From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Hansen Subject: Re: [PATCH 00/10] mm: adjust get_user_pages* functions to explicitly pass FOLL_* flags Date: Wed, 19 Oct 2016 10:23:55 -0700 Message-ID: <5807AC2B.4090208@linux.intel.com> References: <20161013002020.3062-1-lstoakes@gmail.com> <20161018153050.GC13117@dhcp22.suse.cz> <20161019085815.GA22239@lucifer> <20161019090727.GE7517@dhcp22.suse.cz> <5807A427.7010200@linux.intel.com> <20161019170127.GN24393@dhcp22.suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <20161019170127.GN24393@dhcp22.suse.cz> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Michal Hocko Cc: linux-mips@linux-mips.org, linux-fbdev@vger.kernel.org, Jan Kara , kvm@vger.kernel.org, linux-sh@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-mm@kvack.org, netdev@vger.kernel.org, sparclinux@vger.kernel.org, linux-ia64@vger.kernel.org, linux-s390@vger.kernel.org, linux-samsung-soc@vger.kernel.org, linux-scsi@vger.kernel.org, linux-rdma@vger.kernel.org, x86@kernel.org, Hugh Dickins , linux-media@vger.kernel.org, Rik van Riel , intel-gfx@lists.freedesktop.org, adi-buildroot-devel@lists.sourceforge.net, ceph-devel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Lorenzo Stoakes , linux-cris-kernel@axis.com, Linus Torvalds , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org, linux-alpha@vger.kernel.org, linux-fs List-Id: ceph-devel.vger.kernel.org T24gMTAvMTkvMjAxNiAxMDowMSBBTSwgTWljaGFsIEhvY2tvIHdyb3RlOgo+IFRoZSBxdWVzdGlv biBJIGhhZCBlYXJsaWVyIHdhcyB3aGV0aGVyIHRoaXMgaGFzIHRvIGJlIGFuIGV4cGxpY2l0IEZP TEwKPiBmbGFnIHVzZWQgYnkgZy11LXAgdXNlcnMgb3Igd2UgY2FuIGp1c3QgdXNlIGl0IGludGVy bmFsbHkgd2hlbiBtbSAhPQo+IGN1cnJlbnQtPm1tCgpUaGUgcmVhc29uIEkgY2hvc2Ugbm90IHRv IGRvIHRoYXQgd2FzIHRoYXQgZGVmZXJyZWQgd29yayBnZXRzIHJ1biB1bmRlcgphIGJhc2ljYWxs eSByYW5kb20gJ2N1cnJlbnQnLiAgSWYgd2UganVzdCB1c2UgJ21tICE9IGN1cnJlbnQtPm1tJywg dGhlbgp0aGUgZGVmZXJyZWQgd29yayB3aWxsIHNvbWV0aW1lcyBoYXZlIHBrZXlzIGVuZm9yY2Vk IGFuZCBzb21ldGltZXMgbm90LApiYXNpY2FsbHkgcmFuZG9tbHkuCgpXZSB3YW50IHRvIGJlIGNv bnNpc3RlbnQgd2l0aCB3aGV0aGVyIHRoZXkgYXJlIGVuZm9yY2VkIG9yIG5vdCwgc28gd2UKZXhw bGljaXRseSBpbmRpY2F0ZSB0aGF0IGJ5IGNhbGxpbmcgdGhlIHJlbW90ZSB2YXJpYW50IHZzLiBw bGFpbi4KX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KSW50 ZWwtZ2Z4IG1haWxpbmcgbGlzdApJbnRlbC1nZnhAbGlzdHMuZnJlZWRlc2t0b3Aub3JnCmh0dHBz Oi8vbGlzdHMuZnJlZWRlc2t0b3Aub3JnL21haWxtYW4vbGlzdGluZm8vaW50ZWwtZ2Z4Cg== From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Hansen Date: Wed, 19 Oct 2016 17:23:55 +0000 Subject: Re: [PATCH 00/10] mm: adjust get_user_pages* functions to explicitly pass FOLL_* flags Message-Id: <5807AC2B.4090208@linux.intel.com> List-Id: References: <20161013002020.3062-1-lstoakes@gmail.com> <20161018153050.GC13117@dhcp22.suse.cz> <20161019085815.GA22239@lucifer> <20161019090727.GE7517@dhcp22.suse.cz> <5807A427.7010200@linux.intel.com> <20161019170127.GN24393@dhcp22.suse.cz> In-Reply-To: <20161019170127.GN24393@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Michal Hocko Cc: linux-mips@linux-mips.org, linux-fbdev@vger.kernel.org, Jan Kara , kvm@vger.kernel.org, linux-sh@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-mm@kvack.org, netdev@vger.kernel.org, sparclinux@vger.kernel.org, linux-ia64@vger.kernel.org, linux-s390@vger.kernel.org, linux-samsung-soc@vger.kernel.org, linux-scsi@vger.kernel.org, linux-rdma@vger.kernel.org, x86@kernel.org, Hugh Dickins , linux-media@vger.kernel.org, Rik van Riel , intel-gfx@lists.freedesktop.org, adi-buildroot-devel@lists.sourceforge.net, ceph-devel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Lorenzo Stoakes , linux-cris-kernel@axis.com, Linus Torvalds , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org, linux-alpha@vger.kernel.org, linux-fs On 10/19/2016 10:01 AM, Michal Hocko wrote: > The question I had earlier was whether this has to be an explicit FOLL > flag used by g-u-p users or we can just use it internally when mm !> current->mm The reason I chose not to do that was that deferred work gets run under a basically random 'current'. If we just use 'mm != current->mm', then the deferred work will sometimes have pkeys enforced and sometimes not, basically randomly. We want to be consistent with whether they are enforced or not, so we explicitly indicate that by calling the remote variant vs. plain. From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Wed, 19 Oct 2016 19:24:03 +0200 (CEST) Received: from mga02.intel.com ([134.134.136.20]:20995 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by eddie.linux-mips.org with ESMTP id S23990519AbcJSRX5YxzQv (ORCPT ); Wed, 19 Oct 2016 19:23:57 +0200 Received: from orsmga004.jf.intel.com ([10.7.209.38]) by orsmga101.jf.intel.com with ESMTP; 19 Oct 2016 10:23:55 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.31,367,1473145200"; d="scan'208";a="21749372" Received: from ray.jf.intel.com (HELO [10.7.201.146]) ([10.7.201.146]) by orsmga004.jf.intel.com with ESMTP; 19 Oct 2016 10:23:55 -0700 Subject: Re: [PATCH 00/10] mm: adjust get_user_pages* functions to explicitly pass FOLL_* flags To: Michal Hocko References: <20161013002020.3062-1-lstoakes@gmail.com> <20161018153050.GC13117@dhcp22.suse.cz> <20161019085815.GA22239@lucifer> <20161019090727.GE7517@dhcp22.suse.cz> <5807A427.7010200@linux.intel.com> <20161019170127.GN24393@dhcp22.suse.cz> Cc: Lorenzo Stoakes , linux-mm@kvack.org, Linus Torvalds , Jan Kara , Hugh Dickins , Rik van Riel , Mel Gorman , Andrew Morton , adi-buildroot-devel@lists.sourceforge.net, ceph-devel@vger.kernel.org, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, kvm@vger.kernel.org, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-cris-kernel@axis.com, linux-fbdev@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linux-mips@linux-mips.org, linux-rdma@vger.kernel.org, linux-s390@vger.kernel.org, linux-samsung-soc@vger.kernel.org, linux-scsi@vger.kernel.org, linux-security-module@vger.kernel.org, linux-sh@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, netdev@vger.kernel.org, sparclinux@vger.kernel.org, x86@kernel.org From: Dave Hansen Message-ID: <5807AC2B.4090208@linux.intel.com> Date: Wed, 19 Oct 2016 10:23:55 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.8.0 MIME-Version: 1.0 In-Reply-To: <20161019170127.GN24393@dhcp22.suse.cz> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 55518 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: dave.hansen@linux.intel.com Precedence: bulk List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-Id: linux-mips X-List-ID: linux-mips List-subscribe: List-owner: List-post: List-archive: X-list: linux-mips On 10/19/2016 10:01 AM, Michal Hocko wrote: > The question I had earlier was whether this has to be an explicit FOLL > flag used by g-u-p users or we can just use it internally when mm != > current->mm The reason I chose not to do that was that deferred work gets run under a basically random 'current'. If we just use 'mm != current->mm', then the deferred work will sometimes have pkeys enforced and sometimes not, basically randomly. We want to be consistent with whether they are enforced or not, so we explicitly indicate that by calling the remote variant vs. plain. From mboxrd@z Thu Jan 1 00:00:00 1970 From: dave.hansen@linux.intel.com (Dave Hansen) Date: Wed, 19 Oct 2016 10:23:55 -0700 Subject: [PATCH 00/10] mm: adjust get_user_pages* functions to explicitly pass FOLL_* flags In-Reply-To: <20161019170127.GN24393@dhcp22.suse.cz> References: <20161013002020.3062-1-lstoakes@gmail.com> <20161018153050.GC13117@dhcp22.suse.cz> <20161019085815.GA22239@lucifer> <20161019090727.GE7517@dhcp22.suse.cz> <5807A427.7010200@linux.intel.com> <20161019170127.GN24393@dhcp22.suse.cz> Message-ID: <5807AC2B.4090208@linux.intel.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 10/19/2016 10:01 AM, Michal Hocko wrote: > The question I had earlier was whether this has to be an explicit FOLL > flag used by g-u-p users or we can just use it internally when mm != > current->mm The reason I chose not to do that was that deferred work gets run under a basically random 'current'. If we just use 'mm != current->mm', then the deferred work will sometimes have pkeys enforced and sometimes not, basically randomly. We want to be consistent with whether they are enforced or not, so we explicitly indicate that by calling the remote variant vs. plain. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: [PATCH 00/10] mm: adjust get_user_pages* functions to explicitly pass FOLL_* flags To: Michal Hocko References: <20161013002020.3062-1-lstoakes@gmail.com> <20161018153050.GC13117@dhcp22.suse.cz> <20161019085815.GA22239@lucifer> <20161019090727.GE7517@dhcp22.suse.cz> <5807A427.7010200@linux.intel.com> <20161019170127.GN24393@dhcp22.suse.cz> Cc: Lorenzo Stoakes , linux-mm@kvack.org, Linus Torvalds , Jan Kara , Hugh Dickins , Rik van Riel , Mel Gorman , Andrew Morton , adi-buildroot-devel@lists.sourceforge.net, ceph-devel@vger.kernel.org, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, kvm@vger.kernel.org, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-cris-kernel@axis.com, linux-fbdev@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linux-mips@linux-mips.org, linux-rdma@vger.kernel.org, linux-s390@vger.kernel.org, linux-samsung-soc@vger.kernel.org, linux-scsi@vger.kernel.org, linux-security-module@vger.kernel.org, linux-sh@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, netdev@vger.kernel.org, sparclinux@vger.kernel.org, x86@kernel.org From: Dave Hansen Message-ID: <5807AC2B.4090208@linux.intel.com> Date: Wed, 19 Oct 2016 10:23:55 -0700 MIME-Version: 1.0 In-Reply-To: <20161019170127.GN24393@dhcp22.suse.cz> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: On 10/19/2016 10:01 AM, Michal Hocko wrote: > The question I had earlier was whether this has to be an explicit FOLL > flag used by g-u-p users or we can just use it internally when mm != > current->mm The reason I chose not to do that was that deferred work gets run under a basically random 'current'. If we just use 'mm != current->mm', then the deferred work will sometimes have pkeys enforced and sometimes not, basically randomly. We want to be consistent with whether they are enforced or not, so we explicitly indicate that by calling the remote variant vs. plain. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org