rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P8539/1:b..l
rcu: (detected by 0, t=10504 jiffies, g=18917, q=79 ncpus=2)
task:syz.3.542 state:R running task stack:27016 pid:8539 tgid:8536 ppid:5818 task_flags:0x40044c flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x116f/0x5de0 kernel/sched/core.c:6767
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7090
irqentry_exit+0x36/0x90 kernel/entry/common.c:354
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_release+0x183/0x2f0 kernel/locking/lockdep.c:5891
Code: 0f c1 05 68 21 0c 12 83 f8 01 0f 85 1d 01 00 00 9c 58 f6 c4 02 0f 85 08 01 00 00 41 f7 c5 00 02 00 00 74 01 fb 48 8b 44 24 10 <65> 48 2b 05 bd e3 0b 12 0f 85 58 01 00 00 48 83 c4 18 5b 41 5c 41
RSP: 0018:ffffc9000cf3ef58 EFLAGS: 00000206
RAX: 1178d54afb1bd100 RBX: ffffffff8e3bf580 RCX: ffffc9000cf3ef64
RDX: 0000000000000000 RSI: ffffffff8dbbc38a RDI: ffffffff8bf483a0
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 000000000000fde5 R12: ffffffff8169cd14
R13: 0000000000000206 R14: ffff888063e02440 R15: 0000000000000001
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:871 [inline]
class_rcu_destructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0x3f9/0x20a0 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
save_stack+0x160/0x1f0 mm/page_owner.c:156
__reset_page_owner+0x84/0x1a0 mm/page_owner.c:308
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1262 [inline]
free_unref_folios+0x999/0x1630 mm/page_alloc.c:2782
folios_put_refs+0x56f/0x740 mm/swap.c:992
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x58f/0x1150 mm/shmem.c:1125
shmem_truncate_range mm/shmem.c:1237 [inline]
shmem_evict_inode+0x3a1/0xbe0 mm/shmem.c:1365
evict+0x3e3/0x920 fs/inode.c:810
iput_final fs/inode.c:1898 [inline]
iput fs/inode.c:1924 [inline]
iput+0x521/0x880 fs/inode.c:1910
dentry_unlink_inode+0x29c/0x480 fs/dcache.c:457
__dentry_kill+0x1d0/0x600 fs/dcache.c:660
dput.part.0+0x4b1/0x9b0 fs/dcache.c:902
dput+0x1f/0x30 fs/dcache.c:892
__fput+0x51c/0xb70 fs/file_table.c:473
task_work_run+0x14d/0x240 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0xafb/0x2c30 kernel/exit.c:953
do_group_exit+0xd3/0x2a0 kernel/exit.c:1102
get_signal+0x2673/0x26d0 kernel/signal.c:3034
arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x260 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3cc118e969
RSP: 002b:00007f3cc1fb20e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f3cc13b6088 RCX: 00007f3cc118e969
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f3cc13b6088
RBP: 00007f3cc13b6080 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3cc13b608c
R13: 0000000000000000 R14: 00007ffcc4417f90 R15: 00007ffcc4418078
rcu: rcu_preempt kthread starved for 10496 jiffies! g18917 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:28456 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x116f/0x5de0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6860
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2046
rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2248
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 8558 Comm: syz.4.547 Not tainted 6.15.0-rc6-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0x4a5/0x1290 kernel/smp.c:885
Code: 89 ee e8 be 12 0c 00 85 ed 74 48 48 8b 44 24 20 49 89 c4 83 e0 07 49 c1 ec 03 48 89 c5 4d 01 f4 83 c5 03 e8 5d 17 0c 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 de 0b 00 00 8b 43 08 31
RSP: 0018:ffffc9000cc1f8b8 EFLAGS: 00000246
RAX: 0000000000080000 RBX: ffff8880b853f740 RCX: ffffc9000f872000
RDX: 0000000000080000 RSI: ffffffff81af1973 RDI: 0000000000000005
RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffed10170a7ee9
R13: 0000000000000001 R14: dffffc0000000000 R15: ffff8880b843b040
FS: 00007f853fdf66c0(0000) GS:ffff8881249e1000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f853fdf5f98 CR3: 0000000063338000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1052
__flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1291 [inline]
flush_tlb_mm_range+0x322/0x1780 arch/x86/mm/tlb.c:1381
dup_mmap kernel/fork.c:765 [inline]
dup_mm kernel/fork.c:1734 [inline]
copy_mm kernel/fork.c:1786 [inline]
copy_process+0x7961/0x91a0 kernel/fork.c:2429
kernel_clone+0xfc/0x960 kernel/fork.c:2844
__do_sys_clone+0xce/0x120 kernel/fork.c:2987
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8541f8e969
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:00007f853fdf5fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007f85421b6160 RCX: 00007f8541f8e969
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000900a000
RBP: 00007f8542010ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f85421b6160 R15: 00007fffe7317258