From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ram Pai Subject: Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0 Date: Fri, 9 Mar 2018 12:06:31 -0800 Message-ID: <20180309200631.GS1060@ram.oc3035372033.ibm.com> References: <1520583161-11741-1-git-send-email-linuxram@us.ibm.com> <87lgf1v9di.fsf@concordia.ellerman.id.au> Reply-To: Ram Pai Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8BIT Return-path: Content-Disposition: inline In-Reply-To: <87lgf1v9di.fsf@concordia.ellerman.id.au> Sender: linux-kernel-owner@vger.kernel.org To: Michael Ellerman Cc: mingo@redhat.com, akpm@linux-foundation.org, linuxppc-dev@lists.ozlabs.org, linux-mm@kvack.org, x86@kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, dave.hansen@intel.com, benh@kernel.crashing.org, paulus@samba.org, khandual@linux.vnet.ibm.com, aneesh.kumar@linux.vnet.ibm.com, bsingharora@gmail.com, hbabu@us.ibm.com, mhocko@kernel.org, bauerman@linux.vnet.ibm.com, ebiederm@xmission.com, corbet@lwn.net, arnd@arndb.de, fweimer@redhat.com, msuchanek@suse.com, Ulrich.Weigand@de.ibm.com List-Id: linux-arch.vger.kernel.org On Fri, Mar 09, 2018 at 09:19:53PM +1100, Michael Ellerman wrote: > Ram Pai writes: > > > Once an address range is associated with an allocated pkey, it cannot be > > reverted back to key-0. There is no valid reason for the above behavior. On > > the contrary applications need the ability to do so. > > Please explain this in much more detail. Is it an ABI change? Not necessarily an ABI change. older binary applications will continue to work. It can be considered as a bug-fix. > > And why did we just notice this? Yes. this was noticed by an application vendor. > > > The patch relaxes the restriction. > > > > Tested on powerpc and x86_64. > > Thanks, but please split the patch, one for each arch. Will do. RP From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:38440 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932286AbeCIUGr (ORCPT ); Fri, 9 Mar 2018 15:06:47 -0500 Received: from pps.filterd (m0098416.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w29JvdA4134962 for ; Fri, 9 Mar 2018 15:06:47 -0500 Received: from e06smtp14.uk.ibm.com (e06smtp14.uk.ibm.com [195.75.94.110]) by mx0b-001b2d01.pphosted.com with ESMTP id 2gkuqxd7dv-1 (version=TLSv1.2 cipher=AES256-SHA256 bits=256 verify=NOT) for ; Fri, 09 Mar 2018 15:06:46 -0500 Received: from localhost by e06smtp14.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 9 Mar 2018 20:06:45 -0000 Date: Fri, 9 Mar 2018 12:06:31 -0800 From: Ram Pai Subject: Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0 Reply-To: Ram Pai References: <1520583161-11741-1-git-send-email-linuxram@us.ibm.com> <87lgf1v9di.fsf@concordia.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: 8BIT In-Reply-To: <87lgf1v9di.fsf@concordia.ellerman.id.au> Message-ID: <20180309200631.GS1060@ram.oc3035372033.ibm.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Michael Ellerman Cc: mingo@redhat.com, akpm@linux-foundation.org, linuxppc-dev@lists.ozlabs.org, linux-mm@kvack.org, x86@kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, dave.hansen@intel.com, benh@kernel.crashing.org, paulus@samba.org, khandual@linux.vnet.ibm.com, aneesh.kumar@linux.vnet.ibm.com, bsingharora@gmail.com, hbabu@us.ibm.com, mhocko@kernel.org, bauerman@linux.vnet.ibm.com, ebiederm@xmission.com, corbet@lwn.net, arnd@arndb.de, fweimer@redhat.com, msuchanek@suse.com, Ulrich.Weigand@de.ibm.com Message-ID: <20180309200631.0qT9LymKihs_ZHRAzMqX_lg9HD2h1k_SH3BW9lUTR18@z> On Fri, Mar 09, 2018 at 09:19:53PM +1100, Michael Ellerman wrote: > Ram Pai writes: > > > Once an address range is associated with an allocated pkey, it cannot be > > reverted back to key-0. There is no valid reason for the above behavior. On > > the contrary applications need the ability to do so. > > Please explain this in much more detail. Is it an ABI change? Not necessarily an ABI change. older binary applications will continue to work. It can be considered as a bug-fix. > > And why did we just notice this? Yes. this was noticed by an application vendor. > > > The patch relaxes the restriction. > > > > Tested on powerpc and x86_64. > > Thanks, but please split the patch, one for each arch. Will do. RP