Re: [Qemu-devel] [PATCH RFC v3 for-2.9 08/11] rbd: Revert -blockdev and -drive parameter auth-supported

[Markus Armbruster <armbru@redhat.com>]

Eric Blake <eblake@redhat.com> writes:

> On 03/27/2017 08:26 AM, Markus Armbruster wrote:
>> This reverts half of commit 0a55679.  We're having second thoughts on
>> the QAPI schema (and thus the external interface), and haven't reached
>> consensus, yet.  Issues include:
>> 
>
>> Let's avoid painting ourselves into a corner now, and revert the
>> feature for 2.9.
>> 
>> Note that users can still configure authentication methods with a
>> configuration file.  They probably do that anyway if they use Ceph
>> outside QEMU as well.
>
> If we're only reverting the QMP blockdev-add feature, then this makes
> absolute sense (it's not a regression since we don't have a release with
> it yet, and we don't want to bake something into the release that can't
> be supported).  But breaking -drive usage seems risky, especially since
> libvirt is already expecting to work - I'm worried that doing this may
> break existing libvirt command line usage if the QemuOpts side doesn't
> permit anything at all.  Maybe we need to rely on your '=foo' or 'x-foo'
> hack for letting QemuOpts still accept the old spelling during -drive
> but not during QMP.
>
>> 
>> qemu_rbd_array_opts()'s parameter @type now must be RBD_MON_HOST,
>> which is silly.  This will be cleaned up shortly.
>> 
>> Signed-off-by: Markus Armbruster <armbru@redhat.com>
>> ---
>>  block/rbd.c          | 31 +++----------------------------
>>  qapi/block-core.json | 24 ------------------------
>>  2 files changed, 3 insertions(+), 52 deletions(-)
>> 
>
>> +++ b/qapi/block-core.json
>> @@ -2601,27 +2601,6 @@
>>  
>>  
>>  ##
>> -# @RbdAuthSupport:
>> -#
>> -# An enumeration of RBD auth support
>> -#
>> -# Since: 2.9
>> -##
>> -{ 'enum': 'RbdAuthSupport',
>> -  'data': [ 'cephx', 'none' ] }
>> -
>> -
>> -##
>> -# @RbdAuthMethod:
>> -#
>> -# An enumeration of rados auth_supported types
>> -#
>> -# Since: 2.9
>> -##
>> -{ 'struct': 'RbdAuthMethod',
>> -  'data': { 'auth': 'RbdAuthSupport' } }
>> -
>
> Removing the .json QMP support is fine. But I'm reluctant to give R-b
> without knowing for sure that -drive usage won't regress.

auth-supported landed in master only on March 2nd.

What libvirt usage exactly do you think this could break?