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 0BA7EE81E0D for ; Fri, 6 Oct 2023 15:45:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232446AbjJFPpH (ORCPT ); Fri, 6 Oct 2023 11:45:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39928 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229853AbjJFPpG (ORCPT ); Fri, 6 Oct 2023 11:45:06 -0400 Received: from mail-ej1-f50.google.com (mail-ej1-f50.google.com [209.85.218.50]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2CE7CAD; Fri, 6 Oct 2023 08:45:05 -0700 (PDT) Received: by mail-ej1-f50.google.com with SMTP id a640c23a62f3a-9936b3d0286so420992966b.0; Fri, 06 Oct 2023 08:45:05 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1696607103; x=1697211903; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=8aFYMnezX6QVt6CPqUMIG1km0ffIJ/7lCOUbibCVNYY=; b=cr27A3mZjcwN/2wRLR+iWgqsHOq9hJfamtEh/LuSr5A/xOgRWm8TP6XNjksmYUYaPe iSRDwHgcZNRezDU298WX/3B0TDH93SRW4Uag4RCAJSabwftxLSUdk8Dio4Dn+62XGjHi X+FNQYCY7SyUCTM9OYiln8SJOT9TBV0HdKoGPZCfuLuWXSJgV9LNsYOZa617a6nV7CD3 fuuKHx5izEtDeyQfnlFXy0JUSojtQ/IH8AYGsh5hLp3wNtgmeOIzVhpyEmKWFdzsDm9P wr0TIfmZr27gf/E5vSdNzwQ/OLk2khzk4kw672nYksamgKDzMeXpVWcslwd/DPVS1ldP pYRg== X-Gm-Message-State: AOJu0Yzc2U4YqMa1COiPHr6dbW+smLkYeJRHrB0LYI0DH+dEJHa9X/Fv drANEtfxm21zK8x/SrfvbJg= X-Google-Smtp-Source: AGHT+IE9DXNEm/MJhfpSSluc6f57Rm80AeOvy49rpEIS7UOG3ALQ+Sr77GzdCmsCicO59TMC1q98SQ== X-Received: by 2002:a17:906:9c1:b0:9ae:5aa4:9fa with SMTP id r1-20020a17090609c100b009ae5aa409famr7685330eje.42.1696607103107; Fri, 06 Oct 2023 08:45:03 -0700 (PDT) Received: from gmail.com (fwdproxy-cln-117.fbsv.net. [2a03:2880:31ff:75::face:b00c]) by smtp.gmail.com with ESMTPSA id jw26-20020a17090776ba00b009ae3d711fd9sm3040104ejc.69.2023.10.06.08.45.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 06 Oct 2023 08:45:02 -0700 (PDT) Date: Fri, 6 Oct 2023 08:45:00 -0700 From: Breno Leitao To: Jakub Kicinski Cc: sdf@google.com, axboe@kernel.dk, asml.silence@gmail.com, willemdebruijn.kernel@gmail.com, martin.lau@linux.dev, krisman@suse.de, bpf@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, io-uring@vger.kernel.org, pabeni@redhat.com Subject: Re: [PATCH v4 00/10] io_uring: Initial support for {s,g}etsockopt commands Message-ID: References: <20230904162504.1356068-1-leitao@debian.org> <20230905154951.0d0d3962@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230905154951.0d0d3962@kernel.org> Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Hello Jakub, On Tue, Sep 05, 2023 at 03:49:51PM -0700, Jakub Kicinski wrote: > On Mon, 4 Sep 2023 09:24:53 -0700 Breno Leitao wrote: > > Patches 1-2: Modify the BPF hooks to support sockptr_t, so, these functions > > become flexible enough to accept user or kernel pointers for optval/optlen. > > Have you seen: > > https://lore.kernel.org/all/CAHk-=wgGV61xrG=gO0=dXH64o2TDWWrXn1mx-CX885JZ7h84Og@mail.gmail.com/ > > ? I wasn't aware that Linus felt this way, now I wonder if having > sockptr_t spread will raise any red flags as this code flows back > to him. Thanks for the heads-up. I've been thinking about it for a while and I'd like to hear what are the next steps here. Let me first back up and state where we are, and what is the current situation: 1) __sys_getsockopt() uses __user pointers for both optval and optlen 2) For io_uring command, Jens[1] suggested we get optlen from the io_uring sqe, which is a kernel pointer/value. Thus, we need to make the common code (callbacks) able to handle __user and kernel pointers (for optlen, at least). >From a proto_ops callback perspective, ->setsockopt() uses sockptr. int (*setsockopt)(struct socket *sock, int level, int optname, sockptr_t optval, unsigned int optlen); Getsockopt() uses sockptr() for level=SOL_SOCKET: int sk_getsockopt(struct sock *sk, int level, int optname, sockptr_t optval, sockptr_t optlen) But not for the other levels: int (*getsockopt)(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen); That said, if this patchset shouldn't use sockptr anymore, what is the recommendation? If we move this patchset to use iov_iter instead of sockptr, then I understand we want to move *all* these callbacks to use iov_vec. Is this the right direction? Thanks for the guidance! [1] https://lore.kernel.org/all/efe602f1-8e72-466c-b796-0083fd1c6d82@kernel.dk/