Modify efivars permisson denied

[Lucas Tanure]

Hi,

I would like to modify efivars at /sys/firmware/efi/efivars/.
But I can't modify it using root.

The file :
-rw-r--r-- 1 root root 31 Mar  4 19:04
/sys/firmware/efi/efivars/OilSetup-88d1911c-ab4a-4335-9e9a-26be9081acc3

the mount point :
efivarfs on /sys/firmware/efi/efivars type efivarfs
(rw,nosuid,nodev,noexec,relatime)

Any ideas ?
Thanks

-- 
Lucas Tanure