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Sergey Senozhatsky
c888e052a0
[ Upstream commit8c22256bba] 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] <TASK> [ 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] </TASK> [ 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 <senozhatsky@chromium.org> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Link: https://patch.msgid.link/20260515060042.136083-1-senozhatsky@chromium.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Stable-dep-of:7aa7d4bf9d("usb: typec: ucsi: Fix race condition and ordering in port unregistration") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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