summaryrefslogtreecommitdiff
path: root/net
diff options
context:
space:
mode:
authorMaxim Kochetkov <fido_max@inbox.ru>2022-08-11 12:48:40 +0300
committerDavid S. Miller <davem@davemloft.net>2022-08-15 11:21:42 +0100
commit68a838b84effb7b57ba7d50b1863fc6ae35a54ce (patch)
tree0a81105de24c9d2e3fbd246a4e3e3657848e14e1 /net
parent777885673122b78b2abd2f1e428730961a786ff2 (diff)
net: qrtr: start MHI channel after endpoit creation
MHI channel may generates event/interrupt right after enabling. It may leads to 2 race conditions issues. 1) Such event may be dropped by qcom_mhi_qrtr_dl_callback() at check: if (!qdev || mhi_res->transaction_status) return; Because dev_set_drvdata(&mhi_dev->dev, qdev) may be not performed at this moment. In this situation qrtr-ns will be unable to enumerate services in device. --------------------------------------------------------------- 2) Such event may come at the moment after dev_set_drvdata() and before qrtr_endpoint_register(). In this case kernel will panic with accessing wrong pointer at qcom_mhi_qrtr_dl_callback(): rc = qrtr_endpoint_post(&qdev->ep, mhi_res->buf_addr, mhi_res->bytes_xferd); Because endpoint is not created yet. -------------------------------------------------------------- So move mhi_prepare_for_transfer_autoqueue after endpoint creation to fix it. Fixes: a2e2cc0dbb11 ("net: qrtr: Start MHI channels during init") Signed-off-by: Maxim Kochetkov <fido_max@inbox.ru> Reviewed-by: Hemant Kumar <quic_hemantk@quicinc.com> Reviewed-by: Manivannan Sadhasivam <mani@kernel.org> Reviewed-by: Loic Poulain <loic.poulain@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
-rw-r--r--net/qrtr/mhi.c12
1 files changed, 7 insertions, 5 deletions
diff --git a/net/qrtr/mhi.c b/net/qrtr/mhi.c
index 18196e1c8c2f..9ced13c0627a 100644
--- a/net/qrtr/mhi.c
+++ b/net/qrtr/mhi.c
@@ -78,11 +78,6 @@ static int qcom_mhi_qrtr_probe(struct mhi_device *mhi_dev,
struct qrtr_mhi_dev *qdev;
int rc;
- /* start channels */
- rc = mhi_prepare_for_transfer_autoqueue(mhi_dev);
- if (rc)
- return rc;
-
qdev = devm_kzalloc(&mhi_dev->dev, sizeof(*qdev), GFP_KERNEL);
if (!qdev)
return -ENOMEM;
@@ -96,6 +91,13 @@ static int qcom_mhi_qrtr_probe(struct mhi_device *mhi_dev,
if (rc)
return rc;
+ /* start channels */
+ rc = mhi_prepare_for_transfer_autoqueue(mhi_dev);
+ if (rc) {
+ qrtr_endpoint_unregister(&qdev->ep);
+ return rc;
+ }
+
dev_dbg(qdev->dev, "Qualcomm MHI QRTR driver probed\n");
return 0;