rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7237/1:b..l (detected by 0, t=10503 jiffies, g=42985, q=159 ncpus=2) task:udevd state:R running task stack:24576 pid:7237 ppid:3623 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873 irqentry_exit+0x63/0x70 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:seqcount_lockdep_reader_access+0x17a/0x1c0 include/linux/seqlock.h:105 Code: ff 4d 85 ed 75 16 e8 05 ba 92 ff eb 15 e8 fe b9 92 ff e8 a9 74 21 08 4d 85 ed 74 ea e8 ef b9 92 ff fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 27 00 00 00 00 66 43 c7 44 27 09 00 00 43 c6 44 27 0b 00 RSP: 0018:ffffc900037c7740 EFLAGS: 00000293 RAX: ffffffff81ee1c81 RBX: 0000000000000000 RCX: ffff88802771d940 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900037c7800 R08: dffffc0000000000 R09: fffffbfff1bfd0b6 R10: fffffbfff1bfd0b6 R11: 1ffffffff1bfd0b5 R12: dffffc0000000000 R13: 0000000000000200 R14: ffffffff81edf53d R15: 1ffff920006f8ee8 read_seqbegin include/linux/seqlock.h:893 [inline] read_seqbegin_or_lock include/linux/seqlock.h:1187 [inline] prepend_path+0xed/0xc20 fs/d_path.c:165 d_absolute_path+0x9e/0x140 fs/d_path.c:233 tomoyo_get_absolute_path security/tomoyo/realpath.c:101 [inline] tomoyo_realpath_from_path+0x2d5/0x5d0 security/tomoyo/realpath.c:271 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x1fd/0x550 security/tomoyo/file.c:822 security_inode_getattr+0xcf/0x120 security/security.c:1361 vfs_getattr+0x26/0x3a0 fs/stat.c:158 vfs_statx+0x16e/0x650 fs/stat.c:233 vfs_fstatat fs/stat.c:267 [inline] __do_sys_newfstatat fs/stat.c:437 [inline] __se_sys_newfstatat fs/stat.c:431 [inline] __x64_sys_newfstatat+0x155/0x1e0 fs/stat.c:431 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fd10e511b0a RSP: 002b:00007ffc3ab19848 EFLAGS: 00000246 ORIG_RAX: 0000000000000106 RAX: ffffffffffffffda RBX: 0000000000000014 RCX: 00007fd10e511b0a RDX: 00007ffc3ab19850 RSI: 00007ffc3ab19920 RDI: 00000000ffffff9c RBP: 00007ffc3ab1a960 R08: 000055e1790e91a0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000055e1790e3db0 R13: 0000000000000000 R14: 000055e162a296d7 R15: 00007ffc3ab1bab0 rcu: rcu_preempt kthread starved for 10532 jiffies! g42985 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:27840 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706 rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8573 Comm: syz.6.1009 Not tainted 6.1.141-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:122 [inline] RIP: 0010:lock_acquire+0x147/0x490 kernel/locking/lockdep.c:5638 Code: c0 0f 85 2f 01 00 00 65 4c 8b 35 44 84 9f 7e 49 81 c6 dc 0a 00 00 4c 89 f0 48 c1 e8 03 42 0f b6 04 38 84 c0 0f 85 19 02 00 00 <41> 83 3e 00 0f 85 02 01 00 00 48 c7 84 24 a0 00 00 00 00 00 00 00 RSP: 0018:ffffc900001e0800 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 08ff7e7a5ca49a00 RDX: 0000000000000000 RSI: ffffffff8abf1340 RDI: ffffffff8abf1300 RBP: ffffc900001e0908 R08: dffffc0000000000 R09: fffffbfff1bfd0b6 R10: fffffbfff1bfd0b6 R11: 1ffffffff1bfd0b5 R12: 0000000000000001 R13: 1ffff9200003c10c R14: ffff88802771c65c R15: dffffc0000000000 FS: 00007f33e6c806c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c2873ca CR3: 000000005ff70000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] rcu_read_lock include/linux/rcupdate.h:791 [inline] page_ext_get+0x3a/0x2a0 mm/page_ext.c:157 __set_page_owner+0x24/0x60 mm/page_owner.c:192 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2532 prep_new_page mm/page_alloc.c:2539 [inline] get_page_from_freelist+0x1a26/0x1ac0 mm/page_alloc.c:4328 __alloc_pages+0x1df/0x4e0 mm/page_alloc.c:5614 alloc_slab_page+0x5d/0x160 mm/slub.c:1794 allocate_slab mm/slub.c:1939 [inline] new_slab+0x87/0x2c0 mm/slub.c:1992 ___slab_alloc+0xbc6/0x1220 mm/slub.c:3180 __slab_alloc mm/slub.c:3279 [inline] slab_alloc_node mm/slub.c:3364 [inline] slab_alloc mm/slub.c:3406 [inline] __kmem_cache_alloc_lru mm/slub.c:3413 [inline] kmem_cache_alloc+0x1b7/0x2f0 mm/slub.c:3422 __sigqueue_alloc+0x40c/0x520 kernel/signal.c:436 __send_signal_locked+0x22f/0xde0 kernel/signal.c:1129 do_send_sig_info kernel/signal.c:1301 [inline] group_send_sig_info+0x1f6/0x250 kernel/signal.c:1449 do_bpf_send_signal+0x7b/0x150 kernel/trace/bpf_trace.c:840 irq_work_single+0xd1/0x230 kernel/irq_work.c:211 irq_work_run_list kernel/irq_work.c:242 [inline] irq_work_run+0x152/0x2e0 kernel/irq_work.c:251 __sysvec_irq_work+0xba/0x350 arch/x86/kernel/irq_work.c:22 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0x98/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728 RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline] RIP: 0010:static_key_false include/linux/jump_label.h:207 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:147 [inline] RIP: 0010:wrmsr arch/x86/include/asm/msr.h:254 [inline] RIP: 0010:native_apic_msr_write+0x35/0x50 arch/x86/include/asm/apic.h:206 Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 89 f6 31 d2 e9 4f 99 f8 02 66 2e 0f 1f 84 00 00 00 00 00 RSP: 0018:ffffc90004c27cb0 EFLAGS: 00000246 RAX: 00000000000000f6 RBX: ffffffff8c3d0b78 RCX: 000000000000083f RDX: 0000000000000000 RSI: 00000000000000f6 RDI: 000000000000083f RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff52000984f85 R10: fffff52000984f85 R11: 1ffff92000984f84 R12: ffff8880b8f33e01 R13: dffffc0000000000 R14: dffffc0000000000 R15: 0000000000000020 arch_irq_work_raise+0x82/0xd0 arch/x86/kernel/irq_work.c:31 irq_work_queue+0x95/0x140 kernel/irq_work.c:114 bpf_send_signal_common+0x2b2/0x420 kernel/trace/bpf_trace.c:879 ____bpf_send_signal kernel/trace/bpf_trace.c:888 [inline] bpf_send_signal+0x15/0x20 kernel/trace/bpf_trace.c:886 bpf_prog_7ba5217f62dcd359+0x38/0x3c bpf_dispatcher_nop_func include/linux/bpf.h:1001 [inline] __bpf_prog_run include/linux/filter.h:603 [inline] bpf_prog_run include/linux/filter.h:610 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2285 [inline] bpf_trace_run2+0x1cd/0x3b0 kernel/trace/bpf_trace.c:2324 __bpf_trace_sys_enter+0x60/0x70 include/trace/events/syscalls.h:18 trace_sys_enter+0x6b/0x80 include/trace/events/syscalls.h:18 syscall_trace_enter+0xf0/0x150 kernel/entry/common.c:81 do_syscall_64+0x24/0xa0 arch/x86/entry/common.c:77 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f33e5d2ab19 Code: 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 04 25 RSP: 002b:00007f33e6c7fb40 EFLAGS: 00000246 ORIG_RAX: 000000000000000f RAX: ffffffffffffffda RBX: 00007f33e5fb5fa8 RCX: 00007f33e5d2ab19 RDX: 00007f33e6c7fb40 RSI: 00007f33e6c7fc70 RDI: 0000000000000011 RBP: 00007f33e5fb5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f33e5fb5fac R13: 0000000000000000 R14: 00007fffeafab360 R15: 00007fffeafab448