v2: Rich, I hope I've done all modifications according to your comments, namely: * moved the code from linux_bootloaders to convert_linux * made minor code modifications --- Not all UEFI guests can survive conversion, because of lost bootloader information in UEFI NVRAM. But some guest can cope with this because they have a fallback bootloader and use UEFI Removable Media Boot Behavior to load (see https://uefi.org/sites/default/files/resources/UEFI_Spec_2_8_A_Feb14.pdf 3.5.1.1 Removable Media Boot Behavior). If UEFI firmware can't find a bootloader in its settings it uses the removable media boot behavior to find a bootloader. We can fix the guests which don't have such a fallback loader by providing a temporary one. This bootloader is used for the first boot only, then the conversion script restores the initial bootloader settings and removes the temporary loader. Signed-off-by: Denis Plotnikov <dplotnikov(a)virtuozzo.com&gt; --- v2v/convert_linux.ml | 123 ++++++++++++++++++++++++++++++++++++++ v2v/linux_bootloaders.ml | 7 +++ v2v/linux_bootloaders.mli | 4 ++ 3 files changed, 134 insertions(+) diff --git a/v2v/convert_linux.ml b/v2v/convert_linux.ml index e91ae120f..045afa98b 100644 --- a/v2v/convert_linux.ml +++ b/v2v/convert_linux.ml @@ -1122,6 +1122,129 @@ shutdown -h -P +0 Linux.augeas_reload g ); + (* Some linux uefi setups can't boot after conversion because of + lost uefi boot entries. The uefi boot entries are stored in uefi + NVRAM. The NVRAM content isn't a part of vm disk content and + usualy can't be converted alongside the vm. + If a vm doesn't have uefi fallback path (/EFI/BOOT/BOOT<arch>.efi) + the vm is unbootable after conversion. + The following code tries to make an uefi fallback path for + a uefi linux vm. + *) + match inspect.i_firmware with + | I_UEFI _ -> ( + (* Standard uefi fallback path *) + let uefi_fallback_path = "/boot/efi/EFI/BOOT/" in + + (* Helper function checks if 'source' contains 's' *) + let contains source s = ( + let re = Str.regexp_string s in + try + ignore (Str.search_forward re source 0); + true + with Not_found -> false + ) in + + let cant_fix_uefi () = + info (f_"Can't fix UEFI bootloader. VM may not boot.") + in + + let get_uefi_arch_suffix = function + | "x86_64" -> Some "X64" + | "x86_32" -> Some "X32" + | _ -> None + in + + match get_uefi_arch_suffix inspect.i_arch with + | None -> cant_fix_uefi () + | Some suffix -> ( + let uefi_fallback_name = + sprintf "%sBOOT%s.EFI" uefi_fallback_path suffix in + + let file_exists file = + if g#exists file then + true + else ( + info (f_"Can't find file: '%s' needed for UEFI fixing") + file; + false ) + in + + let grub_config = bootloader#get_config_file () in + + let grub_path = + String.sub grub_config 0 (String.rindex grub_config '/') in + + if g#exists uefi_fallback_name then + (* don't do anything if uefi fallback exists *) + () + else ( + info (f_"Fixing UEFI bootloader."); + match inspect.i_distro, inspect.i_major_version with + | "centos", 6 -> + (* to make a bootable uefi centos 6 we need to + * copy grub.efi and grub.conf to UEFI fallback path + * and rename them to BOOT<arch>.efi and BOOT<arch>.conf + * correspondingly *) + let uefi_grub_name = String.concat "" [grub_path; "/grub.efi"] in + let uefi_grub_conf = String.concat "" [ + String.sub uefi_fallback_name 0 + (String.rindex uefi_fallback_name '.'); + ".conf" ] in + if file_exists uefi_grub_name && file_exists grub_config then ( + g#mkdir_p uefi_fallback_path; + g#cp uefi_grub_name uefi_fallback_name; + g#cp grub_config uefi_grub_conf; + let fix_script = sprintf +"#!/bin/bash +efibootmgr -c -L \"CentOS 6\" +rm -rf %s" uefi_fallback_path in + Firstboot.add_firstboot_script + g inspect.i_root "fix uefi boot" fix_script) + else + cant_fix_uefi () + | "ubuntu", 14 -> + (* to make a bootable uefi ubuntu 14 we need to + * copy shim<arch>.efi to UEFI fallback path + * and rename it to BOOT<arch>.efi, also we copy + * grub.efi and grub.cfg to UEFI fallback path without renaming *) + let arch_suffix = String.lowercase_ascii suffix in + + let shim = + String.concat "" [grub_path; "/shim"; arch_suffix; ".efi"] in + let uefi_grub_name = + String.concat "" [grub_path; "/grub"; arch_suffix; ".efi"] in + + if file_exists shim && file_exists uefi_grub_name + && file_exists grub_config then ( + g#mkdir_p uefi_fallback_path; + g#cp shim uefi_fallback_name; + g#cp uefi_grub_name uefi_fallback_path; + g#cp grub_config uefi_fallback_path; + (* if the shim is at the standard path, clean up uefi fixing + * if not, then just don't clean up and leave the temp loader + * at UEFI fallback path for simplicity + *) + if contains shim "/boot/efi/EFI/ubuntu/shim" then + let fix_script = sprintf +"#!/bin/bash +sudo efibootmgr -c -L ubuntu -l \\\\EFI\\\\ubuntu\\\\shim%s.efi +rm -rf %s" arch_suffix uefi_fallback_path in + Firstboot.add_firstboot_script + g inspect.i_root "fix uefi boot" fix_script + else + ()) + else + cant_fix_uefi () + | _, _ -> + info (f_"No UEFI fix rule for %s %d") + inspect.i_distro inspect.i_major_version; + cant_fix_uefi () + ) + ) + ) + | I_BIOS -> (); + (* Delete blkid caches if they exist, since they will refer to the old * device names. blkid will rebuild these on demand. * diff --git a/v2v/linux_bootloaders.ml b/v2v/linux_bootloaders.ml index de3d107e9..4ca28782b 100644 --- a/v2v/linux_bootloaders.ml +++ b/v2v/linux_bootloaders.ml @@ -36,6 +36,7 @@ class virtual bootloader = object method virtual configure_console : unit -> unit method virtual remove_console : unit -> unit method update () = () + method virtual get_config_file : unit -> string end (* Helper function for SUSE: remove (hdX,X) prefix from a path. *) @@ -184,6 +185,9 @@ object loop paths; g#aug_save () + + method get_config_file () = + grub_config end (** The method used to get and set the default kernel in Grub2. *) @@ -342,6 +346,9 @@ object (self) method update () = ignore (g#command [| grub2_mkconfig_cmd; "-o"; grub_config |]) + + method get_config_file () = + grub_config end (* Helper type used in detect_bootloader. *) diff --git a/v2v/linux_bootloaders.mli b/v2v/linux_bootloaders.mli index 30cdfe3c7..d9f0be8e1 100644 --- a/v2v/linux_bootloaders.mli +++ b/v2v/linux_bootloaders.mli @@ -44,6 +44,10 @@ class virtual bootloader : object (** Update the bootloader: For grub2 only this runs the [grub2-mkconfig] command to rebuild the configuration. This is not necessary for grub-legacy. *) + + method virtual get_config_file : unit -> string + (** Returns the path to the bootloader config file, + e.g /boot/grub/grub.cfg *) end (** Encapsulates a Linux boot loader as object. *) -- 2.17.0