When debugging a new vhost user you may be surprised to see VHOST_USER_F_PROTOCOL getting squashed in the maze of backend_features, acked_features and guest_features. Expand the description here to help the next poor soul trying to work through this.
Signed-off-by: Alex Bennée <alex.ben...@linaro.org> --- include/hw/virtio/virtio.h | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h index db1c0ddf6b..2b2587d324 100644 --- a/include/hw/virtio/virtio.h +++ b/include/hw/virtio/virtio.h @@ -24,7 +24,12 @@ #include "qom/object.h" #include "hw/virtio/vhost.h" -/* A guest should never accept this. It implies negotiation is broken. */ +/* + * A guest should never accept this. It implies negotiation is + * broken between the driver frontend and the device. This bit is + * re-used for vhost to advertise VHOST_USER_F_PROTOCOL_FEATURES + * between QEMU and a vhost backend. + */ #define VIRTIO_F_BAD_FEATURE 30 #define VIRTIO_LEGACY_FEATURES ((0x1ULL << VIRTIO_F_BAD_FEATURE) | \ -- 2.30.2
