From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.6 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2019BC433E6 for ; Tue, 1 Sep 2020 10:03:01 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id BE429206A5 for ; Tue, 1 Sep 2020 10:03:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BE429206A5 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4BgjLV61WZzDqZb for ; Tue, 1 Sep 2020 20:02:58 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=arm.com (client-ip=217.140.110.172; helo=foss.arm.com; envelope-from=anshuman.khandual@arm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=arm.com Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lists.ozlabs.org (Postfix) with ESMTP id 4BgjG75H43zDqXX for ; Tue, 1 Sep 2020 19:59:11 +1000 (AEST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id DC11630E; Tue, 1 Sep 2020 02:59:09 -0700 (PDT) Received: from [10.163.69.134] (unknown [10.163.69.134]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 1711B3F71F; Tue, 1 Sep 2020 02:59:04 -0700 (PDT) From: Anshuman Khandual Subject: Re: [PATCH v3 09/13] mm/debug_vm_pgtable/locks: Move non page table modifying test together To: "Aneesh Kumar K.V" , linux-mm@kvack.org, akpm@linux-foundation.org References: <20200827080438.315345-1-aneesh.kumar@linux.ibm.com> <20200827080438.315345-10-aneesh.kumar@linux.ibm.com> <9b75b175-f319-d40e-a95e-b323b3db654a@arm.com> <58a5280f-4882-4a36-c52d-15ad879209d6@linux.ibm.com> Message-ID: <4fad7c4b-14ca-b558-504b-6b20a6c85ec3@arm.com> Date: Tue, 1 Sep 2020 15:28:32 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <58a5280f-4882-4a36-c52d-15ad879209d6@linux.ibm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arch@vger.kernel.org, linux-s390@vger.kernel.org, Christophe Leroy , x86@kernel.org, Mike Rapoport , Qian Cai , Gerald Schaefer , Vineet Gupta , linux-snps-arc@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On 09/01/2020 03:06 PM, Aneesh Kumar K.V wrote: > >>>> >>>> [   17.080644] ------------[ cut here ]------------ >>>> [   17.081342] kernel BUG at mm/pgtable-generic.c:164! >>>> [   17.082091] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP >>>> [   17.082977] Modules linked in: >>>> [   17.083481] CPU: 79 PID: 1 Comm: swapper/0 Tainted: G        W         5.9.0-rc2-00105-g740e72cd6717 #14 >>>> [   17.084998] Hardware name: linux,dummy-virt (DT) >>>> [   17.085745] pstate: 60400005 (nZCv daif +PAN -UAO BTYPE=--) >>>> [   17.086645] pc : pgtable_trans_huge_deposit+0x58/0x60 >>>> [   17.087462] lr : debug_vm_pgtable+0x4dc/0x8f0 >>>> [   17.088168] sp : ffff80001219bcf0 >>>> [   17.088710] x29: ffff80001219bcf0 x28: ffff8000114ac000 >>>> [   17.089574] x27: ffff8000114ac000 x26: 0020000000000fd3 >>>> [   17.090431] x25: 0020000081400fd3 x24: fffffe00175c12c0 >>>> [   17.091286] x23: ffff0005df04d1a8 x22: 0000f18d6e035000 >>>> [   17.092143] x21: ffff0005dd790000 x20: ffff0005df18e1a8 >>>> [   17.093003] x19: ffff0005df04cb80 x18: 0000000000000014 >>>> [   17.093859] x17: 00000000b76667d0 x16: 00000000fd4e6611 >>>> [   17.094716] x15: 0000000000000001 x14: 0000000000000002 >>>> [   17.095572] x13: 000000000055d966 x12: fffffe001755e400 >>>> [   17.096429] x11: 0000000000000008 x10: ffff0005fcb6e210 >>>> [   17.097292] x9 : ffff0005fcb6e210 x8 : 0020000081590fd3 >>>> [   17.098149] x7 : ffff0005dd71e0c0 x6 : ffff0005df18e1a8 >>>> [   17.099006] x5 : 0020000081590fd3 x4 : 0020000081590fd3 >>>> [   17.099862] x3 : ffff0005df18e1a8 x2 : fffffe00175c12c0 >>>> [   17.100718] x1 : fffffe00175c1300 x0 : 0000000000000000 >>>> [   17.101583] Call trace: >>>> [   17.101993]  pgtable_trans_huge_deposit+0x58/0x60 >>>> [   17.102754]  do_one_initcall+0x74/0x1cc >>>> [   17.103381]  kernel_init_freeable+0x1d0/0x238 >>>> [   17.104089]  kernel_init+0x14/0x118 >>>> [   17.104658]  ret_from_fork+0x10/0x34 >>>> [   17.105251] Code: f9000443 f9000843 f9000822 d65f03c0 (d4210000) >>>> [   17.106303] ---[ end trace e63471e00f8c147f ]--- >>>> >>> >>> IIUC, this should happen even without the series right? This is >>> >>>      assert_spin_locked(pmd_lockptr(mm, pmdp)); >> >> Crash does not happen without this series. A previous patch [PATCH v3 08/13] >> added pgtable_trans_huge_deposit/withdraw() in pmd_advanced_tests(). arm64 >> does not define __HAVE_ARCH_PGTABLE_DEPOSIT and hence falls back on generic >> pgtable_trans_huge_deposit() which the asserts the lock. >> > > > I fixed that by moving the pgtable deposit after adding the pmd locks correctly. > > mm/debug_vm_pgtable/locks: Move non page table modifying test together > mm/debug_vm_pgtable/locks: Take correct page table lock > mm/debug_vm_pgtable/thp: Use page table depost/withdraw with THP Right, it does fix. But then both those patches should be folded/merged in order to preserve git bisect ability, besides test classification reasons as mentioned in a previous response and a possible redundant movement of hugetlb_basic_tests().