rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=fcfc/1/0x4000000000000000 softirq=20403/20404 fqs=9
rcu: (detected by 1, t=10502 jiffies, g=14529, q=706 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6728 Comm: syz.4.239 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:rb_insert_color+0x584/0x810 lib/rbtree.c:437
Code: ff ff 48 b8 00 00 00 00 00 fc ff df 4c 89 e2 48 c1 ea 03 80 3c 02 00 0f 85 14 01 00 00 49 c7 04 24 01 00 00 00 48 83 c4 08 5b <5d> 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc 48 8d 45 01 48 89 ea 49
RSP: 0018:ffffc90000007e00 EFLAGS: 00000082
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000003
RDX: 1ffff1100efa5060 RSI: ffff8880b8428698 RDI: ffff888077d28300
RBP: ffff8880b8428698 R08: 0000000000000005 R09: 000000000000001f
R10: 0000000000000003 R11: ffffc90000007ff8 R12: ffff888077d28300
R13: ffff888077d28318 R14: dffffc0000000000 R15: ffff8880b8428698
FS: 0000555569cf6500(0000) GS:ffff88812431a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000001c4 CR3: 0000000020b6f000 CR4: 00000000003526f0
Call Trace:
__rb_add include/linux/rbtree.h:239 [inline]
rb_add_linked include/linux/rbtree.h:281 [inline]
timerqueue_linked_add+0x236/0x430 lib/timerqueue.c:96
enqueue_hrtimer+0x1ad/0x2f0 kernel/time/hrtimer.c:1117
__run_hrtimer kernel/time/hrtimer.c:2048 [inline]
__hrtimer_run_queues+0x6ed/0x9c0 kernel/time/hrtimer.c:2096
hrtimer_interrupt+0x3e5/0x940 kernel/time/hrtimer.c:2215
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
__sysvec_apic_timer_interrupt+0x109/0x470 arch/x86/kernel/apic/apic.c:1068
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0x9e/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:finish_task_switch.isra.0+0x2cd/0x1010 kernel/sched/core.c:5361
Code: 2f 0a 00 00 41 c7 87 20 0e 00 00 00 00 00 00 0f 1f 44 00 00 49 8d 7f 48 e8 30 95 c4 09 e8 5b aa 3c 00 fb 48 8d bb f8 16 00 00 <48> b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 04 02 84
RSP: 0018:ffffc90005d5f8d8 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffff8880536f0000 RCX: ffffffff8211aa2f
RDX: 0000000000000000 RSI: ffffffff8c1d2680 RDI: ffff8880536f16f8
RBP: ffffc90005d5f930 R08: 0000000000000000 R09: fffffbfff21b43d2
R10: 0000000000000000 R11: ffffffff81d4ff9c R12: ffff888050d1ca80
R13: 0000000000000000 R14: ffffffff90da5264 R15: ffff8880b843b340
context_switch kernel/sched/core.c:5507 [inline]
__schedule+0x1264/0x6730 kernel/sched/core.c:7228
__schedule_loop kernel/sched/core.c:7307 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7322
futex_do_wait+0x88/0x180 kernel/futex/waitwake.c:387
__futex_wait+0x1c4/0x300 kernel/futex/waitwake.c:722
futex_wait+0xe6/0x370 kernel/futex/waitwake.c:750
do_futex+0x265/0x440 kernel/futex/syscalls.c:133
__do_sys_futex kernel/futex/syscalls.c:210 [inline]
__se_sys_futex kernel/futex/syscalls.c:191 [inline]
__x64_sys_futex+0x34f/0x4d0 kernel/futex/syscalls.c:191
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6c2179ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd7ef2ae88 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 000000000001962e RCX: 00007f6c2179ce59
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f6c21a15fac
RBP: 0000000000000032 R08: 0000000000000001 R09: 0000000000000000
R10: 00007ffd7ef2af90 R11: 0000000000000246 R12: 00007ffd7ef2afb0
R13: 00007f6c21a15fac R14: 0000000000019660 R15: 00007ffd7ef2af90
rcu: rcu_preempt kthread starved for 10484 jiffies! g14529 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:28416 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5504 [inline]
__schedule+0x125c/0x6730 kernel/sched/core.c:7228
__schedule_loop kernel/sched/core.c:7307 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7322
schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2123
rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2325
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 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: 1 UID: 0 PID: 6734 Comm: syz.3.240 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0x589/0x16c0 kernel/smp.c:892
Code: b8 00 00 00 00 00 fc ff df 48 8b 54 24 08 49 89 d5 49 89 d4 49 c1 ed 03 41 83 e4 07 49 01 c5 41 83 c4 03 e8 b9 95 0c 00 f3 90 <41> 0f b6 45 00 41 38 c4 7c 08 84 c0 0f 85 2c 0f 00 00 8b 45 08 31
RSP: 0018:ffffc90005a9e6f8 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff81fcc98d
RDX: ffff888075ae8000 RSI: ffffffff81fcc967 RDI: ffff888075ae8000
RBP: ffff8880b8443500 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: ffffffff8279a110 R12: 0000000000000003
R13: ffffed10170886a1 R14: 0000000000000001 R15: ffff8880b853c700
FS: 00007f3e2bbcd6c0(0000) GS:ffff88812441a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f03d6d4da08 CR3: 000000007db60000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1057
__flush_tlb_multi arch/x86/include/asm/paravirt.h:46 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
arch_tlbbatch_flush+0x216/0x320 arch/x86/mm/tlb.c:1725
try_to_unmap_flush+0x6f/0xf0 mm/rmap.c:718
shrink_folio_list+0x2fb8/0x60a0 mm/vmscan.c:1586
evict_folios+0x327/0x1960 mm/vmscan.c:4840
try_to_shrink_lruvec+0x249/0x6b0 mm/vmscan.c:4988
lru_gen_shrink_lruvec mm/vmscan.c:5133 [inline]
shrink_lruvec+0x31e/0x25b0 mm/vmscan.c:5893
shrink_node_memcgs mm/vmscan.c:6132 [inline]
shrink_node+0x778/0x3e90 mm/vmscan.c:6176
shrink_zones mm/vmscan.c:6415 [inline]
do_try_to_free_pages+0x33e/0x16d0 mm/vmscan.c:6477
try_to_free_mem_cgroup_pages+0x2bf/0x840 mm/vmscan.c:6799
try_charge_memcg+0x47f/0xdf0 mm/memcontrol.c:2655
obj_cgroup_charge_pages+0x22/0x1d0 mm/memcontrol.c:3097
__memcg_kmem_charge_page+0x1c1/0x4d0 mm/memcontrol.c:3141
__alloc_frozen_pages_noprof+0x365/0x2dc0 mm/page_alloc.c:5321
alloc_pages_mpol+0x1fb/0x540 mm/mempolicy.c:2490
alloc_pages_noprof+0x1a/0x160 mm/mempolicy.c:2581
io_mem_alloc_compound io_uring/memmap.c:30 [inline]
io_region_allocate_pages io_uring/memmap.c:165 [inline]
io_create_region+0x722/0xbe0 io_uring/memmap.c:220
io_allocate_scq_urings io_uring/io_uring.c:2759 [inline]
io_uring_create io_uring/io_uring.c:3050 [inline]
io_uring_setup.cold+0x1285/0x1cae io_uring/io_uring.c:3120
__do_sys_io_uring_setup io_uring/io_uring.c:3154 [inline]
__se_sys_io_uring_setup io_uring/io_uring.c:3145 [inline]
__x64_sys_io_uring_setup+0xc2/0x170 io_uring/io_uring.c:3145
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3e2ad9ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3e2bbccfb8 EFLAGS: 00000206 ORIG_RAX: 00000000000001a9
RAX: ffffffffffffffda RBX: 0000200000000580 RCX: 00007f3e2ad9ce59
RDX: 0000200000001880 RSI: 0000200000000580 RDI: 000000000000437d
RBP: 00007f3e2ae32e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000000 R11: 0000000000000206 R12: 0000200000001880
R13: 0000200000000000 R14: 0000200000000240 R15: 00007ffcd34a76a8