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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 5D413C43610 for ; Thu, 22 Nov 2018 01:55:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EBD1D20821 for ; Thu, 22 Nov 2018 01:55:30 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EBD1D20821 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=cn.fujitsu.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2403922AbeKVMcc (ORCPT ); Thu, 22 Nov 2018 07:32:32 -0500 Received: from mail.cn.fujitsu.com ([183.91.158.132]:8369 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1730718AbeKVMcb (ORCPT ); Thu, 22 Nov 2018 07:32:31 -0500 X-IronPort-AV: E=Sophos;i="5.43,368,1503331200"; d="scan'208";a="48531308" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 22 Nov 2018 09:55:26 +0800 Received: from G08CNEXCHPEKD03.g08.fujitsu.local (unknown [10.167.33.85]) by cn.fujitsu.com (Postfix) with ESMTP id 1098D4B714DF; Thu, 22 Nov 2018 09:55:26 +0800 (CST) Received: from [10.167.226.45] (10.167.226.45) by G08CNEXCHPEKD03.g08.fujitsu.local (10.167.33.89) with Microsoft SMTP Server id 14.3.408.0; Thu, 22 Nov 2018 09:55:32 +0800 Subject: Re: [PATCH] initramfs: clean old path before creating a hardlink To: , Dominik Brodowski , Andrew Morton CC: , Philip Li References: <1542352368-13299-1-git-send-email-lizhijian@cn.fujitsu.com> From: Li Zhijian Organization: fnst-ulinux Message-ID: <2ac09b0f-2c26-3e19-1a33-f2d5ea1ae3ad@cn.fujitsu.com> Date: Thu, 22 Nov 2018 09:55:22 +0800 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: <1542352368-13299-1-git-send-email-lizhijian@cn.fujitsu.com> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-Originating-IP: [10.167.226.45] X-yoursite-MailScanner-ID: 1098D4B714DF.AF756 X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: lizhijian@cn.fujitsu.com Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ping This patch is to fix initrd cannot be extracted properly in some cases. Thanks On 11/16/2018 03:12 PM, Li Zhijian wrote: > Previously, sys_link() will fail due to the new path is already existed. > this case ofen appears when we use a concated initrd, below is an > sample: > > 1) prepare a basic rootfs, it contains a regular files rc.local > lizhijian@:~/yocto-tiny-i386-2016-04-22$ cat etc/rc.local > #!/bin/sh > echo "Running /etc/rc.local..." > yocto-tiny-i386-2016-04-22$ find . | sed 's,^\./,,' | cpio -o -H newc | gzip -n -9 >../rootfs.cgz > > 2) create a extra initrd which also includes a etc/rc.local > lizhijian@:~/lkp-x86_64/etc$ echo "append initrd" >rc.local > lizhijian@:~/lkp/lkp-x86_64/etc$ cat rc.local > append initrd > lizhijian@:~/lkp/lkp-x86_64/etc$ ln rc.local rc.local.hardlink > append initrd > lizhijian@:~/lkp/lkp-x86_64/etc$ stat rc.local rc.local.hardlink > File: 'rc.local' > Size: 14 Blocks: 8 IO Block: 4096 regular file > Device: 801h/2049d Inode: 11296086 Links: 2 > Access: (0664/-rw-rw-r--) Uid: ( 1002/lizhijian) Gid: ( 1002/lizhijian) > Access: 2018-11-15 16:08:28.654464815 +0800 > Modify: 2018-11-15 16:07:57.514903210 +0800 > Change: 2018-11-15 16:08:24.180228872 +0800 > Birth: - > File: 'rc.local.hardlink' > Size: 14 Blocks: 8 IO Block: 4096 regular file > Device: 801h/2049d Inode: 11296086 Links: 2 > Access: (0664/-rw-rw-r--) Uid: ( 1002/lizhijian) Gid: ( 1002/lizhijian) > Access: 2018-11-15 16:08:28.654464815 +0800 > Modify: 2018-11-15 16:07:57.514903210 +0800 > Change: 2018-11-15 16:08:24.180228872 +0800 > Birth: - > > lizhijian@:~/lkp/lkp-x86_64$ find . | sed 's,^\./,,' | cpio -o -H newc | gzip -n -9 >../rc-local.cgz > lizhijian@:~/lkp/lkp-x86_64$ gzip -dc ../rc-local.cgz | cpio -t > . > etc > etc/rc.local.hardlink <<< it will be extracted first at this initrd > etc/rc.local > > 3) concate 2 initrds and boot > lizhijian@:~/lkp$ cat rootfs.cgz rc-local.cgz >concate-initrd.cgz > lizhijian@:~/lkp$ qemu-system-x86_64 -nographic -enable-kvm -cpu host -smp 1 -m 1024 -kernel ~/lkp/linux/arch/x86/boot/bzImage -append "console=ttyS0 earlyprint=ttyS0 ignore_loglevel" -initrd ./concate-initr.cgz -serial stdio -nodefaults > > In this case, sys_link(2) will fail and return -EEXIST, so we can only > get the rc.local at rootfs.cgz instead of rc-local.cgz > > CC: Philip Li > Signed-off-by: Li Zhijian > --- > init/initramfs.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/init/initramfs.c b/init/initramfs.c > index 6405577..381fd4c 100644 > --- a/init/initramfs.c > +++ b/init/initramfs.c > @@ -291,12 +291,16 @@ static int __init do_reset(void) > return 1; > } > > +static void __init clean_path(char *path, umode_t fmode); > + > static int __init maybe_link(void) > { > if (nlink >= 2) { > char *old = find_link(major, minor, ino, mode, collected); > - if (old) > + if (old) { > + clean_path(collected, 0); > return (ksys_link(old, collected) < 0) ? -1 : 1; > + } > } > return 0; > }