On Sat, Apr 15, 2023 at 10:20 AM Cindy Lu <lulu@xxxxxxxxxx> wrote: > > While using the no-batch mode with vIOMMU enabled > Qemu will call a large memory to unmap. Much larger than the memory > mapped to the kernel. The iotlb is NULL in the kernel and will return fail. This patch looks good but I don't understand the above. I think it's better to explain why such large unmap will lead to this error: Is it a batched unmap or a [0, ULONG_MAX] map? How could we end up the NULL? > Which causes failure. > To fix this, we will not remove the AS while the iotlb->nmaps is 0. > This will free in the vhost_vdpa_clean > > Signed-off-by: Cindy Lu <lulu@xxxxxxxxxx> Do we need a fix tag and does it need to go for -stable? Thanks > --- > drivers/vhost/vdpa.c | 8 +------- > 1 file changed, 1 insertion(+), 7 deletions(-) > > diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c > index 7be9d9d8f01c..74c7d1f978b7 100644 > --- a/drivers/vhost/vdpa.c > +++ b/drivers/vhost/vdpa.c > @@ -851,11 +851,7 @@ static void vhost_vdpa_unmap(struct vhost_vdpa *v, > if (!v->in_batch) > ops->set_map(vdpa, asid, iotlb); > } > - /* If we are in the middle of batch processing, delay the free > - * of AS until BATCH_END. > - */ > - if (!v->in_batch && !iotlb->nmaps) > - vhost_vdpa_remove_as(v, asid); > + > } > > static int vhost_vdpa_va_map(struct vhost_vdpa *v, > @@ -1112,8 +1108,6 @@ static int vhost_vdpa_process_iotlb_msg(struct vhost_dev *dev, u32 asid, > if (v->in_batch && ops->set_map) > ops->set_map(vdpa, asid, iotlb); > v->in_batch = false; > - if (!iotlb->nmaps) > - vhost_vdpa_remove_as(v, asid); > break; > default: > r = -EINVAL; > -- > 2.34.3 > _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
