rd.o module refcount problem

rd.o module refcount problem

[Maneesh Soni]

The module ref count for rd.o module is not adjusted and remains 1 while doing 
the following things. 

[root@llm01 mod]# insmod /sdb/linux-2.5.70/drivers/block/rd.o
[root@llm01 mod]# lsmod
Module                  Size  Used by
rd                      5568  0 - Live 0xf88b5000
[root@llm01 mod]# mkfs -t ext2 /dev/ram0
.
.
[root@llm01 mod]# lsmod
Module                  Size  Used by
rd                      5568  1 - Live 0xf88b5000

mount/umount of /dev/ram0 does not change the rd.o module ref count. 

So, who is supposed to release the rd.o module gracefully? 
Also mount /dev/ram0 should hold a ref and umount should release the same.

Same test on 2.4.20 looks correct and mount increments the ref count and
umount decrements the ref count.

Regards,
Maneesh

-- 
Maneesh Soni
IBM Linux Technology Center, 
IBM India Software Lab, Bangalore.
Phone: +91-80-5044999 email: maneesh@in.ibm.com
http://lse.sourceforge.net/

Re: rd.o module refcount problem

[Russell King]

On Thu, May 29, 2003 at 03:55:10PM +0530, Maneesh Soni wrote:
> The module ref count for rd.o module is not adjusted and remains 1 while
> doing the following things. 
> 
> [root@llm01 mod]# insmod /sdb/linux-2.5.70/drivers/block/rd.o
> [root@llm01 mod]# lsmod
> Module                  Size  Used by
> rd                      5568  0 - Live 0xf88b5000
> [root@llm01 mod]# mkfs -t ext2 /dev/ram0
> .
> .
> [root@llm01 mod]# lsmod
> Module                  Size  Used by
> rd                      5568  1 - Live 0xf88b5000
> 
> mount/umount of /dev/ram0 does not change the rd.o module ref count. 
> 
> So, who is supposed to release the rd.o module gracefully? 
> Also mount /dev/ram0 should hold a ref and umount should release the same.
> 
> Same test on 2.4.20 looks correct and mount increments the ref count and
> umount decrements the ref count.

I think you'll find you have to tell the ramdisk to invalidate its contents
before the module count drops.

-- 
Russell King (rmk@arm.linux.org.uk)                The developer of ARM Linux
             http://www.arm.linux.org.uk/personal/aboutme.html