From patchwork Mon Oct 5 15:26:24 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 290667 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C5C7AC4363A for ; Mon, 5 Oct 2020 15:28:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8AE6D20637 for ; Mon, 5 Oct 2020 15:28:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601911724; bh=5gIp2ADyAyFMb59jSVGzJtWs1+8nMdYs+8Bal17LoZA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=QubK3byC4B61F9FQAXW9r4DeNJYb821SMxGA3ozSxGA44ZClXnXXFpFwY6WIz97Xm fR0569FrLGcSf8XZwQxjFuxyycmPL/zUF280ElaygCgBAYXYEaShojzN0eKczRUy95 qCx9ZBLpkfTgy9KfuxJqL7QBlDRfd7dOBsFrt/aw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726680AbgJEP2n (ORCPT ); Mon, 5 Oct 2020 11:28:43 -0400 Received: from mail.kernel.org ([198.145.29.99]:53416 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726659AbgJEP2a (ORCPT ); Mon, 5 Oct 2020 11:28:30 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B3E832085B; Mon, 5 Oct 2020 15:28:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601911709; bh=5gIp2ADyAyFMb59jSVGzJtWs1+8nMdYs+8Bal17LoZA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DKvZ6/VNWfBtCG7jFtGYjfNTxOguRhU5l4+5MNqUBa1gLdOZQxb/F8YXc3wpM+Fgh XuL25m87Ar1nPCwjW+DytmqpGJjgiZMn/oCv49amHbRakyjXQWCj56EReBrRGK20sl 2oePCwDFfA92AD7eJ0JQlUfaMGWYFTwILwusBQP8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Stefan Hajnoczi , "Michael S. Tsirkin" , Stefano Garzarella , "David S. Miller" , Sasha Levin Subject: [PATCH 4.19 07/38] vsock/virtio: stop workers during the .remove() Date: Mon, 5 Oct 2020 17:26:24 +0200 Message-Id: <20201005142109.015282314@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201005142108.650363140@linuxfoundation.org> References: <20201005142108.650363140@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Stefano Garzarella [ Upstream commit 17dd1367389cfe7f150790c83247b68e0c19d106 ] Before to call vdev->config->reset(vdev) we need to be sure that no one is accessing the device, for this reason, we add new variables in the struct virtio_vsock to stop the workers during the .remove(). This patch also add few comments before vdev->config->reset(vdev) and vdev->config->del_vqs(vdev). Suggested-by: Stefan Hajnoczi Suggested-by: Michael S. Tsirkin Signed-off-by: Stefano Garzarella Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/vmw_vsock/virtio_transport.c | 51 +++++++++++++++++++++++++++++++- 1 file changed, 50 insertions(+), 1 deletion(-) diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c index 68186419c445f..4bc217ef56945 100644 --- a/net/vmw_vsock/virtio_transport.c +++ b/net/vmw_vsock/virtio_transport.c @@ -39,6 +39,7 @@ struct virtio_vsock { * must be accessed with tx_lock held. */ struct mutex tx_lock; + bool tx_run; struct work_struct send_pkt_work; spinlock_t send_pkt_list_lock; @@ -54,6 +55,7 @@ struct virtio_vsock { * must be accessed with rx_lock held. */ struct mutex rx_lock; + bool rx_run; int rx_buf_nr; int rx_buf_max_nr; @@ -61,6 +63,7 @@ struct virtio_vsock { * vqs[VSOCK_VQ_EVENT] must be accessed with event_lock held. */ struct mutex event_lock; + bool event_run; struct virtio_vsock_event event_list[8]; u32 guest_cid; @@ -95,6 +98,10 @@ static void virtio_transport_loopback_work(struct work_struct *work) spin_unlock_bh(&vsock->loopback_list_lock); mutex_lock(&vsock->rx_lock); + + if (!vsock->rx_run) + goto out; + while (!list_empty(&pkts)) { struct virtio_vsock_pkt *pkt; @@ -103,6 +110,7 @@ static void virtio_transport_loopback_work(struct work_struct *work) virtio_transport_recv_pkt(pkt); } +out: mutex_unlock(&vsock->rx_lock); } @@ -131,6 +139,9 @@ virtio_transport_send_pkt_work(struct work_struct *work) mutex_lock(&vsock->tx_lock); + if (!vsock->tx_run) + goto out; + vq = vsock->vqs[VSOCK_VQ_TX]; for (;;) { @@ -189,6 +200,7 @@ virtio_transport_send_pkt_work(struct work_struct *work) if (added) virtqueue_kick(vq); +out: mutex_unlock(&vsock->tx_lock); if (restart_rx) @@ -324,6 +336,10 @@ static void virtio_transport_tx_work(struct work_struct *work) vq = vsock->vqs[VSOCK_VQ_TX]; mutex_lock(&vsock->tx_lock); + + if (!vsock->tx_run) + goto out; + do { struct virtio_vsock_pkt *pkt; unsigned int len; @@ -334,6 +350,8 @@ static void virtio_transport_tx_work(struct work_struct *work) added = true; } } while (!virtqueue_enable_cb(vq)); + +out: mutex_unlock(&vsock->tx_lock); if (added) @@ -362,6 +380,9 @@ static void virtio_transport_rx_work(struct work_struct *work) mutex_lock(&vsock->rx_lock); + if (!vsock->rx_run) + goto out; + do { virtqueue_disable_cb(vq); for (;;) { @@ -471,6 +492,9 @@ static void virtio_transport_event_work(struct work_struct *work) mutex_lock(&vsock->event_lock); + if (!vsock->event_run) + goto out; + do { struct virtio_vsock_event *event; unsigned int len; @@ -485,7 +509,7 @@ static void virtio_transport_event_work(struct work_struct *work) } while (!virtqueue_enable_cb(vq)); virtqueue_kick(vsock->vqs[VSOCK_VQ_EVENT]); - +out: mutex_unlock(&vsock->event_lock); } @@ -621,12 +645,18 @@ static int virtio_vsock_probe(struct virtio_device *vdev) INIT_WORK(&vsock->send_pkt_work, virtio_transport_send_pkt_work); INIT_WORK(&vsock->loopback_work, virtio_transport_loopback_work); + mutex_lock(&vsock->tx_lock); + vsock->tx_run = true; + mutex_unlock(&vsock->tx_lock); + mutex_lock(&vsock->rx_lock); virtio_vsock_rx_fill(vsock); + vsock->rx_run = true; mutex_unlock(&vsock->rx_lock); mutex_lock(&vsock->event_lock); virtio_vsock_event_fill(vsock); + vsock->event_run = true; mutex_unlock(&vsock->event_lock); vdev->priv = vsock; @@ -661,6 +691,24 @@ static void virtio_vsock_remove(struct virtio_device *vdev) /* Reset all connected sockets when the device disappear */ vsock_for_each_connected_socket(virtio_vsock_reset_sock); + /* Stop all work handlers to make sure no one is accessing the device, + * so we can safely call vdev->config->reset(). + */ + mutex_lock(&vsock->rx_lock); + vsock->rx_run = false; + mutex_unlock(&vsock->rx_lock); + + mutex_lock(&vsock->tx_lock); + vsock->tx_run = false; + mutex_unlock(&vsock->tx_lock); + + mutex_lock(&vsock->event_lock); + vsock->event_run = false; + mutex_unlock(&vsock->event_lock); + + /* Flush all device writes and interrupts, device will not use any + * more buffers. + */ vdev->config->reset(vdev); mutex_lock(&vsock->rx_lock); @@ -691,6 +739,7 @@ static void virtio_vsock_remove(struct virtio_device *vdev) } spin_unlock_bh(&vsock->loopback_list_lock); + /* Delete virtqueues and flush outstanding callbacks if any */ vdev->config->del_vqs(vdev); mutex_unlock(&the_virtio_vsock_mutex);