Re: [PATCH] missing chunk of HVM direct kernel boot patch

[Ian Campbell <Ian.Campbell@citrix.com>]

On Fri, 2014-11-28 at 13:55 +0800, Chunyan Liu wrote:
> Found by Stefano, this chunk of the patch was never applied to
> xen-unstable (commit 11dffa2359e8a2629490c14c029c7c7c777b3e47),
> see http://marc.info/?l=qemu-devel&m=140471493425353&w=2.

How strange, "git am" usually makes it pretty difficult to miss hunks.
Sorry about this.

> Signed-off-by: Chunyan Liu <cyliu@suse.com>

Acked-by: Ian Campbell <ian.campbell@citrix.com>

I'm afraid that despite the circumstances this still needs a release ack
from Konrad. Obviously the upside is fixing a partially implemented
feature, but I'm not sure what the downsides are.

Has this been tested with stubdoms, including when this feature is not
used? My biggest concern is that because this function is also used to
build the command line for the stubdom and the stubdom is PV and hence
has at least a ->kernel setting then this new code might break that use
case, by adding these options when they are not wanted. This path is all
a bit tangled so I'm not 100% sure if those fields are actually set or
not.

> ---
>  tools/libxl/libxl_dm.c | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/tools/libxl/libxl_dm.c b/tools/libxl/libxl_dm.c
> index 3e191c3..b25b574 100644
> --- a/tools/libxl/libxl_dm.c
> +++ b/tools/libxl/libxl_dm.c
> @@ -527,6 +527,15 @@ static char ** libxl__build_device_model_args_new(libxl__gc *gc,
>      if (b_info->type == LIBXL_DOMAIN_TYPE_HVM) {
>          int ioemu_nics = 0;
>  
> +        if (b_info->kernel)
> +            flexarray_vappend(dm_args, "-kernel", b_info->kernel, NULL);
> +
> +        if (b_info->ramdisk)
> +            flexarray_vappend(dm_args, "-initrd", b_info->ramdisk, NULL);
> +
> +        if (b_info->cmdline)
> +            flexarray_vappend(dm_args, "-append", b_info->cmdline, NULL);
> +
>          if (b_info->u.hvm.serial || b_info->u.hvm.serial_list) {
>              if ( b_info->u.hvm.serial && b_info->u.hvm.serial_list )
>              {