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 AD4CAC4167E for ; Tue, 15 Nov 2022 23:15:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229829AbiKOXPY (ORCPT ); Tue, 15 Nov 2022 18:15:24 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58432 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232211AbiKOXO6 (ORCPT ); Tue, 15 Nov 2022 18:14:58 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CFEFFF02 for ; Tue, 15 Nov 2022 15:14:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1668554046; 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=/HeSwBts+JSgnN4qNzSCdOMxQO+gGwYD3f5ouvjaYqA=; b=IFC4+PoSrVqEetQoCxj9Cn5lvgkbFSCSQRyNUH3oY4HrzYpsUO9cd2xxI0GlkmBauEtT8j Tec7oiVm+qxdkcxgKwrabctrbj3SKtwmSnJvpnuOi6RT+lygeJ4IXxO1/tL7+NnTYDbOzZ JtHL24mUGEv5IfVvtQe3NdZjL7HRqgM= Received: from mail-ed1-f70.google.com (mail-ed1-f70.google.com [209.85.208.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_128_GCM_SHA256) id us-mta-369-XzsZW5W3PAix8iZEs5-tZQ-1; Tue, 15 Nov 2022 18:14:04 -0500 X-MC-Unique: XzsZW5W3PAix8iZEs5-tZQ-1 Received: by mail-ed1-f70.google.com with SMTP id y18-20020a056402359200b004635f8b1bfbso11046310edc.17 for ; Tue, 15 Nov 2022 15:14:04 -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=/HeSwBts+JSgnN4qNzSCdOMxQO+gGwYD3f5ouvjaYqA=; b=l6s6pV8ffogIMif/An1vXB3v0FcTmJ6tMN2QkYlhXOq8wEIkxcA/HgsmNEJ9YK+WFl yfA3PQ3QZgxTpCH/E9V2fNQsKTyO3JVddY+UPTCjtmANPWge9RYmEqM0hb0nRx7DJaeQ A7YKU2Eh22VOmK9B3OnM3Da+f1EU+yCgaQo484THN0DpGR5ZsyB4/Y6p0ynsbThNUlOS VfUtL2jzc4IvNW9e0WeHmAMm0afwLGhpqcjekKPxMnyxiFlAMzARSxkMeZLVbbdT9vxj wbGsoIHLGRYR6L/VJ4toQ7fMqwaR12oC3ddTqiLF+PxdUokXU7yBp4dO5DnBXD3df4/4 yvqg== X-Gm-Message-State: ANoB5pkNcnhMjskvZb/qW0Jez9CxXaN/rQsh9izShaq2IbW1JAKQJy+w wymPhTNmmncEGqLF7fs3pKhJd4BgcDmwHZXwbE7wdj35SjZbcDW3Q/Aqu7A6A4utLuMjze4XjCg TUhL7pMpuIX5P X-Received: by 2002:a05:6402:b50:b0:459:2b41:3922 with SMTP id bx16-20020a0564020b5000b004592b413922mr16560725edb.160.1668554042072; Tue, 15 Nov 2022 15:14:02 -0800 (PST) X-Google-Smtp-Source: AA0mqf7pl/gGMle47sfiL6lZ912AHH0UDHMN2Q/n0F8Q3WYCaLSOvQx4KjSEf3L5DPcBEHTJXR2z2A== X-Received: by 2002:a05:6402:b50:b0:459:2b41:3922 with SMTP id bx16-20020a0564020b5000b004592b413922mr16560671edb.160.1668554041139; Tue, 15 Nov 2022 15:14:01 -0800 (PST) Received: from alrua-x1.borgediget.toke.dk ([2a0c:4d80:42:443::2]) by smtp.gmail.com with ESMTPSA id y14-20020aa7ccce000000b0045b4b67156fsm6759985edt.45.2022.11.15.15.14.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 15 Nov 2022 15:14:00 -0800 (PST) Received: by alrua-x1.borgediget.toke.dk (Postfix, from userid 1000) id 7AE7E7A6D67; Wed, 16 Nov 2022 00:13:59 +0100 (CET) From: Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= To: Alexei Starovoitov , Stanislav Fomichev Cc: bpf , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Hao Luo , Jiri Olsa , David Ahern , Jakub Kicinski , Willem de Bruijn , Jesper Dangaard Brouer , Anatoly Burakov , Alexander Lobakin , Magnus Karlsson , Maryam Tahhan , xdp-hints@xdp-project.net, Network Development Subject: Re: [xdp-hints] Re: [PATCH bpf-next 00/11] xdp: hints via kfuncs In-Reply-To: References: <20221115030210.3159213-1-sdf@google.com> <87mt8si56i.fsf@toke.dk> X-Clacks-Overhead: GNU Terry Pratchett Date: Wed, 16 Nov 2022 00:13:59 +0100 Message-ID: <87zgcrdd54.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 Alexei Starovoitov writes: > On Tue, Nov 15, 2022 at 10:38 AM Stanislav Fomichev wrot= e: >> >> On Tue, Nov 15, 2022 at 7:54 AM Toke H=C3=B8iland-J=C3=B8rgensen wrote: >> > >> > Stanislav Fomichev writes: >> > >> > > - drop __randomize_layout >> > > >> > > Not sure it's possible to sanely expose it via UAPI. Because every >> > > .o potentially gets its own randomized layout, test_progs >> > > refuses to link. >> > >> > So this won't work if the struct is in a kernel-supplied UAPI header >> > (which would include the __randomize_layout tag). But if it's *not* in= a >> > UAPI header it should still be included in a stable form (i.e., without >> > the randomize tag) in vmlinux.h, right? Which would be the point: >> > consumers would be forced to read it from there and do CO-RE on it... >> >> So you're suggesting something like the following in the uapi header? >> >> #ifndef __KERNEL__ >> #define __randomize_layout >> #endif >> > > 1. > __randomize_layout in uapi header makes no sense. I agree, which is why I wanted it to be only in vmlinux.h... > 2. > It's supported by gcc plugin and afaik that plugin is broken > vs debug info, so dwarf is broken, hence BTF is broken too, > and CO-RE doesn't work on kernels compiled with that gcc plugin. ...however this one seems a deal breaker. Ah well, too bad, seemed like a neat trick to enforce CO-RE :( -Toke