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=-3.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 2732AC2BB86 for ; Thu, 9 Apr 2020 22:18:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F3A0720B1F for ; Thu, 9 Apr 2020 22:18:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="cMUYiBy5" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726951AbgDIWS1 (ORCPT ); Thu, 9 Apr 2020 18:18:27 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:22275 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726872AbgDIWS1 (ORCPT ); Thu, 9 Apr 2020 18:18:27 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1586470707; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=wak+4fOkmGwWiUN+MnpwHwLxfkg3pyB2FLjyHTCXGe0=; b=cMUYiBy5gbI3t45FJRnkkIzfZtcnxa1+BeqSKPnKsKwhvVXzuZc/V4ePhuLBCZ03zBGQKR PAknRmspyRa5UWWzJXoBCyHGQrjTHc4JJE7VgAdiWv6OZFWC+UvesvnLPUZEyauE0ZQtyJ Wd7skqmyehUHZNRiplzgw4y+lyfaUJM= Received: from mail-qv1-f72.google.com (mail-qv1-f72.google.com [209.85.219.72]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-93-k-EzJbwwMge0ZzZeFaSQhA-1; Thu, 09 Apr 2020 18:18:23 -0400 X-MC-Unique: k-EzJbwwMge0ZzZeFaSQhA-1 Received: by mail-qv1-f72.google.com with SMTP id f9so100308qvt.14 for ; Thu, 09 Apr 2020 15:18:23 -0700 (PDT) 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:references :mime-version:content-disposition:in-reply-to; bh=wak+4fOkmGwWiUN+MnpwHwLxfkg3pyB2FLjyHTCXGe0=; b=nPFh3Hv+v2VCAcW5d8LCBVqqM7n5voWC8LbQlZMIDNmCAfHI1jIOB6B+H/goewEaIq kykyANbFbTuKoxKyuyjr3/eRwXsEYPcMGG2HlHQHF0EjPVA/Zeis3fD4go73rXYH/oC6 2AC0TTRXnlZGlwko6mfjn3q7ckCSrjHkQOOpo+hvojAdBedj/bE3Ej71a6/MGZQBAjdK opB0lEVQcn7LU1eqt1fVqsoMN61aRFcUhb7JR2wSPb7BkSTfHbIVXcmrpLgJRTCJqwyQ WhyO7WFSugRSXbomfUhlpO7NMmPiBVhrO261YxH9i1CroAfdQDCdEUe0XoJ2L21cKTrk 6pqg== X-Gm-Message-State: AGi0Pub/7Ovsa8uJOeTLuwXpYNedvaeUe+W3A2P+U3oI3aN+MzZk2xqF JolOgV4XeezJZje9GN3OXJpVB/SZ0I+mpZFMFjkj+SkewRTfpP2c4X3UaHH4vaEoyg4FX38kzla kIq8WeX0s243opLHfEDIoHFu8 X-Received: by 2002:a37:4117:: with SMTP id o23mr1141041qka.295.1586470702715; Thu, 09 Apr 2020 15:18:22 -0700 (PDT) X-Google-Smtp-Source: APiQypIJD/iTRAWfSQIyFtDJJdk3323wKWVJn7GNTy0DpExPfZvgf67+NsccoV0ON/i9YnqzueJ/4g== X-Received: by 2002:a37:4117:: with SMTP id o23mr1141019qka.295.1586470702419; Thu, 09 Apr 2020 15:18:22 -0700 (PDT) Received: from xz-x1 ([2607:9880:19c0:32::2]) by smtp.gmail.com with ESMTPSA id o18sm165603qkk.52.2020.04.09.15.18.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 09 Apr 2020 15:18:21 -0700 (PDT) Date: Thu, 9 Apr 2020 18:18:19 -0400 From: Peter Xu To: Mike Kravetz Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Nitesh Narayan Lal , Andrew Morton Subject: Re: [PATCH] Documentation: hugetlb: Update hugetlb options Message-ID: <20200409221819.GA3172@xz-x1> References: <20200409215800.8967-1-peterx@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Apr 09, 2020 at 03:08:07PM -0700, Mike Kravetz wrote: > On 4/9/20 2:58 PM, Peter Xu wrote: > > The hugepage options are not documented clearly. > > > > Firstly, default_hugepagesz= should always be specified after the > > declaration of the same type of huge page using hugepagesz=. For > > example, if we boot a x86_64 system with kernel cmdline > > "default_hugepagesz=2M", we'll get a very funny error message: > > > > "HugeTLB: unsupported default_hugepagesz 2097152. Reverting to 2097152" > > > > It's understandable from code-wise because when hugetlb_init() we > > didn't have the 2M page hstate registered, so it's unsupported. > > However 2M is actually the default huge page size on x86_64, so we'll > > register it right after the error message. However it's very > > confusing if without these knowledges. > > > > Secondly, hugepages= option must be used _after_ another hugepagesz=. > > The word "interleave" is fine but it didn't declare the fact that > > each of the hugepages= option will be applied to the previous parsed > > hugepagesz= option. > > > > State all these clear. > > > > Signed-off-by: Peter Xu > > Hi Peter, > > Did you happen to see this patch series? > > https://lore.kernel.org/linux-mm/20200401183819.20647-1-mike.kravetz@oracle.com/ > > That should address the documentation issue and more. Great! I missed that, but I'll definitely read it (probably tomorrow). Let's ignore this patch then. Thanks, -- Peter Xu