rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=95a4/1/0x4000000000000000 softirq=86645/86646 fqs=0 (detected by 1, t=10506 jiffies, g=129433, q=81 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 17409 Comm: syz-executor.1 Not tainted 6.1.38-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023 RIP: 0010:arch_test_and_set_bit arch/x86/include/asm/bitops.h:138 [inline] RIP: 0010:test_and_set_bit include/asm-generic/bitops/instrumented-atomic.h:72 [inline] RIP: 0010:__netif_schedule+0x8d/0x310 net/core/dev.c:3086 Code: df 4b 89 04 2e 66 43 c7 44 2e 09 f3 f3 43 c6 44 2e 0b f3 e8 d5 8b 0e f9 49 8d bc 24 58 01 00 00 be 08 00 00 00 e8 23 f3 64 f9 <31> db f0 49 0f ba ac 24 58 01 00 00 00 41 0f 93 c7 0f 92 c3 bf 02 RSP: 0018:ffffc90000007be0 EFLAGS: 00000056 RAX: ffffffff887b4f01 RBX: 0000000000000001 RCX: ffffffff887b4f7d RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88807d2a7158 RBP: ffffc90000007cb0 R08: dffffc0000000000 R09: ffffed100fa54e2c R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88807d2a7000 R13: dffffc0000000000 R14: 1ffff92000000f80 R15: 17713374da300000 FS: 0000555555c6c480(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f86084c56be CR3: 000000007534a000 CR4: 00000000003506f0 Call Trace: advance_sched+0x750/0x940 net/sched/sch_taprio.c:754 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x5e5/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline] __sysvec_apic_timer_interrupt+0x156/0x580 arch/x86/kernel/apic/apic.c:1112 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:atomic_inc include/linux/atomic/atomic-instrumented.h:191 [inline] RIP: 0010:__page_dup_rmap include/linux/rmap.h:209 [inline] RIP: 0010:page_dup_file_rmap include/linux/rmap.h:214 [inline] RIP: 0010:copy_present_pte mm/memory.c:965 [inline] RIP: 0010:copy_pte_range mm/memory.c:1081 [inline] RIP: 0010:copy_pmd_range mm/memory.c:1167 [inline] RIP: 0010:copy_pud_range mm/memory.c:1204 [inline] RIP: 0010:copy_p4d_range mm/memory.c:1228 [inline] RIP: 0010:copy_page_range+0x1542/0x4580 mm/memory.c:1326 Code: be 04 00 00 00 e8 7e c7 15 00 f0 41 ff 45 00 48 8b 44 24 18 48 8d 78 30 be 04 00 00 00 e8 66 c7 15 00 48 8b 04 24 f0 ff 40 30 <49> bd 00 00 00 00 00 fc ff df 43 80 3c 2f 00 74 08 4c 89 f7 e8 a5 RSP: 0018:ffffc9000334f4c0 EFLAGS: 00000206 RAX: ffffea0000adabc0 RBX: 000000000000008c RCX: ffffffff81ca7b3a RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffea0000adabf0 RBP: ffffc9000334f870 R08: dffffc0000000000 R09: fffff9400015b57f R10: 0000000000000000 R11: dffffc0000000001 R12: ffffea0000adabc0 R13: ffffea0000adabf4 R14: ffffea0000adabc8 R15: 1ffffd400015b579 dup_mmap kernel/fork.c:696 [inline] dup_mm+0xddf/0x1610 kernel/fork.c:1532 copy_mm+0xca/0x160 kernel/fork.c:1581 copy_process+0x19a2/0x4020 kernel/fork.c:2259 kernel_clone+0x222/0x920 kernel/fork.c:2679 __do_sys_clone kernel/fork.c:2820 [inline] __se_sys_clone kernel/fork.c:2804 [inline] __x64_sys_clone+0x231/0x280 kernel/fork.c:2804 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f8607879b53 Code: 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 89 c2 85 c0 75 2c 64 48 8b 04 25 10 00 00 RSP: 002b:00007ffed4191248 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f8607879b53 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 0000555555c6c750 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000001 rcu: rcu_preempt kthread starved for 10506 jiffies! g129433 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:25856 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x132c/0x4330 kernel/sched/core.c:6554 schedule+0xbf/0x180 kernel/sched/core.c:6630 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1935 rcu_gp_fqs_loop+0x2c2/0x1010 kernel/rcu/tree.c:1661 rcu_gp_kthread+0xa3/0x3a0 kernel/rcu/tree.c:1860 kthread+0x26e/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 PID: 4228 Comm: kworker/u4:15 Not tainted 6.1.38-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:413 [inline] RIP: 0010:smp_call_function_many_cond+0x1f67/0x33d0 kernel/smp.c:987 Code: e6 01 31 ff e8 9a 11 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 0a e8 25 0e 0b 00 e9 1b ff ff ff f3 90 42 0f b6 04 2b <84> c0 75 14 41 f7 07 01 00 00 00 0f 84 fe fe ff ff e8 03 0e 0b 00 RSP: 0018:ffffc90015ecf5a0 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 1ffff1101730841d RCX: ffff888037880000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90015ecf980 R08: ffffffff817ecd06 R09: fffffbfff2052845 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000800000000 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b98420e8 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005555560fe788 CR3: 000000000cc8e000 CR4: 00000000003506e0 Call Trace: on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1155 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1316 [inline] text_poke_bp_batch+0x2bb/0x940 arch/x86/kernel/alternative.c:1516 text_poke_flush arch/x86/kernel/alternative.c:1707 [inline] text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1714 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x12e/0x250 kernel/jump_label.c:177 static_key_enable+0x16/0x20 kernel/jump_label.c:190 toggle_allocation_gate+0xbf/0x480 mm/kfence/core.c:804 process_one_work+0x8aa/0x11f0 kernel/workqueue.c:2289 worker_thread+0xa5f/0x1210 kernel/workqueue.c:2436 kthread+0x26e/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306