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author | Jack Pham <quic_jackp@quicinc.com> | 2023-01-09 23:12:18 -0800 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-01-17 17:06:18 +0100 |
commit | fac4b8633fd682ecc8e9cff61cb3e33374a1c7e5 (patch) | |
tree | 852bd83204f169eb29c327238c56410bed201b02 /drivers | |
parent | bd449ad8cee9d4b523abbdfa73e1a2a08333f331 (diff) | |
download | linux-stable-fac4b8633fd682ecc8e9cff61cb3e33374a1c7e5.tar.gz linux-stable-fac4b8633fd682ecc8e9cff61cb3e33374a1c7e5.tar.bz2 linux-stable-fac4b8633fd682ecc8e9cff61cb3e33374a1c7e5.zip |
usb: ucsi: Ensure connector delayed work items are flushed
During ucsi_unregister() when destroying a connector's workqueue, there
may still be pending delayed work items that haven't been scheduled yet.
Because queue_delayed_work() uses a separate timer to schedule a work
item, the destroy_workqueue() call is not aware of any pending items.
Hence when a pending item's timer expires it would then try to queue on
a dangling workqueue pointer.
Fix this by keeping track of all work items in a list, so that prior to
destroying the workqueue any pending items can be flushed. Do this by
calling mod_delayed_work() as that will cause pending items to get
queued immediately, which then allows the ensuing destroy_workqueue() to
implicitly drain all currently queued items to completion and free
themselves.
Fixes: b9aa02ca39a4 ("usb: typec: ucsi: Add polling mechanism for partner tasks like alt mode checking")
Suggested-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Co-developed-by: Linyu Yuan <quic_linyyuan@quicinc.com>
Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
Signed-off-by: Jack Pham <quic_jackp@quicinc.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20230110071218.26261-1-quic_jackp@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/usb/typec/ucsi/ucsi.c | 24 | ||||
-rw-r--r-- | drivers/usb/typec/ucsi/ucsi.h | 1 |
2 files changed, 22 insertions, 3 deletions
diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c index eabe519013e7..1292241d581a 100644 --- a/drivers/usb/typec/ucsi/ucsi.c +++ b/drivers/usb/typec/ucsi/ucsi.c @@ -187,6 +187,7 @@ EXPORT_SYMBOL_GPL(ucsi_send_command); struct ucsi_work { struct delayed_work work; + struct list_head node; unsigned long delay; unsigned int count; struct ucsi_connector *con; @@ -202,6 +203,7 @@ static void ucsi_poll_worker(struct work_struct *work) mutex_lock(&con->lock); if (!con->partner) { + list_del(&uwork->node); mutex_unlock(&con->lock); kfree(uwork); return; @@ -209,10 +211,12 @@ static void ucsi_poll_worker(struct work_struct *work) ret = uwork->cb(con); - if (uwork->count-- && (ret == -EBUSY || ret == -ETIMEDOUT)) + if (uwork->count-- && (ret == -EBUSY || ret == -ETIMEDOUT)) { queue_delayed_work(con->wq, &uwork->work, uwork->delay); - else + } else { + list_del(&uwork->node); kfree(uwork); + } mutex_unlock(&con->lock); } @@ -236,6 +240,7 @@ static int ucsi_partner_task(struct ucsi_connector *con, uwork->con = con; uwork->cb = cb; + list_add_tail(&uwork->node, &con->partner_tasks); queue_delayed_work(con->wq, &uwork->work, delay); return 0; @@ -1056,6 +1061,7 @@ static int ucsi_register_port(struct ucsi *ucsi, int index) INIT_WORK(&con->work, ucsi_handle_connector_change); init_completion(&con->complete); mutex_init(&con->lock); + INIT_LIST_HEAD(&con->partner_tasks); con->num = index + 1; con->ucsi = ucsi; @@ -1420,8 +1426,20 @@ void ucsi_unregister(struct ucsi *ucsi) ucsi_unregister_altmodes(&ucsi->connector[i], UCSI_RECIPIENT_CON); ucsi_unregister_port_psy(&ucsi->connector[i]); - if (ucsi->connector[i].wq) + + if (ucsi->connector[i].wq) { + struct ucsi_work *uwork; + + mutex_lock(&ucsi->connector[i].lock); + /* + * queue delayed items immediately so they can execute + * and free themselves before the wq is destroyed + */ + list_for_each_entry(uwork, &ucsi->connector[i].partner_tasks, node) + mod_delayed_work(ucsi->connector[i].wq, &uwork->work, 0); + mutex_unlock(&ucsi->connector[i].lock); destroy_workqueue(ucsi->connector[i].wq); + } typec_unregister_port(ucsi->connector[i].port); } diff --git a/drivers/usb/typec/ucsi/ucsi.h b/drivers/usb/typec/ucsi/ucsi.h index c968474ee547..60ce9fb6e745 100644 --- a/drivers/usb/typec/ucsi/ucsi.h +++ b/drivers/usb/typec/ucsi/ucsi.h @@ -322,6 +322,7 @@ struct ucsi_connector { struct work_struct work; struct completion complete; struct workqueue_struct *wq; + struct list_head partner_tasks; struct typec_port *port; struct typec_partner *partner; |