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 X-Spam-Level: X-Spam-Status: No, score=-0.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EF2BAC3A5A6 for ; Mon, 26 Aug 2019 17:57:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C65C720850 for ; Mon, 26 Aug 2019 17:57:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Y4LKMB58" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387558AbfHZR54 (ORCPT ); Mon, 26 Aug 2019 13:57:56 -0400 Received: from mail-pl1-f196.google.com ([209.85.214.196]:36607 "EHLO mail-pl1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728280AbfHZR54 (ORCPT ); Mon, 26 Aug 2019 13:57:56 -0400 Received: by mail-pl1-f196.google.com with SMTP id f19so10396085plr.3; Mon, 26 Aug 2019 10:57:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=77MKV+MJ6zyFv67aHlgM/8m5X/mM7/TRqBSqvmlPQ9E=; b=Y4LKMB58TZntJjF5waqJp99gc/Rrj1YMoljV8x/GPkoGUPWWGy7MNl/75XFg70JRnJ 1EIJKSBZQBFMWwT7zg50Y184kStpCGluR9PQ39mpDSSSPqRGwhj29M0IRlTgjxEHfaja rV+/QCbFOsrKZsz6fQXF6rlQXYnoleOfejCb8ITVunH7tRXm8Aq9Ertfdk1jT3R2jr29 wAg3CcYAdztk8isu4TQM9WQ69AKUxQmUuTz5nuy+KwgzBCmppJI2q3+bem8wq8Rlp7OX vyrmoh2bcvklCwB/EVzfxNaXnrcvff5hcMmmxX1eNbe42rGuDrm58p3wR4CYI7oHSUjl /xaQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=77MKV+MJ6zyFv67aHlgM/8m5X/mM7/TRqBSqvmlPQ9E=; b=OvfoGTdgb7gVOVm5JpFiOCrqmNU2/JQT22KsRFc121FVdWjxzlu98+UIJD3X+ltD9n lAkg7gnOCy6TUjIQDIFVoQipwu0SwKqNt5hxgnu2iMKTlbN8OAFkRuWZyD/gIkTK+TcP 7CCqWvUmqln6q4YD9sFJ40EU112PYK8hqC5vE1FsabYQD3jslRc2cBzQhUoC7UUg/mo1 v30toYU9U5+tnq/JIAJp97FsUZm1uydVSJz9AMmyEbj0PxvuiA1hZuXvHOV9FPgqMBzm bHV9Jx5eOlTn4o4vF9dKz3vN+3kl5I10OfUUwP/Bk4vZIKiRPieOEV5C/MZl87CCX6Dr vsYA== X-Gm-Message-State: APjAAAUSLcG20duji/kHd+htMlk+GBITZ4xC4ZaxEfrilG7gNOFNwnFw YtZnBt8GXRxizyhOwtFsU9U= X-Google-Smtp-Source: APXvYqz/wQlGKHGkT3JOvNWRfTMmGAHixD/68vdDO+oS2Lw+jc4kYYu2NfkV4Tx3YqVDRBHBQkbnww== X-Received: by 2002:a17:902:b40c:: with SMTP id x12mr20189459plr.81.1566842275349; Mon, 26 Aug 2019 10:57:55 -0700 (PDT) Received: from [172.20.53.188] ([2620:10d:c090:200::3:2982]) by smtp.gmail.com with ESMTPSA id q13sm20741362pfl.124.2019.08.26.10.57.54 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 26 Aug 2019 10:57:54 -0700 (PDT) From: "Jonathan Lemon" To: "=?utf-8?b?QmrDtnJuIFTDtnBlbA==?=" Cc: "Ilya Maximets" , "=?utf-8?b?QmrDtnJuIFTDtnBlbA==?=" , ast@kernel.org, daniel@iogearbox.net, netdev@vger.kernel.org, magnus.karlsson@intel.com, magnus.karlsson@gmail.com, bpf@vger.kernel.org, syzbot+c82697e3043781e08802@syzkaller.appspotmail.com, hdanton@sina.com Subject: Re: [PATCH bpf-next v2 2/4] xsk: add proper barriers and {READ, WRITE}_ONCE-correctness for state Date: Mon, 26 Aug 2019 10:57:53 -0700 X-Mailer: MailMate (1.12.5r5635) Message-ID: <3F33CA61-D000-4318-958D-90F5A3CCAD60@gmail.com> In-Reply-To: <1b780dd4-227f-64c4-260d-9e819ba7081f@intel.com> References: <20190826061053.15996-1-bjorn.topel@gmail.com> <20190826061053.15996-3-bjorn.topel@gmail.com> <14576fd3-69ce-6493-5a38-c47566851d4e@samsung.com> <1b780dd4-227f-64c4-260d-9e819ba7081f@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 26 Aug 2019, at 9:34, Björn Töpel wrote: > On 2019-08-26 17:24, Ilya Maximets wrote: >> This changes the error code a bit. >> Previously: >> umem exists + xs unbound --> EINVAL >> no umem + xs unbound --> EBADF >> xs bound to different dev/q --> EINVAL >> >> With this change: >> umem exists + xs unbound --> EBADF >> no umem + xs unbound --> EBADF >> xs bound to different dev/q --> EINVAL >> >> Just a note. Not sure if this is important. >> > > Note that this is for *shared* umem, so it's very seldom used. Still, > you're right, that strictly this is an uapi break, but I'd vote for the > change still. I find it hard to see that anyone relies on EINVAL/EBADF > for shared umem bind. > > Opinions? :-) I'd agree - if it isn't documented somewhere, it's not an API break. :) -- Jonathan