rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P1230/1:b..l P4886/1:b..l
(detected by 0, t=12470 jiffies, g=12857, q=1110)
task:dhcpcd-run-hook state:R running task stack:29328 pid: 4886 ppid: 4885 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6571
preempt_schedule+0xbc/0xd0 kernel/sched/core.c:6596
preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
__raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline]
_raw_spin_unlock+0x36/0x40 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:404 [inline]
filemap_map_pages+0x1054/0x13b0 mm/filemap.c:3353
do_fault_around mm/memory.c:4243 [inline]
do_read_fault mm/memory.c:4258 [inline]
do_fault mm/memory.c:4392 [inline]
handle_pte_fault mm/memory.c:4650 [inline]
__handle_mm_fault mm/memory.c:4785 [inline]
handle_mm_fault+0x25bc/0x4410 mm/memory.c:4883
do_user_addr_fault+0x489/0xc80 arch/x86/mm/fault.c:1355
handle_page_fault arch/x86/mm/fault.c:1443 [inline]
exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1496
asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606
RIP: 0033:0x7ff4d50e0490
RSP: 002b:00007fff10c66798 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 00007fff10c667a8 RCX: 00007ff4d516f670
RDX: 0000000000000000 RSI: 0000000000000018 RDI: 00007ff4d4fd5f60
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 00007ff4d4fd5f50 R11: 0000000000000246 R12: 00005622e9ab9f70
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
task:kworker/u4:4 state:R running task stack:21232 pid: 1230 ppid: 2 flags:0x00004000
Workqueue: writeback wb_workfn (flush-8:0)
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6799
irqentry_exit+0x63/0x70 kernel/entry/common.c:432
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:__test_set_page_writeback+0xc60/0xec0 mm/page-writeback.c:2887
Code: ff e8 84 bc d7 ff 48 ff cb e9 56 f7 ff ff e8 77 bc d7 ff e8 32 04 1b 08 48 85 db 0f 84 d1 fc ff ff e8 64 bc d7 ff fb 4c 89 e7 06 00 00 00 e8 16 a2 06 00 4c 89 e7 e8 fe 3b 21 00 48 c7 44 24
RSP: 0000:ffffc90004fa6ae0 EFLAGS: 00000293
RAX: ffffffff81a164ac RBX: 0000000000000200 RCX: ffff888022bb8000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffea0001c71d40
RBP: ffffc90004fa6c58 R08: ffffffff901d4187 R09: 1ffffffff203a830
R10: dffffc0000000000 R11: fffffbfff203a831 R12: ffffea0001c71d40
R13: 1ffff920009f4d68 R14: 0000000000000000 R15: 0000000000000000
ext4_bio_write_page+0x293/0x1f90 fs/ext4/page-io.c:-1
mpage_submit_page+0x17a/0x210 fs/ext4/inode.c:2113
mpage_process_page_bufs+0x6d8/0x8b0 fs/ext4/inode.c:2227
mpage_prepare_extent_to_map+0xbc2/0xfe0 fs/ext4/inode.c:2655
ext4_writepages+0xa9a/0x2df0 fs/ext4/inode.c:2783
do_writepages+0x476/0x6e0 mm/page-writeback.c:2386
__writeback_single_inode+0x153/0xda0 fs/fs-writeback.c:1657
writeback_sb_inodes+0xa4e/0x1680 fs/fs-writeback.c:1940
__writeback_inodes_wb+0x12a/0x3f0 fs/fs-writeback.c:2011
wb_writeback+0x46f/0xbe0 fs/fs-writeback.c:2116
wb_check_old_data_flush fs/fs-writeback.c:2216 [inline]
wb_do_writeback fs/fs-writeback.c:2269 [inline]
wb_workfn+0xb15/0xf20 fs/fs-writeback.c:2298
process_one_work+0x85f/0x1010 kernel/workqueue.c:2310
worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
rcu: rcu_preempt kthread timer wakeup didn't happen for 8462 jiffies! g12857 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=1 timer-softirq=4457
rcu: rcu_preempt kthread starved for 8463 jiffies! g12857 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:28016 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2117
rcu_gp_fqs_loop+0x2be/0x11d0 kernel/rcu/tree.c:1972
rcu_gp_kthread+0x9b/0x370 kernel/rcu/tree.c:2145
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4887 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:85 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x84/0x290 mm/kasan/generic.c:189
Code: 49 c1 e9 03 4b 8d 1c 21 49 89 df 4d 29 df 49 83 ff 10 7f 29 4d 85 ff 0f 84 38 01 00 00 4c 89 cb 48 f7 d3 4c 01 f3 41 80 3b 00 <0f> 85 86 01 00 00 49 ff c3 48 ff c3 75 ee e9 18 01 00 00 44 89 dd
RSP: 0018:ffffc90000dd0d10 EFLAGS: 00000046
RAX: ffffffff8168e101 RBX: ffffffffffffffff RCX: ffffffff8168e124
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8d89e368
RBP: ffffc90000dd0e98 R08: ffffffff8d89e36f R09: 1ffffffff1b13c6d
R10: dffffc0000000000 R11: fffffbfff1b13c6d R12: dffffc0000000001
R13: ffffffff8816cfb0 R14: 1ffffffff1b13c6d R15: 0000000000000001
FS: 0000555569ea5500(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9254f11560 CR3: 000000007b0a5000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
instrument_atomic_read include/linux/instrumented.h:71 [inline]
test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
cpumask_test_cpu include/linux/cpumask.h:344 [inline]
cpu_online include/linux/cpumask.h:895 [inline]
trace_hrtimer_expire_entry include/trace/events/timer.h:236 [inline]
__run_hrtimer kernel/time/hrtimer.c:1682 [inline]
__hrtimer_run_queues+0x444/0xb70 kernel/time/hrtimer.c:1749
hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
__sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:memcpy+0x49/0x60 mm/kasan/shadow.c:69
Code: e1 e8 6b ee ff ff 84 c0 74 2c 4c 89 ff 48 89 de ba 01 00 00 00 4c 89 e1 e8 54 ee ff ff 84 c0 74 15 4c 89 ff 4c 89 f6 48 89 da <5b> 41 5c 41 5e 41 5f e9 eb 4a fe 07 31 c0 5b 41 5c 41 5e 41 5f c3
RSP: 0018:ffffc900030bfa38 EFLAGS: 00000202
RAX: ffffffff81ccaa01 RBX: 0000000000000010 RCX: ffffffff81ccaa3b
RDX: 0000000000000010 RSI: ffffc900030bfb00 RDI: ffffc900030bfc40
RBP: ffffc900030bfb68 R08: ffffc900030bfc4f R09: 1ffff92000617f89
R10: dffffc0000000000 R11: fffff52000617f8a R12: ffffffff81ccaa3b
R13: 1ffff92000617f8f R14: ffffc900030bfb00 R15: ffffc900030bfc40
step_into+0x37b/0xd10 fs/namei.c:1827
lookup_last fs/namei.c:2439 [inline]
path_lookupat+0x169/0x440 fs/namei.c:2463
filename_lookup+0x214/0x540 fs/namei.c:2492
user_path_at_empty+0x40/0x190 fs/namei.c:2891
do_readlinkat+0xd9/0x490 fs/stat.c:442
__do_sys_readlinkat fs/stat.c:469 [inline]
__se_sys_readlinkat fs/stat.c:466 [inline]
__x64_sys_readlinkat+0x96/0xb0 fs/stat.c:466
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f9254f11587
Code: 00 00 00 41 54 41 ba 00 10 00 00 bf 9c ff ff ff 48 8d 35 34 e2 05 00 55 b8 0b 01 00 00 53 48 81 ec 00 10 00 00 48 89 e2 0f 05 <85> c0 7e 7d 0f b6 14 24 80 fa 5b 74 74 80 fa 2f 0f 85 2d 01 00 00
RSP: 002b:00007ffc7636ba00 EFLAGS: 00000206 ORIG_RAX: 000000000000010b
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f9254f11587
RDX: 00007ffc7636ba00 RSI: 00007f9254f6f7a8 RDI: 00000000ffffff9c
RBP: 00007ffc7636cb18 R08: 00007f92550696f8 R09: 0000000000000000
R10: 0000000000001000 R11: 0000000000000206 R12: 00007ffc7636cb30
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000