efix IY90945 fixes a VIOS hang. The problem was 
discovered when backing up Linux with a tool 
name rsync.

The hang can occur when loading the Linux client
vscsi load module.

To install this fix do the following:
1.ftp the fix to your VIO server, you will find the package
  at ftp://ftp.software.ibm.com/aix/efixes/iy90945
2.at the command line run "oem_setup_env
3.at the root prompt run "cd /home/padmin"
4.at the root prompt run "emgr -e IY90945.epkg.Z"

This efix has one file in it, vscsi_host.