rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P15537/3:b..l rcu: (detected by 0, t=10505 jiffies, g=48181, q=1173 ncpus=2) task:rm state:R running task stack:25512 pid:15537 tgid:15537 ppid:15490 task_flags:0x400000 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5397 [inline] __schedule+0x116a/0x5dd0 kernel/sched/core.c:6786 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6966 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+0xe2e/0x1680 mm/filemap.c:3757 do_fault_around mm/memory.c:5548 [inline] do_read_fault mm/memory.c:5581 [inline] do_fault mm/memory.c:5724 [inline] do_pte_missing mm/memory.c:4251 [inline] handle_pte_fault mm/memory.c:6069 [inline] __handle_mm_fault+0x3b38/0x5490 mm/memory.c:6212 handle_mm_fault+0x589/0xd10 mm/memory.c:6381 do_user_addr_fault+0x60c/0x1370 arch/x86/mm/fault.c:1336 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x5c/0xb0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f0ff2f10dde RSP: 002b:00007ffe796ff9d8 EFLAGS: 00010283 RAX: 00000000fffffee0 RBX: 000056519fe05000 RCX: 00000000000003f0 RDX: 0000000000000000 RSI: 00007f0ff30293f0 RDI: 00007ffe796ffe60 RBP: 00007ffe796ffb28 R08: 0000000000000000 R09: 00007f0ff3060a60 R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe796ffb48 R14: 00007f0ff3091000 R15: 000056519fe06d98 rcu: rcu_preempt kthread timer wakeup didn't happen for 10496 jiffies! g48181 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=72641 rcu: rcu_preempt kthread starved for 10497 jiffies! g48181 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27784 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5397 [inline] __schedule+0x116a/0x5dd0 kernel/sched/core.c:6786 __schedule_loop kernel/sched/core.c:6864 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6879 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2054 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2256 kthread+0x3c5/0x780 kernel/kthread.c:464 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 15528 Comm: syz.1.2059 Not tainted 6.16.0-rc7-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:advance_sched+0x72d/0xc80 net/sched/sch_taprio.c:929 Code: 41 5d 41 5e 41 5f e9 82 1d f0 01 e8 8d 92 22 f8 48 8d 7b c0 be ff ff ff ff e8 7f 2a ed 01 31 ff 41 89 c4 89 c6 e8 b3 8d 22 f8 <45> 85 e4 0f 85 4b fa ff ff e8 65 92 22 f8 e8 c0 2b ed 01 31 ff 41 RSP: 0018:ffffc90000a08d90 EFLAGS: 00000046 RAX: 0000000080010001 RBX: ffff888022eac340 RCX: ffffffff899955fd RDX: ffff888031baa440 RSI: 0000000000000000 RDI: 0000000000000005 RBP: ffff888057c75400 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000001 R13: 0000000000000000 R14: ffff888022eac340 R15: ffffffff89994ed0 FS: 00007f461ffd56c0(0000) GS:ffff888124820000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000059030 CR3: 0000000043877000 CR4: 00000000003526f0 Call Trace: __run_hrtimer kernel/time/hrtimer.c:1761 [inline] __hrtimer_run_queues+0x1ff/0xad0 kernel/time/hrtimer.c:1825 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline] __sysvec_apic_timer_interrupt+0x10b/0x3f0 arch/x86/kernel/apic/apic.c:1056 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5875 Code: 76 37 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 32 b6 10 0f 0f 82 74 02 00 00 8b 35 1a e8 10 0f 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 c9 75 37 12 0f 85 c7 02 00 00 48 83 c4 RSP: 0018:ffffc9001bec6e98 EFLAGS: 00000206 RAX: 0000000000000046 RBX: ffffffff8e5c4e00 RCX: 000000009ccb6cf7 RDX: 0000000000000000 RSI: ffffffff8de0aca5 RDI: ffffffff8c1573e0 RBP: 0000000000000002 R08: 9db3e1ba819abd31 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] __update_page_owner_handle+0x75/0x550 mm/page_owner.c:243 __set_page_owner+0x126/0x550 mm/page_owner.c:330 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1704 prep_new_page mm/page_alloc.c:1712 [inline] get_page_from_freelist+0x1321/0x3890 mm/page_alloc.c:3669 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:4959 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2419 folio_alloc_mpol_noprof+0x36/0x2f0 mm/mempolicy.c:2438 vma_alloc_folio_noprof+0xed/0x1e0 mm/mempolicy.c:2473 folio_prealloc mm/memory.c:1066 [inline] wp_page_copy mm/memory.c:3569 [inline] do_wp_page+0x1136/0x4f20 mm/memory.c:4030 handle_pte_fault mm/memory.c:6085 [inline] __handle_mm_fault+0x2223/0x5490 mm/memory.c:6212 handle_mm_fault+0x589/0xd10 mm/memory.c:6381 do_user_addr_fault+0x7a6/0x1370 arch/x86/mm/fault.c:1387 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x5c/0xb0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0010:__put_user_nocheck_4+0x3/0x10 arch/x86/lib/putuser.S:104 Code: d9 0f 01 cb 89 01 31 c9 0f 01 ca c3 cc cc cc cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 01 cb <89> 01 31 c9 0f 01 ca e9 11 5b 03 00 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc9001bec79f8 EFLAGS: 00050246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000200000059030 RDX: 0000000000080000 RSI: ffffffff8954ce73 RDI: 0000000000000005 RBP: ffffc9001bec7d98 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000000 R12: 0000000000000000 R13: 0000200000059000 R14: ffffc9001bec7ddc R15: 0000000000000002 ____sys_recvmsg+0x2ee/0x6b0 net/socket.c:2799 ___sys_recvmsg+0x114/0x1a0 net/socket.c:2828 do_recvmmsg+0x2fe/0x750 net/socket.c:2923 __sys_recvmmsg net/socket.c:2997 [inline] __do_sys_recvmmsg net/socket.c:3020 [inline] __se_sys_recvmmsg net/socket.c:3013 [inline] __x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3013 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f462218e9a9 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:00007f461ffd5038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007f46223b6080 RCX: 00007f462218e9a9 RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003 RBP: 00007f4622210d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f46223b6080 R15: 00007ffcb7b727b8