QE did a sanity test on v4 of this series using the vdpa_sim device,everything is working fine.
Tested-by: Lei Yang <leiy...@redhat.com> On Fri, May 26, 2023 at 11:31 PM Eugenio Pérez <epere...@redhat.com> wrote: > > QEMU v8.0 is able to switch dynamically between vhost-vdpa passthrough > and SVQ mode as long as the net device does not have CVQ. The net device > state followed (and migrated) by CVQ requires special care. > > A pre-requisite to add CVQ to that framework is to determine if devices with > CVQ are migratable or not at initialization time. The solution to it is to > always shadow only CVQ, and vq groups and ASID are used for that. > > However, current qemu version only checks ASID at device start (as "driver set > DRIVER_OK status bit"), not at device initialization. A check at > initialization time is required. Otherwise, the guest would be able to set > and remove migration blockers at will [1]. > > This series is a requisite for migration of vhost-vdpa net devices with CVQ. > However it already makes sense by its own, as it reduces the number of ioctls > at migration time, decreasing the error paths there. > > [1] > https://lore.kernel.org/qemu-devel/2616f0cd-f9e8-d183-ea78-db1be4825...@redhat.com/ > --- > v4: > * Only probe one of MQ or !MQ. > * Merge vhost_vdpa_cvq_is_isolated in vhost_vdpa_probe_cvq_isolation > * Call ioctl directly instead of adding functions. > > v3: > * Only record cvq_isolated, true if the device have cvq isolated in both !MQ > * and MQ configurations. > * Drop the cache of cvq group, it can be done on top > > v2: > * Take out the reset of the device from vhost_vdpa_cvq_is_isolated > (reported by Lei Yang). > * Expand patch messages by Stefano G. questions. > > Eugenio Pérez (2): > vdpa: return errno in vhost_vdpa_get_vring_group error > vdpa: move CVQ isolation check to net_init_vhost_vdpa > > net/vhost-vdpa.c | 147 ++++++++++++++++++++++++++++++++++++----------- > 1 file changed, 112 insertions(+), 35 deletions(-) > > -- > 2.31.1 > >
