Received: by 2002:ac0:bc90:0:0:0:0:0 with SMTP id a16csp3422157img; Mon, 25 Mar 2019 09:58:43 -0700 (PDT) X-Google-Smtp-Source: APXvYqzvaUFlj/3O27tMfkrfgIfbYlDMaOEVBNVN1Qh4EgXNrwhPCtKw46BlHecdQfmbXSlA5xHF X-Received: by 2002:a17:902:112c:: with SMTP id d41mr26543487pla.177.1553533123690; Mon, 25 Mar 2019 09:58:43 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1553533123; cv=none; d=google.com; s=arc-20160816; b=LCJLw+5dovnB1DoaJ7p/xsA96vs8QxbC+8wACk72AiYmzLSGM5pO5ovfxBFBlzW0ce Dyd00DTJqFO6Nb3SzgM9+rAkkz7pANmTP6Sfj3ybr6izifiASCroY1DoGwOajJzEQB8n xxpKn/TYG/oQlFNqgE/XpFqUruFU4okECCXCj83NOiGwoM4Jfu3ub0Vr4VDCwnhdPJwD mO2+OFHDDaBRogLr+Tw6DzhH2EAUMrRilAJSOCizJ0XCk2E6ALHi2w5twH3Eocl7VREH wFuafEeAOqXuwniXqqLrpsJAD71pI14oUOFD1fzX+pDlB7nQ9trMhuUta+/dVG2rLwxj DiyQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:message-id:date:content-id:mime-version :subject:cc:to:references:in-reply-to:from:organization; bh=GFce7apBIQSgCSiYECfUCF9dM0HAJUzq988HSOztGGU=; b=ZDeMxCaeLQBRnjQnhhLiOLXpAVGc8yr9+gsCgqTmHFknTEb7A+2nJ9jeOjfZUH3cxl 5jStOIYiukpVAsCM1OOaaxoo0YwrMyW2KlNvf8yr7WvDz/i4mXiaGhZ92vR7Czt5h83U uQT2943Qz3YSq3Buc1xni0uJFOhak4meqXT74qXd2Vzfahr50rmWk0g51ecqDWKqEBhr Y2BBTQ3LXXRt6o5orWmfjtAgGpfDfM7Mgc9feeZ2yDOXngfqI7J4x2Ae/UhfGtkoL4ry 81baSd4tXqj83WuxKJfaAC19ASoIusueWPoysVx6gHAZ2X7OPPjPKoNruP+/n7vUJcax 5j2g== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=redhat.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id y6si13991181plk.126.2019.03.25.09.58.28; Mon, 25 Mar 2019 09:58:43 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729610AbfCYQ4g (ORCPT + 99 others); Mon, 25 Mar 2019 12:56:36 -0400 Received: from mx1.redhat.com ([209.132.183.28]:46722 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725788AbfCYQ4f (ORCPT ); Mon, 25 Mar 2019 12:56:35 -0400 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 3556F2D7E6; Mon, 25 Mar 2019 16:56:35 +0000 (UTC) Received: from warthog.procyon.org.uk (ovpn-121-98.rdu2.redhat.com [10.10.121.98]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3D3D71001E70; Mon, 25 Mar 2019 16:56:19 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: References: <20190325162052.28987-1-christian@brauner.io> To: Daniel Colascione Cc: dhowells@redhat.com, Christian Brauner , Jann Horn , khlebnikov@yandex-team.ru, Andy Lutomirski , "Serge E. Hallyn" , "Eric W. Biederman" , Linux API , linux-kernel , Arnd Bergmann , Kees Cook , Alexey Dobriyan , Thomas Gleixner , Michael Kerrisk-manpages , bl0pbl33p@gmail.com, "Dmitry V. Levin" , Andrew Morton , Oleg Nesterov , nagarathnam.muthusamy@oracle.com, Aleksa Sarai , Al Viro , Joel Fernandes Subject: Re: [PATCH 0/4] pid: add pidctl() MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <18682.1553532974.1@warthog.procyon.org.uk> Date: Mon, 25 Mar 2019 16:56:14 +0000 Message-ID: <18683.1553532974@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Mon, 25 Mar 2019 16:56:35 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Daniel Colascione wrote: > System calls are cheap. Only to a point. x86_64 will have an issue when we hit syscall 512. We're currently at 427. David