rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (0 ticks this GP) idle=87ec/1/0x4000000000000000 softirq=153323/153323 fqs=1 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P1568/3:b..l P29881/1:b..l rcu: (detected by 0, t=10502 jiffies, g=171177, q=282 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 809 Comm: syz-executor Not tainted 6.12.0-syzkaller-10553-gb86545e02e8c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] RIP: 0010:_raw_spin_lock_irqsave+0xbe/0x120 kernel/locking/spinlock.c:162 Code: 4c 89 e7 e8 74 60 29 f6 4c 8b 64 24 20 fa 41 f7 c4 00 02 00 00 74 05 e8 90 6e c9 f5 bf 01 00 00 00 e8 86 b1 8f f5 49 8d 7e 18 <31> f6 31 d2 31 c9 41 b8 01 00 00 00 45 31 c9 ff 75 08 e8 db d9 9c RSP: 0018:ffffc90000a18b80 EFLAGS: 00000006 RAX: 0000000000010004 RBX: 1ffff92000143174 RCX: ffffffff9a3f7903 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff9a6add88 RBP: ffffc90000a18c10 R08: ffffc90000a18c6f R09: 0000000000000000 R10: ffffc90000a18c60 R11: fffff5200014318e R12: 0000000000000046 R13: 1ffff92000143170 R14: ffffffff9a6add70 R15: dffffc0000000000 FS: 0000555564d55500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c25821a CR3: 000000005d58a000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: debug_object_deactivate+0x158/0x390 lib/debugobjects.c:873 debug_hrtimer_deactivate kernel/time/hrtimer.c:433 [inline] debug_deactivate+0x1b/0x220 kernel/time/hrtimer.c:475 __run_hrtimer kernel/time/hrtimer.c:1707 [inline] __hrtimer_run_queues+0x305/0xd50 kernel/time/hrtimer.c:1803 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1865 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0xff/0x550 kernel/locking/lockdep.c:5822 Code: 0f a3 1d 94 15 ac 0e 73 16 e8 2d 60 0a 00 84 c0 75 0d 80 3d 16 4d 96 0e 00 0f 84 f9 02 00 00 48 c7 c0 c0 62 1d 90 48 c1 e8 03 <42> 0f b6 04 28 84 c0 0f 85 ff 02 00 00 83 3d ed 47 ac 0e 00 0f 84 RSP: 0018:ffffc9000d69f040 EFLAGS: 00000a02 RAX: 1ffffffff203ac58 RBX: 0000000000000001 RCX: ffffffff81711a94 RDX: 0000000000000000 RSI: ffffffff8c608380 RDI: ffffffff8c608340 RBP: ffffc9000d69f198 R08: ffffffff901d3037 R09: 1ffffffff203a606 R10: dffffc0000000000 R11: fffffbfff203a607 R12: 1ffff92001ad3e10 R13: dffffc0000000000 R14: 0000000000000000 R15: ffffea0001956c80 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] page_ext_get+0x3d/0x2a0 mm/page_ext.c:525 page_table_check_set+0x4f/0x540 mm/page_table_check.c:114 __page_table_check_ptes_set+0x30f/0x410 mm/page_table_check.c:225 page_table_check_ptes_set include/linux/page_table_check.h:74 [inline] set_ptes include/linux/pgtable.h:288 [inline] __copy_present_ptes mm/memory.c:967 [inline] copy_present_ptes mm/memory.c:1050 [inline] copy_pte_range mm/memory.c:1173 [inline] copy_pmd_range+0x457c/0x7eb0 mm/memory.c:1261 copy_pud_range mm/memory.c:1298 [inline] copy_p4d_range mm/memory.c:1322 [inline] copy_page_range+0x99f/0xe90 mm/memory.c:1420 dup_mmap kernel/fork.c:751 [inline] dup_mm kernel/fork.c:1695 [inline] copy_mm+0x11c7/0x1f90 kernel/fork.c:1744 copy_process+0x1845/0x3d50 kernel/fork.c:2395 kernel_clone+0x223/0x880 kernel/fork.c:2807 __do_sys_clone kernel/fork.c:2950 [inline] __se_sys_clone kernel/fork.c:2934 [inline] __x64_sys_clone+0x258/0x2a0 kernel/fork.c:2934 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: 0033:0x7f7e65577053 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:00007fff6256a508 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7e65577053 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: 0000555564d557d0 R11: 0000000000000246 R12: 0000000000000000 R13: 00000000002bd14e R14: 00000000002bcdfc R15: 00007fff6256a690 task:kworker/u8:4 state:R running task stack:20728 pid:29881 tgid:29881 ppid:2 flags:0x00004000 Workqueue: bat_events batadv_nc_worker Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7078 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:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5853 Code: 2b 00 74 08 4c 89 f7 e8 1a 84 8c 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc9000542f980 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000a85f3c RCX: ffff888060f1c6d8 RDX: dffffc0000000000 RSI: ffffffff8c0aeb60 RDI: ffffffff8c6083a0 RBP: ffffc9000542fad0 R08: ffffffff942f0887 R09: 1ffffffff285e110 R10: dffffc0000000000 R11: fffffbfff285e111 R12: 1ffff92000a85f38 R13: dffffc0000000000 R14: ffffc9000542f9e0 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] batadv_nc_process_nc_paths+0xd6/0x3a0 net/batman-adv/network-coding.c:687 batadv_nc_worker+0x52c/0x610 net/batman-adv/network-coding.c:735 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 task:syz.0.7633 state:R running task stack:25776 pid:1568 tgid:1568 ppid:838 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6935 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6959 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: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 mm/memory.c:3979 [inline] handle_pte_fault+0x31d6/0x68a0 mm/memory.c:5801 __handle_mm_fault mm/memory.c:5944 [inline] handle_mm_fault+0x1053/0x1ad0 mm/memory.c:6112 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: 0033:0x7fb250e5f23d RSP: 002b:00007fff3ff86a50 EFLAGS: 00010202 RAX: 000000110c254000 RBX: 00007fb251c75720 RCX: 0000000000000004 RDX: 0000000000001ea3 RSI: 00000000000021fa RDI: 0000000000000010 RBP: ffffffff84b87ea3 R08: 00007fb251146038 R09: 00007fb251132000 R10: 00007fb2505ff008 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff84b877ae R15: 0000000000000146 rcu: rcu_preempt kthread starved for 10500 jiffies! g171177 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:25016 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/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: 24260 Comm: kworker/u8:18 Not tainted 6.12.0-syzkaller-10553-gb86545e02e8c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:check_kcov_mode kernel/kcov.c:194 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x37/0x70 kernel/kcov.c:217 Code: 80 d4 03 00 65 8b 15 40 f0 6d 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 1c 16 00 00 00 74 2c 8b 91 f8 15 00 00 <83> fa 02 75 21 48 8b 91 00 16 00 00 48 8b 32 48 8d 7e 01 8b 89 fc RSP: 0018:ffffc9000ba8f6d8 EFLAGS: 00000246 RAX: ffffffff8189fe6b RBX: 1ffff110170e88b9 RCX: ffff888051181e00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000ba8f8e0 R08: ffffffff8189fe3a R09: 1ffffffff285e110 R10: dffffc0000000000 R11: fffffbfff285e111 R12: dffffc0000000000 R13: ffff8880b87445c8 R14: ffff8880b863f940 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0caa87c81c CR3: 000000000e738000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000020 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: csd_lock_wait kernel/smp.c:340 [inline] smp_call_function_many_cond+0x1a0b/0x2ca0 kernel/smp.c:884 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:2114 [inline] text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2324 text_poke_flush arch/x86/kernel/alternative.c:2515 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2522 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x136/0x260 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xbc/0x260 mm/kfence/core.c:849 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244