rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 ticks this GP) idle=df7c/1/0x4000000000000000 softirq=46573/46573 fqs=0 rcu: (detected by 1, t=10502 jiffies, g=44049, q=373 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5852 Comm: udevd Not tainted 6.14.0-rc1-syzkaller-00028-g5c8c229261f1 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:26 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:87 [inline] RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:147 [inline] RIP: 0010:lock_is_held_type+0x11c/0x190 kernel/locking/lockdep.c:5925 Code: 00 00 00 48 c7 c7 e0 b8 0a 8c e8 7f 1a 00 00 b8 ff ff ff ff 65 0f c1 05 22 cd 0c 74 83 f8 01 75 44 48 c7 04 24 00 00 00 00 9c <8f> 04 24 f7 04 24 00 02 00 00 75 4c 41 f7 c4 00 02 00 00 74 01 fb RSP: 0018:ffffc90000007c20 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffff88805fc75a00 RDX: ffff88805fc75a00 RSI: ffffffff8c0ab8e0 RDI: ffffffff8c608a00 RBP: 0000000000000001 R08: ffffffff89f70b6b R09: fffff52000000f7c R10: dffffc0000000000 R11: fffff52000000f7c R12: 0000000000000046 R13: ffff88805fc75a00 R14: 00000000ffffffff R15: ffff88805fcdb300 FS: 00007f194deb2c80(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2c25ffff CR3: 0000000061da8000 CR4: 0000000000350ef0 Call Trace: lock_is_held include/linux/lockdep.h:249 [inline] advance_sched+0xcd/0xca0 net/sched/sch_taprio.c:925 __run_hrtimer kernel/time/hrtimer.c:1801 [inline] __hrtimer_run_queues+0x59d/0xd30 kernel/time/hrtimer.c:1865 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1927 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x112/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:get_current arch/x86/include/asm/current.h:49 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216 Code: 8b 3d 44 e5 71 0c 48 89 de 5b e9 b3 4e 5b 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0c 25 80 d6 03 00 65 8b 15 50 78 44 7e 81 e2 00 01 ff 00 RSP: 0018:ffffc9000440f810 EFLAGS: 00000246 RAX: ffffffff84993bc7 RBX: 0000000000000000 RCX: ffff88805fc75a00 RDX: ffff88805fc75a00 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffffff84993a0d R09: ffffffff823b8f76 R10: 0000000000000002 R11: ffff88805fc75a00 R12: ffff888148c982b0 R13: 0000000000000000 R14: 0000000000000081 R15: 0000000000000000 security_inode_permission+0x2c7/0x320 security/security.c:2324 may_lookup fs/namei.c:1821 [inline] link_path_walk+0x204/0xea0 fs/namei.c:2427 path_openat+0x266/0x3590 fs/namei.c:3985 do_filp_open+0x27f/0x4e0 fs/namei.c:4016 do_sys_openat2+0x13e/0x1d0 fs/open.c:1427 do_sys_open fs/open.c:1442 [inline] __do_sys_openat fs/open.c:1458 [inline] __se_sys_openat fs/open.c:1453 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1453 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: 0033:0x7f194df889a4 Code: 24 20 48 8d 44 24 30 48 89 44 24 28 64 8b 04 25 18 00 00 00 85 c0 75 2c 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 60 48 8b 15 55 a4 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffcf8d74850 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000008 RCX: 00007f194df889a4 RDX: 0000000000080000 RSI: 00007ffcf8d74988 RDI: 00000000ffffff9c RBP: 00007ffcf8d74988 R08: 0000000000000008 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000080000 R13: 000055cf14ed3b42 R14: 0000000000000001 R15: 000055cf14eef160 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g44049 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=33664 rcu: rcu_preempt kthread starved for 10502 jiffies! g44049 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:25816 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0x190e/0x4c90 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6856 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2024 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2226 kthread+0x7ab/0x920 kernel/kthread.c:464 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244