rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5828/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=18957, q=397 ncpus=2)
task:udevd state:R running task stack:24592 pid:5828 tgid:5828 ppid:5182 task_flags:0x400140 flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6929
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7256
irqentry_exit+0x36/0x90 kernel/entry/common.c:211
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_release+0x183/0x2f0 kernel/locking/lockdep.c:5893
Code: 0f c1 05 a8 bb 08 12 83 f8 01 0f 85 1d 01 00 00 9c 58 f6 c4 02 0f 85 08 01 00 00 41 f7 c5 00 02 00 00 74 01 fb 48 8b 44 24 10 <65> 48 2b 05 bd 79 08 12 0f 85 58 01 00 00 48 83 c4 18 5b 41 5c 41
RSP: 0018:ffffc9000377f600 EFLAGS: 00000206
RAX: 4c041c40fdea3c00 RBX: ffffffff8e3c4460 RCX: ffffc9000377f60c
RDX: 0000000000000001 RSI: ffffffff8da0489d RDI: ffffffff8bf06e40
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000012560 R12: ffffffff816c1914
R13: 0000000000000202 R14: ffff888079310000 R15: 0000000000000002
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:897 [inline]
class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0x3f9/0x20a0 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
kasan_save_track+0x14/0x30 mm/kasan/common.c:77
poison_kmalloc_redzone mm/kasan/common.c:400 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:417
kasan_kmalloc include/linux/kasan.h:262 [inline]
__do_kmalloc_node mm/slub.c:5642 [inline]
__kmalloc_noprof+0x32f/0x880 mm/slub.c:5654
kmalloc_noprof include/linux/slab.h:961 [inline]
tomoyo_realpath_from_path+0xc2/0x6e0 security/tomoyo/realpath.c:251
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_perm+0x274/0x460 security/tomoyo/file.c:822
security_inode_getattr+0x116/0x290 security/security.c:2416
vfs_getattr fs/stat.c:259 [inline]
vfs_fstat+0x4b/0xe0 fs/stat.c:281
__do_sys_newfstat+0x87/0x100 fs/stat.c:555
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9579d11ad7
RSP: 002b:00007fffb1f20b28 EFLAGS: 00000297 ORIG_RAX: 0000000000000005
RAX: ffffffffffffffda RBX: 0000562284ecb1e0 RCX: 00007f9579d11ad7
RDX: 00007f9579defea0 RSI: 00007fffb1f20b30 RDI: 0000000000000008
RBP: 00007f9579defff0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000297 R12: 000000000000000a
R13: 0000000000003fff R14: 0000000000000000 R15: 0000562284ecb1e0
rcu: rcu_preempt kthread timer wakeup didn't happen for 10531 jiffies! g18957 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=7958
rcu: rcu_preempt kthread starved for 10532 jiffies! g18957 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:28080 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7026
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x675/0x7d0 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: 0 UID: 0 PID: 1296 Comm: aoe_tx0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 36 ea 35 f6 48 89 df e8 1e 3e 36 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 45 46 26 f6 65 8b 05 7e 65 3e 08 85 c0 74 16 5b
RSP: 0018:ffffc9000437f968 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffffffff9add7240 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffffff8da2a259 RDI: ffffffff8bf06e40
RBP: 0000000000000293 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff9081f6d7 R11: 0000000000000001 R12: ffffffff9add7348
R13: 0000000000000003 R14: 0000000000000001 R15: 0000000000000003
FS: 0000000000000000(0000) GS:ffff888124a0a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f957a35691c CR3: 0000000062d97000 CR4: 00000000003526f0
Call Trace:
spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
uart_port_unlock_irqrestore include/linux/serial_core.h:788 [inline]
uart_port_unlock_deref drivers/tty/serial/serial_core.c:91 [inline]
uart_port_unlock_deref drivers/tty/serial/serial_core.c:88 [inline]
uart_write+0x4c1/0xb30 drivers/tty/serial/serial_core.c:626
handle_tx+0x204/0x630 drivers/net/caif/caif_serial.c:222
__netdev_start_xmit include/linux/netdevice.h:5248 [inline]
netdev_start_xmit include/linux/netdevice.h:5257 [inline]
xmit_one net/core/dev.c:3845 [inline]
dev_hard_start_xmit+0x97/0x740 net/core/dev.c:3861
__dev_queue_xmit+0xa46/0x4490 net/core/dev.c:4763
dev_queue_xmit include/linux/netdevice.h:3365 [inline]
tx+0xcc/0x190 drivers/block/aoe/aoenet.c:62
kthread+0x1e4/0x3e0 drivers/block/aoe/aoecmd.c:1241
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245