Для экономии места на корневом разделе решил вынести папку /usr/portage в хомяк и сделать симлинк:
$ ls -l /usr/po*
lrwxrwxrwx 1 root root 22 лис 9 17:36 /usr/portage -> /home/keed/bin/portage
receiving incremental file list
rsync: ERROR: cannot stat destination "/home/keed/bin/portage/distfiles/vbox-kernel-module-src-4.2.0.tar.xz": Permission denied (13)
rsync error: errors selecting input/output files, dirs (code 3) at main.c(565) [Receiver=3.0.9]
>>> Downloading 'http://ftp.gentoo.bg/distfiles/vbox-kernel-module-src-4.2.0.tar.xz'
/home/keed/bin/portage/distfiles/vbox-kernel-module-src-4.2.0.tar.xz: Permission denied
>>> Downloading 'http://ftp.cc.uoc.gr/mirrors/linux/gentoo/distfiles/vbox-kernel-module-src-4.2.0.tar.xz'
/home/keed/bin/portage/distfiles/vbox-kernel-module-src-4.2.0.tar.xz: Permission denied
>>> Downloading 'ftp://ftp.cc.uoc.gr/mirrors/linux/gentoo/distfiles/vbox-kernel-module-src-4.2.0.tar.xz'
/home/keed/bin/portage/distfiles/vbox-kernel-module-src-4.2.0.tar.xz: Permission denied
>>> Downloading 'http://dev.gentoo.org/~polynomial-c/virtualbox/vbox-kernel-module-src-4.2.0.tar.xz'
/home/keed/bin/portage/distfiles/vbox-kernel-module-src-4.2.0.tar.xz: Permission denied
!!! Couldn't download 'vbox-kernel-module-src-4.2.0.tar.xz'. Aborting.
* Fetch failed for 'app-emulation/virtualbox-modules-4.2.0-r1', Log file:
* '/var/tmp/portage/app-emulation/virtualbox-modules-4.2.0-r1/temp/build.log'
>>> Failed to emerge app-emulation/virtualbox-modules-4.2.0-r1, Log file:
>>> '/var/tmp/portage/app-emulation/virtualbox-modules-4.2.0-r1/temp/build.log'
* Messages for package app-emulation/virtualbox-modules-4.2.0-r1:
* Fetch failed for 'app-emulation/virtualbox-modules-4.2.0-r1', Log file:
* '/var/tmp/portage/app-emulation/virtualbox-modules-4.2.0-r1/temp/build.log'
P.S. В Gentoo новичек, не сочтите за идиота.