rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P10647/1:b..l
rcu: (detected by 1, t=10503 jiffies, g=49017, q=1525 ncpus=2)
task:syz.1.1099 state:R running task stack:24936 pid:10647 tgid:10647 ppid:9188 task_flags:0x40044c flags:0x00080003
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7256
irqentry_exit+0x6f/0x90 kernel/entry/common.c:211
asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:unwind_next_frame+0x1170/0x2390 arch/x86/kernel/unwind_orc.c:641
Code: 1e b2 00 48 8b 14 24 4d 89 65 00 41 0f b6 04 2f 84 c0 0f 85 f9 0f 00 00 c6 03 00 4c 8b 64 24 10 4c 8b 7c 24 28 48 8b 44 24 40 <0f> b6 04 28 84 c0 0f 85 8a 0d 00 00 41 0f b6 04 2f 84 c0 0f 85 a1
RSP: 0018:ffffc9000b6e6b58 EFLAGS: 00000246
RAX: 1ffffffff202d151 RBX: ffffc9000b6e6c60 RCX: 0000000000000000
RDX: ffffffff90168a88 RSI: 0000000000000000 RDI: ffffc9000b6e6c88
RBP: dffffc0000000000 R08: ffffc9000b6e6c87 R09: 0000000000000000
R10: ffffc9000b6e6c78 R11: fffff520016dcd91 R12: ffffc9000b6e79e8
R13: ffffc9000b6e6c78 R14: ffffc9000b6e6c28 R15: 1ffffffff202d151
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf5/0x1f0 mm/page_owner.c:156
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:311
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1394 [inline]
free_unref_folios+0xdb3/0x14f0 mm/page_alloc.c:2963
folios_put_refs+0x584/0x670 mm/swap.c:1002
free_pages_and_swap_cache+0x277/0x520 mm/swap_state.c:355
__tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline]
tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
tlb_flush_mmu_free mm/mmu_gather.c:397 [inline]
tlb_flush_mmu+0x3a0/0x680 mm/mmu_gather.c:404
zap_pte_range mm/memory.c:1893 [inline]
zap_pmd_range mm/memory.c:1946 [inline]
zap_pud_range mm/memory.c:1975 [inline]
zap_p4d_range mm/memory.c:1996 [inline]
unmap_page_range+0x3b37/0x4370 mm/memory.c:2017
unmap_single_vma mm/memory.c:2060 [inline]
unmap_vmas+0x399/0x580 mm/memory.c:2104
exit_mmap+0x240/0xb40 mm/mmap.c:1280
__mmput+0x118/0x430 kernel/fork.c:1133
exit_mm+0x1da/0x2c0 kernel/exit.c:582
do_exit+0x648/0x2300 kernel/exit.c:954
do_group_exit+0x21c/0x2d0 kernel/exit.c:1107
get_signal+0x1285/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0xa0/0x790 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x72/0x130 kernel/entry/common.c:40
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/0xfa0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f04c3b8f703
RSP: 002b:00007f04c3f0fae8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: 00007f04c15f4000 RBX: 00007f04c3de63f8 RCX: 00007f04c3b8f703
RDX: 0000000000000003 RSI: 0000000000400000 RDI: 00007f04c15f4000
RBP: 00007f04c3de6360 R08: 00000000000000dc R09: 0000000000000000
R10: 0000000000000011 R11: 0000000000000246 R12: 0000000000000003
R13: 00007f04c3de6360 R14: 00000000000017f3 R15: 0000000000000003
rcu: rcu_preempt kthread starved for 8039 jiffies! g49017 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:27224 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7026
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+0x4bc/0x870 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5199 Comm: udevd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:__kasan_check_read+0xa/0x20 mm/kasan/shadow.c:31
Code: 31 ed eb cf cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 89 f6 48 8b 0c 24 <31> d2 e9 ef e4 ff ff 66 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00
RSP: 0018:ffffc90000007628 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8184e058
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8f7ce370
RBP: ffffc90000007708 R08: ffffffff8f7ce38f R09: 1ffffffff1ef9c71
R10: dffffc0000000000 R11: fffffbfff1ef9c72 R12: 0000000000000806
R13: 0000000100007779 R14: 1ffff92000000ecc R15: dffffc0000000000
FS: 00007f498d606880(0000) GS:ffff88812613b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000284030 CR3: 000000006a1fe000 CR4: 00000000003526f0
Call Trace:
instrument_atomic_read include/linux/instrumented.h:68 [inline]
_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
cpumask_test_cpu include/linux/cpumask.h:646 [inline]
cpu_online include/linux/cpumask.h:1205 [inline]
trace_softirq_raise+0x28/0x110 include/trace/events/irq.h:156
__raise_softirq_irqoff kernel/softirq.c:789 [inline]
raise_softirq_irqoff+0x50/0x100 kernel/softirq.c:762
raise_softirq+0x90/0x120 kernel/softirq.c:782
sched_balance_trigger+0x110/0x8a0 kernel/sched/fair.c:12956
update_process_times+0x270/0x2f0 kernel/time/timer.c:2478
tick_sched_handle kernel/time/tick-sched.c:276 [inline]
tick_nohz_handler+0x39a/0x520 kernel/time/tick-sched.c:297
__run_hrtimer kernel/time/hrtimer.c:1777 [inline]
__hrtimer_run_queues+0x4e0/0xc60 kernel/time/hrtimer.c:1841
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline]
__sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1058
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1052
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:246 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x28/0x90 kernel/kcov.c:314
Code: 90 90 f3 0f 1e fa 48 8b 04 24 65 48 8b 14 25 08 50 6e 92 65 8b 0d 08 38 ae 10 81 e1 00 01 ff 00 74 11 81 f9 00 01 00 00 75 5b <83> ba 7c 16 00 00 00 74 52 8b 8a 58 16 00 00 83 f9 03 75 47 48 8b
RSP: 0018:ffffc90000007b80 EFLAGS: 00000246
RAX: ffffffff892a8411 RBX: 0000000000000000 RCX: 0000000000000100
RDX: ffff88807d1e8000 RSI: 0000000000000000 RDI: 0000000000000008
RBP: 0000000000000040 R08: ffff88807d1e8000 R09: 0000000000000004
R10: 0000000000000003 R11: 0000000000000100 R12: ffff8880b883bc98
R13: dffffc0000000000 R14: ffff8880b883bc88 R15: 1ffff11017107793
cpu_max_bits_warn include/linux/cpumask.h:135 [inline]
cpumask_check include/linux/cpumask.h:142 [inline]
cpumask_test_cpu include/linux/cpumask.h:646 [inline]
cpu_online include/linux/cpumask.h:1205 [inline]
trace_napi_poll+0x31/0x200 include/trace/events/napi.h:14
__napi_poll+0xd6/0x360 net/core/dev.c:7595
napi_poll net/core/dev.c:7657 [inline]
net_rx_action+0x5f7/0xdf0 net/core/dev.c:7784
handle_softirqs+0x286/0x870 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5872
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 5b ed d0 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc90003007218 EFLAGS: 00000206
RAX: b1fb6c188457ff00 RBX: 0000000000000000 RCX: b1fb6c188457ff00
RDX: 0000000000000000 RSI: ffffffff8d8f4632 RDI: ffffffff8bbf0760
RBP: ffffffff81739c45 R08: 0000000000000000 R09: ffffffff81739c45
R10: ffffc900030073d8 R11: ffffffff81ac3ea0 R12: 0000000000000002
R13: ffffffff8df3d6a0 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf5/0x1f0 mm/page_owner.c:156
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:311
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1394 [inline]
__free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2906
discard_slab mm/slub.c:3326 [inline]
__put_partials+0x146/0x170 mm/slub.c:3872
put_cpu_partial+0x1f2/0x2e0 mm/slub.c:3947
__slab_free+0x2b9/0x390 mm/slub.c:5925
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:352
kasan_slab_alloc include/linux/kasan.h:252 [inline]
slab_post_alloc_hook mm/slub.c:4974 [inline]
slab_alloc_node mm/slub.c:5284 [inline]
__do_kmalloc_node mm/slub.c:5645 [inline]
__kmalloc_noprof+0x3c3/0x7f0 mm/slub.c:5658
kmalloc_noprof include/linux/slab.h:961 [inline]
kzalloc_noprof include/linux/slab.h:1094 [inline]
tomoyo_encode2 security/tomoyo/realpath.c:45 [inline]
tomoyo_encode+0x28b/0x550 security/tomoyo/realpath.c:80
tomoyo_realpath_from_path+0x58d/0x5d0 security/tomoyo/realpath.c:283
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_perm+0x213/0x4b0 security/tomoyo/file.c:822
security_inode_getattr+0x12f/0x330 security/security.c:2416
vfs_getattr fs/stat.c:259 [inline]
vfs_statx_path fs/stat.c:299 [inline]
vfs_statx+0x18e/0x550 fs/stat.c:356
vfs_fstatat+0x118/0x170 fs/stat.c:375
__do_sys_newfstatat fs/stat.c:542 [inline]
__se_sys_newfstatat fs/stat.c:536 [inline]
__x64_sys_newfstatat+0x116/0x190 fs/stat.c:536
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f498cf11b0a
Code: 48 8b 15 f1 f2 0d 00 f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 41 89 ca b8 06 01 00 00 0f 05 <3d> 00 f0 ff ff 77 07 31 c0 c3 0f 1f 40 00 48 8b 15 b9 f2 0d 00 f7
RSP: 002b:00007fff78e32f08 EFLAGS: 00000246 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 0000557fa63f9400 RCX: 00007f498cf11b0a
RDX: 00007fff78e32f10 RSI: 0000557fa63e7296 RDI: 00000000ffffff9c
RBP: 0000557fcbead148 R08: 000000001f3c0b8f R09: 3fffffffffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fff78e32f10 R14: 0000000000000000 R15: 0000000000000000