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=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, 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 99FFBC43603 for ; Tue, 10 Dec 2019 00:18:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6A0FC2080D for ; Tue, 10 Dec 2019 00:18:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=netronome-com.20150623.gappssmtp.com header.i=@netronome-com.20150623.gappssmtp.com header.b="xOuetOzK" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727317AbfLJASk (ORCPT ); Mon, 9 Dec 2019 19:18:40 -0500 Received: from mail-pf1-f196.google.com ([209.85.210.196]:46727 "EHLO mail-pf1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726495AbfLJASj (ORCPT ); Mon, 9 Dec 2019 19:18:39 -0500 Received: by mail-pf1-f196.google.com with SMTP id y14so8068522pfm.13 for ; Mon, 09 Dec 2019 16:18:39 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=netronome-com.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:in-reply-to:references :organization:mime-version:content-transfer-encoding; bh=yR1KySs+qQP0dJ1gc6Y3Ylu4ra2zW/p9kEKFua+/qu4=; b=xOuetOzK7jpTSuWGsrj82iBN1wkwIE05VOzQMi0hYWSu4Dt5qQz9XcWGfZdST7Iuwv y4caUubRi6zNGl53A9zz0NW2Ci7JjVSPIDKm5YRtt4eFvz828uriCkDxXz04R97bdGuT olnJ7OGNyWhguJi2GQHYcYG9Ebbu2342pgGfAamLA9nhmcn9J0dHpBy69JV8YNExxwfh sNcZVTT9rZnhds1mR0m2GU4g3KHaun1ODmJfAPwm0Ou/469ZawwNSjxLi6uU6wjR9pzz b8349jQEmIxobfOkB+el7XJVdfWjF47LUc5c+urTxhGlSK47JqfBkvL5KL3nZXOgwrTQ F8qg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:organization:mime-version:content-transfer-encoding; bh=yR1KySs+qQP0dJ1gc6Y3Ylu4ra2zW/p9kEKFua+/qu4=; b=MMgEwfFfzbZZn35gdSusDFRleM9A7g+ZJ3PONwiW/Tw6WL0TSZMh7jpzotXFetstef IWlwodiFYh5IWcQsGYhPltwHBm1PNxqEV6+w9SqNAo+V52U4iCZFanqnVDep65tVglRd ryYluUUKd8RxQZ3xfYhdqH7RDSP49A63i4Bp/1Gjy6vu8noKvFt0TONghN05LxBP9Pjd Z2gocjKulpebrON6nHFPPJv7MY3bwf8lJ7FYif34zmxYAATWBzxRSmBkmcY8yD2OxrLM 2SwxB8F0gnFlc/SFdOXhWKiy2h5lBJdpJlG9p0O955MAy6lm3RUSFyMcuaxXIcueFO+1 6hrA== X-Gm-Message-State: APjAAAXEN85tM6K1B7qpmhDpgMTx6J8GINmF3vq2vhQzO1954VSnpkr1 JWsgGmH2C5mBN8/9xVrKArXlOQ== X-Google-Smtp-Source: APXvYqxg7D1dBaCApAPv7fIACWzG+g9WKWTF3nPZnp2Y8FQoJuPpNUulT0HNxVkqcL+FpeHfn+LPYA== X-Received: by 2002:a65:5bc3:: with SMTP id o3mr21255099pgr.226.1575937119193; Mon, 09 Dec 2019 16:18:39 -0800 (PST) Received: from cakuba.netronome.com ([66.60.152.14]) by smtp.gmail.com with ESMTPSA id g8sm617234pfh.43.2019.12.09.16.18.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 09 Dec 2019 16:18:39 -0800 (PST) Date: Mon, 9 Dec 2019 16:18:35 -0800 From: Jakub Kicinski To: Maciej =?UTF-8?B?xbtlbmN6eWtvd3NraQ==?= Cc: "David S . Miller" , Linux Network Development Mailing List , Marcelo Ricardo Leitner , Sean Tranchetti , Eric Dumazet , Linux SCTP , Subash Abhinov Kasiviswanathan Subject: Re: [PATCH v2] net: introduce ip_local_unbindable_ports sysctl Message-ID: <20191209161835.7c455fc0@cakuba.netronome.com> In-Reply-To: References: <20191209224530.156283-1-zenczykowski@gmail.com> <20191209154216.7e19e0c0@cakuba.netronome.com> Organization: Netronome Systems, Ltd. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Tue, 10 Dec 2019 01:02:08 +0100, Maciej =C5=BBenczykowski wrote: > > Could you elaborate what protocols and products are in need of this > > functionality? =20 >=20 > The ones I'm aware of are: > (a) Google's servers > (b) Android on at least some chipsets (Qualcomm at the bare minimum, > but I think it's pretty standard a solution) where there's a complex > port sharing scheme between the Linux kernel on the Application > Processor and the Firmware running on the modem (for ipv4 we only get > one ip address from the cellular carrier). It's basically required > for things like wifi calling to work. Okay, that's what I was suspecting. It'd be great if the real motivation for a patch was spelled out in the commit message :/ So some SoCs which run non-vanilla kernels require hacks to steal ports from the networking stack for use by proprietary firmware. I don't see how merging this patch benefits the community. > > Why can't the NIC just get its own IP like it usually does with NCSI? = =20 >=20 > Because often these nics are deployed as in place upgrades in > environments where there's a limited number of IPs. > Say a rack with a /27 ipv4 subnet (2**5 =3D 32 -> 29 usable ips, since > network/broadcast/gateway are burned) and 15+ pre-existing machines. > This means there's not enough IPs to assign separate ones for the nics. > Renumbering the rack, would imply renumbering the datacenter, etc... > And ipv4 - even RFC1918 - has long run out - so even in new > deployments there's not enough IPv4 ips to give to nics, and IPv6 > isn't yet deployed *everywhere*. So the conditions for this are: - in-place upgrade of an existing rack - IPv4 only - the existing servers didn't have NCSI or otherwise IPs for OOB control Unlike the AP one this sounds like a very rare scenario.. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jakub Kicinski Date: Tue, 10 Dec 2019 00:18:35 +0000 Subject: Re: [PATCH v2] net: introduce ip_local_unbindable_ports sysctl Message-Id: <20191209161835.7c455fc0@cakuba.netronome.com> List-Id: References: <20191209224530.156283-1-zenczykowski@gmail.com> <20191209154216.7e19e0c0@cakuba.netronome.com> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable To: Maciej =?UTF-8?B?xbtlbmN6eWtvd3NraQ==?= Cc: "David S . Miller" , Linux Network Development Mailing List , Marcelo Ricardo Leitner , Sean Tranchetti , Eric Dumazet , Linux SCTP , Subash Abhinov Kasiviswanathan On Tue, 10 Dec 2019 01:02:08 +0100, Maciej =C5=BBenczykowski wrote: > > Could you elaborate what protocols and products are in need of this > > functionality? =20 >=20 > The ones I'm aware of are: > (a) Google's servers > (b) Android on at least some chipsets (Qualcomm at the bare minimum, > but I think it's pretty standard a solution) where there's a complex > port sharing scheme between the Linux kernel on the Application > Processor and the Firmware running on the modem (for ipv4 we only get > one ip address from the cellular carrier). It's basically required > for things like wifi calling to work. Okay, that's what I was suspecting. It'd be great if the real motivation for a patch was spelled out in the commit message :/ So some SoCs which run non-vanilla kernels require hacks to steal ports from the networking stack for use by proprietary firmware. I don't see how merging this patch benefits the community. > > Why can't the NIC just get its own IP like it usually does with NCSI? = >=20 > Because often these nics are deployed as in place upgrades in > environments where there's a limited number of IPs. > Say a rack with a /27 ipv4 subnet (2**5 =3D 32 -> 29 usable ips, since > network/broadcast/gateway are burned) and 15+ pre-existing machines. > This means there's not enough IPs to assign separate ones for the nics. > Renumbering the rack, would imply renumbering the datacenter, etc... > And ipv4 - even RFC1918 - has long run out - so even in new > deployments there's not enough IPv4 ips to give to nics, and IPv6 > isn't yet deployed *everywhere*. So the conditions for this are: - in-place upgrade of an existing rack - IPv4 only - the existing servers didn't have NCSI or otherwise IPs for OOB control Unlike the AP one this sounds like a very rare scenario..