From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f50.google.com (mail-pa0-f50.google.com [209.85.220.50]) by kanga.kvack.org (Postfix) with ESMTP id 772BD6B0005 for ; Mon, 7 Mar 2016 14:16:05 -0500 (EST) Received: by mail-pa0-f50.google.com with SMTP id bj10so83756247pad.2 for ; Mon, 07 Mar 2016 11:16:05 -0800 (PST) Received: from shards.monkeyblade.net (shards.monkeyblade.net. [2001:4f8:3:36:211:85ff:fe63:a549]) by mx.google.com with ESMTP id ey12si4380794pac.203.2016.03.07.11.16.04 for ; Mon, 07 Mar 2016 11:16:04 -0800 (PST) Date: Mon, 07 Mar 2016 14:16:00 -0500 (EST) Message-Id: <20160307.141600.1873883635480850431.davem@davemloft.net> Subject: Re: [PATCH v2] sparc64: Add support for Application Data Integrity (ADI) From: David Miller In-Reply-To: <56DDC776.3040003@oracle.com> References: <56DDC2B6.6020009@oracle.com> <56DDC3EB.8060909@oracle.com> <56DDC776.3040003@oracle.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: khalid.aziz@oracle.com Cc: rob.gardner@oracle.com, corbet@lwn.net, akpm@linux-foundation.org, dingel@linux.vnet.ibm.com, bob.picco@oracle.com, kirill.shutemov@linux.intel.com, aneesh.kumar@linux.vnet.ibm.com, aarcange@redhat.com, arnd@arndb.de, sparclinux@vger.kernel.org, mhocko@suse.cz, chris.hyser@oracle.com, richard@nod.at, vbabka@suse.cz, koct9i@gmail.com, oleg@redhat.com, gthelen@google.com, jack@suse.cz, xiexiuqi@huawei.com, Vineet.Gupta1@synopsys.com, luto@kernel.org, ebiederm@xmission.com, bsegall@google.com, geert@linux-m68k.org, dave@stgolabs.net, adobriyan@gmail.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org From: Khalid Aziz Date: Mon, 7 Mar 2016 11:24:54 -0700 > Tags can be cleared by user by setting tag to 0. Tags are > automatically cleared by the hardware when the mapping for a virtual > address is removed from TSB (which is why swappable pages are a > problem), so kernel does not have to do it as part of clean up. You might be able to crib some bits for the Tag in the swp_entry_t, it's 64-bit and you can therefore steal bits from the offset field. That way you'll have the ADI tag in the page tables, ready to re-install at swapin time. -- 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