rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=a534/1/0x4000000000000000 softirq=104835/104836 fqs=14
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P20157/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=87357, q=36 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 20218 Comm: syz.5.3341 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:debug_spin_unlock kernel/locking/spinlock_debug.c:102 [inline]
RIP: 0010:do_raw_spin_unlock+0x91/0x230 kernel/locking/spinlock_debug.c:141
Code: 02 48 89 d8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 6c 01 00 00 8b 03 85 c0 0f 84 f5 00 00 00 48 b8 00 00 00 00 00 fc ff df <4c> 8d 63 10 4c 89 e2 48 c1 ea 03 80 3c 02 00 0f 85 67 01 00 00 65
RSP: 0018:ffffc90000a08d60 EFLAGS: 00000002
RAX: dffffc0000000000 RBX: ffff88806865f2a8 RCX: ffffffff819a58d3
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88806865f2a8
RBP: ffff888059889800 R08: 0000000000000000 R09: ffffed100d0cbe55
R10: ffff88806865f2ab R11: ffff888066a354b0 R12: 1891917eae0d3616
R13: 1891917eae0d3616 R14: 0000000000000002 R15: ffff88805988a410
FS: 00007f5ddaa056c0(0000) GS:ffff8881249f4000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000006680 CR3: 0000000035686000 CR4: 00000000003526f0
DR0: ffffffffffffffff DR1: 0000000000000009 DR2: 0000000000000083
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
__raw_spin_unlock include/linux/spinlock_api_smp.h:142 [inline]
_raw_spin_unlock+0x1e/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
advance_sched+0x62b/0xc80 net/sched/sch_taprio.c:987
__run_hrtimer kernel/time/hrtimer.c:1777 [inline]
__hrtimer_run_queues+0x202/0xc40 kernel/time/hrtimer.c:1841
hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1903
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
__sysvec_apic_timer_interrupt+0x10b/0x3c0 arch/x86/kernel/apic/apic.c:1062
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x62/0x330 kernel/locking/lockdep.c:5872
Code: b3 18 12 83 f8 07 0f 87 a2 02 00 00 89 c0 48 0f a3 05 52 b1 ee 0e 0f 82 74 02 00 00 8b 35 ea e1 ee 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 69 b3 18 12 0f 85 ad 02 00 00 48 83 c4
RSP: 0018:ffffc9000491fa58 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e295160 RCX: 0000000007e52c32
RDX: 0000000000000000 RSI: ffffffff8daa8a1d RDI: ffffffff8bf2b400
RBP: 0000000000000000 R08: 00000000ffffffff R09: 00000000ffffffff
R10: 0000000000000000 R11: ffff888066a354b0 R12: 0000000000000001
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000
sched_submit_work kernel/sched/core.c:6901 [inline]
schedule+0x21c/0x3a0 kernel/sched/core.c:6959
futex_do_wait+0x88/0x180 kernel/futex/waitwake.c:358
__futex_wait+0x1b8/0x2f0 kernel/futex/waitwake.c:687
futex_wait+0xe8/0x380 kernel/futex/waitwake.c:715
do_futex+0x229/0x350 kernel/futex/syscalls.c:130
__do_sys_futex kernel/futex/syscalls.c:207 [inline]
__se_sys_futex kernel/futex/syscalls.c:188 [inline]
__x64_sys_futex+0x1e0/0x4c0 kernel/futex/syscalls.c:188
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5dd9b8f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f5ddaa050e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f5dd9de5fa8 RCX: 00007f5dd9b8f749
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f5dd9de5fa8
RBP: 00007f5dd9de5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5dd9de6038 R14: 00007ffcc933e6a0 R15: 00007ffcc933e788
task:syz-executor state:R running task stack:24008 pid:20157 tgid:20157 ppid:20145 task_flags:0x480140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_release+0x183/0x2d0 kernel/locking/lockdep.c:5893
Code: 0f c1 05 28 00 19 12 83 f8 01 0f 85 03 01 00 00 9c 58 f6 c4 02 0f 85 ee 00 00 00 41 f7 c5 00 02 00 00 74 01 fb 48 8b 44 24 10 <65> 48 2b 05 bd b8 18 12 0f 85 32 01 00 00 48 83 c4 18 5b 41 5c 41
RSP: 0018:ffffc9000cf1f148 EFLAGS: 00000206
RAX: b4db81554d16d700 RBX: ffffffff8e3c96a0 RCX: ffffc9000cf1f154
RDX: 0000000000000008 RSI: ffffffff8daa8a1d RDI: ffffffff8bf2b400
RBP: 0000000000000001 R08: 0000000000000001 R09: 00000000a609d288
R10: 0000000000000002 R11: 0000000000016bbd R12: ffffffff816cca34
R13: 0000000000000206 R14: ffff88801f3e8000 R15: 0000000000000009
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:897 [inline]
class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0x3f9/0x20b0 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x33/0x60 mm/kasan/common.c:57
kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556
__call_rcu_common.constprop.0+0xa5/0xa10 kernel/rcu/tree.c:3119
kernfs_put.part.0+0x162/0x600 fs/kernfs/dir.c:591
kernfs_put fs/kernfs/dir.c:1729 [inline]
kernfs_remove_by_name_ns+0xdf/0x100 fs/kernfs/dir.c:1723
kernfs_remove_by_name include/linux/kernfs.h:633 [inline]
remove_files+0x96/0x1c0 fs/sysfs/group.c:28
sysfs_remove_group+0x8b/0x1b0 fs/sysfs/group.c:328
netdev_queue_update_kobjects+0x4b2/0x710 net/core/net-sysfs.c:2070
remove_queue_kobjects net/core/net-sysfs.c:2170 [inline]
netdev_unregister_kobject+0x168/0x540 net/core/net-sysfs.c:2325
unregister_netdevice_many_notify+0x151e/0x2590 net/core/dev.c:12418
unregister_netdevice_many net/core/dev.c:12446 [inline]
unregister_netdevice_queue net/core/dev.c:12260 [inline]
unregister_netdevice_queue+0x305/0x3c0 net/core/dev.c:12250
unregister_netdevice include/linux/netdevice.h:3405 [inline]
nsim_destroy+0x1a0/0x830 drivers/net/netdevsim/netdev.c:1180
__nsim_dev_port_del+0x189/0x240 drivers/net/netdevsim/dev.c:1528
nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1540 [inline]
nsim_dev_reload_destroy+0x10a/0x4d0 drivers/net/netdevsim/dev.c:1763
nsim_drv_remove+0x52/0x1d0 drivers/net/netdevsim/dev.c:1778
device_remove+0xcb/0x170 drivers/base/dd.c:569
__device_release_driver drivers/base/dd.c:1282 [inline]
device_release_driver_internal+0x44b/0x620 drivers/base/dd.c:1305
bus_remove_device+0x22f/0x450 drivers/base/bus.c:616
device_del+0x396/0x9f0 drivers/base/core.c:3878
device_unregister+0x1d/0xe0 drivers/base/core.c:3919
nsim_bus_dev_del drivers/net/netdevsim/bus.c:491 [inline]
del_device_store+0x355/0x4a0 drivers/net/netdevsim/bus.c:244
bus_attr_store+0x74/0xb0 drivers/base/bus.c:172
sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:142
kernfs_fop_write_iter+0x3af/0x570 fs/kernfs/file.c:352
new_sync_write fs/read_write.c:593 [inline]
vfs_write+0x7d3/0x11d0 fs/read_write.c:686
ksys_write+0x12a/0x250 fs/read_write.c:738
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f93cbb8e1ff
RSP: 002b:00007ffe00636630 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007f93cbb8e1ff
RDX: 0000000000000001 RSI: 00007ffe00636680 RDI: 0000000000000005
RBP: 00007f93cbc152cb R08: 0000000000000000 R09: 00007ffe00636487
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001
R13: 00007ffe00636680 R14: 00007f93cc914620 R15: 0000000000000003
rcu: rcu_preempt kthread starved for 10474 jiffies! g87357 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:28728 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 20220 Comm: syz.5.3341 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xe02/0x15e0 kernel/smp.c:877
Code: 10 4c 89 74 24 10 49 89 d5 48 89 d5 48 89 54 24 18 49 c1 ed 03 83 e5 07 4d 01 e5 83 c5 03 e8 45 5f 0c 00 f3 90 41 0f b6 45 00 <40> 38 c5 7c 08 84 c0 0f 85 b6 05 00 00 8b 43 08 31 ff 83 e0 01 41
RSP: 0018:ffffc900049af370 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff8880b8540cc0 RCX: ffffc90026410000
RDX: 0000000000080000 RSI: ffffffff81b29c8b RDI: 0000000000000005
RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: ffff88807b000b30 R12: dffffc0000000000
R13: ffffed10170a8199 R14: 0000000000000001 R15: 0000000000000001
FS: 00007f5dda9c36c0(0000) GS:ffff8881248f4000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000035686000 CR4: 00000000003526f0
DR0: ffffffffffffffff DR1: 0000000000000009 DR2: 0000000000000083
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1043
__flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1382 [inline]
flush_tlb_mm_range+0x2f0/0x12c0 arch/x86/mm/tlb.c:1472
tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:490 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:480 [inline]
tlb_flush_mmu mm/mmu_gather.c:403 [inline]
tlb_finish_mmu+0x3c9/0x7c0 mm/mmu_gather.c:497
vms_clear_ptes+0x55a/0x790 mm/vma.c:1238
vms_clean_up_area mm/vma.c:1250 [inline]
__mmap_setup mm/vma.c:2403 [inline]
__mmap_region+0x627/0x2a00 mm/vma.c:2690
mmap_region+0x1ab/0x3f0 mm/vma.c:2786
do_mmap+0xa3e/0x1210 mm/mmap.c:558
vm_mmap_pgoff+0x29e/0x470 mm/util.c:581
ksys_mmap_pgoff+0x7d/0x5c0 mm/mmap.c:604
__do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline]
__se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline]
__x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5dd9b8f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f5dda9c3038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f5dd9de6180 RCX: 00007f5dd9b8f749
RDX: 000000000000000f RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007f5dd9c13f91 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000004008032 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5dd9de6218 R14: 00007f5dd9de6180 R15: 00007ffcc933e788