rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P9954/1:b..l P9945/1:b..l rcu: (detected by 1, t=10502 jiffies, g=61297, q=641 ncpus=2) task:syz.2.892 state:R running task stack:22736 pid:9945 tgid:9943 ppid:9577 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 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 ea e0 87 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:ffffc90008ede7e0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920011dbd08 RCX: 38aaf7bdfd69e000 RDX: dffffc0000000000 RSI: ffffffff8beae6e0 RDI: ffffffff8c3fba80 RBP: ffffc90008ede940 R08: ffffffff93fa6847 R09: 1ffffffff27f4d08 R10: dffffc0000000000 R11: fffffbfff27f4d09 R12: 1ffff920011dbd04 R13: dffffc0000000000 R14: ffffc90008ede840 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:326 [inline] rcu_read_lock include/linux/rcupdate.h:838 [inline] folio_evictable+0x37/0x310 mm/internal.h:369 shrink_folio_list+0x942/0x8ee0 mm/vmscan.c:1071 reclaim_folio_list mm/vmscan.c:2120 [inline] reclaim_pages+0x921/0xc70 mm/vmscan.c:2156 madvise_cold_or_pageout_pte_range+0x2964/0x32a0 mm/madvise.c:550 walk_pmd_range mm/pagewalk.c:104 [inline] walk_pud_range mm/pagewalk.c:176 [inline] walk_p4d_range mm/pagewalk.c:209 [inline] walk_pgd_range+0xba1/0x1810 mm/pagewalk.c:244 __walk_page_range+0x132/0x720 mm/pagewalk.c:346 walk_page_range+0x58f/0x7c0 mm/pagewalk.c:472 madvise_pageout_page_range mm/madvise.c:609 [inline] madvise_pageout mm/madvise.c:636 [inline] madvise_vma_behavior mm/madvise.c:1042 [inline] madvise_walk_vmas mm/madvise.c:1271 [inline] do_madvise+0x3384/0x4760 mm/madvise.c:1467 __do_sys_madvise mm/madvise.c:1484 [inline] __se_sys_madvise mm/madvise.c:1482 [inline] __x64_sys_madvise+0xa6/0xc0 mm/madvise.c:1482 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: 0033:0x7f1c6157cef9 RSP: 002b:00007f1c60fff038 EFLAGS: 00000246 ORIG_RAX: 000000000000001c RAX: ffffffffffffffda RBX: 00007f1c61735f80 RCX: 00007f1c6157cef9 RDX: 0000000000000015 RSI: 0000000000600000 RDI: 0000000020000000 RBP: 00007f1c615ef046 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f1c61735f80 R15: 00007ffc7fa5ce48 task:syz.3.885 state:R running task stack:26000 pid:9954 tgid:9923 ppid:9451 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6708 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6732 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0x130/0x140 kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] __wake_up_common_lock+0x18c/0x1e0 kernel/sched/wait.c:108 sock_def_readable+0x20f/0x5b0 net/core/sock.c:3374 tcp_data_queue+0x20fd/0x76c0 net/ipv4/tcp_input.c:5283 tcp_rcv_established+0xfba/0x2020 net/ipv4/tcp_input.c:6230 tcp_v4_do_rcv+0x96d/0xc70 net/ipv4/tcp_ipv4.c:1911 sk_backlog_rcv include/net/sock.h:1111 [inline] __release_sock+0x214/0x350 net/core/sock.c:3004 release_sock+0x61/0x1f0 net/core/sock.c:3558 sk_stream_wait_memory+0x762/0xfa0 net/core/stream.c:145 tcp_sendmsg_locked+0x1471/0x4e10 net/ipv4/tcp.c:1312 tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1354 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x1a6/0x270 net/socket.c:745 __sys_sendto+0x3a4/0x4f0 net/socket.c:2204 __do_sys_sendto net/socket.c:2216 [inline] __se_sys_sendto net/socket.c:2212 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2212 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: 0033:0x7f81ce77cef9 RSP: 002b:00007f81cf641038 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f81ce936058 RCX: 00007f81ce77cef9 RDX: 00000000fffffea5 RSI: 0000000020000480 RDI: 0000000000000003 RBP: 00007f81ce7ef046 R08: 0000000000000000 R09: 00000000fffffcef R10: 000000000000c000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f81ce936058 R15: 00007ffff6a40b78 rcu: rcu_preempt kthread starved for 10582 jiffies! g61297 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:26448 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 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+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: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline] NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:111