rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=a214/1/0x4000000000000000 softirq=33435/33436 fqs=0 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P9996/3:b..l P9965/2:b..l rcu: (detected by 1, t=10502 jiffies, g=24297, q=36287 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 9993 Comm: syz.4.995 Not tainted 6.13.0-rc4-syzkaller-00078-g059dd502b263 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:write_comp_data+0x0/0x90 kernel/kcov.c:240 Code: 48 83 c0 01 48 39 d0 73 07 48 89 01 48 89 34 c1 c3 cc cc cc cc 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <49> 89 d2 49 89 f8 49 89 f1 65 48 8b 15 bf c2 69 7e 65 8b 05 c0 c2 RSP: 0018:ffffc90000007db8 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffff88802822d340 RCX: ffffffff8b260b48 RDX: ffff88802822d340 RSI: ffff88802822d340 RDI: 0000000000000006 RBP: ffff88802822d340 R08: 0000000000000005 R09: 000000000000001f R10: 0000000000000003 R11: 0000000000000002 R12: ffff8880b862ca00 R13: 0000000000000008 R14: ffff8880b862ca00 R15: ffffffff89415480 FS: 00007f7d8366f6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c3c6180 CR3: 000000005a04c000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: timerqueue_add+0x48/0x330 lib/timerqueue.c:38 enqueue_hrtimer+0x1c9/0x3c0 kernel/time/hrtimer.c:1084 __run_hrtimer kernel/time/hrtimer.c:1756 [inline] __hrtimer_run_queues+0x903/0xae0 kernel/time/hrtimer.c:1803 hrtimer_interrupt+0x392/0x8e0 kernel/time/hrtimer.c:1865 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x10f/0x400 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194 Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 a6 72 4a f6 48 89 df e8 ee f1 4a f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 e5 d6 3b f6 65 8b 05 a6 92 d7 74 85 c0 74 16 5b RSP: 0018:ffffc900040ef818 EFLAGS: 00000246 RAX: 0000000000000002 RBX: ffff88807dc4a800 RCX: 1ffffffff2dd39c4 RDX: 0000000000000000 RSI: ffffffff8b6cd9e0 RDI: ffffffff8bd1eda0 RBP: 0000000000000286 R08: 0000000000000001 R09: fffffbfff2dca3af R10: ffffffff96e51d7f R11: 0000000000000004 R12: 0000000000000002 R13: ffff88807dc4a840 R14: ffff88807dc4a1e8 R15: ffff88807dc4a668 __unix_dgram_recvmsg+0x32a/0xe50 net/unix/af_unix.c:2463 unix_dgram_recvmsg+0xd0/0x110 net/unix/af_unix.c:2538 sock_recvmsg_nosec net/socket.c:1033 [inline] ____sys_recvmsg+0x5f8/0x6b0 net/socket.c:2801 ___sys_recvmsg+0x115/0x1a0 net/socket.c:2845 do_recvmmsg+0x2f8/0x740 net/socket.c:2940 __sys_recvmmsg net/socket.c:3014 [inline] __do_sys_recvmmsg net/socket.c:3037 [inline] __se_sys_recvmmsg net/socket.c:3030 [inline] __x64_sys_recvmmsg+0x239/0x290 net/socket.c:3030 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7d82785d29 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f7d8366f038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007f7d82976080 RCX: 00007f7d82785d29 RDX: 0000000000010106 RSI: 00000000200000c0 RDI: 0000000000000003 RBP: 00007f7d82801b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f7d82976080 R15: 00007ffce334fe78 task:syz.3.991 state:R running task stack:25664 pid:9965 tgid:9964 ppid:5815 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7078 irqentry_exit+0x36/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire.part.0+0x155/0x380 kernel/locking/lockdep.c:5814 Code: b8 ff ff ff ff 65 0f c1 05 30 c2 8b 7e 83 f8 01 0f 85 d0 01 00 00 9c 58 f6 c4 02 0f 85 e5 01 00 00 48 85 ed 0f 85 b6 01 00 00 <48> b8 00 00 00 00 00 fc ff df 48 01 c3 48 c7 03 00 00 00 00 48 c7 RSP: 0018:ffffc90002ff71d8 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 1ffff920005fee3c RCX: 00000000ae5441a4 RDX: 0000000000000001 RSI: ffffffff8b6cdce0 RDI: ffffffff8bd1eda0 RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff2dca398 R10: ffffffff96e51cc7 R11: 0000000000000003 R12: 0000000000000000 R13: ffffffff8e1bb900 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] filemap_map_pages+0x188/0x16b0 mm/filemap.c:3645 do_fault_around mm/memory.c:5280 [inline] do_read_fault mm/memory.c:5313 [inline] do_fault mm/memory.c:5456 [inline] do_pte_missing+0xda6/0x3e00 mm/memory.c:3979 handle_pte_fault mm/memory.c:5801 [inline] __handle_mm_fault+0x103c/0x2a40 mm/memory.c:5944 handle_mm_fault+0x3fa/0xaa0 mm/memory.c:6112 do_user_addr_fault+0x7a3/0x13f0 arch/x86/mm/fault.c:1389 handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0010:rep_movs_alternative+0x4a/0x70 arch/x86/lib/copy_user_64.S:71 Code: 75 f1 c3 cc cc cc cc 66 0f 1f 84 00 00 00 00 00 48 8b 06 48 89 07 48 83 c6 08 48 83 c7 08 83 e9 08 74 df 83 f9 08 73 e8 eb c9 a4 c3 cc cc cc cc 48 89 c8 48 c1 e9 03 83 e0 07 f3 48 a5 89 c1 RSP: 0018:ffffc90002ff7858 EFLAGS: 00050202 RAX: 0000000000000001 RBX: 0000000000007fd8 RCX: 0000000000003ac8 RDX: 0000000000000000 RSI: 0000000020114000 RDI: ffff888058ef4538 RBP: 000000002010faf0 R08: 0000000000000001 R09: ffffed100b1defff R10: ffff888058ef7fff R11: 0000000000000000 R12: ffffc90002ff7e58 R13: 0000000020117ac8 R14: ffff888058ef0028 R15: 00007ffffffff000 copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline] raw_copy_from_user arch/x86/include/asm/uaccess_64.h:141 [inline] copy_from_user_iter lib/iov_iter.c:55 [inline] iterate_ubuf include/linux/iov_iter.h:30 [inline] iterate_and_advance2 include/linux/iov_iter.h:300 [inline] iterate_and_advance include/linux/iov_iter.h:328 [inline] __copy_from_iter lib/iov_iter.c:249 [inline] _copy_from_iter+0x385/0x1560 lib/iov_iter.c:260 copy_from_iter include/linux/uio.h:219 [inline] copy_from_iter_full include/linux/uio.h:236 [inline] do_copy_data_nocache net/mptcp/protocol.c:1783 [inline] mptcp_sendmsg+0x1010/0x1f20 net/mptcp/protocol.c:1890 inet_sendmsg+0x119/0x140 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg net/socket.c:726 [inline] ____sys_sendmsg+0x98c/0xc90 net/socket.c:2583 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2637 __sys_sendmsg+0x16e/0x220 net/socket.c:2669 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1bf7d85d29 RSP: 002b:00007f1bf8c7e038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f1bf7f75fa0 RCX: 00007f1bf7d85d29 RDX: 0000000000004000 RSI: 0000000020000100 RDI: 0000000000000006 RBP: 00007f1bf7e01b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f1bf7f75fa0 R15: 00007ffc29a9d4b8 task:dhcpcd-run-hook state:R running task stack:28432 pid:9996 tgid:9996 ppid:9992 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6935 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+0xe4e/0x16b0 mm/filemap.c:3689 do_fault_around mm/memory.c:5280 [inline] do_read_fault mm/memory.c:5313 [inline] do_fault mm/memory.c:5456 [inline] do_pte_missing+0xda6/0x3e00 mm/memory.c:3979 handle_pte_fault mm/memory.c:5801 [inline] __handle_mm_fault+0x103c/0x2a40 mm/memory.c:5944 handle_mm_fault+0x3fa/0xaa0 mm/memory.c:6112 do_user_addr_fault+0x60d/0x13f0 arch/x86/mm/fault.c:1338 handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7fca1f1a25eb RSP: 002b:00007ffd10aaea68 EFLAGS: 00010202 RAX: 0000558b8d0b0ee0 RBX: 0000558b8d0ab218 RCX: 00007ffd10aaeab8 RDX: 0000000000000000 RSI: 0000558b8d0b0cd8 RDI: 0000558b8d0ab460 RBP: 0000558b8d0b0cd8 R08: 0000558b8d0b0ee0 R09: 0000000000000000 R10: 000000000000003f R11: 0000000000000000 R12: 0000558b8d0ab460 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 10502 jiffies! g24297 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:27488 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6848 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2045 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2247 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 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: 1 UID: 0 PID: 6596 Comm: kworker/u8:12 Not tainted 6.13.0-rc4-syzkaller-00078-g059dd502b263 #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+0x45d/0x1300 kernel/smp.c:884 Code: 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 f4 4c 89 f5 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 ba 0e 0c 00 f3 90 41 0f b6 04 24 <40> 38 c5 7c 08 84 c0 0f 85 a7 0c 00 00 8b 43 08 31 ff 83 e0 01 41 RSP: 0018:ffffc900052cf998 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b86469c0 RCX: ffffffff818e071c RDX: ffff88802a438000 RSI: ffffffff818e06f6 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000006 R12: ffffed10170c8d39 R13: 0000000000000001 R14: ffff8880b86469c8 R15: ffff8880b873fe40 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2f4fdff8 CR3: 000000000df7e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1051 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2114 [inline] text_poke_bp_batch+0x22b/0x760 arch/x86/kernel/alternative.c:2324 text_poke_flush arch/x86/kernel/alternative.c:2515 [inline] text_poke_flush arch/x86/kernel/alternative.c:2512 [inline] text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2522 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x1d7/0x400 kernel/jump_label.c:920 static_key_enable_cpuslocked+0x1b7/0x270 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate mm/kfence/core.c:849 [inline] toggle_allocation_gate+0xfc/0x260 mm/kfence/core.c:841 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244