lkml.org 
[lkml]   [2002]   [Mar]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: chroot_fs_refs and pivot_root question
Amazing that nobody knew the answer but I think I understand now the
reason, the /proc/1/cwd and /proc/1/root point to "/" and the comment
above sys_pivot_root says:

* Note:
* - we don't move root/cwd if they are not at the root (reason: if
something
* cared enough to change them, it's probably wrong to force them
elsewhere)

So, that is why the /sbin/init wasn't moved, because it's root/cwd were at
/initrd so when it got pivoted to / (and / put to /sysroot) the init was
left alone. Well, either the above policy is wrong or I need to figure out
a way to convince init to move peacebly where I want it to... :)

On Wed, 6 Mar 2002, Tigran Aivazian wrote:

> Hello,
>
> Looking at (2.4.9's) sys_pivot_root() implementation I can see that it
> moves all the processes' root/pwd references from the old root to the new
> one.
>
> However, somehow /sbin/init managed to survive the move and is keeping the
> filesystem busy:
>
> # lsof /sysroot
> COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME
> init 1 0 txt REG 22,65 28220 11217 /sysroot/sbin/init
> init 1 0 mem REG 22,65 468849 10376
> /sysroot/lib/ld-2.2.2.so
> init 1 0 mem REG 22,65 5636080 10370
> /sysroot/lib/i686/libc-2.2.2.so
>
> # cat /proc/1/maps
> 08048000-0804f000 r-xp 00000000 16:41 11217 /sysroot/sbin/init
> 0804f000-08050000 rw-p 00006000 16:41 11217 /sysroot/sbin/init
> 08050000-08054000 rwxp 00000000 00:00 0
> 15556000-1556c000 r-xp 00000000 16:41 10376 /sysroot/lib/ld-2.2.2.so
> 1556c000-1556d000 rw-p 00015000 16:41 10376 /sysroot/lib/ld-2.2.2.so
> 1556d000-1556e000 rw-p 00000000 00:00 0
> 15573000-15699000 r-xp 00000000 16:41 10370 /sysroot/lib/i686/libc-2.2.2.so
> 15699000-1569f000 rw-p 00125000 16:41 10370 /sysroot/lib/i686/libc-2.2.2.so
> 1569f000-156a3000 rw-p 00000000 00:00 0
> 3fffe000-40000000 rwxp fffff000 00:00 0
>
> Any clues why and how to force it to exec a binary on the new root (or
> get rid of it in any other way)?
>
> Regards,
> Tigran
>
>
>
>

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:24    [W:0.045 / U:0.240 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site