rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P21498/1:b..l
rcu: (detected by 1, t=10503 jiffies, g=113321, q=2664 ncpus=2)
task:syz.2.3876 state:R running task stack:23592 pid:21498 tgid:21498 ppid:18654 task_flags:0x40064c flags:0x00080001
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_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:rcu_preempt_read_exit kernel/rcu/tree_plugin.h:396 [inline]
RIP: 0010:__rcu_read_unlock+0x31/0x5a0 kernel/rcu/tree_plugin.h:435
Code: 54 55 65 48 8b 2d e7 6f 0e 12 53 48 8d bd 84 04 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 <83> e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 45 02 00 00 65 4c 8b 25
RSP: 0018:ffffc9000e2def10 EFLAGS: 00000a07
RAX: ffff88805f4bce04 RBX: ffffc9000e2dfa80 RCX: ffffc9000e2deefc
RDX: 0000000000000000 RSI: ffffffff8daa7ea1 RDI: ffff88805f4bce04
RBP: ffff88805f4bc980 R08: 0000000000000001 R09: 00000000ffffffff
R10: 0000000000000002 R11: 000000000001434f R12: ffffc9000e2deff8
R13: ffffc9000e2defa8 R14: ffffc9000e2dfa80 R15: ffffc9000e2defdc
rcu_read_unlock include/linux/rcupdate.h:899 [inline]
class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0x3fe/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
save_stack+0x160/0x1f0 mm/page_owner.c:165
__reset_page_owner+0x84/0x1a0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1395 [inline]
free_unref_folios+0xa22/0x1610 mm/page_alloc.c:3000
folios_put_refs+0x4be/0x750 mm/swap.c:1002
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x58f/0x1140 mm/shmem.c:1137
shmem_truncate_range mm/shmem.c:1249 [inline]
shmem_evict_inode+0x39e/0xbe0 mm/shmem.c:1379
evict+0x3c2/0xad0 fs/inode.c:837
iput_final fs/inode.c:1951 [inline]
iput.part.0+0x621/0x1190 fs/inode.c:2003
iput+0x35/0x40 fs/inode.c:1966
dentry_unlink_inode+0x29c/0x480 fs/dcache.c:467
__dentry_kill+0x1d0/0x600 fs/dcache.c:670
finish_dput+0x76/0x480 fs/dcache.c:879
dput.part.0+0x451/0x570 fs/dcache.c:928
dput+0x1f/0x30 fs/dcache.c:920
__fput+0x51c/0xb70 fs/file_table.c:476
task_work_run+0x150/0x240 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x87f/0x2bd0 kernel/exit.c:971
do_group_exit+0xd3/0x2a0 kernel/exit.c:1112
get_signal+0x2671/0x26d0 kernel/signal.c:3034
arch_do_signal_or_restart+0x8f/0x7e0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop kernel/entry/common.c:75 [inline]
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline]
irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline]
irqentry_exit+0x38a/0x8c0 kernel/entry/common.c:196
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f456518f751
RSP: 002b:000000000000a420 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f45653e5fa0 RCX: 00007f456518f749
RDX: 0000000000000000 RSI: 000000000000a420 RDI: 0000000000022080
RBP: 00007f4565213f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007f45653e6038 R14: 00007f45653e5fa0 R15: 00007fff7bce6fe8
rcu: rcu_preempt kthread starved for 9220 jiffies! g113321 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:27864 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 21564 Comm: syz.0.3888 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:__lock_release kernel/locking/lockdep.c:5565 [inline]
RIP: 0010:lock_release+0x116/0x2d0 kernel/locking/lockdep.c:5889
Code: 00 8b 50 24 85 d2 0f 85 94 01 00 00 66 83 78 22 1f 76 0c 66 83 68 22 20 66 83 78 22 1f 77 3c 8b 54 24 0c 41 89 96 28 0b 00 00 <48> 8b 00 49 89 86 20 0b 00 00 41 8d 47 ff 39 d0 74 1f 83 c2 01 48
RSP: 0018:ffffc9000f9de9a0 EFLAGS: 00000097
RAX: ffff888092540ba8 RBX: ffff8880b8424608 RCX: ffffc9000f9de9ac
RDX: 0000000000000003 RSI: ffff8880b8424608 RDI: ffff888092540ba8
RBP: 000000000000000a R08: 0000000000000000 R09: fffffbfff1c56c8a
R10: ffffffff8e2b6457 R11: 0000000000000000 R12: ffffffff8198766e
R13: 0000000000000083 R14: ffff888092540000 R15: 0000000000000004
FS: 00007fef8741a6c0(0000) GS:ffff8881248f5000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056269480dbe0 CR3: 0000000062065000 CR4: 00000000003526f0
DR0: 0000000000000001 DR1: fffffffffffffff7 DR2: 0000000000000000
DR3: 000000000000000a DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
do_write_seqcount_end include/linux/seqlock.h:523 [inline]
psi_write_end kernel/sched/psi.c:188 [inline]
psi_task_change+0x2c1/0x540 kernel/sched/psi.c:923
psi_memstall_enter+0x1de/0x310 kernel/sched/psi.c:1075
try_charge_memcg+0x40d/0xd30 mm/memcontrol.c:2387
try_charge mm/memcontrol.c:2530 [inline]
charge_memcg+0x8a/0x230 mm/memcontrol.c:4728
__mem_cgroup_charge+0x2b/0x1e0 mm/memcontrol.c:4745
mem_cgroup_charge include/linux/memcontrol.h:663 [inline]
shmem_alloc_and_add_folio+0x50c/0xc20 mm/shmem.c:1942
shmem_get_folio_gfp+0x67f/0x1610 mm/shmem.c:2556
shmem_get_folio mm/shmem.c:2662 [inline]
shmem_write_begin+0x1a4/0x3b0 mm/shmem.c:3315
generic_perform_write+0x3c4/0x900 mm/filemap.c:4314
shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3490
__kernel_write_iter+0x31a/0xb10 fs/read_write.c:619
dump_emit_page fs/coredump.c:1298 [inline]
dump_user_range+0x413/0xb70 fs/coredump.c:1372
elf_core_dump+0x29c3/0x3c10 fs/binfmt_elf.c:2111
coredump_write fs/coredump.c:1049 [inline]
do_coredump fs/coredump.c:1126 [inline]
vfs_coredump+0x2b85/0x55e0 fs/coredump.c:1200
get_signal+0x22e1/0x26d0 kernel/signal.c:3019
arch_do_signal_or_restart+0x8f/0x7e0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop kernel/entry/common.c:75 [inline]
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline]
irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline]
irqentry_exit+0x38a/0x8c0 kernel/entry/common.c:196
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7fef8658f751
Code: 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 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f
RSP: 002b:fffffffffffffe70 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007fef867e5fa0 RCX: 00007fef8658f749
RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000000000
RBP: 00007fef86613f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fef867e6038 R14: 00007fef867e5fa0 R15: 00007fffd9feb478