rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P13578/1:b..l P13583/3:b..l P13570/1:b..l rcu: (detected by 0, t=10502 jiffies, g=59857, q=618 ncpus=2) task:syz.6.1983 state:R running task stack:24560 pid:13570 tgid:13569 ppid:9229 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x184f/0x4c30 kernel/sched/core.c:6690 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6869 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6893 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] zap_pte_range mm/memory.c:1691 [inline] zap_pmd_range mm/memory.c:1739 [inline] zap_pud_range mm/memory.c:1768 [inline] zap_p4d_range mm/memory.c:1789 [inline] unmap_page_range+0x36b1/0x40e0 mm/memory.c:1810 unmap_vmas+0x3cc/0x5f0 mm/memory.c:1900 exit_mmap+0x275/0xc40 mm/mmap.c:1913 __mmput+0x115/0x390 kernel/fork.c:1348 exit_mm+0x220/0x310 kernel/exit.c:571 do_exit+0x9b2/0x28e0 kernel/exit.c:926 do_group_exit+0x207/0x2c0 kernel/exit.c:1088 get_signal+0x16a3/0x1740 kernel/signal.c:2917 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7e20f7e7a7 RSP: 002b:00007f7e21cbde18 EFLAGS: 00000286 ORIG_RAX: 000000000000000b RAX: 0000000000000000 RBX: 0000000000020000 RCX: 00007f7e20f7e7a7 RDX: 0000000000000000 RSI: 0000000008400000 RDI: 00007f7e16e00000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000001512 R10: 0000000000001ffc R11: 0000000000000286 R12: 0000000000000007 R13: 00007f7e21cbdef0 R14: 00007f7e21cbdeb0 R15: 00007f7e16e00000 task:dhcpcd state:R running task stack:25360 pid:13583 tgid:13583 ppid:5503 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x184f/0x4c30 kernel/sched/core.c:6690 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6869 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6893 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] filemap_map_pages+0x1759/0x20d0 mm/filemap.c:3688 do_fault_around mm/memory.c:5255 [inline] do_read_fault mm/memory.c:5288 [inline] do_fault mm/memory.c:5431 [inline] do_pte_missing mm/memory.c:3965 [inline] handle_pte_fault+0x2b9a/0x6820 mm/memory.c:5766 __handle_mm_fault mm/memory.c:5909 [inline] handle_mm_fault+0x1106/0x1bb0 mm/memory.c:6077 do_user_addr_fault arch/x86/mm/fault.c:1338 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x459/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f8120bd601e RSP: 002b:00007fff95e96b78 EFLAGS: 00010202 RAX: 0000000000000000 RBX: 0000000000000100 RCX: 0000000000000000 RDX: 00007fff95e96d08 RSI: 0000562741feca4d RDI: 00007fff95e96b90 RBP: 00007fff95e96df8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000246 R12: 00007fff95e96b90 R13: 0000562741feca4d R14: 00007fff95e96d08 R15: 00007fff95e96c80 task:syz.4.1988 state:R running task stack:25008 pid:13578 tgid:13577 ppid:12852 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x184f/0x4c30 kernel/sched/core.c:6690 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7012 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:rcu_read_unlock include/linux/rcupdate.h:878 [inline] RIP: 0010:is_bpf_text_address+0x1ff/0x2a0 kernel/bpf/core.c:769 Code: 0c 39 c8 74 0a e8 a1 f3 f0 ff e9 ea fe ff ff e8 b7 57 23 0a 89 c3 31 ff 89 c6 e8 cc f7 f0 ff 85 db 74 10 e8 d3 e0 d6 ff 84 c0 <74> 0e e8 7a f3 f0 ff eb 56 e8 73 f3 f0 ff eb 4f e8 8c 57 23 0a 89 RSP: 0018:ffffc9000b36ee28 EFLAGS: 00000202 RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffff8880345ebc00 RDX: ffff8880345ebc00 RSI: ffffffff8c610840 RDI: ffffffff8c610800 RBP: 0000000000000000 R08: ffffffff81a3e6d4 R09: 1ffffffff2859b00 R10: dffffc0000000000 R11: fffffbfff2859b01 R12: ffffffffa0000830 R13: dffffc0000000000 R14: 0000000000000000 R15: 00007f616657e719 kernel_text_address+0xa7/0xe0 kernel/extable.c:125 __kernel_text_address+0xd/0x40 kernel/extable.c:79 unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:369 arch_stack_walk+0xfd/0x150 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:257 [inline] __do_kmalloc_node mm/slub.c:4264 [inline] __kmalloc_node_track_caller_noprof+0x225/0x440 mm/slub.c:4283 kmalloc_reserve+0x111/0x2a0 net/core/skbuff.c:609 __alloc_skb+0x1f3/0x440 net/core/skbuff.c:678 alloc_skb include/linux/skbuff.h:1322 [inline] alloc_skb_with_frags+0xc3/0x820 net/core/skbuff.c:6612 sock_alloc_send_pskb+0x91a/0xa60 net/core/sock.c:2883 unix_dgram_sendmsg+0x6d3/0x1f80 net/unix/af_unix.c:2027 sock_sendmsg_nosec net/socket.c:729 [inline] __sock_sendmsg+0x223/0x270 net/socket.c:744 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2607 ___sys_sendmsg net/socket.c:2661 [inline] __sys_sendmmsg+0x3ab/0x730 net/socket.c:2747 __do_sys_sendmmsg net/socket.c:2776 [inline] __se_sys_sendmmsg net/socket.c:2773 [inline] __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2773 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f616657e719 RSP: 002b:00007f6167338038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f6166735f80 RCX: 00007f616657e719 RDX: 0000000000000318 RSI: 00000000200bd000 RDI: 0000000000000004 RBP: 00007f61665f139e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f6166735f80 R15: 00007ffe5d051e78 rcu: rcu_preempt kthread starved for 10494 jiffies! g59857 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:24656 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x184f/0x4c30 kernel/sched/core.c:6690 __schedule_loop kernel/sched/core.c:6767 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6782 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2615 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 UID: 0 PID: 12 Comm: kworker/u8:1 Not tainted 6.12.0-rc6-syzkaller-00077-g2e1b3cc9d7f7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x19f3/0x2ca0 kernel/smp.c:884 Code: 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 86 f3 0b 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 31 ef 0b 00 eb 38 f3 90 <42> 0f b6 04 23 84 c0 75 11 41 f7 45 00 01 00 00 00 74 1e e8 15 ef RSP: 0018:ffffc900001176e0 EFLAGS: 00000293 RAX: ffffffff8188eb4b RBX: 1ffff110170e8919 RCX: ffff88801c2ada00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900001178e0 R08: ffffffff8188eb1a R09: 1ffffffff2859b00 R10: dffffc0000000000 R11: fffffbfff2859b01 R12: dffffc0000000000 R13: ffff8880b87448c8 R14: ffff8880b863fc80 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000562742003028 CR3: 000000000e734000 CR4: 0000000000350ef0 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1051 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2085 [inline] text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2295 text_poke_flush arch/x86/kernel/alternative.c:2486 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2493 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_disable_cpuslocked+0xd2/0x1c0 kernel/jump_label.c:240 static_key_disable+0x1a/0x20 kernel/jump_label.c:248 toggle_allocation_gate+0x1bf/0x260 mm/kfence/core.c:854 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244