rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7780/3:b..l rcu: (detected by 0, t=10504 jiffies, g=15689, q=183 ncpus=2) task:syz.4.412 state:R running task stack:27416 pid:7780 tgid:7780 ppid:5818 task_flags:0x400040 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6947 preempt_schedule_thunk+0x16/0x30 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+0xe2b/0x1680 mm/filemap.c:3747 do_fault_around mm/memory.c:5476 [inline] do_read_fault mm/memory.c:5509 [inline] do_fault mm/memory.c:5652 [inline] do_pte_missing+0xf1a/0x3fb0 mm/memory.c:4160 handle_pte_fault mm/memory.c:5997 [inline] __handle_mm_fault+0x103d/0x2a40 mm/memory.c:6140 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6309 do_user_addr_fault+0x60c/0x1370 arch/x86/mm/fault.c:1337 handle_page_fault arch/x86/mm/fault.c:1480 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1538 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f6ff7a6d4cd RSP: 002b:00007ffedb86b1c0 EFLAGS: 00010246 RAX: 000000110c384000 RBX: 00007f6ff88d5720 RCX: 0000000000000000 RDX: 0000000000001d06 RSI: 0000000000000574 RDI: 0000000000000001 RBP: ffffffff8b715d06 R08: 00007f6ff7da6038 R09: 00007f6ff7d92000 R10: 00007f6ff71ff008 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8b71593d R15: 000000000000010f rcu: rcu_preempt kthread starved for 10504 jiffies! g15689 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:27688 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2046 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2248 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 UID: 0 PID: 61 Comm: kworker/u8:4 Not tainted 6.14.0-syzkaller-12456-gacc4d5ff0b61 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:write_comp_data+0x42/0x90 kernel/kcov.c:246 Code: a9 00 01 ff 00 74 1d f6 c4 01 74 67 a9 00 00 0f 00 75 60 a9 00 00 f0 00 75 59 8b 82 3c 16 00 00 85 c0 74 4f 8b 82 18 16 00 00 <83> f8 03 75 44 48 8b 82 20 16 00 00 8b 92 1c 16 00 00 48 8b 38 48 RSP: 0018:ffffc9000214f930 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff8880b853f740 RCX: ffffffff81af2959 RDX: ffff88801c3fc880 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffed10170a7ee9 R13: 0000000000000001 R14: dffffc0000000000 R15: ffff8880b843b040 FS: 0000000000000000(0000) GS:ffff8881249bb000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2f709ff8 CR3: 000000000e182000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: csd_lock_wait kernel/smp.c:340 [inline] smp_call_function_many_cond+0x4c9/0x1290 kernel/smp.c:885 on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1052 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2455 [inline] text_poke_bp_batch+0x220/0x760 arch/x86/kernel/alternative.c:2665 text_poke_flush arch/x86/kernel/alternative.c:2856 [inline] text_poke_flush arch/x86/kernel/alternative.c:2853 [inline] text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2863 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x376/0x550 kernel/jump_label.c:919 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:850 [inline] toggle_allocation_gate+0xfa/0x280 mm/kfence/core.c:842 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 watchdog: BUG: soft lockup - CPU#0 stuck for 245s! [kworker/u8:4:61] Modules linked in: irq event stamp: 22344530 hardirqs last enabled at (22344529): [] irqentry_exit+0x3b/0x90 kernel/entry/common.c:357 hardirqs last disabled at (22344530): [] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1049 softirqs last enabled at (22344528): [] softirq_handle_end kernel/softirq.c:425 [inline] softirqs last enabled at (22344528): [] handle_softirqs+0x5be/0x8e0 kernel/softirq.c:607 softirqs last disabled at (22344519): [] __do_softirq kernel/softirq.c:613 [inline] softirqs last disabled at (22344519): [] invoke_softirq kernel/softirq.c:453 [inline] softirqs last disabled at (22344519): [] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:680 CPU: 0 UID: 0 PID: 61 Comm: kworker/u8:4 Not tainted 6.14.0-syzkaller-12456-gacc4d5ff0b61 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x4b7/0x1290 kernel/smp.c:885 Code: c4 83 e0 07 49 c1 ec 03 48 89 c5 4d 01 f4 83 c5 03 e8 2d 17 0c 00 f3 90 41 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 de 0b 00 00 <8b> 43 08 31 ff 83 e0 01 41 89 c5 89 c6 e8 47 12 0c 00 45 85 ed 75 RSP: 0018:ffffc9000214f938 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff8880b853f740 RCX: ffffffff81af2959 RDX: ffff88801c3fc880 RSI: ffffffff81af2933 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffed10170a7ee9 R13: 0000000000000001 R14: dffffc0000000000 R15: ffff8880b843b040 FS: 0000000000000000(0000) GS:ffff8881249bb000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2f709ff8 CR3: 000000000e182000 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:1052 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2455 [inline] text_poke_bp_batch+0x220/0x760 arch/x86/kernel/alternative.c:2665 text_poke_flush arch/x86/kernel/alternative.c:2856 [inline] text_poke_flush arch/x86/kernel/alternative.c:2853 [inline] text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2863 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x376/0x550 kernel/jump_label.c:919 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:850 [inline] toggle_allocation_gate+0xfa/0x280 mm/kfence/core.c:842 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 7784 Comm: syz.1.413 Not tainted 6.14.0-syzkaller-12456-gacc4d5ff0b61 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:validate_chain kernel/locking/lockdep.c:3876 [inline] RIP: 0010:__lock_acquire+0x638/0x1ba0 kernel/locking/lockdep.c:5235 Code: 29 c8 01 d1 c1 c6 10 89 cf 31 f0 89 c6 29 c2 01 c8 c1 ce 0d 31 d6 89 f2 29 f7 01 f0 c1 c2 04 89 c0 31 fa 48 c1 e2 20 48 09 c2 <8b> 43 20 49 89 d0 25 00 80 04 00 3d 00 00 04 00 0f 84 4a 04 00 00 RSP: 0018:ffffc90000a08c38 EFLAGS: 00000082 RAX: 00000000f5214f40 RBX: ffff888075428b68 RCX: 00000000fcfd10eb RDX: cf53885ef5214f40 RSI: 00000000dd0a1718 RDI: 000000001ff2f9d3 RBP: ffff888075428af0 R08: 0000000000080000 R09: 0000000000000001 R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000bda R13: 0000000000000003 R14: ffff888075428000 R15: 0000000000000000 FS: 00007fa5cb63a6c0(0000) GS:ffff888124abb000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000001180 CR3: 000000005530e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire kernel/locking/lockdep.c:5866 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5823 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] advance_sched+0xd9/0xc80 net/sched/sch_taprio.c:924 __run_hrtimer kernel/time/hrtimer.c:1791 [inline] __hrtimer_run_queues+0x1ff/0xad0 kernel/time/hrtimer.c:1855 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1917 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x108/0x3f0 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:console_flush_all+0x9a2/0xc60 kernel/printk/printk.c:3227 Code: 00 e8 e2 17 28 00 9c 5b 81 e3 00 02 00 00 31 ff 48 89 de e8 a0 4b 20 00 48 85 db 0f 85 55 01 00 00 e8 22 50 20 00 fb 4c 89 e0 <48> c1 e8 03 42 80 3c 38 00 0f 84 11 ff ff ff 4c 89 e7 e8 07 b6 85 RSP: 0018:ffffc9001c28ef50 EFLAGS: 00000283 RAX: ffffffff8f0c7a78 RBX: 0000000000000000 RCX: ffffc90004912000 RDX: 0000000000080000 RSI: ffffffff819af03e RDI: 0000000000000007 RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff8f0c7a78 R13: ffffffff8f0c7a20 R14: ffffc9001c28efe0 R15: dffffc0000000000 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0xd8/0x210 kernel/printk/printk.c:3325 vprintk_emit+0x418/0x6d0 kernel/printk/printk.c:2450 _printk+0xc7/0x100 kernel/printk/printk.c:2475 __nla_validate_parse+0x751/0x2880 lib/nlattr.c:647 __nla_parse+0x40/0x60 lib/nlattr.c:732 nla_parse_nested_deprecated include/net/netlink.h:1343 [inline] rtnl_newlink+0x1063/0x2000 net/core/rtnetlink.c:4012 rtnetlink_rcv_msg+0x95b/0xe90 net/core/rtnetlink.c:6955 netlink_rcv_skb+0x16a/0x440 net/netlink/af_netlink.c:2534 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x53a/0x7f0 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg net/socket.c:727 [inline] ____sys_sendmsg+0xa95/0xc70 net/socket.c:2566 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2620 __sys_sendmsg+0x16d/0x220 net/socket.c:2652 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa5ca78d169 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:00007fa5cb63a038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fa5ca9a5fa0 RCX: 00007fa5ca78d169 RDX: 0000000000000000 RSI: 0000200000000280 RDI: 0000000000000003 RBP: 00007fa5ca80e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fa5ca9a5fa0 R15: 00007fff9d7f5598