rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P17545/1:b..l P1262/1:b..l rcu: (detected by 0, t=10502 jiffies, g=99513, q=286 ncpus=2) task:kworker/u8:8 state:R running task stack:25200 pid:1262 tgid:1262 ppid:2 flags:0x00004000 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7067 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:batadv_iv_ogm_schedule_buff+0xc45/0x1500 net/batman-adv/bat_iv_ogm.c:843 Code: 85 4f 08 00 00 48 8b 1b 48 81 fb e0 0c ed 94 0f 84 dc 02 00 00 e8 3b d6 e6 f6 48 8d 7b 78 48 89 f8 48 c1 e8 03 42 80 3c 30 00 <0f> 85 0b 08 00 00 41 80 3f 00 48 8b 6b 78 0f 85 07 08 00 00 49 3b RSP: 0018:ffffc90004e4fb60 EFLAGS: 00000246 RAX: 1ffff11002cf930f RBX: ffff8880167c9800 RCX: ffffffff8aa7104f RDX: ffff8880231b1e00 RSI: ffffffff8aa70da5 RDI: ffff8880167c9878 RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000007 R11: ffffffff8b2f2a60 R12: ffff888055250820 R13: ffff888055358000 R14: dffffc0000000000 R15: ffffed100aa6b00f batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:868 [inline] batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:861 [inline] batadv_iv_send_outstanding_bat_ogm_packet+0x31e/0x8d0 net/batman-adv/bat_iv_ogm.c:1712 process_one_work+0x9fb/0x1b60 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3393 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 task:syz-executor.3 state:R running task stack:25712 pid:17545 tgid:17544 ppid:15773 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7067 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+0x1f2/0x560 kernel/locking/lockdep.c:5722 Code: c1 05 3a af 96 7e 83 f8 01 0f 85 ea 02 00 00 9c 58 f6 c4 02 0f 85 d5 02 00 00 48 85 ed 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24 RSP: 0018:ffffc900055eee18 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff92000abddc5 RCX: 00000000d7e3de73 RDX: 0000000000000001 RSI: ffffffff8b2cb260 RDI: ffffffff8b8ff980 RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff284cc58 R10: ffffffff942662c7 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8dbb1920 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:329 [inline] rcu_read_lock include/linux/rcupdate.h:781 [inline] page_ext_get+0x3a/0x310 mm/page_ext.c:521 __set_page_owner+0x96/0x560 mm/page_owner.c:322 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1468 prep_new_page mm/page_alloc.c:1476 [inline] get_page_from_freelist+0x136a/0x2e50 mm/page_alloc.c:3420 __alloc_pages_noprof+0x22b/0x2460 mm/page_alloc.c:4678 alloc_pages_mpol_noprof+0x275/0x610 mm/mempolicy.c:2265 vma_alloc_folio_noprof+0xad/0x1f0 mm/mempolicy.c:2304 folio_prealloc mm/memory.c:1048 [inline] wp_page_copy mm/memory.c:3285 [inline] do_wp_page+0xf51/0x3340 mm/memory.c:3677 handle_pte_fault mm/memory.c:5396 [inline] __handle_mm_fault+0x2311/0x5410 mm/memory.c:5523 handle_mm_fault+0x476/0xa00 mm/memory.c:5688 do_user_addr_fault+0x2e5/0xe50 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:ffffc900055ef958 EFLAGS: 00050206 RAX: 0000000000000001 RBX: 0000000000001000 RCX: 0000000000000e80 RDX: 0000000000000000 RSI: ffff888012e6f180 RDI: 0000000020433000 RBP: 0000000000001000 R08: 0000000000000000 R09: ffffed10025cdfff R10: ffff888012e6ffff R11: 0000000000000000 R12: 0000000000432b80 R13: ffffc900055efd50 R14: ffff888012e6f000 R15: 0000000020432e80 copy_user_generic arch/x86/include/asm/uaccess_64.h:110 [inline] raw_copy_to_user arch/x86/include/asm/uaccess_64.h:131 [inline] copy_to_user_iter lib/iov_iter.c:25 [inline] iterate_iovec include/linux/iov_iter.h:51 [inline] iterate_and_advance2 include/linux/iov_iter.h:247 [inline] iterate_and_advance include/linux/iov_iter.h:271 [inline] _copy_to_iter+0x4d2/0x1140 lib/iov_iter.c:185 copy_page_to_iter lib/iov_iter.c:362 [inline] copy_page_to_iter+0xf1/0x180 lib/iov_iter.c:349 process_vm_rw_pages mm/process_vm_access.c:45 [inline] process_vm_rw_single_vec mm/process_vm_access.c:118 [inline] process_vm_rw_core.constprop.0+0x5c9/0xa10 mm/process_vm_access.c:216 process_vm_rw+0x301/0x360 mm/process_vm_access.c:284 __do_sys_process_vm_readv mm/process_vm_access.c:296 [inline] __se_sys_process_vm_readv mm/process_vm_access.c:292 [inline] __x64_sys_process_vm_readv+0xe2/0x1c0 mm/process_vm_access.c:292 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: 0033:0x7f090427d0a9 RSP: 002b:00007f0904fbe0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000136 RAX: ffffffffffffffda RBX: 00007f09043b3f80 RCX: 00007f090427d0a9 RDX: 0000000000000002 RSI: 0000000020008400 RDI: 00000000000000a7 RBP: 00007f09042ec074 R08: 0000000000000286 R09: 0000000000000000 R10: 0000000020008640 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f09043b3f80 R15: 00007ffc13b12448 rcu: rcu_preempt kthread starved for 10136 jiffies! g99513 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:27680 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6837 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2000 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2202 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: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:112