From ea095a7abde31e30925b561e468493bbd8b49759 Mon Sep 17 00:00:00 2001
From: Maxime Coquelin <maxime.coquelin@redhat.com>
Date: Tue, 9 Jan 2024 12:10:24 +0100
Subject: [PATCH] vduse: Temporarily fail if control queue feature requested
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BugLink: https://bugs.launchpad.net/bugs/2076435

[ Upstream commit 56e71885b0349241c07631a7b979b61e81afab6a ]

Virtio-net driver control queue implementation is not safe
when used with VDUSE. If the VDUSE application does not
reply to control queue messages, it currently ends up
hanging the kernel thread sending this command.

Some work is on-going to make the control queue
implementation robust with VDUSE. Until it is completed,
let's fail features check if control-queue feature is
requested.

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Message-Id: <20240109111025.1320976-3-maxime.coquelin@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Portia Stephens <portia.stephens@canonical.com>
Signed-off-by: Roxana Nicolescu <roxana.nicolescu@canonical.com>
---
 drivers/vdpa/vdpa_user/vduse_dev.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c
index 477f4ba797e9..eac7ed8ab308 100644
--- a/drivers/vdpa/vdpa_user/vduse_dev.c
+++ b/drivers/vdpa/vdpa_user/vduse_dev.c
@@ -8,6 +8,7 @@
  *
  */
 
+#include "linux/virtio_net.h"
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/cdev.h>
@@ -28,6 +29,7 @@
 #include <uapi/linux/virtio_config.h>
 #include <uapi/linux/virtio_ids.h>
 #include <uapi/linux/virtio_blk.h>
+#include <uapi/linux/virtio_ring.h>
 #include <linux/mod_devicetable.h>
 
 #include "iova_domain.h"
@@ -1680,6 +1682,9 @@ static bool features_is_valid(struct vduse_dev_config *config)
 	if ((config->device_id == VIRTIO_ID_BLOCK) &&
 			(config->features & BIT_ULL(VIRTIO_BLK_F_CONFIG_WCE)))
 		return false;
+	else if ((config->device_id == VIRTIO_ID_NET) &&
+			(config->features & BIT_ULL(VIRTIO_NET_F_CTRL_VQ)))
+		return false;
 
 	return true;
 }