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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 3662FC433FF for ; Wed, 31 Jul 2019 12:09:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0AD03208E3 for ; Wed, 31 Jul 2019 12:09:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564574943; bh=SInHiofjgRi6cQb0T69CsQ8lJPIHN1g6yLmZe6X9VMc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=EtJ/MKVnMvU97egx4NhOqGQwDc/kZUaJlbvCrVALnfyTSFt2d24U5YS54/WyOSE3s RcLYXwvUpRBccwPv5sebou+K+GKL+9L+oDnscVqP8Ay6Pzo4Ve42pfldmdXBHqHKjd vCjpySTy+12QaZVveGJbHTuJKTUDvGtMdRB1mF0s= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729019AbfGaMJB (ORCPT ); Wed, 31 Jul 2019 08:09:01 -0400 Received: from mx2.suse.de ([195.135.220.15]:34628 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725793AbfGaMJB (ORCPT ); Wed, 31 Jul 2019 08:09:01 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 56879AF30; Wed, 31 Jul 2019 12:09:00 +0000 (UTC) Date: Wed, 31 Jul 2019 14:08:59 +0200 From: Michal Hocko To: Rashmica Gupta Cc: Oscar Salvador , David Hildenbrand , Andrew Morton , Dan Williams , pasha.tatashin@soleen.com, Jonathan.Cameron@huawei.com, anshuman.khandual@arm.com, Vlastimil Babka , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 0/5] Allocate memmap from hotadded memory Message-ID: <20190731120859.GJ9330@dhcp22.suse.cz> References: <20190625075227.15193-1-osalvador@suse.de> <2ebfbd36-11bd-9576-e373-2964c458185b@redhat.com> <20190626080249.GA30863@linux> <2750c11a-524d-b248-060c-49e6b3eb8975@redhat.com> <20190626081516.GC30863@linux> <887b902e-063d-a857-d472-f6f69d954378@redhat.com> <9143f64391d11aa0f1988e78be9de7ff56e4b30b.camel@gmail.com> <20190702074806.GA26836@linux> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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 Tue 02-07-19 18:52:01, Rashmica Gupta wrote: [...] > > 2) Why it was designed, what is the goal of the interface? > > 3) When it is supposed to be used? > > > > > There is a hardware debugging facility (htm) on some power chips. To use > this you need a contiguous portion of memory for the output to be dumped > to - and we obviously don't want this memory to be simultaneously used by > the kernel. How much memory are we talking about here? Just curious. -- Michal Hocko SUSE Labs