question on pivot_root and kernel threads

question on pivot_root and kernel threads

[Chris Friesen]

I've got an embedded system that we're trying to move from 2.4.18 to 
2.4.22 (which involves a userspace upgrade as well).  It netboots with 
an initrd, and then at startup converts it to a tmpfs, unmounts the 
original ramdisk, and frees the memory.

With 2.4.22 suddenly it started complaining about being unable to 
unmount the original ramdisk.  After some digging, it seems that the 
kernel threads (keventd, ksoftirqd_CPU0, kswapd, bdflush, kupdated, and 
mtdblockd) are starting up with stdin/stdout/stderr set to /dev/console 
in the original ramdisk.  When I do the pivot_root so that the original 
ramdisk is mounted at "/mnt", I end up with a bunch of references to 
"/mnt/dev/console", and I can't unmount "/mnt" since the refcount is 
nonzero.

At a guess, its related to this thread:

http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&selm=hpYn.1fz.21%40gated-at.bofh.it

Did this ever get resolved properly?


Thanks,

Chris


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Chris Friesen                    | MailStop: 043/33/F10
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