rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=2e44/1/0x4000000000000000 softirq=113612/113613 fqs=2
rcu: (detected by 1, t=10505 jiffies, g=86201, q=160 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 16883 Comm: syz.2.2156 Not tainted 6.16.0-next-20250808-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4896 [inline]
RIP: 0010:__lock_acquire+0x581/0xd20 kernel/locking/lockdep.c:5187
Code: 90 31 c9 48 8b 3c 24 0f b6 81 c4 00 00 00 84 c0 0f 84 68 ff ff ff 41 0f b6 f4 0f b6 d0 40 38 c6 0f 42 d6 80 b9 c6 00 00 00 02 <0f> 84 51 ff ff ff 89 d0 e9 4a ff ff ff 48 c7 c7 d0 ae 00 8e 48 89
RSP: 0018:ffffc90000007ab0 EFLAGS: 00000093
RAX: 0000000000000002 RBX: 0000000000000000 RCX: ffffffff9349c838
RDX: 0000000000000002 RSI: 0000000000000002 RDI: ffff88805001da00
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff84d19b4b
R10: ffffc90000007ca0 R11: fffff52000000f96 R12: ffffffffffffff02
R13: 0000000000000002 R14: ffff88805001e518 R15: ffff88805001e510
FS: 0000000000000000(0000) GS:ffff888125c15000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000040000 CR3: 000000000df36000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
debug_object_activate+0xbb/0x420 lib/debugobjects.c:818
debug_hrtimer_activate kernel/time/hrtimer.c:445 [inline]
debug_activate kernel/time/hrtimer.c:484 [inline]
enqueue_hrtimer+0x30/0x3a0 kernel/time/hrtimer.c:1088
__run_hrtimer kernel/time/hrtimer.c:1778 [inline]
__hrtimer_run_queues+0x656/0xc60 kernel/time/hrtimer.c:1825
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
__sysvec_apic_timer_interrupt+0x108/0x410 arch/x86/kernel/apic/apic.c:1056
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xa8/0x110 kernel/locking/spinlock.c:194
Code: 74 05 e8 8b dd 49 f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 73 7e 12 f6 65 8b 05 9c 30 23 07 85 c0 74 40 48 c7 04 24 0e 36
RSP: 0018:ffffc9000c127120 EFLAGS: 00000206
RAX: 458a15612577a200 RBX: 0000000000000a02 RCX: 458a15612577a200
RDX: 0000000000000000 RSI: ffffffff8d9b8efe RDI: 0000000000000001
RBP: ffffc9000c1271b0 R08: ffffffff8fa39a37 R09: 1ffffffff1f47346
R10: dffffc0000000000 R11: fffffbfff1f47347 R12: dffffc0000000000
R13: ffffc9000c127478 R14: ffff88801b6fa198 R15: 1ffff92001824e24
spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
unlock_page_lruvec_irqrestore include/linux/memcontrol.h:1508 [inline]
folios_put_refs+0x4ef/0x640 mm/swap.c:989
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x49e/0x14b0 mm/shmem.c:1157
shmem_truncate_range mm/shmem.c:1269 [inline]
shmem_evict_inode+0x272/0xa70 mm/shmem.c:1397
evict+0x501/0x9c0 fs/inode.c:810
__dentry_kill+0x209/0x660 fs/dcache.c:669
dput+0x19f/0x2b0 fs/dcache.c:911
__fput+0x68e/0xa70 fs/file_table.c:476
task_work_run+0x1d1/0x260 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x6b5/0x2300 kernel/exit.c:961
do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
get_signal+0x1286/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa9ca58ebe9
Code: Unable to access opcode bytes at 0x7fa9ca58ebbf.
RSP: 002b:00007fa9cb3e4038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: fffffffffffffe00 RBX: 00007fa9ca7b5fa0 RCX: 00007fa9ca58ebe9
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000008
RBP: 00007fa9ca611e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa9ca7b6038 R14: 00007fa9ca7b5fa0 R15: 00007ffeeb8beff8
rcu: rcu_preempt kthread starved for 10495 jiffies! g86201 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:25760 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 16874 Comm: syz.8.2154 Not tainted 6.16.0-next-20250808-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xd3c/0x12d0 kernel/smp.c:877
Code: 01 31 ff e8 b6 62 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 61 5e 0b 00 eb 38 f3 90 42 0f b6 04 2b 84 c0 75 11 <41> f7 04 24 01 00 00 00 74 1e e8 45 5e 0b 00 eb e4 44 89 e1 80 e1
RSP: 0018:ffffc9000c187340 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 1ffff110170c8341 RCX: ffff888020389e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000c1874c0 R08: ffffffff8fa39a37 R09: 1ffffffff1f47346
R10: dffffc0000000000 R11: fffffbfff1f47347 R12: ffff8880b8641a08
R13: dffffc0000000000 R14: ffff8880b873b1c0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125d15000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3ed69d4f98 CR3: 000000000df36000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1044
__flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
flush_tlb_mm_range+0x6b1/0x12d0 arch/x86/mm/tlb.c:1451
tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:490 [inline]
tlb_flush_mmu+0x1a7/0x680 mm/mmu_gather.c:403
tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497
free_ldt_pgtables+0x17b/0x320 arch/x86/kernel/ldt.c:411
arch_exit_mmap arch/x86/include/asm/mmu_context.h:234 [inline]
exit_mmap+0x17c/0xb50 mm/mmap.c:1266
__mmput+0x118/0x420 kernel/fork.c:1130
exit_mm+0x1da/0x2c0 kernel/exit.c:582
do_exit+0x648/0x2300 kernel/exit.c:949
do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
get_signal+0x1286/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f637eb8ebe9
Code: Unable to access opcode bytes at 0x7f637eb8ebbf.
RSP: 002b:00007f637f9120e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f637edb5fa8 RCX: 00007f637eb8ebe9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f637edb5fa8
RBP: 00007f637edb5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f637edb6038 R14: 00007ffd2aa67820 R15: 00007ffd2aa67908