rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5189/1:b..l P5942/1:b..l rcu: (detected by 0, t=10502 jiffies, g=10377, q=1247 ncpus=2) task:syz-executor state:R running task stack:23880 pid:5942 tgid:5942 ppid:5940 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__update_page_owner_handle+0x167/0x550 mm/page_owner.c:258 Code: 8b ff 4c 39 f3 0f 84 1d 02 00 00 e8 83 9a 8b ff 48 8b 1d cc 32 29 0c 4c 01 e3 48 8d 7b 08 48 89 f8 48 c1 e8 03 42 0f b6 04 28 <84> c0 74 08 3c 03 0f 8e 74 03 00 00 8b 44 24 14 89 43 08 48 89 d8 RSP: 0000:ffffc900036e74d8 EFLAGS: 00000a06 RAX: 0000000000000000 RBX: ffff88801e1f6858 RCX: ffffffff82334e5f RDX: ffff88802845a4c0 RSI: ffffffff82334e6d RDI: ffff88801e1f6860 RBP: 000000000005e481 R08: 0000000000000006 R09: 0000000000000001 R10: 0000000000000000 R11: ffff88802845aff0 R12: ffff88801e1f6850 R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000 __set_page_owner+0x126/0x560 mm/page_owner.c:342 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1857 prep_new_page mm/page_alloc.c:1865 [inline] get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3915 __alloc_frozen_pages_noprof+0x25f/0x2430 mm/page_alloc.c:5210 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2486 folio_alloc_mpol_noprof+0x36/0x2f0 mm/mempolicy.c:2505 vma_alloc_folio_noprof+0xed/0x1e0 mm/mempolicy.c:2540 folio_prealloc mm/memory.c:1193 [inline] wp_page_copy mm/memory.c:3719 [inline] do_wp_page+0x202f/0x5010 mm/memory.c:4180 handle_pte_fault mm/memory.c:6289 [inline] __handle_mm_fault+0x1bd2/0x2bb0 mm/memory.c:6411 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6580 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+0x64/0xc0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7f93de385d16 RSP: 002b:00007ffc96882ff0 EFLAGS: 00010202 RAX: 0000000000000045 RBX: 0000000000000000 RCX: 00007f93de385e93 RDX: 0000000000000045 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: 00005555654c67d0 R11: 0000000000000246 R12: 0000000000000045 R13: ffffffffffffffa8 R14: 0000000000000006 R15: 00007ffc96883180 task:udevd state:R running task stack:26504 pid:5189 tgid:5189 ppid:1 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_is_held_type+0x107/0x150 kernel/locking/lockdep.c:5945 Code: 00 00 b8 ff ff ff ff 65 0f c1 05 5c c0 3a 08 83 f8 01 75 2d 9c 58 f6 c4 02 75 43 48 f7 04 24 00 02 00 00 74 01 fb 48 83 c4 08 <44> 89 e8 5b 5d 41 5c 41 5d 41 5e 41 5f e9 87 2c 03 00 45 31 ed eb RSP: 0018:ffffc90003cf77d8 EFLAGS: 00000286 RAX: 0000000000000046 RBX: ffff88807ae18bd0 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff8daa8998 RDI: ffffffff8bf2b400 RBP: ffffffff8e3c96a0 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: ffff88807ae18b30 R12: ffff88807ae18000 R13: 0000000000000001 R14: 00000000ffffffff R15: 0000000000000004 sk_filter_trim_cap+0x6b2/0xde0 net/core/filter.c:163 sk_filter include/linux/filter.h:1102 [inline] do_one_broadcast net/netlink/af_netlink.c:1480 [inline] netlink_broadcast_filtered+0x65d/0xf90 net/netlink/af_netlink.c:1533 netlink_broadcast+0x39/0x50 net/netlink/af_netlink.c:1557 uevent_net_broadcast_untagged lib/kobject_uevent.c:331 [inline] kobject_uevent_net_broadcast lib/kobject_uevent.c:410 [inline] kobject_uevent_env+0xcbc/0x1920 lib/kobject_uevent.c:608 kobject_synth_uevent+0x7d4/0x8a0 lib/kobject_uevent.c:207 uevent_store+0x24/0x80 drivers/base/core.c:2773 dev_attr_store+0x58/0x80 drivers/base/core.c:2437 sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:142 kernfs_fop_write_iter+0x3af/0x570 fs/kernfs/file.c:352 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x7d3/0x11d0 fs/read_write.c:686 ksys_write+0x12a/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f821b0a7407 RSP: 002b:00007ffedb8e21e0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f821b893880 RCX: 00007f821b0a7407 RDX: 0000000000000007 RSI: 0000561426e09dd0 RDI: 000000000000000c RBP: 0000561426e09dd0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000007 R13: 0000561426e031e0 R14: 00007f821b1efea0 R15: 00007ffedb8e2580 rcu: rcu_preempt kthread starved for 10528 jiffies! g10377 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:28584 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6960 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 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: 6451 Comm: iou-sqp-6448 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline] RIP: 0010:write_comp_data+0x11/0x90 kernel/kcov.c:246 Code: 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 49 89 d2 49 89 f8 49 89 f1 65 48 8b 15 37 ce f3 11 <65> 8b 05 48 ce f3 11 a9 00 01 ff 00 74 1d f6 c4 01 74 67 a9 00 00 RSP: 0018:ffffc90004e67c98 EFLAGS: 00000246 RAX: ffffed100f53e000 RBX: 0000000000000000 RCX: ffffffff84a4ce7d RDX: ffff88807a9f0000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: ffff88806ceb0bc0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: ffff88807a9f0b30 R12: 0000000000000000 R13: ffff88806ceb1000 R14: ffff88807a9f0000 R15: dffffc0000000000 FS: 00007f4cefb6c6c0(0000) GS:ffff8881249f5000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f93de5e6018 CR3: 0000000076d8b000 CR4: 00000000003526f0 Call Trace: signal_pending include/linux/sched/signal.h:393 [inline] io_sq_thread+0xcbd/0x1e30 io_uring/sqpoll.c:337 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246