Commit c2a53da7 authored by Darek Stojaczyk's avatar Darek Stojaczyk Committed by Changpeng Liu
Browse files

vhost: don't check indirect desc feature flag 



Windows Virtio drivers use indirect descriptors without
negotiating their feature flag, which is explicitly
forbidden by the Virtio 1.0 spec. "(2.4.5.3.1 Driver
Requirements: Indirect Descriptors) The driver MUST NOT
set the VIRTQ_DESC_F_INDIRECT flag unless the
VIRTIO_F_INDIRECT_DESC feature was negotiated.".

Violating this rule doesn't cause any issues for SPDK
vhost, but triggers an assert, so we can only run Windows
VMs with non-debug SPDK builds.

This patch removes the assert and allows Windows VMs
to be run with debug versions of SPDK vhost.

Fixes #650

Change-Id: I95f534c33c384a4e1126a8c343c21eb63ec7bcef
Signed-off-by: default avatarDarek Stojaczyk <dariusz.stojaczyk@intel.com>
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/447803


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
Reviewed-by: default avatarChangpeng Liu <changpeng.liu@intel.com>
parent 5a77afa8

lib/vhost/vhost.c

+0 −1
Original line number Diff line number Diff line
@@ -233,7 +233,6 @@ spdk_vhost_vq_get_desc(struct spdk_vhost_session *vsession, struct spdk_vhost_vi 
	*desc = &virtqueue->vring.desc[req_idx];



	if (spdk_vhost_vring_desc_is_indirect(*desc)) {

		assert(spdk_vhost_dev_has_feature(vsession, VIRTIO_RING_F_INDIRECT_DESC));

		*desc_table_size = (*desc)->len / sizeof(**desc);

		*desc_table = spdk_vhost_gpa_to_vva(vsession, (*desc)->addr,

						    sizeof(**desc) * *desc_table_size);