rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=b2a4/1/0x4000000000000000 softirq=174486/174493 fqs=4
rcu: (detected by 1, t=10502 jiffies, g=136873, q=1172 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 24980 Comm: syz.1.5104 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:__lock_is_held kernel/locking/lockdep.c:5601 [inline]
RIP: 0010:lock_is_held_type+0x8b/0x150 kernel/locking/lockdep.c:5940
Code: 41 83 bd 88 0b 00 00 00 7e 48 4c 89 eb 48 81 c3 90 0b 00 00 45 31 ff 49 83 ff 31 73 24 48 89 df 4c 89 f6 e8 f7 01 00 00 85 c0 <75> 2a 49 ff c7 49 63 85 88 0b 00 00 48 83 c3 28 49 39 c7 7c d8 eb
RSP: 0018:ffffc90000007cd8 EFLAGS: 00000002
RAX: 0000000000000001 RBX: ffff88807925aa50 RCX: 0000000000010001
RDX: ffff888079259ec0 RSI: ffff88807dabc2c0 RDI: ffff88807925aa50
RBP: 00000000ffffffff R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000000f90 R12: 0000000000000046
R13: ffff888079259ec0 R14: ffff88807dabc2c0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125290000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3031aff8 CR3: 000000000e74a000 CR4: 0000000000350ef0
Call Trace:
lock_is_held include/linux/lockdep.h:249 [inline]
advance_sched+0x14c/0xc20 net/sched/sch_taprio.c:933
__run_hrtimer kernel/time/hrtimer.c:1930 [inline]
__hrtimer_run_queues+0x3c0/0xa20 kernel/time/hrtimer.c:1994
hrtimer_interrupt+0x44b/0x950 kernel/time/hrtimer.c:2113
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
__sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1067
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1061
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:const_folio_flags include/linux/page-flags.h:345 [inline]
RIP: 0010:folio_test_swapbacked include/linux/page-flags.h:572 [inline]
RIP: 0010:folio_test_swapcache include/linux/page-flags.h:627 [inline]
RIP: 0010:folio_mapping+0x83/0x1f0 mm/util.c:729
Code: 8d 73 08 4d 89 f4 49 c1 ec 03 43 80 3c 3c 00 74 08 4c 89 f7 e8 8e b0 21 00 4d 8b 2e 4c 89 ee 48 83 e6 01 31 ff e8 ed 79 b6 ff <49> 83 e5 01 0f 85 2a 01 00 00 48 89 df be 08 00 00 00 e8 d6 b2 21
RSP: 0018:ffffc9000649f458 EFLAGS: 00000293
RAX: ffffffff820f4733 RBX: ffffea0001325680 RCX: ffff888079259ec0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00000000ff000000 R08: ffffea00013256b3 R09: 1ffffd4000264ad6
R10: dffffc0000000000 R11: fffff94000264ad7 R12: 1ffffd4000264ad1
R13: ffffea0001325648 R14: ffffea0001325688 R15: dffffc0000000000
folio_needs_release+0x1f/0xc0 mm/internal.h:614
truncate_cleanup_folio+0x43/0x190 mm/truncate.c:159
truncate_inode_folio+0x55/0x70 mm/truncate.c:175
shmem_undo_range+0x42f/0x1660 mm/shmem.c:1145
shmem_truncate_range mm/shmem.c:1277 [inline]
shmem_evict_inode+0x289/0xae0 mm/shmem.c:1407
evict+0x61e/0xb10 fs/inode.c:841
__dentry_kill+0x1a2/0x690 fs/dcache.c:718
finish_dput+0xc9/0x480 fs/dcache.c:927
__fput+0x691/0xa60 fs/file_table.c:518
task_work_run+0x1d9/0x270 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x70f/0x22c0 kernel/exit.c:975
do_group_exit+0x21b/0x2d0 kernel/exit.c:1117
__do_sys_exit_group kernel/exit.c:1128 [inline]
__se_sys_exit_group kernel/exit.c:1126 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1126
x64_sys_call+0x221a/0x2240 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9e4fd9cdd9
Code: Unable to access opcode bytes at 0x7f9e4fd9cdaf.
RSP: 002b:00007ffe1f8bc838 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f9e4fd9cdd9
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffe1f8bc89c R08: 0000000000000000 R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 000000000000009e
R13: 00000000000927c0 R14: 00000000000f2386 R15: 00007ffe1f8bc8f0
rcu: rcu_preempt kthread starved for 10494 jiffies! g136873 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:27544 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x17b4/0x5680 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7283
schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
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: 25011 Comm: syz.7.5112 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xfd4/0x13d0 kernel/smp.c:892
Code: 89 ee 83 e6 01 31 ff e8 7a 05 0c 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 25 01 0c 00 eb 37 f3 90 43 0f b6 04 2c <84> c0 75 10 41 f7 06 01 00 00 00 74 1e e8 0a 01 0c 00 eb e5 44 89
RSP: 0018:ffffc9000686f580 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b873c148 RCX: ffff88802eccbd80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000686f6c0 R08: ffff8880342aa407 R09: 1ffff11006855480
R10: dffffc0000000000 R11: ffffed1006855481 R12: 1ffff110170c8589
R13: dffffc0000000000 R14: ffff8880b8642c48 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125390000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0190d456b8 CR3: 000000008257a000 CR4: 0000000000350ef0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1057
__flush_tlb_multi arch/x86/include/asm/paravirt.h:46 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
flush_tlb_mm_range+0x5c3/0x10b0 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:509 [inline]
tlb_flush_mmu+0x1af/0xa30 mm/mmu_gather.c:423
tlb_finish_mmu+0xf9/0x230 mm/mmu_gather.c:549
exit_mmap+0x498/0x9e0 mm/mmap.c:1313
__mmput+0x118/0x430 kernel/fork.c:1178
exit_mm+0x18e/0x250 kernel/exit.c:581
do_exit+0x6a2/0x22c0 kernel/exit.c:963
do_group_exit+0x21b/0x2d0 kernel/exit.c:1117
get_signal+0x1284/0x1330 kernel/signal.c:3037
arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe70639cdd9
Code: Unable to access opcode bytes at 0x7fe70639cdaf.
RSP: 002b:00007fe7071860e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 00007fe706615fa8 RCX: 00007fe70639cdd9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fe706615fac
RBP: 00007fe706615fa0 R08: 3fffffffffffffff R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe706616038 R14: 00007ffed5ecb990 R15: 00007ffed5ecba78