rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P27950/1:b..l P27986/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=162185, q=230 ncpus=2)
task:syz.2.4787 state:R running task stack:25096 pid:27986 tgid:27986 ppid:20666 task_flags:0x40004c flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7145
preempt_schedule+0xae/0xc0 kernel/sched/core.c:7169
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
zap_pte_range mm/memory.c:1756 [inline]
zap_pmd_range mm/memory.c:1818 [inline]
zap_pud_range mm/memory.c:1847 [inline]
zap_p4d_range mm/memory.c:1868 [inline]
unmap_page_range+0x3a79/0x4370 mm/memory.c:1889
unmap_single_vma mm/memory.c:1932 [inline]
unmap_vmas+0x399/0x580 mm/memory.c:1976
exit_mmap+0x248/0xb50 mm/mmap.c:1280
__mmput+0x118/0x430 kernel/fork.c:1129
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
__do_sys_exit_group kernel/exit.c:1113 [inline]
__se_sys_exit_group kernel/exit.c:1111 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1111
x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f90dd18eba9
RSP: 002b:00007fff13099af8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f90dd18eba9
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fff13099b5c R08: 0000001913099bef R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000144
R13: 00000000000927c0 R14: 0000000000224b24 R15: 00007fff13099bb0
task:syz.5.4777 state:R running task stack:25128 pid:27950 tgid:27945 ppid:27378 task_flags:0x400140 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288
irqentry_exit+0x6f/0x90 kernel/entry/common.c:197
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__update_page_owner_free_handle+0x186/0x470 mm/page_owner.c:272
Code: 18 4c 89 64 24 20 66 83 7c 24 04 1f 0f 87 8e 01 00 00 e8 bd 2d 93 ff 4c 89 f7 4c 8b 6c 24 28 4c 89 ee e8 0d 30 93 ff 4d 39 f5 <0f> 84 2c 02 00 00 48 8b 2d 1d c0 fa 0b 4c 01 fd 83 3c 24 00 4c 89
RSP: 0018:ffffc9000441f430 EFLAGS: 00000246
RAX: ffffffff822c8133 RBX: dffffc0000000000 RCX: ffff88807f581e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001
RBP: ffff88801dd71af4 R08: ffff88801dd71ab7 R09: 1ffff11003bae356
R10: dffffc0000000000 R11: ffffed1003bae357 R12: 000000000006c9f0
R13: 0000000000000001 R14: 0000000000000001 R15: ffff88801dd71b00
__reset_page_owner+0x85/0x1f0 mm/page_owner.c:309
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1395 [inline]
free_unref_folios+0xdbd/0x1520 mm/page_alloc.c:2952
folios_put_refs+0x559/0x640 mm/swap.c:997
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+0x504/0x9c0 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+0x1d4/0x260 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:43
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: 0033:0x7f1fd218d80a
RSP: 002b:00007f1fd2fcce50 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: ffffffffffffffff RCX: 00007f1fd218d80a
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000003 R08: 0000000000000000 R09: 000000000010a800
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000016
R13: 00007f1fd2fcceb0 R14: 0000000000005586 R15: 0000200000000600
rcu: rcu_preempt kthread starved for 9839 jiffies! g162185 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:27016 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+0x3fc/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:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 27969 Comm: syz.3.4782 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:245 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x8/0x90 kernel/kcov.c:321
Code: 48 89 44 11 20 e9 63 8d 50 ff cc 0f 1f 80 00 00 00 00 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 0c 25 08 b0 a0 92 65 8b 15 58 fc e0 10 81 e2 00 01 ff 00
RSP: 0018:ffffc90003fefeb0 EFLAGS: 00000046
RAX: ffffffff816889eb RBX: 0000000000000000 RCX: ffffffff816889c1
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffff888039ac3c07 R09: 1ffff11007358780
R10: dffffc0000000000 R11: ffffed1007358781 R12: 0000000000000000
R13: 000000000000000f R14: ffff888039ac5540 R15: dffffc0000000000
FS: 00007f7cafba76c0(0000) GS:ffff888125d15000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2e912ff8 CR3: 0000000098449000 CR4: 0000000000350ef0
Call Trace:
fpregs_assert_state_consistent+0x9b/0x150 arch/x86/kernel/fpu/core.c:887
arch_exit_to_user_mode_prepare+0x9/0x50 arch/x86/include/asm/entry-common.h:63
exit_to_user_mode_prepare include/linux/irq-entry-common.h:227 [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+0x177/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7caedb72e0
Code: 83 c0 16 83 e0 f7 74 12 50 48 8d 3d 8a 3e 08 00 e8 25 90 f8 ff 0f 1f 44 00 00 c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 <83> ff 21 74 0b c3 66 2e 0f 1f 84 00 00 00 00 00 55 53 48 89 f3 48
RSP: 002b:00007f7cafba6b38 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007f7caefd5fa8 RCX: 00007f7caed8eba9
RDX: 00007f7cafba6b40 RSI: 00007f7cafba6c70 RDI: 0000000000000021
RBP: 00007f7caefd5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7caefd6038 R14: 00007ffc4f641af0 R15: 00007ffc4f641bd8