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=-2.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 65AB6C41536 for ; Tue, 20 Nov 2018 17:39:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3140420684 for ; Tue, 20 Nov 2018 17:39:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="Tv+IJpr8" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3140420684 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729298AbeKUEJf (ORCPT ); Tue, 20 Nov 2018 23:09:35 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:60860 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729143AbeKUEJf (ORCPT ); Tue, 20 Nov 2018 23:09:35 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=ObZd+2EAI/2J8E0S2Wv13fI9xuoKlVew8XcoQeC5j/4=; b=Tv+IJpr8CPpzFfehFjbBjdRb/ OaKzzc0bj9mdT3kc2xzyXbwqCoReDDPX7rxId5rRqMcOAm5a0qNhlzWnQH4Mtgrj1Nw+8Fpj4KO3s bT7L4EsSPmS8LJTixx4khS4ErYT+StLQDyUAlQszY8+GQOMHurf3OC8j+gtXzyQZ4rsdzRq1h+Saa THqk3rJwYgXp2JnGm344LMXbNy3EL2H+WXTD/xt2IJE9ptOlb8LPAqdpG/KJeTz6Jca/PvMfbpaH0 Q6aAQ+VPajLkbMMFVMurwZ6UWI6KwLaU+jpsWjNvtDdX9E4/xESOeMHXYP5GQc/HlVRlcykMEn61X JGLhNmnLA==; Received: from willy by bombadil.infradead.org with local (Exim 4.90_1 #2 (Red Hat Linux)) id 1gP9zU-0003Be-QJ; Tue, 20 Nov 2018 17:39:12 +0000 Date: Tue, 20 Nov 2018 09:39:12 -0800 From: Matthew Wilcox To: Pavel Machek Cc: Vlastimil Babka , Daniel Colascione , linux-kernel@vger.kernel.org, rppt@linux.ibm.com, timmurray@google.com, joelaf@google.com, surenb@google.com, Jonathan Corbet , Andrew Morton , Roman Gushchin , Mike Rapoport , "Kirill A. Shutemov" , "Dennis Zhou (Facebook)" , Prashant Dhamdhere , "open list:DOCUMENTATION" Subject: Re: [PATCH v2] Document /proc/pid PID reuse behavior Message-ID: <20181120173912.GD3065@bombadil.infradead.org> References: <20181031150625.147369-1-dancol@google.com> <20181105132205.138695-1-dancol@google.com> <20181119105426.GD28607@amd> <1c5caa66-3c61-cb57-754a-f099200c73b2@suse.cz> <20181120091829.GD16916@amd> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181120091829.GD16916@amd> User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 20, 2018 at 10:18:29AM +0100, Pavel Machek wrote: > > would ever rely on the pid being reused while having the descriptor > > open. How would that make sense? > > I agree this is corner space, but users might be surprised that > keeping FDs of /proc/pid/X would lead to PID space exhaustion, for > example. We have a limit on the number of FDs a process can have open for a reason. Well, for many reasons.