rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5783/1:b..l rcu: (detected by 1, t=10502 jiffies, g=17305, q=330 ncpus=2) task:syz-executor state:R running task stack:21640 pid:5783 ppid:5777 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x14d2/0x44d0 kernel/sched/core.c:6700 preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6867 preempt_schedule+0xab/0xc0 kernel/sched/core.c:6891 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3a/0x40 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] copy_pte_range mm/memory.c:1106 [inline] copy_pmd_range mm/memory.c:1167 [inline] copy_pud_range mm/memory.c:1204 [inline] copy_p4d_range mm/memory.c:1228 [inline] copy_page_range+0x2b7c/0x3600 mm/memory.c:1322 dup_mmap kernel/fork.c:764 [inline] dup_mm kernel/fork.c:1692 [inline] copy_mm+0x1124/0x1c20 kernel/fork.c:1741 copy_process+0x16d3/0x3d70 kernel/fork.c:2506 kernel_clone+0x21b/0x840 kernel/fork.c:2914 __do_sys_clone kernel/fork.c:3057 [inline] __se_sys_clone kernel/fork.c:3041 [inline] __x64_sys_clone+0x18c/0x1e0 kernel/fork.c:3041 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f74bf385453 RSP: 002b:00007ffe14de77c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f74bf385453 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: 000055557fc1a7d0 R11: 0000000000000246 R12: 0000000000000000 R13: 00000000000927c0 R14: 0000000000046e6a R15: 00007ffe14de7960 rcu: rcu_preempt kthread starved for 10521 jiffies! g17305 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 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:26728 pid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x14d2/0x44d0 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 schedule_timeout+0x160/0x280 kernel/time/timer.c:2167 rcu_gp_fqs_loop+0x302/0x1560 kernel/rcu/tree.c:1667 rcu_gp_kthread+0x99/0x380 kernel/rcu/tree.c:1866 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.6.101-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:ktime_get_with_offset+0xec/0x330 kernel/time/timekeeping.c:890 Code: 4a 8b 0f 00 eb ec e8 43 8b 0f 00 48 8b 05 cc 91 5e 0b 48 89 44 24 10 48 b8 00 00 00 00 00 fc ff df 48 8b 4c 24 18 80 3c 01 00 <74> 08 4c 89 f7 e8 1a d1 66 00 49 8b 06 48 89 44 24 08 e8 dd f9 ff RSP: 0018:ffffc90000007ad8 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: 0000000000013110 RCX: 1ffffffff19a9391 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffffff8e4a84ef R09: 1ffffffff1c9509d R10: dffffc0000000000 R11: fffffbfff1c9509e R12: ffff88805cd4b320 R13: ffff8880587a6750 R14: ffffffff8cd49c88 R15: 000000000000000a FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2d31cff8 CR3: 000000001a34f000 CR4: 00000000003506f0 Call Trace: ktime_get_real include/linux/timekeeping.h:79 [inline] mac80211_hwsim_get_tsf_raw drivers/net/wireless/virtual/mac80211_hwsim.c:1180 [inline] __mac80211_hwsim_beacon_tx+0x1f9/0x550 drivers/net/wireless/virtual/mac80211_hwsim.c:2204 mac80211_hwsim_beacon_tx+0x3e9/0x780 drivers/net/wireless/virtual/mac80211_hwsim.c:2269 __iterate_interfaces+0x243/0x500 net/mac80211/util.c:766 ieee80211_iterate_active_interfaces_atomic+0xdb/0x180 net/mac80211/util.c:802 mac80211_hwsim_beacon+0xbb/0x1b0 drivers/net/wireless/virtual/mac80211_hwsim.c:2295 __run_hrtimer kernel/time/hrtimer.c:1755 [inline] __hrtimer_run_queues+0x51e/0xc40 kernel/time/hrtimer.c:1819 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1836 handle_softirqs+0x280/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:148 Code: cc cc cc cc cc cc cc f3 0f 1e fa 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 66 90 0f 00 2d 83 16 3b 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 66 0f 1f 00 55 41 57 41 56 RSP: 0018:ffffffff8ca07d80 EFLAGS: 000002c2 RAX: 35ca1f5cf31e5500 RBX: ffffffff81619a6b RCX: 35ca1f5cf31e5500 RDX: 0000000000000001 RSI: ffffffff8aaaba40 RDI: ffffffff8afc6780 RBP: ffffffff8ca07eb8 R08: ffff8880b8e36d4b R09: 1ffff110171c6da9 R10: dffffc0000000000 R11: ffffed10171c6daa R12: ffffffff8e4a84e8 R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1952670 arch_safe_halt arch/x86/include/asm/paravirt.h:108 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:753 default_idle_call+0x6c/0xa0 kernel/sched/idle.c:97 cpuidle_idle_call kernel/sched/idle.c:170 [inline] do_idle+0x1eb/0x510 kernel/sched/idle.c:282 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:380 rest_init+0x2e2/0x300 init/main.c:732 arch_call_rest_init+0xe/0x10 init/main.c:829 start_kernel+0x459/0x4e0 init/main.c:1074 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:555 x86_64_start_kernel+0x60/0x60 arch/x86/kernel/head64.c:536 secondary_startup_64_no_verify+0x179/0x17b