rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...0: (0 ticks this GP) idle=450c/0/0x1 softirq=24510/24510 fqs=1134 (detected by 1, t=10502 jiffies, g=36649, q=204 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:__kasan_check_write+0x0/0x10 mm/kasan/shadow.c:37 Code: 8c eb 0a 48 c7 c7 d6 d0 43 8c 48 89 de e8 78 b2 3b 08 31 ed eb d7 00 00 cc cc 89 f6 48 8b 0c 24 31 d2 e9 a3 ec ff ff 0f 1f 00 <89> f6 48 8b 0c 24 ba 01 00 00 00 e9 90 ec ff ff 55 41 56 53 48 89 RSP: 0018:ffffc90000007bb8 EFLAGS: 00000056 RAX: 00000000ffffff01 RBX: ffff88805e3072e8 RCX: ffffffff81643a0e RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90000007c00 RBP: ffffc90000007c70 R08: dffffc0000000000 R09: ffffed100bc60e5e R10: ffffed100bc60e5e R11: 1ffff1100bc60e5d R12: ffff88805e3072f8 R13: ffff88805e3072f0 R14: 1ffff1100bc60e5f R15: 1ffff1100bc60e5e FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055556e6c25c8 CR3: 000000005c504000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read_write include/linux/instrumented.h:102 [inline] atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:542 [inline] queued_spin_lock include/asm-generic/qspinlock.h:111 [inline] do_raw_spin_lock+0x11d/0x280 kernel/locking/spinlock_debug.c:115 spin_lock include/linux/spinlock.h:351 [inline] advance_sched+0x47/0x970 net/sched/sch_taprio.c:700 __run_hrtimer kernel/time/hrtimer.c:1747 [inline] __hrtimer_run_queues+0x554/0xd60 kernel/time/hrtimer.c:1811 hrtimer_interrupt+0x3c5/0x9c0 kernel/time/hrtimer.c:1873 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline] __sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:742 Code: 48 89 df e8 d7 47 af f7 e9 4c ff ff ff e8 ad 07 f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 66 90 0f 00 2d 67 e4 64 00 fb f4 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48 RSP: 0018:ffffffff8c807d88 EFLAGS: 000002c6 RAX: b3946bf23aca1e00 RBX: ffffffff8a21bec7 RCX: b3946bf23aca1e00 RDX: 0000000000000001 RSI: ffffffff8a8c0580 RDI: ffffffff8adef3a0 RBP: ffffffff8c807ec0 R08: dffffc0000000000 R09: ffffed10171c6afa R10: ffffed10171c6afa R11: 1ffff110171c6af9 R12: 0000000000000000 R13: dffffc0000000000 R14: ffffffff8c8bc740 R15: 1ffffffff1c3edd6 default_idle_call+0x84/0xc0 kernel/sched/idle.c:109 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x1fc/0x570 kernel/sched/idle.c:303 cpu_startup_entry+0x3f/0x60 kernel/sched/idle.c:401 rest_init+0x2dc/0x300 init/main.c:745 arch_call_rest_init+0xa/0xa init/main.c:905 start_kernel+0x490/0x539 init/main.c:1152 secondary_startup_64_no_verify+0xcf/0xdb rcu: rcu_preempt kthread starved for 4830 jiffies! g36649 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:26912 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706 rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:742 Code: 48 89 df e8 d7 47 af f7 e9 4c ff ff ff e8 ad 07 f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 66 90 0f 00 2d 67 e4 64 00 fb f4 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48 RSP: 0018:ffffc90000177de8 EFLAGS: 000002c6 RAX: 88d4f0b4ee497700 RBX: ffffffff8a21bec7 RCX: 88d4f0b4ee497700 RDX: 0000000000000001 RSI: ffffffff8a8c0580 RDI: ffffffff8adef3a0 RBP: ffffc90000177f20 R08: dffffc0000000000 R09: ffffed10171e6afa R10: ffffed10171e6afa R11: 1ffff110171e6af9 R12: 0000000000000001 R13: dffffc0000000000 R14: ffff888017731dc0 R15: 1ffffffff1c3edd6 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f042599a390 CR3: 00000000269e8000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: default_idle_call+0x84/0xc0 kernel/sched/idle.c:109 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x1fc/0x570 kernel/sched/idle.c:303 cpu_startup_entry+0x3f/0x60 kernel/sched/idle.c:401 start_secondary+0xe4/0xf0 arch/x86/kernel/smpboot.c:281 secondary_startup_64_no_verify+0xcf/0xdb