rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P16656/1:b..l P8080/1:b..l
rcu: (detected by 1, t=10503 jiffies, g=114977, q=1496 ncpus=2)
task:udevd state:R running task stack:24144 pid:8080 tgid:8080 ppid:4986 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
preempt_schedule_notrace+0x57/0x90 kernel/sched/core.c:7506
preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
rcu_is_watching+0x7f/0xb0 kernel/rcu/tree.c:753
rcu_read_unlock include/linux/rcupdate.h:869 [inline]
class_rcu_destructor include/linux/rcupdate.h:1183 [inline]
unwind_next_frame+0x1b66/0x2550 arch/x86/kernel/unwind_orc.c:709
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
__set_page_owner+0x8d/0x4c0 mm/page_owner.c:341
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1859
prep_new_page mm/page_alloc.c:1867 [inline]
get_page_from_freelist+0x21fa/0x2270 mm/page_alloc.c:3946
__alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5304
alloc_slab_page mm/slub.c:3294 [inline]
allocate_slab+0x79/0x5e0 mm/slub.c:3408
new_slab mm/slub.c:3454 [inline]
refill_objects+0x2d5/0x350 mm/slub.c:7338
refill_sheaf mm/slub.c:2832 [inline]
__pcs_replace_empty_main+0x2bf/0x6b0 mm/slub.c:4703
alloc_from_pcs mm/slub.c:4801 [inline]
slab_alloc_node mm/slub.c:4933 [inline]
__do_kmalloc_node mm/slub.c:5361 [inline]
__kmalloc_noprof+0x485/0x720 mm/slub.c:5387
_kmalloc_noprof include/linux/slab.h:973 [inline]
tomoyo_realpath_from_path+0xef/0x640 security/tomoyo/realpath.c:251
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_perm+0x283/0x560 security/tomoyo/file.c:827
security_inode_getattr+0x12b/0x310 security/security.c:1895
vfs_getattr+0x23/0x70 fs/stat.c:259
vfs_statx_path+0x2b/0x230 fs/stat.c:299
vfs_statx+0x12e/0x200 fs/stat.c:356
vfs_fstatat+0x11b/0x170 fs/stat.c:373
__do_sys_newfstatat fs/stat.c:538 [inline]
__se_sys_newfstatat fs/stat.c:532 [inline]
__x64_sys_newfstatat+0x151/0x200 fs/stat.c:532
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9e68311b0a
RSP: 002b:00007fff47d555d8 EFLAGS: 00000202 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 0000563be0161024 RCX: 00007f9e68311b0a
RDX: 00007fff47d555e0 RSI: 00007fff47d55670 RDI: 00000000ffffff9c
RBP: 0000563c024f5f10 R08: 0000563be0161024 R09: 0000000000000000
R10: 0000000000000100 R11: 0000000000000202 R12: 0000563c024f6000
R13: 00007fff47d55670 R14: 00007fff47d577b0 R15: 0000563be0167bcc
task:udevadm state:R running task stack:24424 pid:16656 tgid:16656 ppid:5900 task_flags:0x400000 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7556
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
irqentry_exit+0x14f/0x8f0 kernel/entry/common.c:167
asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:679
RIP: 0010:unwind_next_frame+0xf8/0x2550 include/linux/rcupdate.h:-1
Code: f5 c9 0e 00 75 1f c6 05 1b f5 c9 0e 01 48 c7 c7 40 b3 e9 8b be 4a 03 00 00 48 c7 c2 80 b3 e9 8b e8 2d 7b 2b 00 48 89 6c 24 38 <48> 89 5c 24 40 49 8d 5e 50 48 89 d8 48 c1 e8 03 48 89 44 24 28 42
RSP: 0018:ffffc90006c075c8 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffffff816d83c3 RCX: 0000000080000001
RDX: 00000000c1e3b5cc RSI: ffffffff8c4bda60 RDI: ffffffff8c4bda20
RBP: 1ffff92000d80ee0 R08: ffffffff8176f27f R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8eb59c60 R12: dffffc0000000000
R13: ffffffff8176f27f R14: ffffc90006c076c8 R15: 1ffff92000d80ed9
__unwind_start+0x514/0x660 arch/x86/kernel/unwind_orc.c:787
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xe3/0x150 arch/x86/kernel/stacktrace.c:24
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
kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2705 [inline]
slab_free mm/slub.c:6405 [inline]
kfree+0x1c5/0x640 mm/slub.c:6720
tomoyo_path_perm+0x403/0x560 security/tomoyo/file.c:847
security_inode_getattr+0x12b/0x310 security/security.c:1895
vfs_getattr fs/stat.c:259 [inline]
vfs_fstat fs/stat.c:281 [inline]
__do_sys_newfstat fs/stat.c:551 [inline]
__se_sys_newfstat fs/stat.c:546 [inline]
__x64_sys_newfstat+0x133/0x270 fs/stat.c:546
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc393d11ad7
RSP: 002b:00007ffe342b7638 EFLAGS: 00000297 ORIG_RAX: 0000000000000005
RAX: ffffffffffffffda RBX: 000055cde79ea2a0 RCX: 00007fc393d11ad7
RDX: 00007fc393defea0 RSI: 00007ffe342b7640 RDI: 0000000000000005
RBP: 00007fc393defff0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000297 R12: 000000000000000a
R13: 0000000000003fff R14: 0000000000000000 R15: 000055cde79ea2a0
rcu: rcu_preempt kthread starved for 10583 jiffies! g114977 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:27736 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7556
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
irqentry_exit+0x14f/0x8f0 kernel/entry/common.c:167
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:write_comp_data kernel/kcov.c:246 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x39/0x90 kernel/kcov.c:314
Code: 11 65 8b 0d 59 4a a6 11 81 e1 00 01 ff 00 74 11 81 f9 00 01 00 00 75 5b 83 ba 24 17 00 00 00 74 52 8b 8a f8 16 00 00 83 f9 03 <75> 47 48 8b 8a 00 17 00 00 44 8b 8a fc 16 00 00 49 c1 e1 03 4c 8b
RSP: 0018:ffffc90000157a90 EFLAGS: 00000293
RAX: ffffffff81b2580e RBX: 0000000080000000 RCX: 0000000000000000
RDX: ffff88801dae8000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000157bd0 R08: ffffffff905786f7 R09: 1ffffffff20af0de
R10: dffffc0000000000 R11: fffffbfff20af0df R12: ffffc90000157b00
R13: ffffc90000157b00 R14: 0000000000000000 R15: ffffffff81b25788
__timer_delete_sync+0x10e/0x520 kernel/time/timer.c:1611
schedule_timeout+0x15a/0x2c0 kernel/time/sleep_timeout.c:100
rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2123
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2325
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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/10/2026
RIP: 0010:clear_preempt_need_resched arch/x86/include/asm/preempt.h:66 [inline]
RIP: 0010:__schedule+0x96b/0x56c0 kernel/sched/core.c:7190
Code: 42 80 3c 28 00 74 05 e8 a3 5c 63 f6 49 89 9f a8 0b 00 00 48 8b 5c 24 20 48 89 df be 08 00 00 00 e8 3a 5e 63 f6 f0 48 83 23 cf <65> 81 0d 8a 18 9c 07 00 00 00 80 49 81 c7 f8 0b 00 00 4c 89 f8 48
RSP: 0018:ffffffff8e807be0 EFLAGS: 00000006
RAX: 1ffff110170c7701 RBX: ffffffff8e88ef40 RCX: ffffffff8bd0a796
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffffff8e88ef40
RBP: ffffffff8e807dd0 R08: ffffffff8e88ef47 R09: 1ffffffff1d11de8
R10: dffffc0000000000 R11: fffffbfff1d11de9 R12: ffffffff8e88f728
R13: dffffc0000000000 R14: ffff88802f1b8000 R15: ffff8880b863b100
FS: 0000000000000000(0000) GS:ffff888124f54000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fab30022fe8 CR3: 0000000029b79000 CR4: 0000000000350ef0
Call Trace:
schedule_idle+0x51/0x90 kernel/sched/core.c:7352
do_idle+0x4a6/0x540 kernel/sched/idle.c:384
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:454
rest_init+0x2de/0x300 init/main.c:717
start_kernel+0x392/0x3e0 init/main.c:1175
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x137/0x1b0 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x157