Xen devel - Sep 2013 - [PATCH v2] libxl: remove qemu default devices for upstream qemu

Remove default devices created by qemu. Qemu will create only devices
defined by xen, since the devices not defined by xen are not usable.
Remove deleting of empty floppy no more needed with nodefault.

Changes from v1:
Fix multi-line comment style

Signed-off-by: Fabio Fantoni <fabio.fantoni@m2r.biz>
---
 tools/libxl/libxl_dm.c |   10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/tools/libxl/libxl_dm.c b/tools/libxl/libxl_dm.c
index 2c6f5d9..eb71089 100644
--- a/tools/libxl/libxl_dm.c
+++ b/tools/libxl/libxl_dm.c
@@ -392,6 +392,13 @@ static char ** libxl__build_device_model_args_new(libxl__gc
*gc,
     flexarray_append(dm_args, "-mon");
     flexarray_append(dm_args, "chardev=libxl-cmd,mode=control");
 
+    /* 
+     * Remove default devices created by qemu. Qemu will create only devices
+     * defined by xen, since the devices not defined by xen are not usable.
+     * Remove deleting of empty floppy no more needed with nodefault.
+     */
+    flexarray_append(dm_args, "-nodefaults");
+
     if (b_info->type == LIBXL_DOMAIN_TYPE_PV) {
         flexarray_append(dm_args, "-xen-attach");
     }
@@ -457,9 +464,6 @@ static char ** libxl__build_device_model_args_new(libxl__gc
*gc,
     if (b_info->type == LIBXL_DOMAIN_TYPE_HVM) {
         int ioemu_nics = 0;
 
-        /* Disable useless empty floppy drive */
-        flexarray_vappend(dm_args, "-global",
"isa-fdc.driveA=", NULL);
-
         if (b_info->u.hvm.serial) {
             flexarray_vappend(dm_args, "-serial",
b_info->u.hvm.serial, NULL);
         }
-- 
1.7.9.5

Il 30/09/2013 13:53, Fabio Fantoni ha scritto:
> Remove default devices created by qemu. Qemu will create only devices
> defined by xen, since the devices not defined by xen are not usable.
> Remove deleting of empty floppy no more needed with nodefault.
Any comment on this?

Thanks for any reply.
>
> Changes from v1:
> Fix multi-line comment style
>
> Signed-off-by: Fabio Fantoni <fabio.fantoni@m2r.biz>
> ---
>   tools/libxl/libxl_dm.c |   10 +++++++---
>   1 file changed, 7 insertions(+), 3 deletions(-)
>
> diff --git a/tools/libxl/libxl_dm.c b/tools/libxl/libxl_dm.c
> index 2c6f5d9..eb71089 100644
> --- a/tools/libxl/libxl_dm.c
> +++ b/tools/libxl/libxl_dm.c
> @@ -392,6 +392,13 @@ static char **
libxl__build_device_model_args_new(libxl__gc *gc,
>       flexarray_append(dm_args, "-mon");
>       flexarray_append(dm_args,
"chardev=libxl-cmd,mode=control");
>   
> +    /*
> +     * Remove default devices created by qemu. Qemu will create only
devices
> +     * defined by xen, since the devices not defined by xen are not
usable.
> +     * Remove deleting of empty floppy no more needed with nodefault.
> +     */
> +    flexarray_append(dm_args, "-nodefaults");
> +
>       if (b_info->type == LIBXL_DOMAIN_TYPE_PV) {
>           flexarray_append(dm_args, "-xen-attach");
>       }
> @@ -457,9 +464,6 @@ static char **
libxl__build_device_model_args_new(libxl__gc *gc,
>       if (b_info->type == LIBXL_DOMAIN_TYPE_HVM) {
>           int ioemu_nics = 0;
>   
> -        /* Disable useless empty floppy drive */
> -        flexarray_vappend(dm_args, "-global",
"isa-fdc.driveA=", NULL);
> -
>           if (b_info->u.hvm.serial) {
>               flexarray_vappend(dm_args, "-serial",
b_info->u.hvm.serial, NULL);
>           }

On 10/08/2013 03:51 PM, Fabio Fantoni wrote:
> Il 30/09/2013 13:53, Fabio Fantoni ha scritto:
>> Remove default devices created by qemu. Qemu will create only devices
>> defined by xen, since the devices not defined by xen are not usable.
>> Remove deleting of empty floppy no more needed with nodefault.
>
> Any comment on this?
>
> Thanks for any reply.
It sounds like a good idea to me, but I''m not in a position to review 
it.  You should CC Anthony Perard along with Stefano for patches that 
have to do with qemu.

  -George
>
>>
>> Changes from v1:
>> Fix multi-line comment style
>>
>> Signed-off-by: Fabio Fantoni <fabio.fantoni@m2r.biz>
>> ---
>>   tools/libxl/libxl_dm.c |   10 +++++++---
>>   1 file changed, 7 insertions(+), 3 deletions(-)
>>
>> diff --git a/tools/libxl/libxl_dm.c b/tools/libxl/libxl_dm.c
>> index 2c6f5d9..eb71089 100644
>> --- a/tools/libxl/libxl_dm.c
>> +++ b/tools/libxl/libxl_dm.c
>> @@ -392,6 +392,13 @@ static char **
>> libxl__build_device_model_args_new(libxl__gc *gc,
>>       flexarray_append(dm_args, "-mon");
>>       flexarray_append(dm_args,
"chardev=libxl-cmd,mode=control");
>> +    /*
>> +     * Remove default devices created by qemu. Qemu will create only
>> devices
>> +     * defined by xen, since the devices not defined by xen are not
>> usable.
>> +     * Remove deleting of empty floppy no more needed with nodefault.
>> +     */
>> +    flexarray_append(dm_args, "-nodefaults");
>> +
>>       if (b_info->type == LIBXL_DOMAIN_TYPE_PV) {
>>           flexarray_append(dm_args, "-xen-attach");
>>       }
>> @@ -457,9 +464,6 @@ static char **
>> libxl__build_device_model_args_new(libxl__gc *gc,
>>       if (b_info->type == LIBXL_DOMAIN_TYPE_HVM) {
>>           int ioemu_nics = 0;
>> -        /* Disable useless empty floppy drive */
>> -        flexarray_vappend(dm_args, "-global",
"isa-fdc.driveA=", NULL);
>> -
>>           if (b_info->u.hvm.serial) {
>>               flexarray_vappend(dm_args, "-serial",
>> b_info->u.hvm.serial, NULL);
>>           }
>

On Tue, Oct 08, 2013 at 03:54:16PM +0100, George Dunlap
wrote:
> On 10/08/2013 03:51 PM, Fabio Fantoni wrote:
> >Il 30/09/2013 13:53, Fabio Fantoni ha scritto:
> >>Remove default devices created by qemu. Qemu will create only
devices
> >>defined by xen, since the devices not defined by xen are not
usable.
> >>Remove deleting of empty floppy no more needed with nodefault.
> >
> >Any comment on this?
> >
> >Thanks for any reply.
> 
> It sounds like a good idea to me, but I''m not in a position to
> review it.  You should CC Anthony Perard along with Stefano for
> patches that have to do with qemu.
After applying the patch, there is three things that goes away:
  - the parallel port
  - an empty cdrom driver, if xl does not ask for one
  - a block device reported by qemu as "sd0"

So, parallel, I suppose that can go away, as it''s not usubal (by
default
the output go to the graphic output). The "sd0" seems to be an sdcard
slot, but I don''t think we can use it from xl. And the last one, the
cdrom driver is also not usubal from xl, if one want to insert a cd into
it, the cdrom driver need to be in the vm config file.

So, I''m happy with the patch:

Acked-by: Anthony PERARD <anthony.perard@citrix.com>

-- 
Anthony PERARD

Il 10/10/2013 18:49, Anthony PERARD ha scritto:
> On Tue, Oct 08, 2013 at 03:54:16PM +0100, George Dunlap wrote:
>> On 10/08/2013 03:51 PM, Fabio Fantoni wrote:
>>> Il 30/09/2013 13:53, Fabio Fantoni ha scritto:
>>>> Remove default devices created by qemu. Qemu will create only
devices
>>>> defined by xen, since the devices not defined by xen are not
usable.
>>>> Remove deleting of empty floppy no more needed with nodefault.
>>> Any comment on this?
>>>
>>> Thanks for any reply.
>> It sounds like a good idea to me, but I''m not in a position to
>> review it.  You should CC Anthony Perard along with Stefano for
>> patches that have to do with qemu.
> After applying the patch, there is three things that goes away:
>    - the parallel port
>    - an empty cdrom driver, if xl does not ask for one
>    - a block device reported by qemu as "sd0"
>
> So, parallel, I suppose that can go away, as it''s not usubal (by
default
> the output go to the graphic output). The "sd0" seems to be an
sdcard
> slot, but I don''t think we can use it from xl. And the last one,
the
> cdrom driver is also not usubal from xl, if one want to insert a cd into
> it, the cdrom driver need to be in the vm config file.
>
> So, I''m happy with the patch:
>
> Acked-by: Anthony PERARD <anthony.perard@citrix.com>
>
Thanks for your reply, can you check also this post please?
http://lists.xen.org/archives/html/xen-devel/2013-10/msg00843.html

Anthony PERARD writes ("Re: [PATCH v2] libxl: remove qemu default devices
for upstream qemu"):
> On Tue, Oct 08, 2013 at 03:54:16PM +0100, George Dunlap wrote:
> > On 10/08/2013 03:51 PM, Fabio Fantoni wrote:
> > >Il 30/09/2013 13:53, Fabio Fantoni ha scritto:
> > >>Remove default devices created by qemu. Qemu will create only
devices
> > >>defined by xen, since the devices not defined by xen are not
usable.
> > >>Remove deleting of empty floppy no more needed with nodefault.
> > >
> > >Any comment on this?
> > >
> > >Thanks for any reply.
> > 
> > It sounds like a good idea to me, but I''m not in a position
to
> > review it.  You should CC Anthony Perard along with Stefano for
> > patches that have to do with qemu.
> 
> After applying the patch, there is three things that goes away:
>   - the parallel port
>   - an empty cdrom driver, if xl does not ask for one
>   - a block device reported by qemu as "sd0"
> 
> So, parallel, I suppose that can go away, as it''s not usubal (by
default
> the output go to the graphic output). The "sd0" seems to be an
sdcard
> slot, but I don''t think we can use it from xl. And the last one,
the
> cdrom driver is also not usubal from xl, if one want to insert a cd into
> it, the cdrom driver need to be in the vm config file.
> 
> So, I''m happy with the patch:
> 
> Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Thanks for the patch and the review.

Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>

Ian.