我apt-get dist-upgrade今天（2016/02/01）做了一次，现在我的系统无法启动。
我能进入的唯一原因是还安装了 Ubuntu 的副本，并且我可以从 BIOS 启动它。 update-grub 已重新配置其引导加载程序以正确加载 debian 系统。
但是当我尝试从 Debian 安装 grub 时：
root@dell-3537:/home/john# grub-install
Installing for x86_64-efi platform.
efibootmgr: Could not set variable Boot0002: No such file or directory
efibootmgr: Could not prepare boot variable: No such file or directory
Installation finished. No error reported.
看起来好像找不到该grubx64.efi文件。如果我直接问efi是怎么回事，它似乎没有添加自己：
root@dell-3537:/home/john# efibootmgr -v
BootCurrent: 0004
Timeout: 0 seconds
BootOrder: 0004,0005,2003,2001,2002
Boot0000* UEFI Onboard LAN IPv4 ACPI(a0341d0,0)PCI(1c,0)PCI(0,0)MAC(MAC(ecf4bb93e02e,0)RC
Boot0001* UEFI Onboard LAN IPv6 ACPI(a0341d0,0)PCI(1c,0)PCI(0,0)MAC(MAC(ecf4bb93e02e,0)030d3c000000000000000000000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000RC
Boot0004* Ubuntu HD(1,800,fa000,6edd2bfd-b6c6-46e9-9413-d332f1333788)File(\EFI\ubuntu\grubx64.efi)RC
Boot0005* Windows Boot Manager HD(1,800,fa000,6edd2bfd-b6c6-46e9-9413-d332f1333788)File(\EFI\Microsoft\Boot\bootmgfw.efi)WINDOWS.........x...B.C.D.O.B.J.E.C.T.=.{.9.d.e.a.8.6.2.c.-.5.c.d.d.-.4.e.7.0.-.a.c.c.1.-.f.3.2.b.3.4.4.d.4.7.9.5.}...e...............
Boot0007* CD/DVD/CD-RW Drive BIOS(3,500,00)................-.L.......L............................................
Boot2001* EFI USB Device RC
Boot2002* EFI DVD/CDROM RC
Boot2003* EFI Network RC
谁能告诉我发生了什么事吗？