Re: [Qemu-devel] [PATCH 2/2] libxl: introduce gfx_passthru_kind

["Chen, Tiejun" <tiejun.chen@intel.com>]

On 2015/3/6 20:59, Wei Liu wrote:
> On Fri, Mar 06, 2015 at 05:18:36PM +0800, Chen, Tiejun wrote:
>> On 2015/3/6 17:08, Tiejun Chen wrote:
>>> Although we already have 'gfx_passthru' in b_info, this doesn' suffice
>>> after we want to handle IGD specifically. Now we define a new field of
>>> type, gfx_passthru_kind, to indicate we're trying to pass IGD. Actually
>>> this means we can benefit this to support other specific devices just
>>> by extending gfx_passthru_kind. And then we can cooperate with
>>> gfx_passthru to address IGD cases as follows:
>>>
>>>      gfx_passthru = 0    => sets build_info.u.gfx_passthru to false
>>>      gfx_passthru = 1    => sets build_info.u.gfx_passthru to false and
>>>                             build_info.u.gfx_passthru_kind to DEFAULT
>>>      gfx_passthru = "igd"    => sets build_info.u.gfx_passthru to false
>>>                                 and build_info.u.gfx_passthru_kind to IGD
>>>
>>> Here if gfx_passthru_kind = DEFAULT, we will call
>>> libxl__is_igd_vga_passthru() to check if we're hitting that table to need
>>> to pass that option to qemu. But if gfx_passthru_kind = "igd" we always
>>> force to pass that.
>>>
>>> Signed-off-by: Tiejun Chen <tiejun.chen@intel.com>
>>> ---
>>>   tools/libxl/libxl_dm.c      | 13 +++++++++++++
>>>   tools/libxl/libxl_types.idl |  6 ++++++
>>>   tools/libxl/xl_cmdimpl.c    | 19 +++++++++++++++++--
>>>   3 files changed, 36 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/tools/libxl/libxl_dm.c b/tools/libxl/libxl_dm.c
>>> index 8599a6a..780dd2a 100644
>>> --- a/tools/libxl/libxl_dm.c
>>> +++ b/tools/libxl/libxl_dm.c
>>
>> Sorry, looks I'm missing to remove '-gfx_passthru' since this should be gone
>> in the case of qemu upstream,
>>
>> @@ -710,9 +710,6 @@ static char **
>> libxl__build_device_model_args_new(libxl__gc *gc,
>>               flexarray_append(dm_args, "-net");
>>               flexarray_append(dm_args, "none");
>>           }
>> -        if (libxl_defbool_val(b_info->u.hvm.gfx_passthru)) {
>> -            flexarray_append(dm_args, "-gfx_passthru");
>> -        }
>>       } else {
>>           if (!sdl && !vnc) {
>>               flexarray_append(dm_args, "-nographic");
>>
>> I will fold this into next revision after this review.
>>
>
> I think this change alone warrants a separate changeset. It should be
> patch 0 of your series as a preparatory patch. Please remember to
> elaborate in commit message why that hunk is not needed in upstream
> QEMU.
>

What about this?

"-gfx_passthru" is just introduced to work for qemu-xen-traditional so 
we should get this away from libxl__build_device_model_args_new() in the 
case of qemu upstream.

Thanks
Tiejun