From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Sender: List-Post: List-Help: List-Unsubscribe: List-Subscribe: From: Cornelia Huck In-Reply-To: <7d27538d-f185-c1fe-b19d-716930fd3f08@redhat.com> References: <20221123210706.21476-1-mst@redhat.com> <20221123210706.21476-10-mst@redhat.com> <20221124033204-mutt-send-email-mst@kernel.org> <7d27538d-f185-c1fe-b19d-716930fd3f08@redhat.com> Date: Fri, 25 Nov 2022 12:42:23 +0100 Message-ID: <87tu2ngt0g.fsf@redhat.com> MIME-Version: 1.0 Subject: [virtio] Re: [PATCH v9 09/10] admin: conformance clauses Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable To: Jason Wang , "Michael S. Tsirkin" Cc: virtio-comment@lists.oasis-open.org, virtio-dev@lists.oasis-open.org, sgarzare@redhat.com, stefanha@redhat.com, nrupal.jani@intel.com, Piotr.Uminski@intel.com, hang.yuan@intel.com, virtio@lists.oasis-open.org, Zhu Lingshan , pasic@linux.ibm.com, Shahaf Shuler , Parav Pandit , Max Gurtovoy List-ID: On Fri, Nov 25 2022, Jason Wang wrote: > =E5=9C=A8 2022/11/24 16:36, Michael S. Tsirkin =E5=86=99=E9=81=93: >> On Thu, Nov 24, 2022 at 02:51:21PM +0800, Jason Wang wrote: >>> On Thu, Nov 24, 2022 at 5:08 AM Michael S. Tsirkin wro= te: >>>> +The device MUST NOT fail a command solely because the buffers >>>> +provided are shorter or longer than described in this >>>> +specification. >>> I may miss something but how can it work if the buffer is shorter? >> driver does not care what's there. >> >> this is mostly for forward compatibility - we'll add more fields and >> I don't want to explain separately that old drivers post >> short buffers with less fields. > > > For example: > > The patch said: > > struct virtio_admin_cmd_list { > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 /* Indicates which of the below fie= lds were returned > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 le32 device_admin_cmds[]; > }; > > Does it mean the query can still succeed even if there's no space for=20 > virtio_admin_cmd_list in the writable buffer? Can we pick an absolute minimum length? All drivers need to be able to at least accommodate this one. Or is it ok for the driver to send a completely useless query that doesn't get any data back? --------------------------------------------------------------------- To unsubscribe from this mail list, you must leave the OASIS TC that=20 generates this mail. Follow this link to all your TCs in OASIS at: https://www.oasis-open.org/apps/org/workgroup/portal/my_workgroups.php=20