rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P23039/1:b..l P24524/1:b..l rcu: (detected by 1, t=10502 jiffies, g=327845, q=484 ncpus=2) task:syz-executor state:R running task stack:23680 pid:24524 tgid:24524 ppid:5214 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6851 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_is_held_type+0x13b/0x190 Code: 75 44 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 4c 41 f7 c4 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 42 89 d8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f RSP: 0018:ffffc900036ff788 EFLAGS: 00000206 RAX: c674ae1f493e7700 RBX: 0000000000000001 RCX: 0000000080000000 RDX: 0000000000000000 RSI: ffffffff8c0ae6e0 RDI: ffffffff8c606d80 RBP: 0000000000000000 R08: ffffffff820603ae R09: 1ffffffff26e6908 R10: dffffc0000000000 R11: fffffbfff26e6909 R12: 0000000000000246 R13: ffff88802b4b3c00 R14: 00000000ffffffff R15: ffffffff8e938320 lookup_page_ext mm/page_ext.c:254 [inline] page_ext_get+0x192/0x2a0 mm/page_ext.c:526 __page_table_check_zero+0xb1/0x350 mm/page_table_check.c:148 page_table_check_alloc include/linux/page_table_check.h:33 [inline] post_alloc_hook+0x206/0x230 mm/page_alloc.c:1494 prep_new_page mm/page_alloc.c:1501 [inline] get_page_from_freelist+0x2e4c/0x2f10 mm/page_alloc.c:3439 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4695 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2263 vm_area_alloc_pages mm/vmalloc.c:3584 [inline] __vmalloc_area_node mm/vmalloc.c:3653 [inline] __vmalloc_node_range_noprof+0xa40/0x1400 mm/vmalloc.c:3834 vmalloc_user_noprof+0x74/0x80 mm/vmalloc.c:3988 kcov_ioctl+0x59/0x640 kernel/kcov.c:715 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfe/0x170 fs/ioctl.c:893 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: 0033:0x7ff3b8f79a7b RSP: 002b:00007ffd2ce74270 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000040000 RCX: 00007ff3b8f79a7b RDX: 0000000000040000 RSI: ffffffff80086301 RDI: 00000000000000e0 RBP: 00007ff3b91166d8 R08: 00000000000000da R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000 task:kworker/u8:3 state:R running task stack:23480 pid:23039 tgid:23039 ppid:2 flags:0x00004000 Workqueue: bat_events batadv_nc_worker Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6851 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:5763 Code: 2b 00 74 08 4c 89 f7 e8 0a 00 8b 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:ffffc900045079e0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920008a0f48 RCX: ae9552fbb7f34c00 RDX: dffffc0000000000 RSI: ffffffff8c0ae6e0 RDI: ffffffff8c606d80 RBP: ffffc90004507b40 R08: ffffffff93734847 R09: 1ffffffff26e6908 R10: dffffc0000000000 R11: fffffbfff26e6909 R12: 1ffff920008a0f44 R13: dffffc0000000000 R14: ffffc90004507a40 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:326 [inline] rcu_read_lock include/linux/rcupdate.h:838 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xec/0x610 net/batman-adv/network-coding.c:719 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2e/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd10 kernel/workqueue.c:3389 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: rcu_preempt kthread starved for 10568 jiffies! g327845 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:26448 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2034 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2236 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: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.11.0-rc4-syzkaller-00255-gd2bafcf224f3 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline] RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:92 [inline] RIP: 0010:acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:112 Code: 90 90 90 90 90 90 90 90 90 65 48 8b 04 25 00 d7 03 00 48 f7 00 08 00 00 00 75 10 eb 07 0f 00 2d 85 21 b3 00 f3 0f 1e fa fb f4 e9 c4 3f 39 00 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 RSP: 0018:ffffc900001a7d08 EFLAGS: 00000246 RAX: ffff8880182f0000 RBX: ffff88801bacf064 RCX: 0000000003e842a9 RDX: 0000000000000001 RSI: ffff88801bacf000 RDI: ffff88801bacf064 RBP: 000000000003a678 R08: ffff8880b9337c7b R09: 1ffff11017266f8f R10: dffffc0000000000 R11: ffffffff8bb6fcf0 R12: ffff88801cbe8000 R13: 0000000000000000 R14: 0000000000000001 R15: ffffffff8f0dece0 FS: 0000000000000000(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002002b000 CR3: 000000001dbc4000 CR4: 0000000000350ef0 Call Trace: acpi_idle_enter+0xe4/0x140 drivers/acpi/processor_idle.c:702 cpuidle_enter_state+0x114/0x480 drivers/cpuidle/cpuidle.c:267 cpuidle_enter+0x5d/0xa0 drivers/cpuidle/cpuidle.c:388 call_cpuidle kernel/sched/idle.c:155 [inline] cpuidle_idle_call kernel/sched/idle.c:230 [inline] do_idle+0x375/0x5d0 kernel/sched/idle.c:326 cpu_startup_entry+0x42/0x60 kernel/sched/idle.c:424 start_secondary+0x100/0x100 arch/x86/kernel/smpboot.c:313 common_startup_64+0x13e/0x147