On Thu, May 14, 2020 at 03:25:49PM +0800, Jason Wang wrote: > We reset IOTLB during device reset this breaks the assumption that the > mapping needs to be controlled via vDPA DMA ops explicitly in a > incremental way. So the networking will be broken after e.g a guest > reset. > > Fix this by not resetting the IOTLB during device reset. > > Signed-off-by: Jason Wang <[email protected]>
That's a bit weird, and can be a security risk if state leaks between security domains through this. And there's 0 chance any hardware implementation can keep the translations around across resets - there is simply nowhere to keep them. IMHO we need a different way to make this work, simulator needs to look like a hardware device as much as possible. > --- > drivers/vdpa/vdpa_sim/vdpa_sim.c | 2 -- > 1 file changed, 2 deletions(-) > > diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c > b/drivers/vdpa/vdpa_sim/vdpa_sim.c > index 7957d2d41fc4..cc5525743a25 100644 > --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c > +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c > @@ -119,8 +119,6 @@ static void vdpasim_reset(struct vdpasim *vdpasim) > for (i = 0; i < VDPASIM_VQ_NUM; i++) > vdpasim_vq_reset(&vdpasim->vqs[i]); > > - vhost_iotlb_reset(vdpasim->iommu); > - > vdpasim->features = 0; > vdpasim->status = 0; > ++vdpasim->generation; > -- > 2.20.1
