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INFO: rcu detected stall in lo_ioctl

Status: upstream: reported on 2024/06/03 22:21
Reported-by: syzbot+4365362007797bbf01ad@syzkaller.appspotmail.com
First crash: 15d, last: 15d
▶ ▼ Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in lo_ioctl (4) block 2 320d 376d 0/27 auto-obsoleted due to no activity on 2023/11/02 10:53
upstream INFO: rcu detected stall in lo_ioctl (2) kernel 2 1660d 1660d 0/27 closed as invalid on 2019/12/04 14:04
upstream INFO: rcu detected stall in lo_ioctl (3) kernfs 2 904d 908d 0/27 closed as invalid on 2022/02/08 10:00
upstream INFO: rcu detected stall in lo_ioctl block 193 2175d 2375d 0/27 closed as dup on 2018/05/04 17:09
android-5-15 BUG: soft lockup in lo_ioctl 2 30d 52d 0/2 premoderation: reported on 2024/04/28 17:42

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=f39/1/0x4000000000000000 softirq=9617/9618 fqs=16 
	(detected by 0, t=10502 jiffies, g=10205, q=154)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4345 Comm: syz-executor.3 Not tainted 5.15.160-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:91 [inline]
RIP: 0010:lock_acquire+0x119/0x4f0 kernel/locking/lockdep.c:5599
Code: 03 42 0f b6 04 28 84 c0 0f 85 dd 02 00 00 83 3d 60 ed 81 0c 00 0f 84 3f 01 00 00 65 8b 05 4f cc 9f 7e 85 c0 0f 85 88 01 00 00 <65> 48 8b 1d ff c2 9f 7e 48 81 c3 ec 0a 00 00 48 89 d8 48 c1 e8 03
RSP: 0018:ffffc90000dd0ae0 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff8162ac6c
RDX: 0000000000000000 RSI: ffffffff8ad8f6a0 RDI: ffffffff8ad8f660
RBP: ffffc90000dd0c28 R08: dffffc0000000000 R09: fffffbfff1bc8cce
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920001ba164
R13: dffffc0000000000 R14: 0000000000000000 R15: dffffc0000000000
FS:  00007f9a6c4096c0(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000200cb030 CR3: 00000000622f9000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
 debug_object_deactivate+0x63/0x380 lib/debugobjects.c:748
 debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline]
 debug_deactivate+0x1b/0x1e0 kernel/time/hrtimer.c:481
 __run_hrtimer kernel/time/hrtimer.c:1654 [inline]
 __hrtimer_run_queues+0x31d/0xcf0 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:console_unlock+0xe53/0x12b0 kernel/printk/printk.c:2749
Code: 00 48 83 7c 24 18 00 75 19 e8 79 03 1a 00 eb 18 e8 72 03 1a 00 e8 5d 94 b7 08 48 83 7c 24 18 00 74 e7 e8 60 03 1a 00 fb 31 ff <44> 89 f6 e8 b5 06 1a 00 31 db 45 85 f6 0f 95 c0 89 c1 0a 4c 24 17
RSP: 0018:ffffc90003076dc0 EFLAGS: 00000246
RAX: ffffffff81665960 RBX: 0000000000000000 RCX: 0000000000040000
RDX: ffffc90006213000 RSI: 000000000003ffff RDI: 0000000000000000
RBP: ffffc90003077050 R08: ffffffff8166592b R09: fffffbfff1f7f019
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffffffff1a4b1da
R13: ffffffff8d258f08 R14: 0000000000000000 R15: dffffc0000000000
 vprintk_emit+0xbf/0x150 kernel/printk/printk.c:2274
 _printk+0xd1/0x120 kernel/printk/printk.c:2299
 disk_unlock_native_capacity block/partitions/core.c:536 [inline]
 blk_add_partition block/partitions/core.c:580 [inline]
 blk_add_partitions block/partitions/core.c:658 [inline]
 bdev_disk_changed+0x1033/0x16c0 block/partitions/core.c:700
 loop_reread_partitions drivers/block/loop.c:681 [inline]
 loop_set_status+0x6b2/0x8e0 drivers/block/loop.c:1589
 lo_ioctl+0xea1/0x23b0
 blkdev_ioctl+0x333/0x6b0 block/ioctl.c:604
 block_ioctl+0xb1/0xf0 block/fops.c:493
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f9a6d88fccb
Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00
RSP: 002b:00007f9a6c408df0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f9a6c408e80 RCX: 00007f9a6d88fccb
RDX: 00007f9a6c408f90 RSI: 0000000000004c04 RDI: 0000000000000004
RBP: 0000000000000004 R08: 0000000000000000 R09: 000000000000105c
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f9a6c408f90
R13: 000000000000000b R14: 00007f9a6d9c6fa0 R15: 00007ffecb9b64f8
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10469 jiffies! g10205 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=4090
rcu: rcu_preempt kthread starved for 10470 jiffies! g10205 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
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:I stack:27000 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1f0 kernel/sched/core.c:6459
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 144 Comm: kworker/u4:1 Not tainted 5.15.160-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Workqueue: netns cleanup_net
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3932 [inline]
 rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619
 update_process_times+0x196/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1686 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:check_kcov_mode kernel/kcov.c:174 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x32/0x60 kernel/kcov.c:197
Code: f4 12 82 7e 65 8b 15 f5 12 82 7e f7 c2 00 01 ff 00 74 11 f7 c2 00 01 00 00 74 35 83 b9 34 16 00 00 00 74 2c 8b 91 10 16 00 00 <83> fa 02 75 21 48 8b 91 18 16 00 00 48 8b 32 48 8d 7e 01 8b 89 14
RSP: 0018:ffffc900016cf9b8 EFLAGS: 00000246
RAX: ffffffff81747bbe RBX: 1ffff920002d9f41 RCX: ffff888016cdbb80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900016cfab0 R08: ffffffff81747b90 R09: ffffed1017367681
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 0000000000000001 R14: ffffc900016cfa08 R15: 0000000000000000
 csd_lock_wait kernel/smp.c:440 [inline]
 smp_call_function_single+0x2ae/0x530 kernel/smp.c:758
 rcu_barrier+0x262/0x4e0 kernel/rcu/tree.c:4078
 cleanup_net+0x81c/0xb60 net/core/net_namespace.c:610
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300
 </TASK>
watchdog: BUG: soft lockup - CPU#0 stuck for 246s! [kworker/u4:1:144]
Modules linked in:
irq event stamp: 1390054
hardirqs last  enabled at (1390053): [<ffffffff8a400d06>] asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
hardirqs last disabled at (1390054): [<ffffffff8a1de12a>] sysvec_apic_timer_interrupt+0xa/0xb0 arch/x86/kernel/apic/apic.c:1096
softirqs last  enabled at (1340666): [<ffffffff814d84f5>] invoke_softirq kernel/softirq.c:432 [inline]
softirqs last  enabled at (1340666): [<ffffffff814d84f5>] __irq_exit_rcu+0x155/0x240 kernel/softirq.c:637
softirqs last disabled at (1340583): [<ffffffff814d84f5>] invoke_softirq kernel/softirq.c:432 [inline]
softirqs last disabled at (1340583): [<ffffffff814d84f5>] __irq_exit_rcu+0x155/0x240 kernel/softirq.c:637
CPU: 0 PID: 144 Comm: kworker/u4:1 Not tainted 5.15.160-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Workqueue: netns cleanup_net
RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline]
RIP: 0010:smp_call_function_single+0x292/0x530 kernel/smp.c:758
Code: 0f 85 24 02 00 00 44 8b 6c 24 48 44 89 ee 83 e6 01 31 ff e8 90 e4 0b 00 41 83 e5 01 75 0a e8 25 e1 0b 00 e9 eb 00 00 00 f3 90 <42> 0f b6 04 23 84 c0 75 15 f7 44 24 48 01 00 00 00 0f 84 cd 00 00
RSP: 0018:ffffc900016cf9c0 EFLAGS: 00000293
RAX: ffffffff81747bbe RBX: 1ffff920002d9f41 RCX: ffff888016cdbb80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900016cfab0 R08: ffffffff81747b90 R09: ffffed1017367681
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 0000000000000001 R14: ffffc900016cfa08 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020178030 CR3: 0000000063b3e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 rcu_barrier+0x262/0x4e0 kernel/rcu/tree.c:4078
 cleanup_net+0x81c/0xb60 net/core/net_namespace.c:610
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4345 Comm: syz-executor.3 Not tainted 5.15.160-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
RIP: 0010:cpu_max_bits_warn include/linux/cpumask.h:108 [inline]
RIP: 0010:cpumask_check include/linux/cpumask.h:115 [inline]
RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:344 [inline]
RIP: 0010:cpu_online include/linux/cpumask.h:895 [inline]
RIP: 0010:trace_lock_release include/trace/events/lock.h:58 [inline]
RIP: 0010:lock_release+0x88/0x9a0 kernel/locking/lockdep.c:5634
Code: 03 48 b8 f1 f1 f1 f1 04 f2 00 f2 4b 89 04 3c 48 b8 f2 f2 00 f3 f3 f3 f3 f3 4b 89 44 3c 08 0f 1f 44 00 00 65 8b 1d 10 43 9f 7e <83> fb 08 0f 83 d3 05 00 00 89 d8 c1 e8 06 48 8d 3c c5 68 66 e4 8d
RSP: 0018:ffffc90000dd0b60 EFLAGS: 00000806
RAX: f3f3f3f3f300f2f2 RBX: 0000000000000001 RCX: 0000000000000002
RDX: dffffc0000000000 RSI: ffffffff816f93bb RDI: ffffffff915eebd0
RBP: ffffc90000dd0c90 R08: dffffc0000000000 R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: 1ffff920001ba178
R13: ffffffff816f93bb R14: ffffc90000dd0cc0 R15: dffffc0000000000
FS:  00007f9a6c4096c0(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000200cb030 CR3: 00000000622f9000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:158 [inline]
 _raw_spin_unlock_irqrestore+0x75/0x130 kernel/locking/spinlock.c:194
 debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline]
 debug_deactivate+0x1b/0x1e0 kernel/time/hrtimer.c:481
 __run_hrtimer kernel/time/hrtimer.c:1654 [inline]
 __hrtimer_run_queues+0x31d/0xcf0 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:console_unlock+0xe53/0x12b0 kernel/printk/printk.c:2749
Code: 00 48 83 7c 24 18 00 75 19 e8 79 03 1a 00 eb 18 e8 72 03 1a 00 e8 5d 94 b7 08 48 83 7c 24 18 00 74 e7 e8 60 03 1a 00 fb 31 ff <44> 89 f6 e8 b5 06 1a 00 31 db 45 85 f6 0f 95 c0 89 c1 0a 4c 24 17
RSP: 0018:ffffc90003076dc0 EFLAGS: 00000246
RAX: ffffffff81665960 RBX: 0000000000000000 RCX: 0000000000040000
RDX: ffffc90006213000 RSI: 000000000003ffff RDI: 0000000000000000
RBP: ffffc90003077050 R08: ffffffff8166592b R09: fffffbfff1f7f019
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffffffff1a4b1da
R13: ffffffff8d258f08 R14: 0000000000000000 R15: dffffc0000000000
 vprintk_emit+0xbf/0x150 kernel/printk/printk.c:2274
 _printk+0xd1/0x120 kernel/printk/printk.c:2299
 disk_unlock_native_capacity block/partitions/core.c:536 [inline]
 blk_add_partition block/partitions/core.c:580 [inline]
 blk_add_partitions block/partitions/core.c:658 [inline]
 bdev_disk_changed+0x1033/0x16c0 block/partitions/core.c:700
 loop_reread_partitions drivers/block/loop.c:681 [inline]
 loop_set_status+0x6b2/0x8e0 drivers/block/loop.c:1589
 lo_ioctl+0xea1/0x23b0
 blkdev_ioctl+0x333/0x6b0 block/ioctl.c:604
 block_ioctl+0xb1/0xf0 block/fops.c:493
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f9a6d88fccb
Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00
RSP: 002b:00007f9a6c408df0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f9a6c408e80 RCX: 00007f9a6d88fccb
RDX: 00007f9a6c408f90 RSI: 0000000000004c04 RDI: 0000000000000004
RBP: 0000000000000004 R08: 0000000000000000 R09: 000000000000105c
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f9a6c408f90
R13: 000000000000000b R14: 00007f9a6d9c6fa0 R15: 00007ffecb9b64f8
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/03 22:20 linux-5.15.y c61bd26ae81a a1feae05 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in lo_ioctl
* Struck through repros no longer work on HEAD.