Re: Re[2]: mount -o remount,ro cause error "device is busy"

[Andreas Schwab <schwab@suse.de>]

Michael Cheung <vividy@justware.co.jp> writes:

|> hi,
|> 
|> maybe i am wrong, but I really can't find any other process runing.
|> 
|> my step is:
|> 1) "/" and "/usr" are busy
|> 2) shut down to single user mode
|> 3) "/" still busy
|> 4) "/usr" can be unmounted, but can't mount -o ro,remount /usr, show busy error.
|> 5) umount -a, after this, only /proc and / exist.
|> 6) mount -o ro,remount /, show busy error.
|> 
|> I have mentioned I have used "ps aux" to check the process list,
|> there are no user process left. except the following: (repost)
|> root         1  0.1  0.7  1056  484 ?        S    15:46   0:04 init [S] 
|> root         2  0.0  0.0     0    0 ?        SW   15:46   0:00 [keventd]
|> root         3  0.0  0.0     0    0 ?        SWN  15:46   0:00 [ksoftirqd_CPU0]
|> root         4  0.0  0.0     0    0 ?        SW   15:46   0:00 [kswapd]
|> root         5  0.0  0.0     0    0 ?        SW   15:46   0:00 [bdflush]
|> root         6  0.0  0.0     0    0 ?        SW   15:46   0:00 [kupdated]
|> root      1042  0.0  0.7  1056  484 tty1     S    16:33   0:00 init [S] 
|> root      1043  0.6  1.5  1840 1004 tty1     S    16:33   0:00 /bin/sh
|> root      1045  0.0  1.0  2260  680 tty1     R    16:33   0:00 ps aux
|> 
|> and I also checked by fuser -v /usr,
|> only used by kernel.
|> and fuser -c /, show many process list above.
|> 
|> If i have a mistake, would you like to tell me where is the mistake?

Check for references to deleted files (/proc/*/fd).  "init u" should help.

Andreas.

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Andreas Schwab, SuSE Labs, schwab@suse.de
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