxHCCL/um yyLkbSyYW8KlzSd/ZLYvmBR2rIB97GePyl/SsOQYnklQ+/udEqGegXMmmFFKzRMzWu6+ XiAfZSfKZnhvylz71Zg1O42XmbpheRdUtHVBU8zVYHaz6lo1KWaNuOdO+fBD79X/5xfG xdq2d0iHh3hgn/8zvIGCPOWz6bUrtbQiiuJDrKStsPenpCpV4QJXQZWZBdp2pOVcpnuu Fb2JQ7ZtxCSUV6ySTwqqzlNol8m3c1I1tot8g1wiSuVbK5dcdWB8oab0oMxTt0wgwu0Z aK6A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1679376012; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=N2/BbxURZuhrKG/WKWH04ora8blM9R4u1zRqb6oG8i4=; b=iabSQQMqH/AEOlsU+BBIqz0qU5SgVA1r2vPIjGY78JZkmnhu7/lBseR/NEle7u47EC WAK6p1TF6/9FwyGU/hxDnQwE9oSe/ApKbcA7vcAbXz0tYSBdxuMDCZff/7jMfEi6o8vH TZlMr2BJcnIe4m8o4MkJpcTUQfhM1Ovh28/KOCqrEHdEQXdJPWnl56Lj2itsqr68hUiI xVYMoQNi5CMTm3emW/004vtY4Ew3t34dMCbwedKIC7FIT3WYU2C+yjqgaqYInDTNDcH6 MbJiNrkrTivNU5kQeo5QvNAGImtC0CAfLXpViI8jYggD8YjhxEuN9Pd74bhhBh3PJwB/ kg+Q== X-Gm-Message-State: AO0yUKVc6yFwfmWZ9cG/ebPdB/VvxYLnV4VzRjf5CcuB1JN3hyKF3AKn 6BVqS/FLFJnK7l+JCIslBuE= X-Google-Smtp-Source: AK7set/BipvYLMOB+yrbFBHjiyfDVVEkV5UuJ38qxAeanQ4KGd5a/NRlng2fHdYouwAtXghhzxGUjg== X-Received: by 2002:a17:90b:3846:b0:23d:4e0e:cf34 with SMTP id nl6-20020a17090b384600b0023d4e0ecf34mr1408526pjb.34.1679376012207; Mon, 20 Mar 2023 22:20:12 -0700 (PDT) Received: from dhcp-172-26-102-232.DHCP.thefacebook.com ([2620:10d:c090:400::5:1606]) by smtp.gmail.com with ESMTPSA id h14-20020a17090acf0e00b0023fda235bb5sm1042900pju.33.2023.03.20.22.20.10 (version=TLS1_3 cipher=TLS_CHACHA20_POLY1305_SHA256 bits=256/256); Mon, 20 Mar 2023 22:20:11 -0700 (PDT) From: Alexei Starovoitov To: davem@davemloft.net Cc: daniel@iogearbox.net, andrii@kernel.org, martin.lau@kernel.org, void@manifault.com, davemarchevsky@meta.com, tj@kernel.org, memxor@gmail.com, netdev@vger.kernel.org, bpf@vger.kernel.org, kernel-team@fb.com Subject: [PATCH bpf-next 4/4] selftests/bpf: Add light skeleton test for kfunc detection. Date: Mon, 20 Mar 2023 22:19:51 -0700 Message-Id: <20230321051951.58223-5-alexei.starovoitov@gmail.com> X-Mailer: git-send-email 2.37.1 (Apple Git-137.1) In-Reply-To: <20230321051951.58223-1-alexei.starovoitov@gmail.com> References: <20230321051951.58223-1-alexei.starovoitov@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net From: Alexei Starovoitov Add light skeleton test for kfunc detection. Signed-off-by: Alexei Starovoitov --- .../testing/selftests/bpf/progs/test_ksyms_weak.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/tools/testing/selftests/bpf/progs/test_ksyms_weak.c b/tools/testing/selftests/bpf/progs/test_ksyms_weak.c index 7003eef0c192..d00268c91e19 100644 --- a/tools/testing/selftests/bpf/progs/test_ksyms_weak.c +++ b/tools/testing/selftests/bpf/progs/test_ksyms_weak.c @@ -20,6 +20,8 @@ __u64 out__non_existent_typed = -1; /* test existing weak symbols can be resolved. */ extern const struct rq runqueues __ksym __weak; /* typed */ extern const void bpf_prog_active __ksym __weak; /* typeless */ +struct task_struct *bpf_task_acquire(struct task_struct *p) __ksym __weak; +void bpf_testmod_test_mod_kfunc(int i) __ksym __weak; /* non-existent weak symbols. */ @@ -29,6 +31,7 @@ extern const void bpf_link_fops1 __ksym __weak; /* typed symbols, default to zero. */ extern const int bpf_link_fops2 __ksym __weak; +void invalid_kfunc(void) __ksym __weak; SEC("raw_tp/sys_enter") int pass_handler(const void *ctx) @@ -50,6 +53,18 @@ int pass_handler(const void *ctx) if (&bpf_link_fops2) /* can't happen */ out__non_existent_typed = (__u64)bpf_per_cpu_ptr(&bpf_link_fops2, 0); + if (!bpf_ksym_exists(bpf_task_acquire)) + /* dead code won't be seen by the verifier */ + bpf_task_acquire(0); + + if (!bpf_ksym_exists(bpf_testmod_test_mod_kfunc)) + /* dead code won't be seen by the verifier */ + bpf_testmod_test_mod_kfunc(0); + + if (bpf_ksym_exists(invalid_kfunc)) + /* dead code won't be seen by the verifier */ + invalid_kfunc(); + return 0; }