From: Li Zhijian <lizhijian@cn.fujitsu.com>
To: <linux-kernel@vger.kernel.org>,
Dominik Brodowski <linux@dominikbrodowski.net>,
Andrew Morton <akpm@linux-foundation.org>
Cc: <zhijianx.li@intel.com>, Philip Li <philip.li@intel.com>
Subject: Re: [PATCH] initramfs: clean old path before creating a hardlink
Date: Thu, 22 Nov 2018 09:55:22 +0800 [thread overview]
Message-ID: <2ac09b0f-2c26-3e19-1a33-f2d5ea1ae3ad@cn.fujitsu.com> (raw)
In-Reply-To: <1542352368-13299-1-git-send-email-lizhijian@cn.fujitsu.com>
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 <philip.li@intel.com>
> Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
> ---
> 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;
> }
next prev parent reply other threads:[~2018-11-22 1:55 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-11-16 7:12 [PATCH] initramfs: clean old path before creating a hardlink Li Zhijian
2018-11-22 1:55 ` Li Zhijian [this message]
2018-11-26 23:34 ` Andrew Morton
2018-11-27 4:04 ` Li Zhijian
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=2ac09b0f-2c26-3e19-1a33-f2d5ea1ae3ad@cn.fujitsu.com \
--to=lizhijian@cn.fujitsu.com \
--cc=akpm@linux-foundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux@dominikbrodowski.net \
--cc=philip.li@intel.com \
--cc=zhijianx.li@intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.