I just discovered a workaround, courtesy of bug 656745 comment 0. This is what it said:
in /etc/default/grub change: GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" to GRUB_CMDLINE_LINUX_DEFAULT="quiet splash pcie_aspm=off" and run "sudo update-grub"
I just discovered a workaround, courtesy of bug 656745 comment 0. This is what it said:
in /etc/default/grub change: LINUX_DEFAULT= "quiet splash" LINUX_DEFAULT= "quiet splash pcie_aspm=off"
GRUB_CMDLINE_
to
GRUB_CMDLINE_
and run "sudo update-grub"