rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6020/1:b..l P7663/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=36465, q=856 ncpus=2)
task:syz-executor state:R running task stack:21832 pid:7663 tgid:7663 ppid:7654 task_flags:0x400140 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]
copy_pte_range mm/memory.c:1201 [inline]
copy_pmd_range+0x68c6/0x71d0 mm/memory.c:1261
copy_pud_range mm/memory.c:1298 [inline]
copy_p4d_range mm/memory.c:1322 [inline]
copy_page_range+0xc14/0x1270 mm/memory.c:1410
dup_mmap+0xf57/0x1ac0 mm/mmap.c:1834
dup_mm kernel/fork.c:1485 [inline]
copy_mm+0x13c/0x4b0 kernel/fork.c:1537
copy_process+0x1706/0x3c00 kernel/fork.c:2175
kernel_clone+0x21e/0x840 kernel/fork.c:2605
__do_sys_clone kernel/fork.c:2748 [inline]
__se_sys_clone kernel/fork.c:2732 [inline]
__x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2732
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: 0033:0x7fcfdf385413
RSP: 002b:00007ffd8035e838 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fcfdf385413
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 00005555757907d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 00000000000482a5 R15: 00007ffd8035e9d0
task:udevd state:R running task stack:22408 pid:6020 tgid:6020 ppid:5227 task_flags:0x400140 flags:0x00004002
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: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 7b 51 03 11 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc90004b7f030 EFLAGS: 00000206
RAX: 8ca887ace3a24400 RBX: 0000000000000000 RCX: 8ca887ace3a24400
RDX: 0000000000000000 RSI: ffffffff8dba8b31 RDI: ffffffff8be33980
RBP: ffffffff81cea506 R08: 0000000000000000 R09: ffffffff81cea506
R10: dffffc0000000000 R11: ffffffff81ac3ae0 R12: 0000000000000002
R13: ffffffff8e139f20 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
is_bpf_text_address+0x47/0x2b0 kernel/bpf/core.c:776
kernel_text_address+0xa5/0xe0 kernel/extable.c:125
__kernel_text_address+0xd/0x40 kernel/extable.c:79
unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:369
arch_stack_walk+0xfc/0x150 arch/x86/kernel/stacktrace.c:26
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:388 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:405
kasan_kmalloc include/linux/kasan.h:260 [inline]
__do_kmalloc_node mm/slub.c:4376 [inline]
__kmalloc_noprof+0x27a/0x4f0 mm/slub.c:4388
kmalloc_noprof include/linux/slab.h:909 [inline]
tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_number_perm+0x1e8/0x5a0 security/tomoyo/file.c:723
tomoyo_path_mknod+0x142/0x190 security/tomoyo/tomoyo.c:252
security_path_mknod+0x17e/0x3a0 security/security.c:1899
may_o_create fs/namei.c:3527 [inline]
lookup_open fs/namei.c:3671 [inline]
open_last_lookups fs/namei.c:3807 [inline]
path_openat+0xd56/0x3830 fs/namei.c:4043
do_filp_open+0x1fa/0x410 fs/namei.c:4073
do_sys_openat2+0x121/0x1c0 fs/open.c:1435
do_sys_open fs/open.c:1450 [inline]
__do_sys_openat fs/open.c:1466 [inline]
__se_sys_openat fs/open.c:1461 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1461
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: 0033:0x7f9e12ca7407
RSP: 002b:00007ffdfc3cdb40 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f9e12c1d880 RCX: 00007f9e12ca7407
RDX: 0000000000080241 RSI: 00007ffdfc3ce0a0 RDI: ffffffffffffff9c
RBP: 0000000000000004 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000001b6 R11: 0000000000000202 R12: 000055c0c778ddfc
R13: 000055c0c778ddfc R14: 0000000000000001 R15: 000055c0d187e7d0
rcu: rcu_preempt kthread starved for 10344 jiffies! g36465 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:27160 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:
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 08/18/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: 3e 1d 96 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 73 07 0e 00 f3 0f 1e fa fb f4 13 1d 96 f5 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197de0 EFLAGS: 000002c2
RAX: 2f073f0895f86700 RBX: ffffffff819683f8 RCX: 2f073f0895f86700
RDX: 0000000000000001 RSI: ffffffff8d9b94df RDI: ffffffff8be33980
RBP: ffffc90000197f20 R08: ffff8880b8732f9b R09: 1ffff110170e65f3
R10: dffffc0000000000 R11: ffffed10170e65f4 R12: ffffffff8fa3a130
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff110039d9b40
FS: 0000000000000000(0000) GS:ffff888125d15000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000001f000 CR3: 0000000031778000 CR4: 0000000000350ef0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:757
default_idle_call+0x74/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:190 [inline]
do_idle+0x1e8/0x510 kernel/sched/idle.c:330
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315
common_startup_64+0x13e/0x147