rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6278/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=35209, q=693 ncpus=2)
task:udevd state:R running task stack:22712 pid:6278 tgid:6278 ppid:5196 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7190
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:118 [inline]
RIP: 0010:lock_acquire+0x8b/0x340 kernel/locking/lockdep.c:5844
Code: 0f 84 d7 01 00 00 83 3d 72 b6 e3 0d 00 0f 84 f0 00 00 00 48 8b b4 24 90 00 00 00 4c 89 ef e8 8c 69 89 00 83 3d 55 b6 e3 0d 00 <0f> 84 fa 00 00 00 65 8b 05 58 30 e0 10 85 c0 0f 85 eb 00 00 00 65
RSP: 0018:ffffc9000bc37158 EFLAGS: 00000202
RAX: 0000000000000001 RBX: 0000000000000000 RCX: e1bfa5a4ca691a00
RDX: 0000000000000000 RSI: ffffffff81743fa2 RDI: 1ffffffff1be833c
RBP: ffffffff81743f85 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff52001786e71 R12: 0000000000000002
R13: ffffffff8df419e0 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
__unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:56 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
unpoison_slab_object mm/kasan/common.c:339 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:365
kasan_slab_alloc include/linux/kasan.h:252 [inline]
slab_post_alloc_hook mm/slub.c:4953 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
kmem_cache_alloc_noprof+0x37d/0x710 mm/slub.c:5270
anon_vma_chain_alloc mm/rmap.c:141 [inline]
anon_vma_clone+0xb8/0x4f0 mm/rmap.c:287
__split_vma+0x351/0xa00 mm/vma.c:528
vms_gather_munmap_vmas+0x2e2/0x12f0 mm/vma.c:1362
do_vmi_align_munmap+0x268/0x440 mm/vma.c:1530
do_vmi_munmap+0x253/0x2e0 mm/vma.c:1587
__vm_munmap+0x207/0x380 mm/vma.c:3203
__do_sys_munmap mm/mmap.c:1077 [inline]
__se_sys_munmap mm/mmap.c:1074 [inline]
__x64_sys_munmap+0x60/0x70 mm/mmap.c:1074
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f014cb1e097
RSP: 002b:00007fff262068a8 EFLAGS: 00000246 ORIG_RAX: 000000000000000b
RAX: ffffffffffffffda RBX: 000055ec642e8870 RCX: 00007f014cb1e097
RDX: 000055ec642f6b68 RSI: 0000000000000200 RDI: 00007f014d29c000
RBP: 0000000000000001 R08: 000055ec642ff790 R09: 000055ec642f5340
R10: 0000000000000000 R11: 0000000000000246 R12: 000055ec642e60b0
R13: 00007f014d3c439c R14: 0000000000000200 R15: 0000000000000009
rcu: rcu_preempt kthread starved for 10550 jiffies! g35209 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:27136 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
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+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
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: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:lock_release+0x80/0x3b0 kernel/locking/lockdep.c:5881
Code: 85 e3 0d 00 0f 84 3e 02 00 00 65 8b 05 a9 ff df 10 85 c0 0f 85 2f 02 00 00 65 4c 8b 3c 25 08 60 7e 92 41 83 bf 2c 0b 00 00 00 <0f> 85 18 02 00 00 49 81 3e c0 13 42 93 0f 84 0b 02 00 00 48 c7 44
RSP: 0018:ffffc90000a08350 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffffff90198f01 RCX: 71f0ca361be89d00
RDX: ffffc90000a08401 RSI: ffffffff8bc07bc0 RDI: ffffffff8bc07b80
RBP: dffffc0000000000 R08: ffffc90000a08e10 R09: ffffc90000a084d8
R10: dffffc0000000000 R11: fffff5200014109d R12: ffffc90000a08e20
R13: ffffffff81743f85 R14: ffffffff8df419e0 R15: ffff88801c6adb80
FS: 0000000000000000(0000) GS:ffff888125f3a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f014d29c000 CR3: 000000000dd3a000 CR4: 0000000000350ef0
Call Trace:
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+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680
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:56 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
unpoison_slab_object mm/kasan/common.c:339 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:365
kasan_slab_alloc include/linux/kasan.h:252 [inline]
slab_post_alloc_hook mm/slub.c:4953 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
kmem_cache_alloc_noprof+0x37d/0x710 mm/slub.c:5270
kmem_alloc_batch lib/debugobjects.c:371 [inline]
fill_pool+0x100/0x570 lib/debugobjects.c:403
debug_objects_fill_pool lib/debugobjects.c:725 [inline]
debug_object_assert_init+0x2b1/0x380 lib/debugobjects.c:1003
debug_timer_assert_init kernel/time/timer.c:803 [inline]
debug_assert_init kernel/time/timer.c:848 [inline]
__mod_timer+0x4a/0xf30 kernel/time/timer.c:1025
addrconf_mod_rs_timer+0x51/0xe0 net/ipv6/addrconf.c:331
addrconf_rs_timer+0x45e/0x6a0 net/ipv6/addrconf.c:4047
call_timer_fn+0x16e/0x590 kernel/time/timer.c:1748
expire_timers kernel/time/timer.c:1799 [inline]
__run_timers kernel/time/timer.c:2373 [inline]
__run_timer_base+0x61a/0x860 kernel/time/timer.c:2385
run_timer_base kernel/time/timer.c:2394 [inline]
run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2404
handle_softirqs+0x27d/0x850 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: be f3 b4 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 f3 00 0d 00 f3 0f 1e fa fb f4 93 f3 b4 f5 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197de0 EFLAGS: 000002c6
RAX: 71f0ca361be89d00 RBX: ffffffff81978eba RCX: 71f0ca361be89d00
RDX: 0000000000000001 RSI: ffffffff8d790585 RDI: ffffffff8bc07be0
RBP: ffffc90000197f10 R08: ffff8880b87336db R09: 1ffff110170e66db
R10: dffffc0000000000 R11: ffffed10170e66dc R12: ffffffff8f81fb70
R13: 1ffff110038d5b70 R14: 0000000000000001 R15: 0000000000000001
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x1ea/0x520 kernel/sched/idle.c:332
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x147