Alan Cox wrote:
>On Maw, 2003-07-22 at 18:37, Jason Baron wrote:
>
>
>>>I tell init to re-execute itself (after pivot_root and thus from the new
>>>root fs), which causes init to close its old fds and open new ones from
>>>the new root fs with. This is necessary because init already runs as pid
>>>1 when I start the root fs switching. Maybe something changed with the
>>>kernel process fds from 2.4.21-rc2 to 2.4.21-ac4 ?
>>>
>>>
>>>
>>yes, see the addition of the unshare_files function in kernel/fork.c
>>
>>
>
>Shouldnt really have changed anything except for security exploits and
>threaded apps doing weird stuff. In normal situations the files count is
>one so we should actually be executing nothing more exciting that an
>atomic_inc/atomic_dec.
>
>I wonder what is going on here.
>
>-
>
>
But kernel threads may be incrementing init's files->count before user
space init execs, so unshare_files() after execve("/sbin/init") ends up
copying files.
--Mika
-
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/
This archive was generated by hypermail 2b29 : Wed Jul 23 2003 - 22:00:47 EST