Michael Buesch wrote: > > So it's a lock dependency between rfkill->mutex and wl->mutex? > So, now comes the question that really matters. Who is the caller > of rfkill_toggle_radio, in the case where it crashes? > Here is the full dump. It looks to me as if b43_rfkill_soft_toggle() calls rfkill_handler(), which calls rfkill_toggle_radio() and it is calling b43_rfkill_soft_toggle(). I'd call that a loop. kernel: kernel: ======================================================= kernel: [ INFO: possible circular locking dependency detected ] kernel: 2.6.24-rc3-L2.6-g65d438bf-dirty #24 kernel: ------------------------------------------------------- kernel: events/0/9 is trying to acquire lock: kernel: (&wl->mutex){--..}, at: [<ffffffff882a31e1>] b43_rfkill_soft_toggle+0x33/0xb2 [b43] kernel: kernel: but task is already holding lock: kernel: (&rfkill->mutex){--..}, at: [<ffffffff8040b927>] rfkill_toggle_radio+0x1f/0x7d kernel: kernel: which lock already depends on the new lock. kernel: kernel: kernel: the existing dependency chain (in reverse order) is: kernel: kernel: -> #2 (&rfkill->mutex){--..}: kernel: [<ffffffff8025951c>] __lock_acquire+0xb34/0xd47 kernel: [<ffffffff8040b927>] rfkill_toggle_radio+0x1f/0x7d kernel: [<ffffffff802597b4>] lock_acquire+0x85/0xa9 kernel: [<ffffffff8040b927>] rfkill_toggle_radio+0x1f/0x7d kernel: [<ffffffff8040e32e>] mutex_lock_interruptible_nested+0x113/0x31e kernel: [<ffffffff8040b927>] rfkill_toggle_radio+0x1f/0x7d kernel: [<ffffffff8040b927>] rfkill_toggle_radio+0x1f/0x7d kernel: [<ffffffff8040bd64>] rfkill_register+0x9b/0x107 kernel: [<ffffffff882a3040>] b43_rfkill_init+0x15e/0x1cb [b43] kernel: [<ffffffff88293ad4>] b43_wireless_core_init+0x682/0x784 [b43] kernel: [<ffffffff882948a6>] b43_op_start+0x33/0x74 [b43] kernel: [<ffffffff881f2a76>] ieee80211_open+0x1c7/0x3dd [mac80211] kernel: [<ffffffff803b2fda>] dev_open+0x4e/0x88 kernel: [<ffffffff803b18a2>] dev_change_flags+0xaf/0x16b kernel: [<ffffffff803b9f9d>] do_setlink+0x27a/0x346 kernel: [<ffffffff8040fa9c>] _read_unlock+0x26/0x2b kernel: [<ffffffff803bb233>] rtnl_setlink+0xf9/0x11c kernel: [<ffffffff803bb0d3>] rtnetlink_rcv_msg+0x1b6/0x1d5 kernel: [<ffffffff803baf1d>] rtnetlink_rcv_msg+0x0/0x1d5 kernel: [<ffffffff803c36a5>] netlink_rcv_skb+0x3e/0xaa kernel: [<ffffffff803baf14>] rtnetlink_rcv+0x20/0x29 kernel: [<ffffffff803c344c>] netlink_unicast+0x1d9/0x23a kernel: [<ffffffff803ac19e>] __alloc_skb+0x8a/0x138 kernel: [<ffffffff803c3c79>] netlink_sendmsg+0x2aa/0x2bd kernel: [<ffffffff803a6249>] sock_sendmsg+0xdf/0xf8 kernel: [<ffffffff8024db89>] autoremove_wake_function+0x0/0x38 kernel: [<ffffffff8024db89>] autoremove_wake_function+0x0/0x38 kernel: [<ffffffff8025970e>] __lock_acquire+0xd26/0xd47 kernel: [<ffffffff803a6b7f>] move_addr_to_kernel+0x40/0x49 kernel: [<ffffffff803ad5b9>] verify_iovec+0x4f/0x8e kernel: [<ffffffff803a6443>] sys_sendmsg+0x1e1/0x253 kernel: [<ffffffff80250916>] up_read+0x26/0x2a kernel: [<ffffffff8022581f>] do_page_fault+0x3bf/0x764 kernel: [<ffffffff803a72c4>] sys_getsockname+0x66/0x8c kernel: [<ffffffff80258540>] trace_hardirqs_on+0x11c/0x147 kernel: [<ffffffff8040f5b8>] trace_hardirqs_on_thunk+0x35/0x3a kernel: [<ffffffff8020c0de>] system_call+0x7e/0x83 kernel: [<ffffffffffffffff>] 0xffffffffffffffff kernel: kernel: -> #1 (rfkill_mutex){--..}: kernel: [<ffffffff8025951c>] __lock_acquire+0xb34/0xd47 kernel: [<ffffffff8040bd50>] rfkill_register+0x87/0x107 kernel: [<ffffffff802597b4>] lock_acquire+0x85/0xa9 kernel: [<ffffffff8040bd50>] rfkill_register+0x87/0x107 kernel: [<ffffffff8040bd50>] rfkill_register+0x87/0x107 kernel: [<ffffffff8040e78a>] mutex_lock_nested+0x10e/0x2b6 kernel: [<ffffffff8040bd50>] rfkill_register+0x87/0x107 kernel: [<ffffffff882a3040>] b43_rfkill_init+0x15e/0x1cb [b43] kernel: [<ffffffff88293ad4>] b43_wireless_core_init+0x682/0x784 [b43] kernel: [<ffffffff882948a6>] b43_op_start+0x33/0x74 [b43] kernel: [<ffffffff881f2a76>] ieee80211_open+0x1c7/0x3dd [mac80211] kernel: [<ffffffff803b2fda>] dev_open+0x4e/0x88 kernel: [<ffffffff803b18a2>] dev_change_flags+0xaf/0x16b kernel: [<ffffffff803b9f9d>] do_setlink+0x27a/0x346 kernel: [<ffffffff8040fa9c>] _read_unlock+0x26/0x2b kernel: [<ffffffff803bb233>] rtnl_setlink+0xf9/0x11c kernel: [<ffffffff803bb0d3>] rtnetlink_rcv_msg+0x1b6/0x1d5 kernel: [<ffffffff803baf1d>] rtnetlink_rcv_msg+0x0/0x1d5 kernel: [<ffffffff803c36a5>] netlink_rcv_skb+0x3e/0xaa kernel: [<ffffffff803baf14>] rtnetlink_rcv+0x20/0x29 kernel: [<ffffffff803c344c>] netlink_unicast+0x1d9/0x23a kernel: [<ffffffff803ac19e>] __alloc_skb+0x8a/0x138 kernel: [<ffffffff803c3c79>] netlink_sendmsg+0x2aa/0x2bd kernel: [<ffffffff803a6249>] sock_sendmsg+0xdf/0xf8 kernel: [<ffffffff8024db89>] autoremove_wake_function+0x0/0x38 kernel: [<ffffffff8024db89>] autoremove_wake_function+0x0/0x38 kernel: [<ffffffff8025970e>] __lock_acquire+0xd26/0xd47 kernel: [<ffffffff803a6b7f>] move_addr_to_kernel+0x40/0x49 kernel: [<ffffffff803ad5b9>] verify_iovec+0x4f/0x8e kernel: [<ffffffff803a6443>] sys_sendmsg+0x1e1/0x253 kernel: [<ffffffff80250916>] up_read+0x26/0x2a kernel: [<ffffffff8022581f>] do_page_fault+0x3bf/0x764 kernel: [<ffffffff803a72c4>] sys_getsockname+0x66/0x8c kernel: [<ffffffff80258540>] trace_hardirqs_on+0x11c/0x147 kernel: [<ffffffff8040f5b8>] trace_hardirqs_on_thunk+0x35/0x3a kernel: [<ffffffff8020c0de>] system_call+0x7e/0x83 kernel: [<ffffffffffffffff>] 0xffffffffffffffff kernel: kernel: -> #0 (&wl->mutex){--..}: kernel: [<ffffffff80256dd7>] print_circular_bug_entry+0x48/0x4f kernel: [<ffffffff8025941e>] __lock_acquire+0xa36/0xd47 kernel: [<ffffffff882a31e1>] b43_rfkill_soft_toggle+0x33/0xb2 [b43] kernel: [<ffffffff802597b4>] lock_acquire+0x85/0xa9 kernel: [<ffffffff882a31e1>] b43_rfkill_soft_toggle+0x33/0xb2 [b43] kernel: [<ffffffff882a31e1>] b43_rfkill_soft_toggle+0x33/0xb2 [b43] kernel: [<ffffffff8040e78a>] mutex_lock_nested+0x10e/0x2b6 kernel: [<ffffffff8040b927>] rfkill_toggle_radio+0x1f/0x7d kernel: [<ffffffff8040bf6f>] rfkill_task_handler+0x0/0x54 kernel: [<ffffffff882a31e1>] b43_rfkill_soft_toggle+0x33/0xb2 [b43] kernel: [<ffffffff8040b944>] rfkill_toggle_radio+0x3c/0x7d kernel: [<ffffffff8040be96>] rfkill_switch_all+0x3e/0x78 kernel: [<ffffffff8040bfab>] rfkill_task_handler+0x3c/0x54 kernel: [<ffffffff80249914>] run_workqueue+0xeb/0x200 kernel: [<ffffffff8024a500>] worker_thread+0xed/0xfe kernel: [<ffffffff8024db89>] autoremove_wake_function+0x0/0x38 kernel: [<ffffffff8024a413>] worker_thread+0x0/0xfe kernel: [<ffffffff8024da6e>] kthread+0x49/0x77 kernel: [<ffffffff8020d018>] child_rip+0xa/0x12 kernel: [<ffffffff8020c72f>] restore_args+0x0/0x30 kernel: [<ffffffff8024da25>] kthread+0x0/0x77 kernel: [<ffffffff8020d00e>] child_rip+0x0/0x12 kernel: [<ffffffffffffffff>] 0xffffffffffffffff kernel: kernel: other info that might help us debug this: kernel: kernel: 5 locks held by events/0/9: kernel: #0: (events){--..}, at: [<ffffffff802498c9>] run_workqueue+0xa0/0x200 kernel: #1: (rfkill_wlan.work){--..}, at: [<ffffffff802498c9>] run_workqueue+0xa0/0x200 kernel: #2: (rfkill_wlan.mutex){--..}, at: [<ffffffff8040bf8d>] rfkill_task_handler+0x1e/0x54 kernel: #3: (rfkill_mutex){--..}, at: [<ffffffff8040be74>] rfkill_switch_all+0x1c/0x78 kernel: #4: (&rfkill->mutex){--..}, at: [<ffffffff8040b927>] rfkill_toggle_radio+0x1f/0x7d kernel: kernel: stack backtrace: kernel: kernel: Call Trace: kernel: [<ffffffff8025779c>] print_circular_bug_tail+0x70/0x7b kernel: [<ffffffff80256dd7>] print_circular_bug_entry+0x48/0x4f kernel: [<ffffffff8025941e>] __lock_acquire+0xa36/0xd47 kernel: [<ffffffff882a31e1>] :b43:b43_rfkill_soft_toggle+0x33/0xb2 kernel: [<ffffffff802597b4>] lock_acquire+0x85/0xa9 kernel: [<ffffffff882a31e1>] :b43:b43_rfkill_soft_toggle+0x33/0xb2 kernel: [<ffffffff882a31e1>] :b43:b43_rfkill_soft_toggle+0x33/0xb2 kernel: [<ffffffff8040e78a>] mutex_lock_nested+0x10e/0x2b6 kernel: [<ffffffff8040b927>] rfkill_toggle_radio+0x1f/0x7d kernel: [<ffffffff8040bf6f>] rfkill_task_handler+0x0/0x54 kernel: [<ffffffff882a31e1>] :b43:b43_rfkill_soft_toggle+0x33/0xb2 kernel: [<ffffffff8040b944>] rfkill_toggle_radio+0x3c/0x7d kernel: [<ffffffff8040be96>] rfkill_switch_all+0x3e/0x78 kernel: [<ffffffff8040bfab>] rfkill_task_handler+0x3c/0x54 kernel: [<ffffffff80249914>] run_workqueue+0xeb/0x200 kernel: [<ffffffff8024a500>] worker_thread+0xed/0xfe kernel: [<ffffffff8024db89>] autoremove_wake_function+0x0/0x38 kernel: [<ffffffff8024a413>] worker_thread+0x0/0xfe kernel: [<ffffffff8024da6e>] kthread+0x49/0x77 kernel: [<ffffffff8020d018>] child_rip+0xa/0x12 kernel: [<ffffffff8020c72f>] restore_args+0x0/0x30 kernel: [<ffffffff8024da25>] kthread+0x0/0x77 kernel: [<ffffffff8020d00e>] child_rip+0x0/0x12 - To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html