btrfs unknown token device on boot after upgrade to kernel 5.1.15

[javashin]

hello i updated the kernel to 5.1.15 and now when i generate a initrramfs with genkernel --btrfs ramdisk i got "btrfs unknown token device on boot" every time i boot , but its boots ok im on gentoo using genkernel-next 70

[javashin]

when i generate a initramfs with genkernel ramdisk only this dont happen thanks in advance