Accessing raw devices returned "Device or resource busy"

Issue

• Accessing raw device returned "Device or Resource busy" but reading the underlying device worked well.

# dd if=/dev/cciss/c0d2p1 of=/dev/null bs=4k count=1k
1024+0 records in
1024+0 records out
4194304 bytes (4.2 MB) copied, 0.046056 seconds, 91.1 MB/s

# /bin/raw /dev/raw/raw30 /dev/cciss/c0d2p1
/dev/raw/raw30: bound to major 104, minor 33

# dd if=/dev/raw/raw30 of=/dev/null bs=4k count=1k
dd: opening `/dev/raw/raw30': Device or resource busy