rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-....: (1 GPs behind) idle=0cd/1/0x4000000000000000 softirq=12698/12699 fqs=4930 (t=10500 jiffies g=17697 q=1554) NMI backtrace for cpu 0 CPU: 0 PID: 6572 Comm: syz.4.592 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_dump_cpu_stacks+0x22d/0x380 kernel/rcu/tree_stall.h:349 print_cpu_stall+0x31f/0x5f0 kernel/rcu/tree_stall.h:633 check_cpu_stall kernel/rcu/tree_stall.h:727 [inline] rcu_pending kernel/rcu/tree.c:3936 [inline] rcu_sched_clock_irq+0x6ec/0x1120 kernel/rcu/tree.c:2619 update_process_times+0x193/0x200 kernel/time/timer.c:2021 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x4b0/0xb60 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x397/0x8b0 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+0x4d/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:might_alloc include/linux/sched/mm.h:206 [inline] RIP: 0010:slab_pre_alloc_hook+0x19/0xc0 mm/slab.h:492 Code: 4b 02 e9 e4 fe ff ff e8 b5 cf 42 ff eb 8b 0f 1f 00 55 41 57 41 56 41 54 53 89 cd 49 89 d7 49 89 f6 48 89 fb 23 2d ff 83 ad 0c <89> ef e8 50 ba f6 ff 89 ef e8 49 bb f6 ff f7 c5 00 04 00 00 74 18 RSP: 0018:ffffc90000007968 EFLAGS: 00000202 RAX: ffffffff87e0c364 RBX: ffff88801c5e4140 RCX: 0000000000000a20 RDX: 0000000000000001 RSI: ffffc900000079a0 RDI: ffff88801c5e4140 RBP: 0000000000000a20 R08: ffff88814cfb85ab R09: 1ffff110299f70b5 R10: dffffc0000000000 R11: ffffed10299f70b6 R12: ffff88801c5e4140 R13: 0000000000000a20 R14: ffffc900000079a0 R15: 0000000000000001 slab_alloc_node mm/slub.c:3139 [inline] kmem_cache_alloc_node+0x47/0x2c0 mm/slub.c:3261 __alloc_skb+0xf4/0x750 net/core/skbuff.c:415 alloc_skb include/linux/skbuff.h:1162 [inline] new_skb drivers/block/aoe/aoecmd.c:67 [inline] aoecmd_cfg_pkts drivers/block/aoe/aoecmd.c:431 [inline] aoecmd_cfg+0x282/0x910 drivers/block/aoe/aoecmd.c:1371 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648 expire_timers kernel/time/timer.c:1699 [inline] __run_timers+0x56c/0x810 kernel/time/timer.c:1970 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983 handle_softirqs+0x336/0x830 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:finish_lock_switch+0x12f/0x290 kernel/sched/core.c:4804 Code: 83 c7 18 be ff ff ff ff e8 be bc 6d 08 85 c0 74 46 4d 85 ff 75 62 0f 1f 44 00 00 48 89 df e8 58 2d 77 08 e8 a3 f2 2a 00 fb 5b <41> 5c 41 5d 41 5e 41 5f 5d c3 48 89 df e8 2f 0e fe ff 43 80 3c 2c RSP: 0018:ffffc900032ff7b8 EFLAGS: 00000282 RAX: add9429380d81f00 RBX: ffff8880588a0000 RCX: add9429380d81f00 RDX: dffffc0000000000 RSI: ffffffff8a2b2b60 RDI: ffffffff8a7a4b40 RBP: 1ffff110171c7613 R08: ffff8880b8e3b30b R09: 1ffff110171c7661 R10: dffffc0000000000 R11: ffffed10171c7662 R12: 1ffff110171c75c1 R13: dffffc0000000000 R14: ffff8880b8e3ae08 R15: 0000000000000000 finish_task_switch+0x12f/0x650 kernel/sched/core.c:4921 context_switch kernel/sched/core.c:5052 [inline] __schedule+0x11cb/0x4350 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 freezable_schedule include/linux/freezer.h:172 [inline] futex_wait_queue_me+0x22b/0x440 kernel/futex/core.c:2866 futex_wait+0x256/0x680 kernel/futex/core.c:2967 do_futex+0xdc2/0x12b0 kernel/futex/core.c:4018 __do_sys_futex kernel/futex/core.c:4095 [inline] __se_sys_futex+0x389/0x420 kernel/futex/core.c:4076 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: 0033:0x7f8773d24559 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:00007f8771f7b0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007f8773faafa8 RCX: 00007f8773d24559 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f8773faafa8 RBP: 00007f8773faafa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8773fab038 R14: 00007ffc763f6e10 R15: 00007ffc763f6ef8