[Libguestfs] [PATCH 5/8] v2v: linux: check also kernel config for modules

When checking whether a kernel supports virtio or it is Xen-based, it is assumed that the feature has the kernel module for it; this will fail if the feature is built-in in the kernel, misrepresenting it. The solution is to check the kernel configuration (/boot/config-$kver) whether the feature is built-in, in case there is no module available. This fixes the virtio detection on Ubuntu kernels, where virtio is built in and not as module. --- v2v/convert_linux.ml | 22 ++++++++++++++++++++-- 1 file changed, 20 insertions(+), 2 deletions(-) diff --git a/v2v/convert_linux.ml b/v2v/convert_linux.ml index acc91dc..6ca7cdb 100644 --- a/v2v/convert_linux.ml +++ b/v2v/convert_linux.ml @@ -125,6 +125,21 @@ let rec convert ~keep_serial_console (g : G.guestfs) inspect source rcaps = (* What kernel/kernel-like packages are installed on the current guest? *) let installed_kernels : kernel_info list = let rex_ko = Str.regexp ".*\\.k?o\\(\\.xz\\)?$" in + let check_config version feature = + let prefix = "^CONFIG_" ^ String.uppercase_ascii feature ^ "=" in + let lines = g#grep ~extended:true prefix ("/boot/config-" ^ version) in + let lines = Array.to_list lines in + match lines with + | [] -> false + | line :: _ -> + let kind = snd (String.split "=" line) in + (match kind with + | "m" (* Theoretically this should not be needed, since the module + * would be found. *) + | "y" -> true + | _ -> false + ) + in let rex_ko_extract = Str.regexp ".*/\\([^/]+\\)\\.k?o\\(\\.xz\\)?$" in let rex_initrd = Str.regexp "^initr\\(d\\|amfs\\)-.*\\(\\.img\\)?$" in filter_map ( @@ -223,8 +238,11 @@ let rec convert ~keep_serial_console (g : G.guestfs) inspect source rcaps = ) modules in assert (List.length modules > 0); - let supports_virtio = List.mem "virtio_net" modules in - let is_xen_kernel = List.mem "xennet" modules in + let kernel_supports what = + List.mem what modules || check_config version what in + + let supports_virtio = kernel_supports "virtio_net" in + let is_xen_kernel = kernel_supports "xennet" in (* If the package name is like "kernel-debug", then it's * a debug kernel. -- 2.7.4