From: Sergey Senozhatsky Date: Fri, 15 May 2026 06:00:30 +0000 (+0900) Subject: usb: typec: ucsi: split connector lock classes X-Git-Url: http://git.ipfire.org/gitweb/?a=commitdiff_plain;h=8c22256bbafad3dc5fdbe9f684d045b67ff06a68;p=thirdparty%2Flinux.git usb: typec: ucsi: split connector lock classes Lockdep detects a possible recursive locking scenario during ucsi init: [ 5.418616] ============================================ [ 5.418634] WARNING: possible recursive locking detected [ 5.418706] -------------------------------------------- [ 5.418725] kworker/4:1/82 is trying to acquire lock: [ 5.418759] ffff888119a34648 (&con->lock){+.+.}-{3:3}, at: ucsi_init_work+0x1a78/0x2eb0 [typec_ucsi] [ 5.418801] but task is already holding lock: [ 5.418835] ffff888119a34080 (&con->lock){+.+.}-{3:3}, at: ucsi_init_work+0x1a78/0x2eb0 [typec_ucsi] [ 5.418884] other info that might help us debug this: [ 5.418904] Possible unsafe locking scenario: [ 5.418937] CPU0 [ 5.418956] ---- [ 5.418991] lock(&con->lock); [ 5.419013] lock(&con->lock); [ 5.419033] *** DEADLOCK *** [ 5.419387] Call Trace: [ 5.419406] [ 5.419425] dump_stack_lvl+0x61/0xa0 [ 5.419448] print_deadlock_bug+0x4a6/0x650 [ 5.419483] __lock_acquire+0x62b6/0x7f50 [ 5.419507] lock_acquire+0x11b/0x390 [ 5.419654] __mutex_lock+0xbc/0xcd0 [ 5.419741] ucsi_init_work+0x1a78/0x2eb0 [ 5.419785] ? worker_thread+0xf53/0x2bc0 [ 5.419819] worker_thread+0xff4/0x2bc0 [ 5.419842] kthread+0x2a7/0x330 [ 5.419863] ? __pfx_worker_thread+0x10/0x10 [ 5.419896] ? __pfx_kthread+0x10/0x10 [ 5.419916] ret_from_fork+0x38/0x70 [ 5.419936] ? __pfx_kthread+0x10/0x10 [ 5.419969] ret_from_fork_asm+0x1b/0x30 [ 5.419991] [ 5.420009] ---[ end trace 0000000000000000 ]--- The problem is that all connector locks belong to the same lockdep lock class, so the following loop: for (i = 0; i < ucsi->cap.num_connectors; i++) ucsi_register_port(connector[i]) mutex_lock(&connector[i]->lock) looks like a recursive acquire of the same mutex. Put each connector lock into a dedicated lock class so that lockdep doesn't see it as a possible recursion. Signed-off-by: Sergey Senozhatsky Reviewed-by: Heikki Krogerus Link: https://patch.msgid.link/20260515060042.136083-1-senozhatsky@chromium.org Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c index 5b7ad9e99cb9..43da7512dea0 100644 --- a/drivers/usb/typec/ucsi/ucsi.c +++ b/drivers/usb/typec/ucsi/ucsi.c @@ -1642,6 +1642,7 @@ static int ucsi_register_port(struct ucsi *ucsi, struct ucsi_connector *con) INIT_WORK(&con->work, ucsi_handle_connector_change); init_completion(&con->complete); mutex_init(&con->lock); + lockdep_set_class(&con->lock, &con->lock_key); INIT_LIST_HEAD(&con->partner_tasks); con->ucsi = ucsi; @@ -1887,6 +1888,9 @@ static int ucsi_init(struct ucsi *ucsi) goto err_reset; } + for (i = 0; i < ucsi->cap.num_connectors; i++) + lockdep_register_key(&connector[i].lock_key); + /* Register all connectors */ for (i = 0; i < ucsi->cap.num_connectors; i++) { connector[i].num = i + 1; @@ -1916,6 +1920,9 @@ static int ucsi_init(struct ucsi *ucsi) return 0; err_unregister: + for (i = 0; i < ucsi->cap.num_connectors; i++) + lockdep_unregister_key(&connector[i].lock_key); + for (con = connector; con->port; con++) { if (con->wq) destroy_workqueue(con->wq); @@ -2166,6 +2173,7 @@ void ucsi_unregister(struct ucsi *ucsi) usb_power_delivery_unregister(ucsi->connector[i].pd); ucsi->connector[i].pd = NULL; typec_unregister_port(ucsi->connector[i].port); + lockdep_unregister_key(&ucsi->connector[i].lock_key); } kfree(ucsi->connector); diff --git a/drivers/usb/typec/ucsi/ucsi.h b/drivers/usb/typec/ucsi/ucsi.h index cff9ddc2ae21..51f6c3c0d365 100644 --- a/drivers/usb/typec/ucsi/ucsi.h +++ b/drivers/usb/typec/ucsi/ucsi.h @@ -517,6 +517,7 @@ struct ucsi_connector { struct ucsi *ucsi; struct mutex lock; /* port lock */ + struct lock_class_key lock_key; struct work_struct work; struct completion complete; struct workqueue_struct *wq;