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=-3.9 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 13F69C433E2 for ; Tue, 15 Sep 2020 11:25:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8C041206E6 for ; Tue, 15 Sep 2020 11:25:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=ellerman.id.au header.i=@ellerman.id.au header.b="prKzwknF" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726125AbgIOLZm (ORCPT ); Tue, 15 Sep 2020 07:25:42 -0400 Received: from bilbo.ozlabs.org ([203.11.71.1]:49329 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726242AbgIOLYu (ORCPT ); Tue, 15 Sep 2020 07:24:50 -0400 Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4BrLVM70dlz9sVM; Tue, 15 Sep 2020 21:24:43 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ellerman.id.au; s=201909; t=1600169084; bh=vwQV7qeFTU97cqEIIJI2HqYzEK96icuAhdrJc1SZ50c=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=prKzwknFVr9DjUmmzGOx6sGZ3/ZPjF5DldXo/d/XmMWSmSYb0s3ySkcsIUw+FO5SZ GiDFjbh5ayGPdxxCjV7DbprPsL4p1d03V6pLg5m+cTO9RdPbYMu8pETXZf4gPwDcso PyFQkhVjvaQ8qaJeQ0nhHhdTJgOVdSyk9MuXtgplYpBXcokTAmrpQXE025EdIpTvS2 U2tfrEg2SZRnsMQWPEEMP94Lujy0o8a+U1OKVHEVVMbHpINk8fr1B4uytBGwV4LB/x HBPUVmEDUpXgaJspAWwyL1mvQPT5t+k1oNc/s1b+cS/hd5TVZZNcSjRZ/u3T+La5KM 3ri0sJl1bXIZg== From: Michael Ellerman To: Sachin Sant , linux-next@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org, willy@infradead.org Subject: Re: [5.9.0-rc5-20200914] Kernel crash while running LTP(mlock201) In-Reply-To: <3DCED508-4DC0-42AA-9CFF-3AB260ED1E9A@linux.vnet.ibm.com> References: <3DCED508-4DC0-42AA-9CFF-3AB260ED1E9A@linux.vnet.ibm.com> Date: Tue, 15 Sep 2020 21:24:38 +1000 Message-ID: <87o8m7p9jd.fsf@mpe.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Sender: linux-next-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-next@vger.kernel.org Sachin Sant writes: > While running LTP tests (specifically mlock201) against next-20200914 tree > on a POWER9 LPAR results in following crash. Looks the same as: https://lore.kernel.org/linux-mm/20200914085545.GB28738@shao2-debian/ cheers > BUG: Kernel NULL pointer dereference on read at 0x00000000 > Faulting instruction address: 0xc000000000454248 > Oops: Kernel access of bad area, sig: 11 [#1] > LE PAGE_SIZE=3D64K MMU=3DHash SMP NR_CPUS=3D2048 NUMA pSeries > Modules linked in: af_packet(E) nft_ct(E) nf_conntrack(E) nf_defrag_ipv6(= E) nf_defrag_ipv4(E) libcrc32c(E) ip6_tables(E) nft_compat(E) ip_set(E) rfk= ill(E) nf_tables(E) nfnetlink(E) vmx_crypto(E) uio_pdrv_genirq(E) gf128mul(= E) uio(E) rtc_generic(E) crct10dif_vpmsum(E) sch_fq_codel(E) ip_tables(E) x= _tables(E) ext4(E) crc16(E) mbcache(E) jbd2(E) sd_mod(E) t10_pi(E) sg(E) ib= mvscsi(E) scsi_transport_srp(E) scsi_mod(E) ibmveth(E) crc32c_vpmsum(E) dm_= mirror(E) dm_region_hash(E) dm_log(E) dm_mod(E) autofs4(E) > CPU: 11 PID: 26435 Comm: mlock201 Tainted: G E 5.9.0-rc5-n= ext-20200914-281.gf529200-default #1 > NIP: c000000000454248 LR: c000000000445a74 CTR: c000000000413150 > REGS: c0000008e645b770 TRAP: 0300 Tainted: G E (5.9.0-r= c5-next-20200914-281.gf529200-default) > MSR: 8000000000009033 CR: 28002482 XER: 20040000 > CFAR: c00000000000fbb0 DAR: 0000000000000000 DSISR: 40000000 IRQMASK: 0=20 > GPR00: c000000000445a74 c0000008e645ba00 c0000000017c4500 000000000000000= 0=20 > GPR04: 0000000000000001 c0000008ea109e98 c0000008f0c40000 000000000000000= 0=20 > GPR08: 0000000000000000 0000000000000000 0000000000000000 000000000000000= 3=20 > GPR12: c000000000413150 c00000001ec70200 0000000000000000 c00000000150203= 8=20 > GPR16: 00007fff9c61ffff 00007fff9c61ffff 00007fff9c61ffff c000000000cb02f= 8=20 > GPR20: 00007fff9c5c0000 00007fff9c620000 c0000008e645bcd8 c0000008f0c4000= 0=20 > GPR24: c00c0000023c0d00 fffffffffffffe7f 0000000000000000 c0000008f0c4000= 0=20 > GPR28: c0000008ea109e98 0000000000000001 c0000008ea9288a8 000000000000000= 0=20 > NIP [c000000000454248] PageHuge+0x8/0x60 > LR [c000000000445a74] find_get_incore_page+0x114/0x160 > Call Trace: > [c0000008e645ba00] [c000000000445994] find_get_incore_page+0x34/0x160 (un= reliable) > [c0000008e645ba40] [c000000000412e54] mincore_page+0x24/0x160 > [c0000008e645ba70] [c000000000413020] __mincore_unmapped_range+0x90/0x160 > [c0000008e645bac0] [c000000000413680] mincore_pte_range+0x530/0x5d0 > [c0000008e645bb40] [c000000000422a38] walk_pgd_range+0x4e8/0xae0 > [c0000008e645bc30] [c0000000004230c4] __walk_page_range+0x94/0x250 > [c0000008e645bcb0] [c0000000004233d8] walk_page_range+0x158/0x1e0 > [c0000008e645bd40] [c00000000041386c] sys_mincore+0x14c/0x370 > [c0000008e645bdc0] [c000000000033eb8] system_call_exception+0xf8/0x200 > [c0000008e645be20] [c00000000000d140] system_call_common+0xf0/0x27c > Instruction dump: > e8410018 38210020 e8010010 7c0803a6 4e800020 60000000 3d400001 7d435378=20 > 4e800020 60000000 7c0802a6 60000000 75290001 40820010 e9230008= =20 > ---[ end trace 357eb14a3b22eab2 ]=E2=80=94 > > > The function find_get_incore_page() was introduced with=20 > 3fcbe4eb49a0406e6202e8c8c3560f30965a8e79=20 > > mm: factor find_get_incore_page out of mincore_page > > > Thanks > -Sachin