From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: mx.groups.io; dkim=missing; spf=pass (domain: redhat.com, ip: 209.132.183.28, mailfrom: lersek@redhat.com) Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by groups.io with SMTP; Tue, 17 Sep 2019 05:06:50 -0700 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 946E6C057F23; Tue, 17 Sep 2019 12:06:49 +0000 (UTC) Received: from lacos-laptop-7.usersys.redhat.com (ovpn-120-37.rdu2.redhat.com [10.10.120.37]) by smtp.corp.redhat.com (Postfix) with ESMTP id DDF9360126; Tue, 17 Sep 2019 12:06:46 +0000 (UTC) Subject: Re: [edk2-devel] [edk2] DxeIpl : create page table, occupied too much memory range To: devel@edk2.groups.io, tigerliu@zhaoxin.com References: <5eabf2c9104644ba955a4c3a4de983dc@zhaoxin.com> From: "Laszlo Ersek" Message-ID: <2aca1445-6688-cb20-c0e3-938a4c4acd38@redhat.com> Date: Tue, 17 Sep 2019 14:06:45 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <5eabf2c9104644ba955a4c3a4de983dc@zhaoxin.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Tue, 17 Sep 2019 12:06:49 +0000 (UTC) Content-Type: text/plain; charset=windows-1252 Content-Language: en-US Content-Transfer-Encoding: 7bit On 09/17/19 13:08, Tiger Liu(BJ-RD) wrote: > Hi, Expert: > I have a question about creating page table. > If a CPU support 48bit physical address line, then creating page tables(Page size=2MB) will occupy too much memory region. > > Now, developer could only use PcdUse1GPageTable to avoid occupy too much memory region? Not only. See . Thanks Laszlo