VMware VM Kernel Panic - not syncing, Unable to access resume device

Issue

• We have upgraded OS version from RHEL 5.5 to 5.9 after then we have rebooted the server. But we are getting kernel panic error

1 Unable to access resume device (LABEL=SWAP-sda2)
2 Mount could not find file system '/dev/root'
3 setuproot: moving /dev failed no such file or directory.

• But when we have rebooted the server through old kernel version kernel panic error not coming & system rebooted.