From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: multipart/mixed; boundary="===============3521718557854406061==" MIME-Version: 1.0 From: Andrea Arcangeli To: lkp@lists.01.org Subject: Re: [ksm] 40e318e509: ltp.ksm01.fail Date: Mon, 25 Jan 2016 15:54:26 +0100 Message-ID: <20160125145426.GB12228@redhat.com> In-Reply-To: <87io2ibbrh.fsf@yhuang-dev.intel.com> List-Id: --===============3521718557854406061== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Hello, On Mon, Jan 25, 2016 at 11:04:18AM +0800, kernel test robot wrote: > FYI, we noticed the below changes on > = > https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master > commit 40e318e509d2c9f3cdb00ef32d2c14b9868af16b ("ksm: introduce ksm_max_= page_sharing per page deduplication limit") > = > We found LKP KSM test case failed for your patch. > = > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > compiler/kconfig/rootfs/tbox_group/test/testcase: > gcc-5/x86_64-nfsroot/debian-x86_64-2015-02-07.cgz/vm-lkp-wsx03-4G/mm_fu= nctional_positive/otc_kernel_qa-ts_ltp_ddt > = > commit: = > 77505a33e539477f1fbe5e6136df5b265f39cccf > 40e318e509d2c9f3cdb00ef32d2c14b9868af16b > = > 77505a33e539477f 40e318e509d2c9f3cdb00ef32d = > ---------------- -------------------------- = > fail:runs %reproduction fail:runs > | | | = > :4 100% 4:4 otc_kernel_qa-ts_ltp_ddt.ks= m01.fail > :4 100% 4:4 otc_kernel_qa-ts_ltp_ddt.ks= m01_1.fail In this case it's one rare case of false positive. The change in the merging levels is a "feature" not a "bug". LTP validation math on ksm sysfs levels shall be updated to account for the runtime value of /sys/kernel/mm/ksm/max_page_sharing which in turn affects pages_sharing/pages_shared. In fact you could add validation for the new fields like stable_node_dups and stable_node_chains on top of the existing verifications on pages_shar*. For now you should re-run the test after: echo 2 >/sys/kernel/mm/ksm/run echo 10000000 > /sys/kernel/mm/ksm/max_page_sharing echo 1 >/sys/kernel/mm/ksm/run And then LTP will pass as usual. Thanks for the greatly valuable regression testing work, Andrea --===============3521718557854406061==-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932694AbcAYOyd (ORCPT ); Mon, 25 Jan 2016 09:54:33 -0500 Received: from mx1.redhat.com ([209.132.183.28]:55328 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932395AbcAYOy3 (ORCPT ); Mon, 25 Jan 2016 09:54:29 -0500 Date: Mon, 25 Jan 2016 15:54:26 +0100 From: Andrea Arcangeli To: kernel test robot Cc: lkp@01.org, LKML , Andrew Morton , Arjan van de Ven , Davidlohr Bueso , Hugh Dickins , Petr Holasek , Stephen Rothwell Subject: Re: [lkp] [ksm] 40e318e509: ltp.ksm01.fail Message-ID: <20160125145426.GB12228@redhat.com> References: <87io2ibbrh.fsf@yhuang-dev.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87io2ibbrh.fsf@yhuang-dev.intel.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Mon, Jan 25, 2016 at 11:04:18AM +0800, kernel test robot wrote: > FYI, we noticed the below changes on > > https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master > commit 40e318e509d2c9f3cdb00ef32d2c14b9868af16b ("ksm: introduce ksm_max_page_sharing per page deduplication limit") > > We found LKP KSM test case failed for your patch. > > ========================================================================================= > compiler/kconfig/rootfs/tbox_group/test/testcase: > gcc-5/x86_64-nfsroot/debian-x86_64-2015-02-07.cgz/vm-lkp-wsx03-4G/mm_functional_positive/otc_kernel_qa-ts_ltp_ddt > > commit: > 77505a33e539477f1fbe5e6136df5b265f39cccf > 40e318e509d2c9f3cdb00ef32d2c14b9868af16b > > 77505a33e539477f 40e318e509d2c9f3cdb00ef32d > ---------------- -------------------------- > fail:runs %reproduction fail:runs > | | | > :4 100% 4:4 otc_kernel_qa-ts_ltp_ddt.ksm01.fail > :4 100% 4:4 otc_kernel_qa-ts_ltp_ddt.ksm01_1.fail In this case it's one rare case of false positive. The change in the merging levels is a "feature" not a "bug". LTP validation math on ksm sysfs levels shall be updated to account for the runtime value of /sys/kernel/mm/ksm/max_page_sharing which in turn affects pages_sharing/pages_shared. In fact you could add validation for the new fields like stable_node_dups and stable_node_chains on top of the existing verifications on pages_shar*. For now you should re-run the test after: echo 2 >/sys/kernel/mm/ksm/run echo 10000000 > /sys/kernel/mm/ksm/max_page_sharing echo 1 >/sys/kernel/mm/ksm/run And then LTP will pass as usual. Thanks for the greatly valuable regression testing work, Andrea