From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751971AbdEDHL3 (ORCPT ); Thu, 4 May 2017 03:11:29 -0400 Received: from mail-pf0-f195.google.com ([209.85.192.195]:35871 "EHLO mail-pf0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751458AbdEDHLV (ORCPT ); Thu, 4 May 2017 03:11:21 -0400 Date: Thu, 4 May 2017 16:11:18 +0900 From: Stafford Horne To: lokeshvutla@ti.com, LKML Cc: Murali Karicheri , Al Viro Subject: [BUG] OpenRISC exec init fails, bisected to 0886551 ("initramfs: finish fput() before accessing any binary from initramfs") Message-ID: <20170504071118.GA17317@lianli.shorne-pla.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.8.0 (2017-02-23) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, While booting the v4.11 kernel I found the below issue. The summary of the issue mentions Commit 4a9d4b024a31 ("switch fput to task_work_add") implements a schedule_work() for completing fput(), but did not guarantee calling __fput() after unpacking initramfs. Because of this, there is a possibility that during boot a driver can see ETXTBSY when it tries to load a binary from initramfs as fput() is still pending on that binary. It seems this patch (0886551) introduces that issue though? I am looking into it, but any suggestions would be helpful. BOOT LOG Compiled-in FDT at c03b9100 Linux version 4.10.0-10351-g0886551 (shorne@lianli.shorne-pla.net) (gcc version 5.4.0 (GCC) ) #223 Thu May 4 16:01:02 JST 2017 CPU: OpenRISC-0 (revision 0) @20 MHz ... Freeing unused kernel memory: 2856K This architecture does not have kernel memory protection. Failed to execute /init (error -26) Starting init: /sbin/init exists but couldn't execute it (error -26) Starting init: /bin/sh exists but couldn't execute it (error -26) Kernel panic - not syncing: No working init found. Try passing init= option to kernel. See Linux Documentation/admin-guide/init.rst for guidance. ---[ end Kernel panic - not syncing: No working init found. Try passing init= option to kernel. See Linux Documentation/admin-guide/init.rst for guidance. TO REPRODUCE The failure is intermittent. Using some tools: - initramfs: https://github.com/stffrdhrn/or1k-utils - compiler: https://github.com/openrisc/or1k-gcc/releases (or1k-linux-5.4.0-20170218.tar.xz) - qemu: version 2.9 Make and run using: make ARCH=openrisc defconfig make -j5 ARCH=openrisc CROSS_COMPILE=or1k-linux- \ CONFIG_INITRAMFS_SOURCE="../openrisc/or1k-utils/initramfs ../openrisc/or1k-utils/initramfs.devnodes" qemu-system-or1k -cpu or1200 -M or1k-sim -kernel vmlinux -serial stdio \ -nographic -monitor none -Stafford