Re: [Libguestfs] [PATCH v2 3/3] 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 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/linux_kernels.ml | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/v2v/linux_kernels.ml b/v2v/linux_kernels.ml index df093d0..f15e82a 100644 --- a/v2v/linux_kernels.ml +++ b/v2v/linux_kernels.ml @@ -55,6 +55,21 @@ let detect_kernels (g : G.guestfs) inspect family bootloader = (* 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\\)?$" in + let check_config version feature = function + | None -> false + | Some config -> + let prefix = "^CONFIG_" ^ String.uppercase_ascii feature ^ "=" in + let lines = g#grep ~extended:true prefix config in + let lines = Array.to_list lines in + match lines with + | [] -> false + | line :: _ -> + let kind = snd (String.split "=" line) in + (match kind with + | "m" | "y" -> true + | _ -> false + ) + in let rex_ko_extract = Str.regexp ".*/\\([^/]+\\)\\.k?o\\(\\.xz\\)?$" in let rex_initrd = if family = `Debian_family then @@ -163,7 +178,11 @@ let detect_kernels (g : G.guestfs) inspect family bootloader = if List.mem cfg files then Some cfg else None in - let supports_virtio = List.mem "virtio_net" modules in + let kernel_supports what kconf = + List.mem what modules + || check_config version kconf config_file in + + let supports_virtio = kernel_supports "virtio_net" "VIRTIO_NET" in let is_xen_kernel = List.mem "xennet" modules in (* If the package name is like "kernel-debug", then it's --