From patchwork Wed Jan 25 05:03:56 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Vernet X-Patchwork-Id: 13115003 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 19D98C54E94 for ; Wed, 25 Jan 2023 05:04:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233949AbjAYFEO (ORCPT ); Wed, 25 Jan 2023 00:04:14 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45112 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232745AbjAYFEM (ORCPT ); Wed, 25 Jan 2023 00:04:12 -0500 Received: from mail-pl1-f171.google.com (mail-pl1-f171.google.com [209.85.214.171]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 23FFA474F4; Tue, 24 Jan 2023 21:04:09 -0800 (PST) Received: by mail-pl1-f171.google.com with SMTP id d9so16832255pll.9; Tue, 24 Jan 2023 21:04:09 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; 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=geJZ0n/Osgu93pxX9vL5o3+bzLvg1dQW9V/BZwV5zXs=; b=SdK8le0Oc3RV2VGyiqC5X5/c8O3ivrOV9JuDGc5CCgChhAgTX/kU4ADFuksHJMoHHo uZn16fni36zg9024Cfg+IxHK/itIi+Nj99WUA/neTRaZHTIALixkhuxtfgWwe+wOgtHu zQ0v+J6j6rbmCYwWnlNXLHrbDeYW6LAooJuTibHDMvGUXZQ25ix9CS2SH16G8OHuW3jT 6shwAJQ0apAbMqIaJLDPBkcnv24MmRr+7DXqL59pCeWFnscjt5OjP8NbKl8hDISzGjXi 4mpQ5xIrcdv7H8CVUQEr+eE/kc+Z6XsUXH9qOzsGPMTx3Ftnum60YVnLms+WEMWinfui LcBQ== X-Gm-Message-State: AFqh2kqsCgzIfDQ86gD8UMUkxxaXyf12qfwQe6I3cpYdihiHt1Iy53mc tdN+GFJtbB1JTjclYfOa3fXwAoW1qrsQ2IXN X-Google-Smtp-Source: AMrXdXv2QGb+DYsRsUdI31UA6j8j3Zb8Trb48OlYak4YArgfl449oDIC4xUqhzNHCwYwQIgZFZFRWA== X-Received: by 2002:a05:6a20:c120:b0:b8:8027:13a5 with SMTP id bh32-20020a056a20c12000b000b8802713a5mr31697542pzb.33.1674623048109; Tue, 24 Jan 2023 21:04:08 -0800 (PST) Received: from localhost ([2620:10d:c090:400::5:d24a]) by smtp.gmail.com with ESMTPSA id u71-20020a63794a000000b004d346876d37sm2301166pgc.45.2023.01.24.21.04.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 24 Jan 2023 21:04:07 -0800 (PST) From: David Vernet To: bpf@vger.kernel.org Cc: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, martin.lau@linux.dev, song@kernel.org, yhs@meta.com, john.fastabend@gmail.com, kpsingh@kernel.org, sdf@google.com, haoluo@google.com, jolsa@kernel.org, linux-kernel@vger.kernel.org, kernel-team@meta.com, tj@kernel.org Subject: [PATCH bpf-next v3 1/4] bpf: Allow BPF_PROG_TYPE_STRUCT_OPS programs to be sleepable Date: Tue, 24 Jan 2023 23:03:56 -0600 Message-Id: <20230125050359.339273-2-void@manifault.com> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230125050359.339273-1-void@manifault.com> References: <20230125050359.339273-1-void@manifault.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net BPF struct_ops programs currently cannot be marked as sleepable. This need not be the case -- struct_ops programs can be sleepable, and e.g. invoke kfuncs that export the KF_SLEEPABLE flag. So as to allow future struct_ops programs to invoke such kfuncs, this patch updates the verifier to allow struct_ops programs to be sleepable. A follow-on patch will add support to libbpf for specifying struct_ops.s as a sleepable struct_ops program, and then another patch will add testcases to the dummy_st_ops selftest suite which test sleepable struct_ops behavior. Signed-off-by: David Vernet --- kernel/bpf/verifier.c | 5 +++-- tools/testing/selftests/bpf/verifier/sleepable.c | 2 +- 2 files changed, 4 insertions(+), 3 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 800488289297..2b8f0c0aa0cc 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -17054,7 +17054,8 @@ static bool can_be_sleepable(struct bpf_prog *prog) } } return prog->type == BPF_PROG_TYPE_LSM || - prog->type == BPF_PROG_TYPE_KPROBE; /* only for uprobes */ + prog->type == BPF_PROG_TYPE_KPROBE /* only for uprobes */ || + prog->type == BPF_PROG_TYPE_STRUCT_OPS; } static int check_attach_btf_id(struct bpf_verifier_env *env) @@ -17076,7 +17077,7 @@ static int check_attach_btf_id(struct bpf_verifier_env *env) } if (prog->aux->sleepable && !can_be_sleepable(prog)) { - verbose(env, "Only fentry/fexit/fmod_ret, lsm, iter and uprobe programs can be sleepable\n"); + verbose(env, "Only fentry/fexit/fmod_ret, lsm, iter, uprobe, and struct_ops programs can be sleepable\n"); return -EINVAL; } diff --git a/tools/testing/selftests/bpf/verifier/sleepable.c b/tools/testing/selftests/bpf/verifier/sleepable.c index bea0daef908a..1f0d2bdc673f 100644 --- a/tools/testing/selftests/bpf/verifier/sleepable.c +++ b/tools/testing/selftests/bpf/verifier/sleepable.c @@ -85,7 +85,7 @@ .expected_attach_type = BPF_TRACE_RAW_TP, .kfunc = "sched_switch", .result = REJECT, - .errstr = "Only fentry/fexit/fmod_ret, lsm, iter and uprobe programs can be sleepable", + .errstr = "Only fentry/fexit/fmod_ret, lsm, iter, uprobe, and struct_ops programs can be sleepable", .flags = BPF_F_SLEEPABLE, .runs = -1, },