Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio fixes from Michael Tsirkin:
 "virtio,vhost: last minute fixes

  More small fixes. Most notably this fixes crashes and hangs in
  vhost-net"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  MAINTAINERS, mailmap: Update address for Peter Hilber
  virtio_config: clarify output parameters
  uapi: vduse: fix typo in comment
  vhost: Take a reference on the task in struct vhost_task.
  vhost-net: flush batched before enabling notifications
  Revert "vhost/net: Defer TX queue re-enable until after sendmsg"
  vhost-net: unbreak busy polling
  vhost-scsi: fix argument order in tport allocation error message

Author: torvalds

.mailmap

@@ -623,6 +623,7 @@ Paulo Alcantara <pc@manguebit.org> <palcantara@suse.com>
 Paulo Alcantara <pc@manguebit.org> <pc@manguebit.com>
 Pavankumar Kondeti <quic_pkondeti@quicinc.com> <pkondeti@codeaurora.org>
 Peter A Jonsson <pj@ludd.ltu.se>
+Peter Hilber <peter.hilber@oss.qualcomm.com> <quic_philber@quicinc.com>
 Peter Oruba <peter.oruba@amd.com>
 Peter Oruba <peter@oruba.de>
 Pierre-Louis Bossart <pierre-louis.bossart@linux.dev> <pierre-louis.bossart@linux.intel.com>

MAINTAINERS

@@ -26785,7 +26785,7 @@ F:	drivers/nvdimm/nd_virtio.c
 F:	drivers/nvdimm/virtio_pmem.c
 
 VIRTIO RTC DRIVER
-M:	Peter Hilber <quic_philber@quicinc.com>
+M:	Peter Hilber <peter.hilber@oss.qualcomm.com>
 L:	virtualization@lists.linux.dev
 S:	Maintained
 F:	drivers/virtio/virtio_rtc_*

drivers/vhost/net.c

@@ -765,11 +765,11 @@ static void handle_tx_copy(struct vhost_net *net, struct socket *sock)
 	int err;
 	int sent_pkts = 0;
 	bool sock_can_batch = (sock->sk->sk_sndbuf == INT_MAX);
-	bool busyloop_intr;
 	bool in_order = vhost_has_feature(vq, VIRTIO_F_IN_ORDER);
 
 	do {
-		busyloop_intr = false;
+		bool busyloop_intr = false;
+
 		if (nvq->done_idx == VHOST_NET_BATCH)
 			vhost_tx_batch(net, nvq, sock, &msg);
 
@@ -780,10 +780,18 @@ static void handle_tx_copy(struct vhost_net *net, struct socket *sock)
 			break;
 		/* Nothing new?  Wait for eventfd to tell us they refilled. */
 		if (head == vq->num) {
-			/* Kicks are disabled at this point, break loop and
-			 * process any remaining batched packets. Queue will
-			 * be re-enabled afterwards.
+			/* Flush batched packets to handle pending RX
+			 * work (if busyloop_intr is set) and to avoid
+			 * unnecessary virtqueue kicks.
 			 */
+			vhost_tx_batch(net, nvq, sock, &msg);
+			if (unlikely(busyloop_intr)) {
+				vhost_poll_queue(&vq->poll);
+			} else if (unlikely(vhost_enable_notify(&net->dev,
+								vq))) {
+				vhost_disable_notify(&net->dev, vq);
+				continue;
+			}
 			break;
 		}
 
@@ -839,22 +847,7 @@ static void handle_tx_copy(struct vhost_net *net, struct socket *sock)
 		++nvq->done_idx;
 	} while (likely(!vhost_exceeds_weight(vq, ++sent_pkts, total_len)));
 
-	/* Kicks are still disabled, dispatch any remaining batched msgs. */
 	vhost_tx_batch(net, nvq, sock, &msg);
-
-	if (unlikely(busyloop_intr))
-		/* If interrupted while doing busy polling, requeue the
-		 * handler to be fair handle_rx as well as other tasks
-		 * waiting on cpu.
-		 */
-		vhost_poll_queue(&vq->poll);
-	else
-		/* All of our work has been completed; however, before
-		 * leaving the TX handler, do one last check for work,
-		 * and requeue handler if necessary. If there is no work,
-		 * queue will be reenabled.
-		 */
-		vhost_net_busy_poll_try_queue(net, vq);
 }
 
 static void handle_tx_zerocopy(struct vhost_net *net, struct socket *sock)
@@ -1014,7 +1007,7 @@ static int peek_head_len(struct vhost_net_virtqueue *rvq, struct sock *sk)
 }
 
 static int vhost_net_rx_peek_head_len(struct vhost_net *net, struct sock *sk,
-				      bool *busyloop_intr, unsigned int count)
+				      bool *busyloop_intr, unsigned int *count)
 {
 	struct vhost_net_virtqueue *rnvq = &net->vqs[VHOST_NET_VQ_RX];
 	struct vhost_net_virtqueue *tnvq = &net->vqs[VHOST_NET_VQ_TX];
@@ -1024,7 +1017,8 @@ static int vhost_net_rx_peek_head_len(struct vhost_net *net, struct sock *sk,
 
 	if (!len && rvq->busyloop_timeout) {
 		/* Flush batched heads first */
-		vhost_net_signal_used(rnvq, count);
+		vhost_net_signal_used(rnvq, *count);
+		*count = 0;
 		/* Both tx vq and rx socket were polled here */
 		vhost_net_busy_poll(net, rvq, tvq, busyloop_intr, true);
 
@@ -1180,7 +1174,7 @@ static void handle_rx(struct vhost_net *net)
 
 	do {
 		sock_len = vhost_net_rx_peek_head_len(net, sock->sk,
-						      &busyloop_intr, count);
+						      &busyloop_intr, &count);
 		if (!sock_len)
 			break;
 		sock_len += sock_hlen;

drivers/vhost/scsi.c

@@ -2884,7 +2884,7 @@ vhost_scsi_make_tport(struct target_fabric_configfs *tf,
 check_len:
 	if (strlen(name) >= VHOST_SCSI_NAMELEN) {
 		pr_err("Emulated %s Address: %s, exceeds"
-			" max: %d\n", name, vhost_scsi_dump_proto_id(tport),
+			" max: %d\n", vhost_scsi_dump_proto_id(tport), name,
 			VHOST_SCSI_NAMELEN);
 		kfree(tport);
 		return ERR_PTR(-EINVAL);

include/linux/virtio_config.h

@@ -193,14 +193,15 @@ static inline bool virtio_has_feature(const struct virtio_device *vdev,
 }
 
 static inline void virtio_get_features(struct virtio_device *vdev,
-				       u64 *features)
+				       u64 *features_out)
 {
 	if (vdev->config->get_extended_features) {
-		vdev->config->get_extended_features(vdev, features);
+		vdev->config->get_extended_features(vdev, features_out);
 		return;
 	}
 
-	virtio_features_from_u64(features, vdev->config->get_features(vdev));
+	virtio_features_from_u64(features_out,
+		vdev->config->get_features(vdev));
 }
 
 /**
@@ -326,11 +327,11 @@ int virtqueue_set_affinity(struct virtqueue *vq, const struct cpumask *cpu_mask)
 
 static inline
 bool virtio_get_shm_region(struct virtio_device *vdev,
-			   struct virtio_shm_region *region, u8 id)
+			   struct virtio_shm_region *region_out, u8 id)
 {
 	if (!vdev->config->get_shm_region)
 		return false;
-	return vdev->config->get_shm_region(vdev, region, id);
+	return vdev->config->get_shm_region(vdev, region_out, id);
 }
 
 static inline bool virtio_is_little_endian(struct virtio_device *vdev)

include/uapi/linux/vduse.h

@@ -237,7 +237,7 @@ struct vduse_iova_umem {
  * struct vduse_iova_info - information of one IOVA region
  * @start: start of the IOVA region
  * @last: last of the IOVA region
- * @capability: capability of the IOVA regsion
+ * @capability: capability of the IOVA region
  * @reserved: for future use, needs to be initialized to zero
  *
  * Structure used by VDUSE_IOTLB_GET_INFO ioctl to get information of

kernel/vhost_task.c

@@ -100,6 +100,7 @@ void vhost_task_stop(struct vhost_task *vtsk)
 	 * freeing it below.
 	 */
 	wait_for_completion(&vtsk->exited);
+	put_task_struct(vtsk->task);
 	kfree(vtsk);
 }
 EXPORT_SYMBOL_GPL(vhost_task_stop);
@@ -148,7 +149,7 @@ struct vhost_task *vhost_task_create(bool (*fn)(void *),
 		return ERR_CAST(tsk);
 	}
 
-	vtsk->task = tsk;
+	vtsk->task = get_task_struct(tsk);
 	return vtsk;
 }
 EXPORT_SYMBOL_GPL(vhost_task_create);