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=-0.9 required=3.0 tests=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 351C2C76191 for ; Thu, 25 Jul 2019 04:47:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0EC112190F for ; Thu, 25 Jul 2019 04:47:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=canb.auug.org.au header.i=@canb.auug.org.au header.b="K+j5/UFi" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390219AbfGYErR (ORCPT ); Thu, 25 Jul 2019 00:47:17 -0400 Received: from ozlabs.org ([203.11.71.1]:47551 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390204AbfGYErR (ORCPT ); Thu, 25 Jul 2019 00:47:17 -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 45vKSf27J0z9sBt; Thu, 25 Jul 2019 14:47:13 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=canb.auug.org.au; s=201702; t=1564030034; bh=XgNiyUC/8j8tQYX8YJAPfwm9flwHUimtQeGsqjcgCgk=; h=Date:From:To:Cc:Subject:From; b=K+j5/UFiVp1yASqfFfYtxDs/Io9FD0y/x41FEDqoGc0fAHf5rlVnAQmDp1Djf9m8h n55DtPVvc01KxlvO2xp6E2SjGeUZ/7SlntUyZAl/hUqPrr94v7XmAGbdOVm6Tb2xLr KMEXt4BdioAo7CjNU7ZSor1NIMzw6YWCGxI7nqQxmxAIkT7VIMNMPJg2/wIqF3c2rc QEn4XtWdPQG9BNxOnQV0D4s0oiWVcyA4k478X4bPhvCGfad7fhUYyV4xweAD3TeHWB h/cmW+567geuOxcCWRxtPX+//PLKHmk8ZXaQmwiyI9kyn75JFDJNb5kOBEImaw1Tt+ JRMJ6hJr6qZYA== Date: Thu, 25 Jul 2019 14:47:12 +1000 From: Stephen Rothwell To: Al Viro Cc: Linux Next Mailing List , Linux Kernel Mailing List , Nikolay Borisov Subject: linux-next: run time BUG after merge of the vfs-fixes tree? Message-ID: <20190725144712.39cb1e5b@canb.auug.org.au> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="Sig_/pEgeTEg2=EXC5OrdPMK6f02"; protocol="application/pgp-signature"; micalg=pgp-sha256 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --Sig_/pEgeTEg2=EXC5OrdPMK6f02 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Hi all, During my qemu boot tests (powerpc64 pseries_le_defconfig) today, I got the following BUG: # halt # Stopping network...Saving random seed... [ 6.515368] random: dd: unini= tialized urandom read (512 bytes read) done. Stopping logging: OK [ 6.796972] BUG: Unable to handle kernel data access at 0x5deadbeef00001= 22 [ 6.797133] Faulting instruction address: 0xc00000000041cba4 [ 6.797616] Oops: Kernel access of bad area, sig: 11 [#1] [ 6.797725] LE PAGE_SIZE=3D64K MMU=3DHash SMP NR_CPUS=3D2048 NUMA pSeries [ 6.797987] Modules linked in: [ 6.798405] CPU: 0 PID: 111 Comm: umount Not tainted 5.3.0-rc1 #2 [ 6.798554] NIP: c00000000041cba4 LR: c00000000041cb90 CTR: 00000000000= 001fc [ 6.798664] REGS: c00000007e1eba70 TRAP: 0380 Not tainted (5.3.0-rc1) [ 6.798716] MSR: 8000000000009033 CR: 82242884 = XER: 20000000 [ 6.798957] CFAR: c00000000041c434 IRQMASK: 0=20 [ 6.798957] GPR00: c00000000041cb90 c00000007e1ebd00 c00000000110e100 00= 00000000000001=20 [ 6.798957] GPR04: 0000000000000800 0000000000000800 0000000000020000 c0= 0000000113dbf8=20 [ 6.798957] GPR08: 0000000000000048 c00000007a2e2100 5deadbeef0000122 c0= 00000079417380=20 [ 6.798957] GPR12: 0000000022242884 c0000000012f0000 0000000000000000 00= 00000000000000=20 [ 6.798957] GPR16: 0000000000000000 0000000000000000 0000000000000000 00= 00000000000000=20 [ 6.798957] GPR20: 0000000000000000 0000000000000000 0000000000000000 00= 000000100bce20=20 [ 6.798957] GPR24: 0000000000000000 c00000007a2e2100 0000000000000000 c0= 0000007a2e2188=20 [ 6.798957] GPR28: 0000000000000000 5deadbeef0000100 5deadbeef0000122 5d= eadbeef0000100=20 [ 6.800143] NIP [c00000000041cba4] namespace_unlock+0x194/0x240 [ 6.800208] LR [c00000000041cb90] namespace_unlock+0x180/0x240 [ 6.800366] Call Trace: [ 6.800456] [c00000007e1ebd00] [c00000000041cb90] namespace_unlock+0x180= /0x240 (unreliable) [ 6.800603] [c00000007e1ebd60] [c00000000041e634] ksys_umount+0x324/0x6f0 [ 6.800760] [c00000007e1ebe00] [c00000000041ea24] sys_umount+0x24/0x40 [ 6.800824] [c00000007e1ebe20] [c00000000000ba64] system_call+0x5c/0x70 [ 6.800940] Instruction dump: [ 6.801234] 81490124 fba900f0 fbc900f8 2f8a0000 409e00b0 7d234b78 4bfff8= 0d 353fff10=20 [ 6.801374] 4182007c ebe900f0 e94900f8 2fbf0000 409effc8 3ce0= 5dea 60e7dbee=20 [ 6.801992] ---[ end trace 34315779952607e2 ]--- [ 6.905920]=20 The system is going down NOW! 5deadbeef is the ppc64 ILLEGAL_POINTER_VALUE. I am guessing that the problem may have been introduced by commit 2085eeffbc6d ("fix the struct mount leak in umount_tree()") in the vfs-fixes tree today. And actually reverting that commit makes the BUG go away. After doing the revert (and also before today), I get the following log messages instead of the BUG trace: umount: devtmpfs busy - remounted read-only umount: can't unmount /: Invalid argument So, I have left that commit reverted for today. --=20 Cheers, Stephen Rothwell --Sig_/pEgeTEg2=EXC5OrdPMK6f02 Content-Type: application/pgp-signature Content-Description: OpenPGP digital signature -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEENIC96giZ81tWdLgKAVBC80lX0GwFAl05NFAACgkQAVBC80lX 0GzMCgf/Z43iUTipx8OAm5+vbL33R6EKfD0dTufyKZFYSro17WVkUYcE27nQmYbj PII9tbx+S1uDvwMMX/0RumvK3aM2ygkf93RcVobI0D8+X95TCQe3Sx6IgsW2Uk8E lX7f3Nfzpcm29EdQJZ52c6x2wALnCmvQubFPi5E0q9azIrD/5Ih49pLrL3O2moiB z+7pCABIEr9eu5nEAFDDrOdyWgrwslY+ogZdmQo7KSqXYuX5yHqk/wWE6VVGAtCR bAEVczy8LFUONlQfIGmbULLZ+CFQ8djj7Izdf3aktfWUMHiD6iJLi9JsXOdg7aB/ c4KSHUCk9Jn5CFkjN2IPikJ6JJCS5w== =9j6j -----END PGP SIGNATURE----- --Sig_/pEgeTEg2=EXC5OrdPMK6f02--