From 3f161d1572e7a4dee709507f71433c1a4d0b9c64 Mon Sep 17 00:00:00 2001 From: Chris Lew Date: Tue, 11 Oct 2022 13:15:10 -0700 Subject: [PATCH] net: qrtr: mhi: synchronize qrtr and mhi preparation A dl callback can be received anytime after mhi_prepare_for_transfer has been called. There is a window where the callback may happen before the probe initializes the qrtr_mhi_dev state. Move mhi_prepare_for_transfer after the registering the endpoint. Once moved, the reverse can happen where qrtr will try to send a packet before the channels are prepared. Add a wait in the sending path to ensure the channels are prepared before trying to do a ul transfer. Change-Id: Ib5bf34ec8c1fa56a8ce29c89449d062de7133846 Signed-off-by: Bhaumik Bhatt Signed-off-by: Chris Lew --- net/qrtr/mhi.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/net/qrtr/mhi.c b/net/qrtr/mhi.c index 9ced13c0627a..142e675eb496 100644 --- a/net/qrtr/mhi.c +++ b/net/qrtr/mhi.c @@ -1,6 +1,7 @@ // SPDX-License-Identifier: GPL-2.0 /* * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved. + * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved. */ #include @@ -15,6 +16,7 @@ struct qrtr_mhi_dev { struct qrtr_endpoint ep; struct mhi_device *mhi_dev; struct device *dev; + struct completion prepared; }; /* From MHI to QRTR */ @@ -53,6 +55,10 @@ static int qcom_mhi_qrtr_send(struct qrtr_endpoint *ep, struct sk_buff *skb) if (skb->sk) sock_hold(skb->sk); + rc = wait_for_completion_interruptible(&qdev->prepared); + if (rc) + goto free_skb; + rc = skb_linearize(skb); if (rc) goto free_skb; @@ -85,6 +91,7 @@ static int qcom_mhi_qrtr_probe(struct mhi_device *mhi_dev, qdev->mhi_dev = mhi_dev; qdev->dev = &mhi_dev->dev; qdev->ep.xmit = qcom_mhi_qrtr_send; + init_completion(&qdev->prepared); dev_set_drvdata(&mhi_dev->dev, qdev); rc = qrtr_endpoint_register(&qdev->ep, QRTR_EP_NID_AUTO); @@ -97,6 +104,7 @@ static int qcom_mhi_qrtr_probe(struct mhi_device *mhi_dev, qrtr_endpoint_unregister(&qdev->ep); return rc; } + complete_all(&qdev->prepared); dev_dbg(qdev->dev, "Qualcomm MHI QRTR driver probed\n");