Does overlay driver work if built in to the kernel?

[Keyon Jie <yang.jie@xxxxxxxxxxxxxxx>]

Hi all,

Sorry for annoys in case the mail is sent twice, it looks to me it was 
moderated that the previous one was sent before subscribing the mailing 
list.


I am new to the overlayfs, I am hitting issues to make kernel modules 
work in a container environment where the Kubernetes feature really need 
the overlayfs support.


I figured out to make overlay driver built-in to the VM kernel (and then 
shared to the container), but looks like the Kubernetes always fail when 
trying to create overlayfs mounts, with errors like 'permission denied'.


I am seeing that overlay driver is released with modular 
(CONFIG_OVERLAY_FS=m) in most (not sure if it is all) Linux 
distributions, so I am wondering if the overlay driver work when built 
in to the kernel?


Thanks,

~Keyon