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=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 8A979C606C8 for ; Mon, 8 Jul 2019 18:07:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7191721874 for ; Mon, 8 Jul 2019 18:07:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387996AbfGHSHI (ORCPT ); Mon, 8 Jul 2019 14:07:08 -0400 Received: from zeniv.linux.org.uk ([195.92.253.2]:60474 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726501AbfGHSHH (ORCPT ); Mon, 8 Jul 2019 14:07:07 -0400 Received: from viro by ZenIV.linux.org.uk with local (Exim 4.92 #3 (Red Hat Linux)) id 1hkY2U-0003oz-6Z; Mon, 08 Jul 2019 18:06:58 +0000 Date: Mon, 8 Jul 2019 19:06:58 +0100 From: Al Viro To: Christian Borntraeger Cc: Stephen Rothwell , Linux Next Mailing List , Linux Kernel Mailing List , Heiko Carstens , Vasily Gorbik , markward@linux.ibm.com Subject: Re: linux-next: Tree for Jul 8 --> bootup failure on s390x (bisected) Message-ID: <20190708180657.GV17978@ZenIV.linux.org.uk> References: <20190708224238.60bd0aff@canb.auug.org.au> <0be7464d-f8ed-0567-b0ff-a6d31ecfd7a8@de.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <0be7464d-f8ed-0567-b0ff-a6d31ecfd7a8@de.ibm.com> User-Agent: Mutt/1.11.3 (2019-02-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 08, 2019 at 06:52:14PM +0200, Christian Borntraeger wrote: > smp: Brought up 1 node, 1 CPU > Unable to handle kernel pointer dereference in virtual kernel address space > Failing address: 000000003a070000 TEID: 000000003a070407 > Fault in home space mode while using kernel ASCE. > AS:000000003a780007 R3:000000007ffd0007 S:000000007ffd4800 P:000000003a07021d > Oops: 0004 ilc:2 [#1] SMP > Modules linked in: > CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.2.0-rc5-00101-gcb8f0b366109 #14 > Hardware name: IBM 2964 NC9 712 (KVM/Linux) > Krnl PSW : 0704e00180000000 000000003974b580 (shmem_parse_monolithic+0x88/0x100) > R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 > Krnl GPRS: 0000000000000000 000000000000003d 000000003a07040e 000000000000003d > 000000003a07040f 000000000000006d 0000000000000001 0000000000000000 > 000000007f7c1c00 0000000000000000 000000003a07040a 0000000000000000 > 000000007f7e4000 000000003a190d78 000000003974b56c 000003e00031fd38 > Krnl Code: 000000003974b574: b920002a cgr %r2,%r10 > 000000003974b578: a784001b brc 8,3974b5ae > #000000003974b57c: 41402001 la %r4,1(%r2) > >000000003974b580: 92002000 mvi 0(%r2),0 > 000000003974b584: a7090000 lghi %r0,0 > 000000003974b588: b9040014 lgr %r1,%r4 > 000000003974b58c: b25e0001 srst %r0,%r1 > 000000003974b590: a714fffe brc 1,3974b58c > Call Trace: > ([<000003e00031fd80>] 0x3e00031fd80) > [<0000000039811662>] vfs_kern_mount.part.0+0x9a/0xc8 > [<000000003a302fc0>] devtmpfs_init+0x38/0x140 > [<000000003a302e0a>] driver_init+0x22/0x60 > [<000000003a2beff8>] kernel_init_freeable+0x298/0x4f0 > [<0000000039e7b53a>] kernel_init+0x22/0x148 > [<0000000039e87b70>] ret_from_fork+0x30/0x34 > [<0000000039e87b74>] kernel_thread_starter+0x0/0xc > INFO: lockdep is turned off. > [...] Oh, fuck... OK, I understand what's going on; sorry, my fault. Could you verify that the following helps? diff --git a/drivers/base/devtmpfs.c b/drivers/base/devtmpfs.c index 52312c665a38..30d0523014e0 100644 --- a/drivers/base/devtmpfs.c +++ b/drivers/base/devtmpfs.c @@ -431,9 +431,10 @@ static int devtmpfsd(void *p) */ int __init devtmpfs_init(void) { + char opts[] = "mode=0755"; int err; - mnt = vfs_kern_mount(&internal_fs_type, 0, "devtmpfs", "mode=0755"); + mnt = vfs_kern_mount(&internal_fs_type, 0, "devtmpfs", opts); if (IS_ERR(mnt)) { printk(KERN_ERR "devtmpfs: unable to create devtmpfs %ld\n", PTR_ERR(mnt));