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=-2.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 F0EB0ECDE30 for ; Wed, 17 Oct 2018 15:34:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A7BEE21526 for ; Wed, 17 Oct 2018 15:34:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="GhjC1vBB" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A7BEE21526 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com 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 S1727678AbeJQXag (ORCPT ); Wed, 17 Oct 2018 19:30:36 -0400 Received: from mail-pl1-f169.google.com ([209.85.214.169]:39574 "EHLO mail-pl1-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727132AbeJQXag (ORCPT ); Wed, 17 Oct 2018 19:30:36 -0400 Received: by mail-pl1-f169.google.com with SMTP id e67-v6so3889828plb.6; Wed, 17 Oct 2018 08:34:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:date:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=QBRxG95r8ZrcYQnbvom0ck3HkqSUVTuSdsWpCvsF4t4=; b=GhjC1vBBZGFzKw4DQsaJ/PotEPUTG93x7tiizOmV3p+RhRFx0Lwo+h0/ycC33R9TiC I1O1Q5eG5Tq8x55nnvtXkgTHLlNEg0jSd/2dXu77eVdY5104dB/svcyeTWh+q+X0uvZR BBOpVdc25HU8RgGO3GgSK75RV6xesd/qS40CGYG8R0GalZSXsKnwgN0zHE1Vncmc5iFQ LK1wGc34Th6Y7l6xo6KymHJE5cofiPwJMEfgw8usT/SSV8gkvTxR+WXw/vVfsVH3Whcw cL+SVSp7jWHZ4K6B9tot65JpmjJyWVFDq0ys3QlIz2/8FnzvTZdA3mxHuEas7tMLkeG4 CBgg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:date:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=QBRxG95r8ZrcYQnbvom0ck3HkqSUVTuSdsWpCvsF4t4=; b=SdO2vwQDaXi+mbHyxjgITKWMVIGf9mH0i0q6Tiv8YzepbiYRtKSMIKmBCb1XMnocdV UL17PCawGZv89edSB3CagmPTcP05tpXkODinnddvvdDCV2C4WOc/v0YPcatfrz/Lz8Ym Uc6idUMNVpT0DSFPg8Fa8X9SuGPzyMk8GGsmYLPyHBx+795RyHemfhn6KOgh30LU5qFA mtWqdOKQu7uqE29WvvU+0Gm8F6mpOGv/Unlo2IBQOJmmLWbaO6ONOHV4pM0FRauNnS9c ss72SNH+eDnAj+p2BjSCyaAbCQZmQz8VZ26zcA95sP1b8GWfqfpLPnxLcPMeDqy3/hOA dwrw== X-Gm-Message-State: ABuFfog8WoiTIKxlVMBH7Nc99kahZJkWh/+D00/uWPRp9bHlskXbEMvD gpugD//3b4NSRddSy7iKiww= X-Google-Smtp-Source: ACcGV60gUaiTTCKOibj2CfIHg7xlVPMrAB1Evy45v/YzEZINRjtE4fwT+44IPVegF/ph2GfxcolZDQ== X-Received: by 2002:a17:902:e185:: with SMTP id cd5-v6mr25518845plb.224.1539790461756; Wed, 17 Oct 2018 08:34:21 -0700 (PDT) Received: from localhost ([121.137.63.184]) by smtp.gmail.com with ESMTPSA id p24-v6sm24042142pgm.70.2018.10.17.08.34.20 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 17 Oct 2018 08:34:20 -0700 (PDT) From: Sergey Senozhatsky X-Google-Original-From: Sergey Senozhatsky Date: Thu, 18 Oct 2018 00:34:08 +0900 To: Mathieu Desnoyers Cc: Sergey Senozhatsky , rostedt , Peter Zijlstra , "Paul E. 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Peter Anvin" , Andi Kleen , Chris Lameter , Ben Maurer , Josh Triplett , Linus Torvalds , Catalin Marinas , Will Deacon , Michael Kerrisk , Joel Fernandes Subject: Re: [RFC PATCH for 4.21 04/16] mm: Introduce vm_map_user_ram, vm_unmap_user_ram Message-ID: <20181017153408.GB426@tigerII.localdomain> References: <20181010191936.7495-1-mathieu.desnoyers@efficios.com> <20181010191936.7495-5-mathieu.desnoyers@efficios.com> <20181016143016.10da89bd@gandalf.local.home> <20181017002722.GA1068@jagdpanzerIV> <1051015468.759.1539788401096.JavaMail.zimbra@efficios.com> <2060193272.771.1539788641739.JavaMail.zimbra@efficios.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <2060193272.771.1539788641739.JavaMail.zimbra@efficios.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (10/17/18 11:04), Mathieu Desnoyers wrote: > >> > >>> if (WARN_ON(x)) > >>> return; > >> > >> Given that this somewhat MM-related, I'd may be say VM_WARN_ON(). > > I notice that VM_WARN_ON() casts the result of WARN_ON() to (void), so it > cannot be used in a if () statement. > > VM_WARN_ON() will only warn if CONFIG_DEBUG_VM is set. > > Is it really what we want ? Oh, indeed... Sorry, I forgot that they cast WANR_ON() return to void. Let's do what Steven suggested. -ss