usb 1-1: DVB: registering adapter 0 frontend 0 (Toshiba TC90522 ISDB-T module)... dvbdev: dvb_create_media_entity: media entity 'Toshiba TC90522 ISDB-T module' registered. ============================================ WARNING: possible recursive locking detected 5.6.0-rc1-syzkaller #0 Not tainted -------------------------------------------- kworker/1:2/94 is trying to acquire lock: ffff8881cdf48208 (i2c_register_adapter){+.+.}, at: i2c_lock_bus include/linux/i2c.h:757 [inline] ffff8881cdf48208 (i2c_register_adapter){+.+.}, at: __i2c_lock_bus_helper drivers/i2c/i2c-core.h:44 [inline] ffff8881cdf48208 (i2c_register_adapter){+.+.}, at: i2c_transfer+0x1d3/0x3e0 drivers/i2c/i2c-core-base.c:1998 but task is already holding lock: ffff8881c40ba5c0 (i2c_register_adapter){+.+.}, at: i2c_lock_bus include/linux/i2c.h:757 [inline] ffff8881c40ba5c0 (i2c_register_adapter){+.+.}, at: __i2c_lock_bus_helper drivers/i2c/i2c-core.h:44 [inline] ffff8881c40ba5c0 (i2c_register_adapter){+.+.}, at: i2c_transfer+0x1d3/0x3e0 drivers/i2c/i2c-core-base.c:1998 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(i2c_register_adapter); lock(i2c_register_adapter); *** DEADLOCK *** May be due to missing lock nesting notation 7 locks held by kworker/1:2/94: #0: ffff8881d8eaad28 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8eaad28 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8eaad28 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8eaad28 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8eaad28 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8eaad28 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8eaad28 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2235 #1: ffff8881d5cc7dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2239 #2: ffff8881d4c7d200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d4c7d200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5499 #3: ffff8881ce503200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #3: ffff8881ce503200 (&dev->mutex){....}, at: __device_attach+0x7b/0x390 drivers/base/dd.c:874 #4: ffff8881ce504190 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #4: ffff8881ce504190 (&dev->mutex){....}, at: __device_attach+0x7b/0x390 drivers/base/dd.c:874 #5: ffff8881c40a4180 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #5: ffff8881c40a4180 (&dev->mutex){....}, at: __device_attach+0x7b/0x390 drivers/base/dd.c:874 #6: ffff8881c40ba5c0 (i2c_register_adapter){+.+.}, at: i2c_lock_bus include/linux/i2c.h:757 [inline] #6: ffff8881c40ba5c0 (i2c_register_adapter){+.+.}, at: __i2c_lock_bus_helper drivers/i2c/i2c-core.h:44 [inline] #6: ffff8881c40ba5c0 (i2c_register_adapter){+.+.}, at: i2c_transfer+0x1d3/0x3e0 drivers/i2c/i2c-core-base.c:1998 stack backtrace: CPU: 1 PID: 94 Comm: kworker/1:2 Not tainted 5.6.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: usb_hub_wq hub_event Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xef/0x16e lib/dump_stack.c:118 print_deadlock_bug kernel/locking/lockdep.c:2370 [inline] check_deadlock kernel/locking/lockdep.c:2411 [inline] validate_chain kernel/locking/lockdep.c:2954 [inline] __lock_acquire.cold+0x114/0x288 kernel/locking/lockdep.c:3954 lock_acquire+0x130/0x340 kernel/locking/lockdep.c:4484 __rt_mutex_lock kernel/locking/rtmutex.c:1471 [inline] rt_mutex_lock_nested+0x3e/0x60 kernel/locking/rtmutex.c:1484 i2c_lock_bus include/linux/i2c.h:757 [inline] __i2c_lock_bus_helper drivers/i2c/i2c-core.h:44 [inline] i2c_transfer+0x1d3/0x3e0 drivers/i2c/i2c-core-base.c:1998 tc90522_master_xfer.part.0+0x65c/0xbf0 drivers/media/dvb-frontends/tc90522.c:708 tc90522_master_xfer+0x35/0x4e drivers/media/dvb-frontends/tc90522.c:643 __i2c_transfer drivers/i2c/i2c-core-base.c:1941 [inline] __i2c_transfer+0x49d/0x17a0 drivers/i2c/i2c-core-base.c:1906 i2c_transfer+0x1e6/0x3e0 drivers/i2c/i2c-core-base.c:2002 dvb_pll_attach+0x228/0x850 drivers/media/dvb-frontends/dvb-pll.c:816 dvb_pll_probe+0xfe/0x174 drivers/media/dvb-frontends/dvb-pll.c:884 i2c_device_probe+0x51a/0x800 drivers/i2c/i2c-core-base.c:396 really_probe+0x290/0xac0 drivers/base/dd.c:551 driver_probe_device+0x223/0x350 drivers/base/dd.c:724 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:831 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431 __device_attach+0x217/0x390 drivers/base/dd.c:897 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0x1459/0x1bf0 drivers/base/core.c:2487 i2c_new_client_device+0x589/0xa70 drivers/i2c/i2c-core-base.c:784 dvb_module_probe+0xf9/0x240 drivers/media/dvb-core/dvbdev.c:986 friio_tuner_attach+0x12b/0x1d0 drivers/media/usb/dvb-usb-v2/gl861.c:457 dvb_usbv2_adapter_frontend_init drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:676 [inline] dvb_usbv2_adapter_init drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:805 [inline] dvb_usbv2_init drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:866 [inline] dvb_usbv2_probe.cold+0x2dd2/0x2efe drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:981 usb_probe_interface+0x310/0x800 drivers/usb/core/driver.c:374 really_probe+0x290/0xac0 drivers/base/dd.c:551 driver_probe_device+0x223/0x350 drivers/base/dd.c:724 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:831 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431 __device_attach+0x217/0x390 drivers/base/dd.c:897 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0x1459/0x1bf0 drivers/base/core.c:2487 usb_set_configuration+0xe47/0x17d0 drivers/usb/core/message.c:2023 usb_generic_driver_probe+0x9d/0xe0 drivers/usb/core/generic.c:241 usb_probe_device+0xd9/0x230 drivers/usb/core/driver.c:272 really_probe+0x290/0xac0 drivers/base/dd.c:551 driver_probe_device+0x223/0x350 drivers/base/dd.c:724 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:831 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431 __device_attach+0x217/0x390 drivers/base/dd.c:897 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0x1459/0x1bf0 drivers/base/core.c:2487 usb_new_device.cold+0x540/0xcd0 drivers/usb/core/hub.c:2538 hub_port_connect drivers/usb/core/hub.c:5185 [inline] hub_port_connect_change drivers/usb/core/hub.c:5325 [inline] port_event drivers/usb/core/hub.c:5471 [inline] hub_event+0x21cb/0x4300 drivers/usb/core/hub.c:5553 process_one_work+0x94b/0x1620 kernel/workqueue.c:2264 worker_thread+0x96/0xe20 kernel/workqueue.c:2410 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 dvb_pll: probe of 1-0060 failed with error -12 usbhid 1-1:0.0: couldn't find an input interrupt endpoint usb 1-1: USB disconnect, device number 2 usb 1-1: new high-speed USB device number 3 using dummy_hcd usb 1-1: Using ep0 maxpacket: 16 usb 1-1: New USB device found, idVendor=7a69, idProduct=0001, bcdDevice=92.73 usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0 usb 1-1: config 0 descriptor?? usb 1-1: dvb_usb_v2: found a '774 Friio White ISDB-T USB2.0' in warm state usb 1-1: dvb_usb_v2: will pass the complete MPEG2 transport stream to the software demuxer dvbdev: DVB: registering new adapter (774 Friio White ISDB-T USB2.0) usb 1-1: media controller created dvbdev: dvb_create_media_entity: media entity 'dvb-demux' registered. tc90522 0-0018: Toshiba TC90522 attached. usb 1-1: DVB: registering adapter 0 frontend 0 (Toshiba TC90522 ISDB-T module)... dvbdev: dvb_create_media_entity: media entity 'Toshiba TC90522 ISDB-T module' registered. dvb_pll: probe of 1-0060 failed with error -12 usbhid 1-1:0.0: couldn't find an input interrupt endpoint usb 1-1: USB disconnect, device number 3 usb 1-1: new high-speed USB device number 4 using dummy_hcd usb 1-1: Using ep0 maxpacket: 16 usb 1-1: New USB device found, idVendor=7a69, idProduct=0001, bcdDevice=92.73 usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0 usb 1-1: config 0 descriptor?? usb 1-1: dvb_usb_v2: found a '774 Friio White ISDB-T USB2.0' in warm state usb 1-1: dvb_usb_v2: will pass the complete MPEG2 transport stream to the software demuxer dvbdev: DVB: registering new adapter (774 Friio White ISDB-T USB2.0) usb 1-1: media controller created dvbdev: dvb_create_media_entity: media entity 'dvb-demux' registered. tc90522 0-0018: Toshiba TC90522 attached. usb 1-1: DVB: registering adapter 0 frontend 0 (Toshiba TC90522 ISDB-T module)... dvbdev: dvb_create_media_entity: media entity 'Toshiba TC90522 ISDB-T module' registered. dvb_pll: probe of 1-0060 failed with error -12 usbhid 1-1:0.0: couldn't find an input interrupt endpoint usb 1-1: USB disconnect, device number 4 usb 1-1: new high-speed USB device number 5 using dummy_hcd usb 1-1: Using ep0 maxpacket: 16 usb 1-1: New USB device found, idVendor=7a69, idProduct=0001, bcdDevice=92.73 usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0 usb 1-1: config 0 descriptor?? usb 1-1: dvb_usb_v2: found a '774 Friio White ISDB-T USB2.0' in warm state usb 1-1: dvb_usb_v2: will pass the complete MPEG2 transport stream to the software demuxer dvbdev: DVB: registering new adapter (774 Friio White ISDB-T USB2.0) usb 1-1: media controller created dvbdev: dvb_create_media_entity: media entity 'dvb-demux' registered. tc90522 10-0018: Toshiba TC90522 attached. usb 1-1: DVB: registering adapter 5 frontend 0 (Toshiba TC90522 ISDB-T module)... dvbdev: dvb_create_media_entity: media entity 'Toshiba TC90522 ISDB-T module' registered. dvb_pll: probe of 11-0060 failed with error -12 usbhid 1-1:0.0: couldn't find an input interrupt endpoint usb 1-1: USB disconnect, device number 5 usb 1-1: new high-speed USB device number 6 using dummy_hcd usb 1-1: Using ep0 maxpacket: 16 usb 1-1: New USB device found, idVendor=7a69, idProduct=0001, bcdDevice=92.73 usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0 usb 1-1: config 0 descriptor?? usb 1-1: dvb_usb_v2: found a '774 Friio White ISDB-T USB2.0' in warm state usb 1-1: dvb_usb_v2: will pass the complete MPEG2 transport stream to the software demuxer dvbdev: DVB: registering new adapter (774 Friio White ISDB-T USB2.0) usb 1-1: media controller created dvbdev: dvb_create_media_entity: media entity 'dvb-demux' registered. tc90522 0-0018: Toshiba TC90522 attached. usb 1-1: DVB: registering adapter 0 frontend 0 (Toshiba TC90522 ISDB-T module)... dvbdev: dvb_create_media_entity: media entity 'Toshiba TC90522 ISDB-T module' registered. dvb_pll: probe of 6-0060 failed with error -12 usbhid 1-1:0.0: couldn't find an input interrupt endpoint usb 1-1: USB disconnect, device number 6 usb 1-1: new high-speed USB device number 7 using dummy_hcd usb 1-1: Using ep0 maxpacket: 16 usb 1-1: New USB device found, idVendor=7a69, idProduct=0001, bcdDevice=92.73 usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0 usb 1-1: config 0 descriptor?? usb 1-1: dvb_usb_v2: found a '774 Friio White ISDB-T USB2.0' in warm state usb 1-1: dvb_usb_v2: will pass the complete MPEG2 transport stream to the software demuxer dvbdev: DVB: registering new adapter (774 Friio White ISDB-T USB2.0) usb 1-1: media controller created dvbdev: dvb_create_media_entity: media entity 'dvb-demux' registered. tc90522 0-0018: Toshiba TC90522 attached. usb 1-1: DVB: registering adapter 0 frontend 0 (Toshiba TC90522 ISDB-T module)... dvbdev: dvb_create_media_entity: media entity 'Toshiba TC90522 ISDB-T module' registered. dvb_pll: probe of 1-0060 failed with error -12 usbhid 1-1:0.0: couldn't find an input interrupt endpoint usb 1-1: USB disconnect, device number 7 usb 1-1: new high-speed USB device number 8 using dummy_hcd usb 1-1: Using ep0 maxpacket: 16 usb 1-1: New USB device found, idVendor=7a69, idProduct=0001, bcdDevice=92.73 usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0 usb 1-1: config 0 descriptor?? usb 1-1: dvb_usb_v2: found a '774 Friio White ISDB-T USB2.0' in warm state usb 1-1: dvb_usb_v2: will pass the complete MPEG2 transport stream to the software demuxer dvbdev: DVB: registering new adapter (774 Friio White ISDB-T USB2.0) usb 1-1: media controller created dvbdev: dvb_create_media_entity: media entity 'dvb-demux' registered. tc90522 0-0018: Toshiba TC90522 attached. usb 1-1: DVB: registering adapter 0 frontend 0 (Toshiba TC90522 ISDB-T module)... dvbdev: dvb_create_media_entity: media entity 'Toshiba TC90522 ISDB-T module' registered. dvb_pll: probe of 1-0060 failed with error -12 usbhid 1-1:0.0: couldn't find an input interrupt endpoint usb 1-1: USB disconnect, device number 8 usb 1-1: new high-speed USB device number 9 using dummy_hcd usb 1-1: Using ep0 maxpacket: 16 usb 1-1: New USB device found, idVendor=7a69, idProduct=0001, bcdDevice=92.73 usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0 usb 1-1: config 0 descriptor?? usb 1-1: dvb_usb_v2: found a '774 Friio White ISDB-T USB2.0' in warm state usb 1-1: dvb_usb_v2: will pass the complete MPEG2 transport stream to the software demuxer dvbdev: DVB: registering new adapter (774 Friio White ISDB-T USB2.0) usb 1-1: media controller created dvbdev: dvb_create_media_entity: media entity 'dvb-demux' registered. tc90522 0-0018: Toshiba TC90522 attached. usb 1-1: DVB: registering adapter 4 frontend 0 (Toshiba TC90522 ISDB-T module)... dvbdev: dvb_create_media_entity: media entity 'Toshiba TC90522 ISDB-T module' registered. dvb_pll: probe of 7-0060 failed with error -12 usbhid 1-1:0.0: couldn't find an input interrupt endpoint usb 1-1: USB disconnect, device number 9 usb 1-1: new high-speed USB device number 10 using dummy_hcd usb 1-1: Using ep0 maxpacket: 16 usb 1-1: New USB device found, idVendor=7a69, idProduct=0001, bcdDevice=92.73 usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0 usb 1-1: config 0 descriptor?? usb 1-1: dvb_usb_v2: found a '774 Friio White ISDB-T USB2.0' in warm state usb 1-1: dvb_usb_v2: will pass the complete MPEG2 transport stream to the software demuxer dvbdev: DVB: registering new adapter (774 Friio White ISDB-T USB2.0) usb 1-1: media controller created dvbdev: dvb_create_media_entity: media entity 'dvb-demux' registered. tc90522 1-0018: Toshiba TC90522 attached. usb 1-1: DVB: registering adapter 0 frontend 0 (Toshiba TC90522 ISDB-T module)... dvbdev: dvb_create_media_entity: media entity 'Toshiba TC90522 ISDB-T module' registered. dvb_pll: probe of 7-0060 failed with error -12