From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3vHWLB06d5zDqBQ for ; Tue, 7 Feb 2017 15:18:41 +1100 (AEDT) Received: from pps.filterd (m0098409.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.20/8.16.0.20) with SMTP id v174IdeI051438 for ; Mon, 6 Feb 2017 23:18:39 -0500 Received: from e23smtp04.au.ibm.com (e23smtp04.au.ibm.com [202.81.31.146]) by mx0a-001b2d01.pphosted.com with ESMTP id 28euphh00t-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Mon, 06 Feb 2017 23:18:39 -0500 Received: from localhost by e23smtp04.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 7 Feb 2017 14:18:34 +1000 Received: from d23relay08.au.ibm.com (d23relay08.au.ibm.com [9.185.71.33]) by d23dlp02.au.ibm.com (Postfix) with ESMTP id 184F62BB005B for ; Tue, 7 Feb 2017 15:18:32 +1100 (EST) Received: from d23av02.au.ibm.com (d23av02.au.ibm.com [9.190.235.138]) by d23relay08.au.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v174IND927918482 for ; Tue, 7 Feb 2017 15:18:31 +1100 Received: from d23av02.au.ibm.com (localhost [127.0.0.1]) by d23av02.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id v174I0lR015772 for ; Tue, 7 Feb 2017 15:18:00 +1100 From: "Aneesh Kumar K.V" To: Benjamin Herrenschmidt , paulus@samba.org, mpe@ellerman.id.au Cc: linuxppc-dev@lists.ozlabs.org Subject: Re: [RFC PATCH 5/5] powerpc/mm/hash: Increase VA range to 256TB In-Reply-To: <1486440373.4850.114.camel@kernel.crashing.org> References: <1486439333-22162-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <1486439333-22162-6-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <1486440373.4850.114.camel@kernel.crashing.org> Date: Tue, 07 Feb 2017 09:47:41 +0530 MIME-Version: 1.0 Content-Type: text/plain Message-Id: <87lgtir5wa.fsf@skywalker.in.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Benjamin Herrenschmidt writes: > That's 48 bits. I would keep the limit at 47 without some explicit > opt-in by applications. That's what users get on x86 and we know > some GPUs have limits there. The idea is to have linux personality values that will limit the effective address to different memory range. By default max effective address will be limited to 64TB. Applications can then extend this to 128TB or 512TB. So we will have two personality values PER_LINUX_128TB and PER_LINUX_512TB ? -aneesh