rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=abe4/1/0x4000000000000000 softirq=65821/65822 fqs=0
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P14982/1:b..l
rcu: (detected by 0, t=10506 jiffies, g=65665, q=327 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 14988 Comm: syz.8.2213 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:lookup_object lib/debugobjects.c:440 [inline]
RIP: 0010:debug_object_deactivate+0xc0/0x3a0 lib/debugobjects.c:892
Code: 00 00 00 4d 85 ed 74 49 45 31 e4 eb 0c 4d 8b 6d 00 41 ff c4 4d 85 ed 74 38 49 8d 5d 18 48 89 dd 48 c1 ed 03 42 80 7c 35 00 00 <74> 08 48 89 df e8 96 55 75 fd 4c 39 3b 74 41 4c 89 e8 48 c1 e8 03
RSP: 0018:ffffc90000a08d80 EFLAGS: 00000046
RAX: 1ffffffff34dded3 RBX: ffff888027a32ad0 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90000a08ce0
RBP: 1ffff11004f4655a R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200014119c R12: 0000000000000000
R13: ffff888027a32ab8 R14: dffffc0000000000 R15: ffff888051062300
FS: 0000000000000000(0000) GS:ffff88812531e000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7ead1e9f00 CR3: 0000000035967000 CR4: 0000000000350ef0
Call Trace:
debug_hrtimer_deactivate kernel/time/hrtimer.c:490 [inline]
__run_hrtimer kernel/time/hrtimer.c:1898 [inline]
__hrtimer_run_queues+0x23a/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:rcu_read_lock include/linux/rcupdate.h:839 [inline]
RIP: 0010:class_rcu_constructor include/linux/rcupdate.h:1181 [inline]
RIP: 0010:unwind_next_frame+0xd7/0x2550 arch/x86/kernel/unwind_orc.c:495
Code: 31 f6 31 d2 b9 02 00 00 00 45 31 c0 45 31 c9 41 57 e8 0d b9 2a 00 48 83 c4 08 e8 14 48 40 0a 85 c0 74 3a e8 0b e1 33 00 84 c0 <75> 31 e8 02 48 40 0a 85 c0 74 28 80 3d 7c 13 a6 0e 00 75 1f c6 05
RSP: 0018:ffffc90004056d78 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffffff81aecb06 RCX: 0000000080000001
RDX: 000000005a44979c RSI: ffffffff8c289440 RDI: ffffffff8c289400
RBP: dffffc0000000000 R08: ffffffff81770256 R09: ffffffff8e95cce0
R10: dffffc0000000000 R11: ffffffff81b0f560 R12: ffffc90004056e80
R13: 1ffff9200080adc9 R14: ffffc90004056e48 R15: ffffffff81770256
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
save_stack+0x122/0x230 mm/page_owner.c:165
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1402 [inline]
free_unref_folios+0xcec/0x1480 mm/page_alloc.c:3004
folios_put_refs+0x9ff/0xb40 mm/swap.c:1008
folio_batch_release include/linux/folio_batch.h:101 [inline]
shmem_undo_range+0x52c/0x1660 mm/shmem.c:1149
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+0x1a2/0x5e0 fs/dcache.c:670
finish_dput+0xc9/0x480 fs/dcache.c:879
__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
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:328 [inline]
do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd335f9c819
Code: Unable to access opcode bytes at 0x7fd335f9c7ef.
RSP: 002b:00007fd336e4b0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007fd336216188 RCX: 00007fd335f9c819
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fd336216188
RBP: 00007fd336216180 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd336216218 R14: 00007ffc0af24a70 R15: 00007ffc0af24b58
task:syz.1.2212 state:R running task stack:26696 pid:14982 tgid:14980 ppid:5835 task_flags:0x40054c flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x17b4/0x5680 kernel/sched/core.c:7188
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7369
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:169 [inline]
_raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:190
spin_unlock include/linux/spinlock.h:390 [inline]
zap_pte_range mm/memory.c:1948 [inline]
zap_pmd_range mm/memory.c:2004 [inline]
zap_pud_range mm/memory.c:2032 [inline]
zap_p4d_range mm/memory.c:2053 [inline]
__zap_vma_range+0x3d17/0x4b40 mm/memory.c:2093
unmap_vmas+0x379/0x530 mm/memory.c:2162
exit_mmap+0x280/0x9e0 mm/mmap.c:1300
__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:328 [inline]
do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f79d459c819
RSP: 002b:00007f79d5453028 EFLAGS: 00000246 ORIG_RAX: 0000000000000097
RAX: 0000000000000000 RBX: 00007f79d4815fa0 RCX: 00007f79d459c819
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 00007f79d4632c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f79d4816038 R14: 00007f79d4815fa0 R15: 00007ffed42286b8
rcu: rcu_preempt kthread starved for 10506 jiffies! g65665 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:26880 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x17b4/0x5680 kernel/sched/core.c:7188
__schedule_loop kernel/sched/core.c:7267 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7282
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: 0 UID: 0 PID: 11971 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216
Code: 8b 3d 54 b1 63 0c 48 89 de 5b e9 63 ea 5f 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0d 38 61 7a 11 65 8b 15 59 61 7a 11 81 e2 00 01 ff 00 74
RSP: 0018:ffffc90002ee7a58 EFLAGS: 00000202
RAX: ffffffff81b9c636 RBX: ffff8880b863c148 RCX: ffff8880301ebd80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90002ee7b90 R08: ffffffff903353f7 R09: 1ffffffff2066a7e
R10: dffffc0000000000 R11: fffffbfff2066a7f R12: 1ffff110170e8169
R13: dffffc0000000000 R14: ffff8880b8740b48 R15: 0000000000000001
FS: 000055556889c500(0000) GS:ffff88812521e000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31913ff8 CR3: 000000007ddbf000 CR4: 0000000000350ef0
Call Trace:
csd_lock_wait kernel/smp.c:342 [inline]
smp_call_function_many_cond+0xfe6/0x13d0 kernel/smp.c:892
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1057
invalidate_bdev+0x71/0xa0 block/bdev.c:100
btrfs_close_bdev fs/btrfs/volumes.c:1129 [inline]
btrfs_close_one_device fs/btrfs/volumes.c:1153 [inline]
close_fs_devices+0x442/0x840 fs/btrfs/volumes.c:1196
btrfs_close_devices+0xcd/0x570 fs/btrfs/volumes.c:1211
btrfs_free_fs_info+0x4f/0x360 fs/btrfs/disk-io.c:1205
deactivate_locked_super+0xbc/0x130 fs/super.c:476
cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312
task_work_run+0x1d9/0x270 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
exit_to_user_mode_loop+0xed/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:328 [inline]
do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f059739da57
Code: a2 c7 05 9c fc 24 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffd87054568 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f0597432048 RCX: 00007f059739da57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd87054620
RBP: 00007ffd87054620 R08: 00007ffd87055620 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd870556b0
R13: 00007f0597432048 R14: 00000000000c69ba R15: 00007ffd870556f0