I have the same issue, I have Maya 13 installed on a Lenovo Y560p with ATI Radeon 6570M Graphics. It is kworker and cinnamon consuming all the cpu resource, they take turns changing every few seconds in the 'top' command.
Even if I run the liveCD without the ATI drivers installed, the kworkers are still there sucking the CPU power. From this forum and other sites it seems to be a interrupt problem with ACPI and related to the Radeon graphics. I also have a Dell D630 Latitude with Nvidia graphics, and this runs fine.
I have tried disabling the ACPI in the grub config, disabling the ACPI in the ATI graphics card, updating the kernel, and headers (which causes the Cinnamon start menu to behave strangely), and still I have the same problem.
If anyone else has had some luck reducing or eliminating this, please share. I really like Mint/Cinnamon 13 and hope it gets fixed soon.