rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5484/1:b..l P5977/1:b..l P5803/2:b..l rcu: (detected by 0, t=10502 jiffies, g=11545, q=338 ncpus=2) task:syz-executor state:R running task stack:23312 pid:5803 tgid:5803 ppid:5801 task_flags:0x400100 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6944 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __local_bh_enable_ip+0x107/0x120 kernel/softirq.c:396 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:919 [inline] __dev_queue_xmit+0x8b0/0x43e0 net/core/dev.c:4676 dev_queue_xmit include/linux/netdevice.h:3313 [inline] neigh_hh_output include/net/neighbour.h:523 [inline] neigh_output include/net/neighbour.h:537 [inline] ip_finish_output2+0xc34/0x2180 net/ipv4/ip_output.c:236 __ip_finish_output net/ipv4/ip_output.c:314 [inline] __ip_finish_output+0x49e/0x950 net/ipv4/ip_output.c:296 ip_finish_output+0x35/0x380 net/ipv4/ip_output.c:324 NF_HOOK_COND include/linux/netfilter.h:303 [inline] ip_output+0x13b/0x2a0 net/ipv4/ip_output.c:434 dst_output include/net/dst.h:459 [inline] ip_local_out net/ipv4/ip_output.c:130 [inline] __ip_queue_xmit+0x1a8d/0x22d0 net/ipv4/ip_output.c:528 __tcp_transmit_skb+0x2b39/0x3ec0 net/ipv4/tcp_output.c:1471 tcp_transmit_skb net/ipv4/tcp_output.c:1489 [inline] tcp_write_xmit+0x12b1/0x8560 net/ipv4/tcp_output.c:2832 __tcp_push_pending_frames+0xaf/0x390 net/ipv4/tcp_output.c:3015 tcp_push_pending_frames include/net/tcp.h:2124 [inline] tcp_data_snd_check net/ipv4/tcp_input.c:5753 [inline] tcp_rcv_established+0x868/0x2140 net/ipv4/tcp_input.c:6290 tcp_v4_do_rcv+0x5ca/0xa90 net/ipv4/tcp_ipv4.c:1918 sk_backlog_rcv include/net/sock.h:1122 [inline] __release_sock+0x31b/0x400 net/core/sock.c:3123 release_sock+0x5a/0x220 net/core/sock.c:3677 tcp_sendmsg+0x38/0x50 net/ipv4/tcp.c:1359 inet_sendmsg+0xb9/0x140 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:733 [inline] sock_write_iter+0x4ac/0x5b0 net/socket.c:1137 new_sync_write fs/read_write.c:586 [inline] vfs_write+0x5ae/0x1150 fs/read_write.c:679 ksys_write+0x207/0x250 fs/read_write.c:731 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: 0033:0x7f409d78bbe0 RSP: 002b:00007ffdfb51b8b8 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000045f7e9380 RCX: 00007f409d78bbe0 RDX: 000000000004f410 RSI: 00007f40961b0bf0 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000007 R09: 00000000005ffde8 R10: 1401ad6e6ebaaaae R11: 0000000000000202 R12: 000000000004f410 R13: 000055555ca65f20 R14: 00007ffdfb51bd80 R15: 00007f40961b0bf0 task:kworker/u8:9 state:R running task stack:24384 pid:5977 tgid:5977 ppid:2 task_flags:0x24248060 flags:0x00004000 Workqueue: writeback wb_workfn (flush-8:0) Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7087 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:PagePoisoned include/linux/page-flags.h:294 [inline] RIP: 0010:page_to_nid include/linux/mm.h:1648 [inline] RIP: 0010:page_zone include/linux/mm.h:1869 [inline] RIP: 0010:folio_zone include/linux/mm.h:1879 [inline] RIP: 0010:zone_stat_mod_folio include/linux/vmstat.h:443 [inline] RIP: 0010:folio_clear_dirty_for_io+0x3e6/0x800 mm/page-writeback.c:3032 Code: df e8 6e ed 31 00 9c 58 25 00 02 00 00 31 ff 48 89 c6 48 89 44 24 08 e8 b8 f1 c6 ff 48 8b 44 24 08 48 85 c0 0f 85 c6 03 00 00 75 f6 c6 ff 48 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 RSP: 0018:ffffc9000215ee28 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffffea0001745d00 RCX: ffffffff81f2edc0 RDX: ffff888029890000 RSI: ffffffff81f2edd3 RDI: 0000000000000007 RBP: ffffea0001745d01 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000006 R12: 0000000000000000 R13: ffff88807aceaa50 R14: ffff8880294fc068 R15: 0000000000000000 mpage_submit_folio+0x80/0x350 fs/ext4/inode.c:1913 mpage_map_and_submit_buffers+0x590/0xae0 fs/ext4/inode.c:2178 mpage_map_and_submit_extent fs/ext4/inode.c:2310 [inline] ext4_do_writepages+0x1b07/0x32d0 fs/ext4/inode.c:2735 ext4_writepages+0x303/0x730 fs/ext4/inode.c:2824 do_writepages+0x1b3/0x820 mm/page-writeback.c:2687 __writeback_single_inode+0x166/0xfa0 fs/fs-writeback.c:1680 writeback_sb_inodes+0x606/0xfa0 fs/fs-writeback.c:1976 __writeback_inodes_wb+0xff/0x2e0 fs/fs-writeback.c:2047 wb_writeback+0x803/0xb80 fs/fs-writeback.c:2158 wb_check_old_data_flush fs/fs-writeback.c:2262 [inline] wb_do_writeback fs/fs-writeback.c:2315 [inline] wb_workfn+0x8c0/0xbc0 fs/fs-writeback.c:2343 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3400 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 task:dhcpcd state:R running task stack:25552 pid:5484 tgid:5484 ppid:1 task_flags:0x400140 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6944 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 unwind_next_frame+0x1776/0x20c0 arch/x86/kernel/unwind_orc.c:672 arch_stack_walk+0x95/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 save_stack+0x162/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x8d/0x400 mm/page_owner.c:297 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_frozen_pages+0x6db/0xfb0 mm/page_alloc.c:2660 __put_partials+0x14c/0x170 mm/slub.c:3153 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4e/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4115 [inline] slab_alloc_node mm/slub.c:4164 [inline] kmem_cache_alloc_node_noprof+0x223/0x3c0 mm/slub.c:4216 __alloc_skb+0x2b1/0x380 net/core/skbuff.c:596 alloc_skb include/linux/skbuff.h:1331 [inline] alloc_skb_with_frags+0xe4/0x850 net/core/skbuff.c:6522 sock_alloc_send_pskb+0x7f1/0x980 net/core/sock.c:2914 unix_dgram_sendmsg+0x45e/0x1880 net/unix/af_unix.c:2017 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:733 [inline] sock_write_iter+0x4fe/0x5b0 net/socket.c:1137 do_iter_readv_writev+0x655/0x950 fs/read_write.c:820 vfs_writev+0x363/0xdd0 fs/read_write.c:1050 do_writev+0x297/0x340 fs/read_write.c:1096 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: 0033:0x7f743c84ae03 RSP: 002b:00007fffbef45f78 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 00007fffbef462d8 RCX: 00007f743c84ae03 RDX: 0000000000000005 RSI: 00007fffbef45f90 RDI: 000000000000000a RBP: 000000000000012c R08: 000000000000000a R09: 00007fffbef45fd0 R10: 00007fffbef45fd8 R11: 0000000000000246 R12: 000055bdfded8db0 R13: 000055bdc1ecff88 R14: 00000000ffffffff R15: 0000000000000001 rcu: rcu_preempt kthread starved for 6542 jiffies! g11545 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:26304 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6857 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2024 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2226 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 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:106 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:111