Starting with the Oracle Unbreakable Enterprise Linux Kernel (UEK) the ASMlib drivers are now included in the kernel. This means that updating the kernel does not require installing the appropriate kernel modules as well.
In addition to the kernel modules you need the following packages:
For Oracle Enterprise Linux “oracleasm-support” can be found on the installation media while “oracleasmlib” is not available on the installation media. “oracleasmlib” can be downloaded over the ULN network (more information here).
If you dont have a ULN account or using Red Hat you can get the freely available packages (for OEL and Red Hat) here.