rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P2/1:b..l P5842/1:b..l P5820/1:b..l P7374/3:b..l
rcu: (detected by 1, t=10503 jiffies, g=26433, q=855 ncpus=2)
task:syz.4.440 state:R running task stack:21568 pid:7374 tgid:7374 ppid:5843 task_flags:0x400640 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6911
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7095
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:186
spin_unlock include/linux/spinlock.h:389 [inline]
filemap_map_pages+0x1a2a/0x2130 mm/filemap.c:3941
do_fault_around mm/memory.c:5757 [inline]
do_read_fault mm/memory.c:5790 [inline]
do_fault mm/memory.c:5933 [inline]
do_pte_missing+0x211a/0x3490 mm/memory.c:4477
handle_pte_fault mm/memory.c:6317 [inline]
__handle_mm_fault mm/memory.c:6455 [inline]
handle_mm_fault+0x1bec/0x3310 mm/memory.c:6624
faultin_page mm/gup.c:1126 [inline]
__get_user_pages+0x165b/0x29d0 mm/gup.c:1428
__get_user_pages_locked mm/gup.c:1692 [inline]
get_dump_page+0x1b5/0x410 mm/gup.c:2192
dump_user_range+0x20a/0x12d0 fs/coredump.c:1367
elf_core_dump+0x34c2/0x3ad0 fs/binfmt_elf.c:2110
coredump_write+0x1216/0x1910 fs/coredump.c:1050
do_coredump fs/coredump.c:1127 [inline]
vfs_coredump+0x36a9/0x4280 fs/coredump.c:1201
get_signal+0x1107/0x1330 kernel/signal.c:3019
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 kernel/entry/common.c:98 [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+0x176/0x620 kernel/entry/common.c:219
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x2f7fb9020856
RSP: 002b:0000200000000188 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f6542c15fa0 RCX: 00007f654299c819
RDX: 00002000000001c0 RSI: 0000200000000180 RDI: 0000000000004000
RBP: 00007f6542a32c91 R08: 0000200000000240 R09: 0000200000000240
R10: 0000200000000200 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f6542c16038 R14: 00007f6542c15fa0 R15: 00007f6542d3fa48
task:syz-executor state:R running task stack:23904 pid:5820 tgid:5820 ppid:5813 task_flags:0x40050c flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6911
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7095
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:186
spin_unlock include/linux/spinlock.h:389 [inline]
zap_pte_range mm/memory.c:1959 [inline]
zap_pmd_range mm/memory.c:2021 [inline]
zap_pud_range mm/memory.c:2049 [inline]
zap_p4d_range mm/memory.c:2070 [inline]
unmap_page_range+0x3b71/0x48f0 mm/memory.c:2091
unmap_single_vma mm/memory.c:2133 [inline]
unmap_vmas+0x48f/0x6a0 mm/memory.c:2171
exit_mmap+0x280/0xa10 mm/mmap.c:1302
__mmput+0x118/0x430 kernel/fork.c:1175
exit_mm+0x168/0x220 kernel/exit.c:581
do_exit+0x6a2/0x23c0 kernel/exit.c:964
do_group_exit+0x21b/0x2d0 kernel/exit.c:1118
get_signal+0x1284/0x1330 kernel/signal.c:3034
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:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbc6915d04e
RSP: 002b:00007ffcf79382f8 EFLAGS: 00000246 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 00005555826c8500 RCX: 00007fbc6915d04e
RDX: 0000000040000000 RSI: 00007ffcf793836c RDI: ffffffffffffffff
RBP: 00007ffcf793836c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000008
R13: 0000000000000003 R14: 00007ffcf79385c8 R15: 0000000000000000
task:udevd state:R running task stack:23904 pid:5842 tgid:5842 ppid:5195 task_flags:0x400140 flags:0x00080800
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6911
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7238
irqentry_exit+0x599/0x620 kernel/entry/common.c:239
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__asan_memset+0x22/0x50 mm/kasan/shadow.c:84
Code: 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 56 53 48 89 d3 89 f5 49 89 fe 48 8b 4c 24 18 48 89 d6 ba 01 00 00 00 e8 1e e5 ff ff <84> c0 74 11 4c 89 f7 89 ee 48 89 da 5b 41 5e 5d e9 99 e2 7f 09 31
RSP: 0018:ffffc900040a6ef8 EFLAGS: 00000256
RAX: ffffc900040a7901 RBX: 0000000000000010 RCX: ffffffff8176985e
RDX: 0000000000000001 RSI: 0000000000000010 RDI: ffffc900040a7038
RBP: 0000000000000000 R08: ffffc900040a7047 R09: 1ffff92000814e08
R10: dffffc0000000000 R11: fffff52000814e09 R12: ffffc900040a7038
R13: 1ffff92000814dff R14: ffffc900040a7038 R15: ffffc900040a7030
unwind_next_frame+0xeae/0x23c0 arch/x86/kernel/unwind_orc.c:607
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:1433 [inline]
__free_frozen_pages+0xc2b/0xdb0 mm/page_alloc.c:2978
__slab_free+0x263/0x2b0 mm/slub.c:5573
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4538 [inline]
slab_alloc_node mm/slub.c:4866 [inline]
__do_kmalloc_node mm/slub.c:5259 [inline]
__kmalloc_noprof+0x316/0x760 mm/slub.c:5272
kmalloc_noprof include/linux/slab.h:954 [inline]
kzalloc_noprof include/linux/slab.h:1188 [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_number_perm+0x246/0x630 security/tomoyo/file.c:728
tomoyo_path_mknod+0x14a/0x1a0 security/tomoyo/tomoyo.c:252
security_path_mknod+0x176/0x370 security/security.c:1392
may_o_create+0x2d/0x370 fs/namei.c:4304
lookup_open fs/namei.c:4445 [inline]
open_last_lookups fs/namei.c:4589 [inline]
path_openat+0x1041/0x3860 fs/namei.c:4833
do_file_open+0x23e/0x4a0 fs/namei.c:4865
do_sys_openat2+0x113/0x200 fs/open.c:1366
do_sys_open fs/open.c:1372 [inline]
__do_sys_openat fs/open.c:1388 [inline]
__se_sys_openat fs/open.c:1383 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1383
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f09afaa7407
RSP: 002b:00007ffe236a71f0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f09b01a3880 RCX: 00007f09afaa7407
RDX: 0000000000080241 RSI: 00007ffe236a7750 RDI: ffffffffffffff9c
RBP: 0000000000000004 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000001b6 R11: 0000000000000202 R12: 000055ad1e1a6dfc
R13: 000055ad1e1a6dfc R14: 0000000000000001 R15: 000055ad1e1c1140
task:kthreadd state:R running task stack:26408 pid:2 tgid:2 ppid:0 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6911
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7238
irqentry_exit+0x599/0x620 kernel/entry/common.c:239
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:unwind_next_frame+0x185f/0x23c0 arch/x86/kernel/unwind_orc.c:663
Code: c0 0f 85 49 0a 00 00 48 89 d0 48 c1 e8 03 0f b6 04 28 84 c0 48 8b 74 24 18 0f 85 56 0a 00 00 48 0f bf 03 48 01 c6 49 8d 56 40 <4c> 89 f7 eb 5d 49 8d 5e 40 48 89 d8 48 c1 e8 03 80 3c 28 00 74 08
RSP: 0018:ffffc90000077358 EFLAGS: 00000287
RAX: fffffffffffffff0 RBX: ffffffff90b355ba RCX: 0000000000000000
RDX: ffffc90000077468 RSI: ffffc900000778f0 RDI: ffffc90000077488
RBP: dffffc0000000000 R08: ffffc90000077487 R09: 0000000000000000
R10: ffffc90000077478 R11: fffff5200000ee91 R12: ffffc90000077478
R13: 1ffff9200000ee87 R14: ffffc90000077428 R15: 1ffffffff2166ab7
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:1433 [inline]
__free_frozen_pages+0xc2b/0xdb0 mm/page_alloc.c:2978
__slab_free+0x263/0x2b0 mm/slub.c:5573
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4538 [inline]
slab_alloc_node mm/slub.c:4866 [inline]
kmem_cache_alloc_node_noprof+0x384/0x690 mm/slub.c:4918
alloc_task_struct_node kernel/fork.c:185 [inline]
dup_task_struct+0x52/0x9a0 kernel/fork.c:916
copy_process+0x508/0x3cd0 kernel/fork.c:2050
kernel_clone+0x248/0x8e0 kernel/fork.c:2653
kernel_thread+0x13f/0x1b0 kernel/fork.c:2714
create_kthread kernel/kthread.c:459 [inline]
kthreadd+0x4ec/0x6e0 kernel/kthread.c:817
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: rcu_preempt kthread starved for 10065 jiffies! g26433 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:28120 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
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+0x51e/0xb90 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: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:__kasan_check_byte+0x2d/0x40 mm/kasan/common.c:578
Code: d6 41 56 53 48 89 f3 49 89 fe e8 8e 15 00 00 84 c0 75 16 be 01 00 00 00 4c 89 f7 31 d2 48 89 d9 89 c3 e8 06 05 00 00 89 d8 5b <41> 5e c3 cc cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90
RSP: 0018:ffffc90000a07d10 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffffff8188054a RCX: 0000000080000102
RDX: 0000000000000000 RSI: ffffffff81768a72 RDI: 1ffffffff1cebcb4
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc90000a07eb8 R11: ffffffff81b0db30 R12: 0000000000000002
R13: ffffffff8e75e5a0 R14: ffffffff8e75e5a0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125554000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000126030 CR3: 000000007b1b2000 CR4: 00000000003526f0
Call Trace:
kasan_check_byte include/linux/kasan.h:402 [inline]
lock_acquire+0x79/0x2e0 kernel/locking/lockdep.c:5842
rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
rcu_read_lock include/linux/rcupdate.h:850 [inline]
class_rcu_constructor include/linux/rcupdate.h:1193 [inline]
unwind_next_frame+0xc2/0x23c0 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:340 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4538 [inline]
slab_alloc_node mm/slub.c:4866 [inline]
kmem_cache_alloc_node_noprof+0x384/0x690 mm/slub.c:4918
kmalloc_reserve net/core/skbuff.c:613 [inline]
__alloc_skb+0x27d/0x7d0 net/core/skbuff.c:713
alloc_skb include/linux/skbuff.h:1383 [inline]
synproxy_send_client_synack+0x172/0xe30 net/netfilter/nf_synproxy_core.c:461
nft_synproxy_eval_v4+0x34a/0x4e0 net/netfilter/nft_synproxy.c:60
nft_synproxy_do_eval+0x305/0x580 net/netfilter/nft_synproxy.c:142
expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
nft_do_chain+0x45e/0x1990 net/netfilter/nf_tables_core.c:285
nft_do_chain_inet+0x29d/0x380 net/netfilter/nft_chain_filter.c:161
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_slow+0xc5/0x220 net/netfilter/core.c:623
nf_hook include/linux/netfilter.h:273 [inline]
NF_HOOK+0x21f/0x3c0 include/linux/netfilter.h:316
NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:318
__netif_receive_skb_one_core net/core/dev.c:6181 [inline]
__netif_receive_skb net/core/dev.c:6294 [inline]
process_backlog+0xaa3/0x1950 net/core/dev.c:6645
__napi_poll+0xae/0x340 net/core/dev.c:7709
napi_poll net/core/dev.c:7772 [inline]
net_rx_action+0x627/0xf70 net/core/dev.c:7929
handle_softirqs+0x22a/0x870 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: 7e 6b 02 c3 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 66 90 0f 00 2d e3 92 19 00 fb f4 fc e9 02 00 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffc90000197e20 EFLAGS: 00000242
RAX: 0000000001d8a5d9 RBX: ffffffff819a9c3a RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8defbe6a RDI: ffffffff8c27d580
RBP: ffffc90000197f10 R08: ffff8880b873399b R09: 1ffff110170e6733
R10: dffffc0000000000 R11: ffffed10170e6734 R12: 0000000000000001
R13: 1ffff11003b59000 R14: 0000000000000001 R15: 1ffff11003b59000
arch_safe_halt arch/x86/kernel/process.c:766 [inline]
default_idle+0x9/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:199 [inline]
do_idle+0x36a/0x5f0 kernel/sched/idle.c:352
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:451
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x147