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INFO: rcu detected stall in hci_cmd_timeout (2)

Status: auto-obsoleted due to no activity on 2025/03/16 00:29
Subsystems: bluetooth
[Documentation on labels]
First crash: 100d, last: 100d
▶ ▼ Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in hci_cmd_timeout bluetooth 1 593d 593d 23/28 fixed on 2023/10/12 12:47
upstream BUG: soft lockup in hci_cmd_timeout bluetooth usb C 1 291d 287d 26/28 fixed on 2024/07/09 19:14
upstream BUG: soft lockup in hci_cmd_timeout (2) bluetooth usb syz 1 10d 6d03h 0/28 upstream: reported syz repro on 2025/03/20 09:07

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=d284/1/0x4000000000000000 softirq=35775/35776 fqs=0
rcu: 	(detected by 1, t=10502 jiffies, g=23513, q=368 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5819 Comm: kworker/u9:2 Not tainted 6.13.0-rc2-syzkaller-00362-g2d8308bf5b67 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024
Workqueue: hci1 hci_cmd_timeout
RIP: 0010:__lock_is_held kernel/locking/lockdep.c:5587 [inline]
RIP: 0010:lock_is_held_type+0x87/0x150 kernel/locking/lockdep.c:5921
Code: 6c 8b 45 31 ff e8 09 17 00 00 4d 8d ac 24 e0 0a 00 00 65 ff 05 a2 73 d9 74 41 8b 84 24 d8 0a 00 00 85 c0 7f 17 e9 92 00 00 00 <41> 83 c7 01 45 3b bc 24 d8 0a 00 00 0f 8d 80 00 00 00 49 63 c7 48
RSP: 0018:ffffc90000007d40 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff88805fc48b30 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffff88805a949300 RDI: ffff88805fc48b30
RBP: ffff88805a949300 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000004 R12: ffff88805fc48000
R13: ffff88805fc48ae0 R14: 00000000ffffffff R15: 0000000000000002
FS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2e624a CR3: 000000005af24000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 lock_is_held include/linux/lockdep.h:249 [inline]
 advance_sched+0x790/0xc60 net/sched/sch_taprio.c:927
 __run_hrtimer kernel/time/hrtimer.c:1739 [inline]
 __hrtimer_run_queues+0x20a/0xae0 kernel/time/hrtimer.c:1803
 hrtimer_interrupt+0x392/0x8e0 kernel/time/hrtimer.c:1865
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x10f/0x400 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:console_flush_all+0x9a4/0xc60 kernel/printk/printk.c:3211
Code: 00 e8 d0 15 28 00 9c 5b 81 e3 00 02 00 00 31 ff 48 89 de e8 8e 66 20 00 48 85 db 0f 85 55 01 00 00 e8 10 64 20 00 fb 4c 89 e0 <48> c1 e8 03 42 80 3c 38 00 0f 84 11 ff ff ff 4c 89 e7 e8 45 12 83
RSP: 0018:ffffc90003617840 EFLAGS: 00000293
RAX: ffffffff8ee92df8 RBX: 0000000000000000 RCX: ffffffff81799f62
RDX: ffff88805fc48000 RSI: ffffffff81799f70 RDI: 0000000000000007
RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000005 R12: ffffffff8ee92df8
R13: ffffffff8ee92da0 R14: ffffc900036178d0 R15: dffffc0000000000
 __console_flush_and_unlock kernel/printk/printk.c:3269 [inline]
 console_unlock+0xd9/0x210 kernel/printk/printk.c:3309
 vprintk_emit+0x424/0x6f0 kernel/printk/printk.c:2432
 vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:86
 _printk+0xc8/0x100 kernel/printk/printk.c:2457
 bt_err+0xe5/0x120 net/bluetooth/lib.c:296
 hci_cmd_timeout+0x1ff/0x260 net/bluetooth/hci_core.c:1456
 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229
 process_scheduled_works kernel/workqueue.c:3310 [inline]
 worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: rcu_preempt kthread starved for 10502 jiffies! g23513 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:27600 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756
 __schedule_loop kernel/sched/core.c:6833 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6848
 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2045
 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2247
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 8646 Comm: syz-executor Not tainted 6.13.0-rc2-syzkaller-00362-g2d8308bf5b67 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_single+0x1c7/0x580 kernel/smp.c:679
Code: c0 48 89 de 89 fa c1 e2 10 09 d0 89 44 24 4c e8 af fa ff ff 41 89 c5 0f 1f 44 00 00 e8 32 f3 0b 00 eb 07 e8 2b f3 0b 00 f3 90 <8b> 5c 24 48 31 ff 83 e3 01 89 de e8 59 f5 0b 00 85 db 75 e5 e8 10
RSP: 0018:ffffc9000b9af6c0 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff818e1067
RDX: ffff8880658ec880 RSI: ffffffff818e1055 RDI: 0000000000000005
RBP: ffffc9000b9af788 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000007 R12: 1ffff92001735edc
R13: 0000000000000000 R14: 0000000000000001 R15: ffff8880b863fb80
FS:  000055558ca1e500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0566969ae0 CR3: 0000000036af8000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 rcu_barrier+0x28d/0x700 kernel/rcu/tree.c:4617
 netdev_run_todo+0x2eb/0x12d0 net/core/dev.c:10890
 nsim_destroy+0x181/0x6b0 drivers/net/netdevsim/netdev.c:828
 __nsim_dev_port_del+0x189/0x240 drivers/net/netdevsim/dev.c:1428
 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1440 [inline]
 nsim_dev_reload_destroy+0x108/0x4d0 drivers/net/netdevsim/dev.c:1661
 nsim_drv_remove+0x52/0x1d0 drivers/net/netdevsim/dev.c:1676
 device_remove+0xc8/0x170 drivers/base/dd.c:567
 __device_release_driver drivers/base/dd.c:1273 [inline]
 device_release_driver_internal+0x44a/0x610 drivers/base/dd.c:1296
 bus_remove_device+0x22f/0x420 drivers/base/bus.c:576
 device_del+0x396/0x9f0 drivers/base/core.c:3854
 device_unregister+0x1d/0xc0 drivers/base/core.c:3895
 nsim_bus_dev_del drivers/net/netdevsim/bus.c:462 [inline]
 del_device_store+0x346/0x4b0 drivers/net/netdevsim/bus.c:226
 bus_attr_store+0x71/0xb0 drivers/base/bus.c:172
 sysfs_kf_write+0x117/0x170 fs/sysfs/file.c:139
 kernfs_fop_write_iter+0x33d/0x500 fs/kernfs/file.c:334
 new_sync_write fs/read_write.c:586 [inline]
 vfs_write+0x5ae/0x1150 fs/read_write.c:679
 ksys_write+0x12b/0x250 fs/read_write.c:731
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0ea0d847cf
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48
RSP: 002b:00007ffd32cdd4d0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007f0ea0d847cf
RDX: 0000000000000001 RSI: 00007ffd32cdd520 RDI: 0000000000000005
RBP: 00007f0ea0e02c2d R08: 0000000000000000 R09: 00007ffd32cdd327
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001
R13: 00007ffd32cdd520 R14: 00007f0ea1aa4620 R15: 0000000000000003
 </TASK>
watchdog: BUG: soft lockup - CPU#1 stuck for 246s! [syz-executor:8646]
Modules linked in:
irq event stamp: 20471402
hardirqs last  enabled at (20471401): [<ffffffff8b29224b>] irqentry_exit+0x3b/0x90 kernel/entry/common.c:357
hardirqs last disabled at (20471402): [<ffffffff8b2909ce>] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1049
softirqs last  enabled at (20471400): [<ffffffff815c517b>] softirq_handle_end kernel/softirq.c:407 [inline]
softirqs last  enabled at (20471400): [<ffffffff815c517b>] handle_softirqs+0x5bb/0x8f0 kernel/softirq.c:589
softirqs last disabled at (20471391): [<ffffffff815c5649>] __do_softirq kernel/softirq.c:595 [inline]
softirqs last disabled at (20471391): [<ffffffff815c5649>] invoke_softirq kernel/softirq.c:435 [inline]
softirqs last disabled at (20471391): [<ffffffff815c5649>] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:662
CPU: 1 UID: 0 PID: 8646 Comm: syz-executor Not tainted 6.13.0-rc2-syzkaller-00362-g2d8308bf5b67 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_single+0x1c7/0x580 kernel/smp.c:679
Code: c0 48 89 de 89 fa c1 e2 10 09 d0 89 44 24 4c e8 af fa ff ff 41 89 c5 0f 1f 44 00 00 e8 32 f3 0b 00 eb 07 e8 2b f3 0b 00 f3 90 <8b> 5c 24 48 31 ff 83 e3 01 89 de e8 59 f5 0b 00 85 db 75 e5 e8 10
RSP: 0018:ffffc9000b9af6c0 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff818e1067
RDX: ffff8880658ec880 RSI: ffffffff818e1055 RDI: 0000000000000005
RBP: ffffc9000b9af788 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000007 R12: 1ffff92001735edc
R13: 0000000000000000 R14: 0000000000000001 R15: ffff8880b863fb80
FS:  000055558ca1e500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0566969ae0 CR3: 0000000036af8000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 rcu_barrier+0x28d/0x700 kernel/rcu/tree.c:4617
 netdev_run_todo+0x2eb/0x12d0 net/core/dev.c:10890
 nsim_destroy+0x181/0x6b0 drivers/net/netdevsim/netdev.c:828
 __nsim_dev_port_del+0x189/0x240 drivers/net/netdevsim/dev.c:1428
 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1440 [inline]
 nsim_dev_reload_destroy+0x108/0x4d0 drivers/net/netdevsim/dev.c:1661
 nsim_drv_remove+0x52/0x1d0 drivers/net/netdevsim/dev.c:1676
 device_remove+0xc8/0x170 drivers/base/dd.c:567
 __device_release_driver drivers/base/dd.c:1273 [inline]
 device_release_driver_internal+0x44a/0x610 drivers/base/dd.c:1296
 bus_remove_device+0x22f/0x420 drivers/base/bus.c:576
 device_del+0x396/0x9f0 drivers/base/core.c:3854
 device_unregister+0x1d/0xc0 drivers/base/core.c:3895
 nsim_bus_dev_del drivers/net/netdevsim/bus.c:462 [inline]
 del_device_store+0x346/0x4b0 drivers/net/netdevsim/bus.c:226
 bus_attr_store+0x71/0xb0 drivers/base/bus.c:172
 sysfs_kf_write+0x117/0x170 fs/sysfs/file.c:139
 kernfs_fop_write_iter+0x33d/0x500 fs/kernfs/file.c:334
 new_sync_write fs/read_write.c:586 [inline]
 vfs_write+0x5ae/0x1150 fs/read_write.c:679
 ksys_write+0x12b/0x250 fs/read_write.c:731
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0ea0d847cf
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48
RSP: 002b:00007ffd32cdd4d0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007f0ea0d847cf
RDX: 0000000000000001 RSI: 00007ffd32cdd520 RDI: 0000000000000005
RBP: 00007f0ea0e02c2d R08: 0000000000000000 R09: 00007ffd32cdd327
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001
R13: 00007ffd32cdd520 R14: 00007f0ea1aa4620 R15: 0000000000000003
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5819 Comm: kworker/u9:2 Not tainted 6.13.0-rc2-syzkaller-00362-g2d8308bf5b67 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024
Workqueue: hci1 hci_cmd_timeout
RIP: 0010:mark_lock+0x1/0xc60 kernel/locking/lockdep.c:4710
Code: e8 34 5b 86 00 e9 db fe ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 <48> 89 e5 41 57 41 56 41 89 d6 48 ba 00 00 00 00 00 fc ff df 41 55
RSP: 0018:ffffc90000007ae0 EFLAGS: 00000002
RAX: 000000000000000c RBX: ffff88805fc48bca RCX: 1ffffffff2dc9e28
RDX: 0000000000000008 RSI: ffff88805fc48ba8 RDI: ffff88805fc48000
RBP: 0000000000000040 R08: 0000000000000000 R09: fffffbfff2dc9d98
R10: ffffffff96e4ecc7 R11: 0000000000000005 R12: ffffed100bf8915b
R13: ffff88805fc48000 R14: 0000000000000002 R15: ffff88805fc48ba8
FS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2e624a CR3: 000000005af24000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 mark_usage kernel/locking/lockdep.c:4670 [inline]
 __lock_acquire+0x9f1/0x3c40 kernel/locking/lockdep.c:5180
 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
 debug_object_deactivate+0x13b/0x370 lib/debugobjects.c:873
 debug_hrtimer_deactivate kernel/time/hrtimer.c:433 [inline]
 debug_deactivate kernel/time/hrtimer.c:475 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1707 [inline]
 __hrtimer_run_queues+0x47c/0xae0 kernel/time/hrtimer.c:1803
 hrtimer_interrupt+0x392/0x8e0 kernel/time/hrtimer.c:1865
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x10f/0x400 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:console_flush_all+0x9a4/0xc60 kernel/printk/printk.c:3211
Code: 00 e8 d0 15 28 00 9c 5b 81 e3 00 02 00 00 31 ff 48 89 de e8 8e 66 20 00 48 85 db 0f 85 55 01 00 00 e8 10 64 20 00 fb 4c 89 e0 <48> c1 e8 03 42 80 3c 38 00 0f 84 11 ff ff ff 4c 89 e7 e8 45 12 83
RSP: 0018:ffffc90003617840 EFLAGS: 00000293
RAX: ffffffff8ee92df8 RBX: 0000000000000000 RCX: ffffffff81799f62
RDX: ffff88805fc48000 RSI: ffffffff81799f70 RDI: 0000000000000007
RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000005 R12: ffffffff8ee92df8
R13: ffffffff8ee92da0 R14: ffffc900036178d0 R15: dffffc0000000000
 __console_flush_and_unlock kernel/printk/printk.c:3269 [inline]
 console_unlock+0xd9/0x210 kernel/printk/printk.c:3309
 vprintk_emit+0x424/0x6f0 kernel/printk/printk.c:2432
 vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:86
 _printk+0xc8/0x100 kernel/printk/printk.c:2457
 bt_err+0xe5/0x120 net/bluetooth/lib.c:296
 hci_cmd_timeout+0x1ff/0x260 net/bluetooth/hci_core.c:1456
 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229
 process_scheduled_works kernel/workqueue.c:3310 [inline]
 worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/16 00:22 upstream 2d8308bf5b67 7cbfbb3a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in hci_cmd_timeout
* Struck through repros no longer work on HEAD.