rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5981/1:b..l P7185/1:b..l P6033/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=19673, q=613 ncpus=2)
task:udevd state:R running task stack:25272 pid:6033 tgid:6033 ppid:5194 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7190
irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x0/0x90 kernel/kcov.c:320
Code: 7c 11 10 48 89 74 11 18 48 89 44 11 20 e9 93 43 4f 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 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 08 10 80 92 65 8b 15 88 12
RSP: 0018:ffffc9000b7f78d0 EFLAGS: 00000246
RAX: ffffffff823d016c RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff888025611e80 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000b7f7c00 R08: ffffffff823cff74 R09: ffffffff8df41aa0
R10: dffffc0000000000 R11: ffffed100f65aecd R12: ffff88807af10020
R13: ffffc9000b7f7c20 R14: dffffc0000000000 R15: 1ffff1100f5e2004
path_init+0x331/0x1330 fs/namei.c:-1
path_openat+0x19a/0x3dd0 fs/namei.c:4791
do_filp_open+0x1fa/0x410 fs/namei.c:4823
do_sys_openat2+0x121/0x200 fs/open.c:1430
do_sys_open fs/open.c:1436 [inline]
__do_sys_openat fs/open.c:1452 [inline]
__se_sys_openat fs/open.c:1447 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1447
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f10f22a7407
RSP: 002b:00007ffdde6a9440 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f10f29f8880 RCX: 00007f10f22a7407
RDX: 00000000000a0241 RSI: 00007ffdde6aa100 RDI: ffffffffffffff9c
RBP: 000055afc42acc50 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000124 R11: 0000000000000202 R12: 000055afc3f86ad0
R13: 00007ffdde6aa100 R14: 00007ffdde6a9d00 R15: 00007ffdde6a9900
task:syz-executor state:R running task stack:20704 pid:7185 tgid:7185 ppid:7170 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
preempt_schedule_notrace+0x57/0x90 kernel/sched/core.c:7140
preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
rcu_is_watching+0x7f/0xb0 kernel/rcu/tree.c:752
rcu_read_lock include/linux/rcupdate.h:868 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xd4/0x23d0 arch/x86/kernel/unwind_orc.c:495
__unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:773
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf5/0x1f0 mm/page_owner.c:165
__set_page_owner+0x8d/0x4c0 mm/page_owner.c:341
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x234/0x290 mm/page_alloc.c:1857
prep_new_page mm/page_alloc.c:1865 [inline]
get_page_from_freelist+0x24e0/0x2580 mm/page_alloc.c:3915
__alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5210
__alloc_pages_noprof mm/page_alloc.c:5244 [inline]
alloc_pages_bulk_noprof+0x560/0x710 mm/page_alloc.c:5164
alloc_pages_bulk_mempolicy_noprof+0x341/0x1650 mm/mempolicy.c:2794
vm_area_alloc_pages mm/vmalloc.c:3693 [inline]
__vmalloc_area_node mm/vmalloc.c:3863 [inline]
__vmalloc_node_range_noprof+0xa38/0x16a0 mm/vmalloc.c:4051
__vmalloc_node_noprof mm/vmalloc.c:4111 [inline]
vmalloc_noprof+0xb2/0xf0 mm/vmalloc.c:4146
ebt_register_table+0x231/0x10e0 net/bridge/netfilter/ebtables.c:1211
find_inlist_lock_noload+0x183/0x270 net/bridge/netfilter/ebtables.c:343
find_inlist_lock net/bridge/netfilter/ebtables.c:370 [inline]
find_table_lock net/bridge/netfilter/ebtables.c:379 [inline]
do_ebt_get_ctl+0x25d/0x1c50 net/bridge/netfilter/ebtables.c:2468
nf_getsockopt+0x26e/0x290 net/netfilter/nf_sockopt.c:116
ip_getsockopt+0x1c4/0x220 net/ipv4/ip_sockglue.c:1777
do_sock_getsockopt+0x2b4/0x3d0 net/socket.c:2383
__sys_getsockopt net/socket.c:2412 [inline]
__do_sys_getsockopt net/socket.c:2419 [inline]
__se_sys_getsockopt net/socket.c:2416 [inline]
__x64_sys_getsockopt+0x1a5/0x250 net/socket.c:2416
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe46cd9148a
RSP: 002b:00007ffd97c3e288 EFLAGS: 00000246 ORIG_RAX: 0000000000000037
RAX: ffffffffffffffda RBX: 00007fe46cfb4f80 RCX: 00007fe46cd9148a
RDX: 0000000000000082 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000002 R08: 00007ffd97c3e320 R09: 00007ffd97c3dbb7
R10: 00007fe46cfb4f88 R11: 0000000000000246 R12: 00007fe46cfb4f88
R13: 00007fe46cfb4280 R14: 0000000000000003 R15: 00007ffd97c3e320
task:udevd state:R running task stack:23608 pid:5981 tgid:5981 ppid:5194 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7190
irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__page_table_check_zero+0x138/0x3e0 mm/page_table_check.c:139
Code: e8 03 80 3c 28 00 74 0c 48 c7 c7 30 75 9a 8d e8 8e 77 f4 ff 4c 2b 2d 87 d1 67 0b 49 c1 fd 06 4c 89 ef e8 ab f4 ff ff 48 85 c0 <0f> 84 b8 01 00 00 49 89 c7 4c 89 64 24 08 49 ff c5 bf 20 00 00 00
RSP: 0018:ffffc9000b4f7558 EFLAGS: 00000282
RAX: ffff88801e214580 RBX: 0000000000000001 RCX: ffff88802c251e80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: dffffc0000000000 R08: ffffffff8232a2ea R09: ffffffff8df41aa0
R10: dffffc0000000000 R11: ffffed100a5dec8e R12: ffffffff8232a2ea
R13: 000000000007ea78 R14: 0000000000000000 R15: 0000000000000000
page_table_check_free include/linux/page_table_check.h:43 [inline]
free_pages_prepare mm/page_alloc.c:1407 [inline]
__free_frozen_pages+0xbdb/0xd30 mm/page_alloc.c:2943
discard_slab mm/slub.c:3346 [inline]
__put_partials+0x146/0x170 mm/slub.c:3886
__slab_free+0x294/0x320 mm/slub.c:5952
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:4953 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
kmem_cache_alloc_lru_noprof+0x36c/0x6e0 mm/slub.c:5282
shmem_alloc_inode+0x28/0x40 mm/shmem.c:5152
alloc_inode+0x6a/0x1b0 fs/inode.c:346
new_inode+0x22/0x170 fs/inode.c:1175
__shmem_get_inode mm/shmem.c:3068 [inline]
shmem_get_inode+0x347/0xe60 mm/shmem.c:3142
shmem_mknod+0x191/0x360 mm/shmem.c:3872
lookup_open fs/namei.c:4449 [inline]
open_last_lookups fs/namei.c:4549 [inline]
path_openat+0x18bb/0x3dd0 fs/namei.c:4793
do_filp_open+0x1fa/0x410 fs/namei.c:4823
do_sys_openat2+0x121/0x200 fs/open.c:1430
do_sys_open fs/open.c:1436 [inline]
__do_sys_openat fs/open.c:1452 [inline]
__se_sys_openat fs/open.c:1447 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1447
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f10f22a7407
RSP: 002b:00007ffdde6aa520 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f10f29f8880 RCX: 00007f10f22a7407
RDX: 0000000000080241 RSI: 00007ffdde6aaa80 RDI: ffffffffffffff9c
RBP: 0000000000000004 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000001b6 R11: 0000000000000202 R12: 000055afc1b28dfc
R13: 000055afc1b28dfc R14: 0000000000000001 R15: 000055afc3f86ad0
rcu: rcu_preempt kthread starved for 10537 jiffies! g19673 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:27648 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
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+0x510/0xa50 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:
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 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:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: 1e 84 b6 f5 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 53 91 0e 00 f3 0f 1e fa fb f4 f3 83 b6 f5 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197e20 EFLAGS: 000002c6
RAX: 0000000000ebc679 RBX: ffffffff8197149e RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d792d26 RDI: ffffffff8bc08660
RBP: ffffc90000197f10 R08: ffff8880b87336db R09: 1ffff110170e66db
R10: dffffc0000000000 R11: ffffed10170e66dc R12: ffffffff8f822470
R13: 1ffff1100385fb70 R14: 0000000000000001 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125f1f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2620e8 CR3: 000000007c18b000 CR4: 0000000000350ef0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x1be/0x4d0 kernel/sched/idle.c:332
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x147