rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P8725/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=27081, q=436 ncpus=2)
task:dhcpcd state:R running task stack:24648 pid:8725 tgid:8725 ppid:5523 task_flags:0x400040 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:memset+0xf/0x20 arch/x86/lib/memset_64.S:38
Code: 44 88 1f e9 ae f4 95 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 49 89 f9 40 88 f0 48 89 d1 aa 4c 89 c8 e9 82 f4 95 f5 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000e3571b0 EFLAGS: 00000202
RAX: 1ffff92001c6ae00 RBX: ffffc9000e3572c0 RCX: 000000000000000f
RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc9000e3572d9
RBP: dffffc0000000000 R08: ffffc9000e3572e7 R09: ffffc9000e3572d8
R10: dffffc0000000000 R11: fffff52001c6ae5d R12: ffffc9000e357780
R13: ffffc9000e3572d8 R14: ffffc9000e357288 R15: ffffc9000e3572d0
unwind_next_frame+0xc98/0x2390 arch/x86/kernel/unwind_orc.c:592
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
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]
__kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4407
kmalloc_noprof include/linux/slab.h:905 [inline]
slab_free_hook mm/slub.c:2374 [inline]
slab_free mm/slub.c:4695 [inline]
kmem_cache_free+0x166/0x400 mm/slub.c:4797
anon_vma_free mm/rmap.c:137 [inline]
__put_anon_vma+0x12b/0x2d0 mm/rmap.c:2764
put_anon_vma include/linux/rmap.h:117 [inline]
unlink_anon_vmas+0x503/0x670 mm/rmap.c:444
free_pgtables+0x72b/0x9c0 mm/memory.c:413
vms_clear_ptes+0x424/0x540 mm/vma.c:1233
vms_complete_munmap_vmas+0x206/0x8a0 mm/vma.c:1277
do_vmi_align_munmap+0x358/0x420 mm/vma.c:1536
do_vmi_munmap+0x253/0x2e0 mm/vma.c:1584
__vm_munmap+0x23b/0x3d0 mm/vma.c:3155
__do_sys_munmap mm/mmap.c:1080 [inline]
__se_sys_munmap mm/mmap.c:1077 [inline]
__x64_sys_munmap+0x60/0x70 mm/mmap.c:1077
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: 0033:0x7f15fbfdc2e7
RSP: 002b:00007fff82a21718 EFLAGS: 00000202 ORIG_RAX: 000000000000000b
RAX: ffffffffffffffda RBX: 0000564a6c040f00 RCX: 00007f15fbfdc2e7
RDX: 0000000000000001 RSI: 000000000002f6d0 RDI: 00007f15fbd6e000
RBP: 00007fff82a21820 R08: 00000000000004f0 R09: 0000000000000002
R10: 00007fff82a21650 R11: 0000000000000202 R12: 00007fff82a21760
R13: 00007f15fbfef000 R14: 0000564a6c040f00 R15: 0000000000000000
rcu: rcu_preempt kthread timer wakeup didn't happen for 10515 jiffies! g27081 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=1 timer-softirq=18220
rcu: rcu_preempt kthread starved for 10521 jiffies! g27081 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27432 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:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 1297 Comm: aoe_tx0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:uart_port_unlock_deref+0x18/0x2f0 drivers/tty/serial/serial_core.c:90
Code: 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 41 55 41 54 53 49 89 f6 48 89 fb e8 fb eb 72 fc 48 85 db <74> 5d 49 bd 00 00 00 00 00 fc ff df 48 c7 c0 60 d2 a3 8f 48 c1 e8
RSP: 0018:ffffc9000424f718 EFLAGS: 00000082
RAX: ffffffff854cc2e5 RBX: ffffffff99df5f20 RCX: ffff8880272fbc00
RDX: 0000000000000000 RSI: 0000000000000212 RDI: ffffffff99df5f20
RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000849ec0 R12: dffffc0000000000
R13: dffffc0000000000 R14: 0000000000000212 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125d15000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007feee7900100 CR3: 000000005733c000 CR4: 0000000000350ef0
Call Trace:
uart_write_room+0xe4/0x170 drivers/tty/serial/serial_core.c:650
handle_tx+0x163/0x610 drivers/net/caif/caif_serial.c:212
__netdev_start_xmit include/linux/netdevice.h:5222 [inline]
netdev_start_xmit include/linux/netdevice.h:5231 [inline]
xmit_one net/core/dev.c:3839 [inline]
dev_hard_start_xmit+0x2d7/0x830 net/core/dev.c:3855
__dev_queue_xmit+0x1b8d/0x3b50 net/core/dev.c:4725
dev_queue_xmit include/linux/netdevice.h:3361 [inline]
tx+0x6b/0x190 drivers/block/aoe/aoenet.c:62
kthread+0x1d0/0x3e0 drivers/block/aoe/aoecmd.c:1241
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