From mboxrd@z Thu Jan 1 00:00:00 1970 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 73E62C4332F for ; Wed, 14 Dec 2022 10:42:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229464AbiLNKmg (ORCPT ); Wed, 14 Dec 2022 05:42:36 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52136 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229660AbiLNKme (ORCPT ); Wed, 14 Dec 2022 05:42:34 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F0D8D23392 for ; Wed, 14 Dec 2022 02:41:56 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1671014516; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=0wdWsTQy1PmtZVWiiL7HDvu5DGURuGqGghZsLS7DEOc=; b=H04frUGOxCnKcDvmB8Z58y3MKmxvFmr3HAH1hMDTDGm5l/U4hxf0SbKews2jZJrZ8+vAbX sdBVU/UJknRCp6t1PsWAIybk5bSDSA9BpDbsythZ9uMRnnsDNODbMirmS8gBoDZ2RN6z/g DcT2av+vGmIIB7+e6cFnum+dvqDko9A= Received: from mail-ed1-f71.google.com (mail-ed1-f71.google.com [209.85.208.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_128_GCM_SHA256) id us-mta-580-UIIwOxOKNPSLNGDQEP-vzg-1; Wed, 14 Dec 2022 05:41:54 -0500 X-MC-Unique: UIIwOxOKNPSLNGDQEP-vzg-1 Received: by mail-ed1-f71.google.com with SMTP id h8-20020a056402280800b0046af59e0986so9401427ede.22 for ; Wed, 14 Dec 2022 02:41:54 -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:message-id:date:references :in-reply-to:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=0wdWsTQy1PmtZVWiiL7HDvu5DGURuGqGghZsLS7DEOc=; b=TZ1IF3iWanVhaBzpOijKKyRlgl3NvHT0pHoXSEN6qiFTQnn0QNyrqxL6c6dZY/LlID GTGGA10G8woRetIdFU2swdCKEO/fTm65Ba7wXsSs2C4IU1N4K6f9CaHJO4kwU9O8igQL 8Oeaz5Xaok7DWhiNEDk2pQVPgIGKGtiQwKeWHjb3QlGqwqxgn7bHkRYUzCUql14ivaY+ JdbSfxmlpp4kSomRw3cB2VpdFurg8QxNujjIm1ebyfmXHlsjvQOpYD3udrXbtbC9XhL1 U1KV3OLWJE5KzI4vLA3KCe9lo4YynusgW8HZpE1uzE9BFB5ylsi9eEdY3O5Wa88qlgPG ua5A== X-Gm-Message-State: ANoB5plbg+NKukkilDndZZ44LAOsC2DYw1vSAlf6VKPbZpOlL3AGH8NC 28TIbHK715sMmZ3FH9yOO9bH2Df6wjVrKzFItw+Cxrz1HFvSSmx5nmZX/3sjk4pjZShRoCSJ7ZR NIqwHNtIbeUXd X-Received: by 2002:a17:906:6ad7:b0:7c1:ac8:399 with SMTP id q23-20020a1709066ad700b007c10ac80399mr5278355ejs.55.1671014513764; Wed, 14 Dec 2022 02:41:53 -0800 (PST) X-Google-Smtp-Source: AA0mqf5k98PrAYSt8YBPsktotuBlZ4RsT1r4m5dQQWi2PWynxz6//xez8PWUS6/4F7JYmq7UbD0Aag== X-Received: by 2002:a17:906:6ad7:b0:7c1:ac8:399 with SMTP id q23-20020a1709066ad700b007c10ac80399mr5278335ejs.55.1671014513471; Wed, 14 Dec 2022 02:41:53 -0800 (PST) Received: from alrua-x1.borgediget.toke.dk ([45.145.92.2]) by smtp.gmail.com with ESMTPSA id kz21-20020a17090777d500b007c0c91eae04sm5661630ejc.151.2022.12.14.02.41.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 14 Dec 2022 02:41:52 -0800 (PST) Received: by alrua-x1.borgediget.toke.dk (Postfix, from userid 1000) id F3C1082F53C; Wed, 14 Dec 2022 11:41:51 +0100 (CET) From: Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= To: Martin KaFai Lau , Stanislav Fomichev Cc: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, song@kernel.org, yhs@fb.com, john.fastabend@gmail.com, kpsingh@kernel.org, haoluo@google.com, jolsa@kernel.org, bpf@vger.kernel.org Subject: Re: [PATCH bpf-next v4 06/15] bpf: Support consuming XDP HW metadata from fext programs In-Reply-To: <1a0436c5-2198-0c69-1306-872454d2fb13@linux.dev> References: <20221213023605.737383-1-sdf@google.com> <20221213023605.737383-7-sdf@google.com> <1a0436c5-2198-0c69-1306-872454d2fb13@linux.dev> X-Clacks-Overhead: GNU Terry Pratchett Date: Wed, 14 Dec 2022 11:41:51 +0100 Message-ID: <87cz8mgtcg.fsf@toke.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Martin KaFai Lau writes: > On 12/12/22 6:35 PM, Stanislav Fomichev wrote: >> From: Toke H=C3=B8iland-J=C3=B8rgensen >>=20 >> Instead of rejecting the attaching of PROG_TYPE_EXT programs to XDP >> programs that consume HW metadata, implement support for propagating the >> offload information. The extension program doesn't need to set a flag or >> ifindex, it these will just be propagated from the target by the verifie= r. > > s/it/because/ ... these will just be propagated.... Yeah, or just drop 'it' :) >> We need to create a separate offload object for the extension program, >> though, since it can be reattached to a different program later (which >> means we can't just inhering the offload information from the target). > > hmm.... inheriting? Think I meant to write "we can't just inherit" >> diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c >> index 11c558be4992..8686475f0dbe 100644 >> --- a/kernel/bpf/syscall.c >> +++ b/kernel/bpf/syscall.c >> @@ -3021,6 +3021,14 @@ static int bpf_tracing_prog_attach(struct bpf_pro= g *prog, >> goto out_put_prog; >> } >>=20=20=20 >> + if (bpf_prog_is_dev_bound(prog->aux) && > > >> + (bpf_prog_is_offloaded(tgt_prog->aux) || >> + !bpf_prog_is_dev_bound(tgt_prog->aux) || >> + !bpf_offload_dev_match(prog, tgt_prog->aux->offload->netdev))) { > > hmm... tgt_prog->aux->offload does not look safe without taking bpf_devs_= lock.=20 > offload could be NULL, no? > > It probably needs a bpf_prog_dev_bound_match(prog, tgt_prog) which takes = the lock. Hmm, right, I was kinda expecting that this would not go away while tgt_prog was alive, but I see now that's not the case due to the unregister hook. So yeah, needs locking (same below) :) -Toke