https://bugzilla.kernel.org/show_bug.cgi?id=215746 Bug ID: 215746 Summary: rfcomm: WARNING: possible circular locking dependency detected: rfcomm_sk_state_change <-> rfcomm_run Product: Drivers Version: 2.5 Kernel Version: 5.17 Hardware: All OS: Linux Tree: Mainline Status: NEW Severity: normal Priority: P1 Component: Bluetooth Assignee: linux-bluetooth@xxxxxxxxxxxxxxx Reporter: travneff@xxxxxxxxx Regression: No Created attachment 300617 --> https://bugzilla.kernel.org/attachment.cgi?id=300617&action=edit my changes on 5.17 I have this kernel trace often while connecting bluetooth headphones: WARNING: possible circular locking dependency detected 5.17.0+ #1 Tainted: G W ------------------------------------------------------ krfcommd/2671 is trying to acquire lock: ffff9c11062c7940 (sk_lock-AF_BLUETOOTH-BTPROTO_RFCOMM){+.+.}-{0:0}, at: rfcomm_sk_state_change+0x4d/0x120 [rfcomm] but task is already holding lock: ffff9c10a0360f40 (&d->lock){+.+.}-{3:3}, at: rfcomm_run+0x1342/0x1860 [rfcomm] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&d->lock){+.+.}-{3:3}: __mutex_lock+0x93/0x840 rfcomm_run+0x1342/0x1860 [rfcomm] kthread+0xf5/0x120 ret_from_fork+0x22/0x30 -> #1 (rfcomm_mutex){+.+.}-{3:3}: __mutex_lock+0x93/0x840 rfcomm_dlc_open+0x30/0x340 [rfcomm] rfcomm_sock_connect+0xd5/0x130 [rfcomm] __sys_connect+0xb9/0xe0 __x64_sys_connect+0x14/0x20 do_syscall_64+0x3a/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #0 (sk_lock-AF_BLUETOOTH-BTPROTO_RFCOMM){+.+.}-{0:0}: __lock_acquire+0x1429/0x2410 lock_acquire+0xc3/0x2c0 lock_sock_nested+0x2e/0x80 rfcomm_sk_state_change+0x4d/0x120 [rfcomm] rfcomm_run+0x135e/0x1860 [rfcomm] kthread+0xf5/0x120 ret_from_fork+0x22/0x30 other info that might help us debug this: Chain exists of: sk_lock-AF_BLUETOOTH-BTPROTO_RFCOMM --> rfcomm_mutex --> &d->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&d->lock); lock(rfcomm_mutex); lock(&d->lock); lock(sk_lock-AF_BLUETOOTH-BTPROTO_RFCOMM); *** DEADLOCK *** 2 locks held by krfcommd/2671: #0: ffffffffc0acf130 (rfcomm_mutex){+.+.}-{3:3}, at: rfcomm_run+0x135/0x1860 [rfcomm] #1: ffff9c10a0360f40 (&d->lock){+.+.}-{3:3}, at: rfcomm_run+0x1342/0x1860 [rfcomm] stack backtrace: CPU: 5 PID: 2671 Comm: krfcommd Tainted: G W 5.17.0+ #1 Hardware name: ASUS System Product Name/TUF GAMING B550M-PLUS, BIOS 2423 08/10/2021 Call Trace: <TASK> dump_stack_lvl+0x4c/0x60 check_noncircular+0xe0/0x100 __lock_acquire+0x1429/0x2410 lock_acquire+0xc3/0x2c0 ? rfcomm_sk_state_change+0x4d/0x120 [rfcomm] ? rfcomm_run+0x1342/0x1860 [rfcomm] lock_sock_nested+0x2e/0x80 ? rfcomm_sk_state_change+0x4d/0x120 [rfcomm] rfcomm_sk_state_change+0x4d/0x120 [rfcomm] rfcomm_run+0x135e/0x1860 [rfcomm] ? __init_waitqueue_head+0x60/0x60 ? _raw_spin_unlock_irqrestore+0x3b/0x60 ? rfcomm_check_accept+0xa0/0xa0 [rfcomm] kthread+0xf5/0x120 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x22/0x30 </TASK> Kernel is tainted because of another bug: https://bugzilla.kernel.org/show_bug.cgi?id=215740 BT hardware: ID 0b05:17cb ASUSTek Computer, Inc. Broadcom BCM20702A0 Bluetooth Kernel is built from https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git at v5.17 tag (f443e374ae131c168a065ea1748feac6b2e76613) with couple of simple changes, adding them here just in case. Also reproduces for my distro kernel: https://bugzilla.redhat.com/show_bug.cgi?id=1948294 -- You may reply to this email to add a comment. You are receiving this mail because: You are the assignee for the bug.
