Commit 45c0a209 authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

Merge branch 'virtio_net-fix-lock-warning-and-unrecoverable-state' 

Heng Qi says:

====================
virtio_net: fix lock warning and unrecoverable state

Patch 1 describes and fixes an issue where dim cannot return to
normal state in certain scenarios.

Patch 2 attempts to resolve lockdep's complaints that holding many
nested locks.
====================

Link: https://lore.kernel.org/r/20240528134116.117426-1-hengqi@linux.alibaba.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parents 89e281eb d1f0bd01

drivers/net/virtio_net.c

+17 −21
Original line number Diff line number Diff line
@@ -4259,7 +4259,6 @@ static int virtnet_send_rx_notf_coal_cmds(struct virtnet_info *vi, 
	struct virtio_net_ctrl_coal_rx *coal_rx __free(kfree) = NULL;

	bool rx_ctrl_dim_on = !!ec->use_adaptive_rx_coalesce;

	struct scatterlist sgs_rx;

	int ret = 0;

	int i;



	if (rx_ctrl_dim_on && !virtio_has_feature(vi->vdev, VIRTIO_NET_F_VQ_NOTF_COAL))
@@ -4269,27 +4268,27 @@ static int virtnet_send_rx_notf_coal_cmds(struct virtnet_info *vi, 
			       ec->rx_max_coalesced_frames != vi->intr_coal_rx.max_packets))

		return -EINVAL;



	/* Acquire all queues dim_locks */

	for (i = 0; i < vi->max_queue_pairs; i++)

		mutex_lock(&vi->rq[i].dim_lock);



	if (rx_ctrl_dim_on && !vi->rx_dim_enabled) {

		vi->rx_dim_enabled = true;

		for (i = 0; i < vi->max_queue_pairs; i++)

		for (i = 0; i < vi->max_queue_pairs; i++) {

			mutex_lock(&vi->rq[i].dim_lock);

			vi->rq[i].dim_enabled = true;

		goto unlock;

			mutex_unlock(&vi->rq[i].dim_lock);

		}

		return 0;

	}



	coal_rx = kzalloc(sizeof(*coal_rx), GFP_KERNEL);

	if (!coal_rx) {

		ret = -ENOMEM;

		goto unlock;

	}

	if (!coal_rx)

		return -ENOMEM;



	if (!rx_ctrl_dim_on && vi->rx_dim_enabled) {

		vi->rx_dim_enabled = false;

		for (i = 0; i < vi->max_queue_pairs; i++)

		for (i = 0; i < vi->max_queue_pairs; i++) {

			mutex_lock(&vi->rq[i].dim_lock);

			vi->rq[i].dim_enabled = false;

			mutex_unlock(&vi->rq[i].dim_lock);

		}

	}



	/* Since the per-queue coalescing params can be set,
@@ -4302,22 +4301,19 @@ static int virtnet_send_rx_notf_coal_cmds(struct virtnet_info *vi, 


	if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_NOTF_COAL,

				  VIRTIO_NET_CTRL_NOTF_COAL_RX_SET,

				  &sgs_rx)) {

		ret = -EINVAL;

		goto unlock;

	}

				  &sgs_rx))

		return -EINVAL;



	vi->intr_coal_rx.max_usecs = ec->rx_coalesce_usecs;

	vi->intr_coal_rx.max_packets = ec->rx_max_coalesced_frames;

	for (i = 0; i < vi->max_queue_pairs; i++) {

		mutex_lock(&vi->rq[i].dim_lock);

		vi->rq[i].intr_coal.max_usecs = ec->rx_coalesce_usecs;

		vi->rq[i].intr_coal.max_packets = ec->rx_max_coalesced_frames;

	}

unlock:

	for (i = vi->max_queue_pairs - 1; i >= 0; i--)

		mutex_unlock(&vi->rq[i].dim_lock);

	}



	return ret;

	return 0;

}



static int virtnet_send_notf_coal_cmds(struct virtnet_info *vi,
@@ -4419,9 +4415,9 @@ static void virtnet_rx_dim_work(struct work_struct *work) 
		if (err)

			pr_debug("%s: Failed to send dim parameters on rxq%d\n",

				 dev->name, qnum);

		dim->state = DIM_START_MEASURE;

	}

out:

	dim->state = DIM_START_MEASURE;

	mutex_unlock(&rq->dim_lock);

}