rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 ticks this GP) idle=e184/1/0x4000000000000000 softirq=37261/37261 fqs=0 rcu: (detected by 1, t=10502 jiffies, g=28069, q=1171 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 8142 Comm: syz-executor Not tainted 6.12.0-rc2-syzkaller-00549-g01b6b9315f15 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:variable_test_bit arch/x86/include/asm/bitops.h:227 [inline] RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:239 [inline] RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline] RIP: 0010:hlock_class kernel/locking/lockdep.c:228 [inline] RIP: 0010:__lock_acquire+0x12a1/0x2050 kernel/locking/lockdep.c:5199 Code: 15 0a 00 00 48 8b 44 24 10 8b 18 81 e3 ff 1f 00 00 48 89 d8 48 c1 e8 06 48 8d 3c c5 00 c8 2c 94 be 08 00 00 00 e8 ef 2a 8e 00 <48> 0f a3 1d a7 58 bc 12 73 1d 48 69 c3 c8 00 00 00 48 8d 98 c0 46 RSP: 0018:ffffc900000077f0 EFLAGS: 00000056 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff81706f51 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff942cc800 RBP: 8313d3c9cf092d04 R08: ffffffff942cc807 R09: 1ffffffff2859900 R10: dffffc0000000000 R11: fffffbfff2859901 R12: 0000000000000000 R13: ffff888027a7c6d8 R14: 1ffff11004f4f8e5 R15: ffff888027a7c728 FS: 0000555580cdc500(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5b28736018 CR3: 000000006b936000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 debug_objects_fill_pool+0xa0/0x9f0 lib/debugobjects.c:614 debug_object_activate+0x135/0x510 lib/debugobjects.c:704 debug_hrtimer_activate kernel/time/hrtimer.c:423 [inline] debug_activate kernel/time/hrtimer.c:478 [inline] enqueue_hrtimer+0x30/0x3c0 kernel/time/hrtimer.c:1085 __run_hrtimer kernel/time/hrtimer.c:1708 [inline] __hrtimer_run_queues+0x6cb/0xd50 kernel/time/hrtimer.c:1755 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1817 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1026 [inline] __sysvec_apic_timer_interrupt+0x110/0x3f0 arch/x86/kernel/apic/apic.c:1043 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1037 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:unwind_next_frame+0x315/0x22d0 arch/x86/kernel/unwind_orc.c:505 Code: 64 48 01 d2 48 01 f2 0f 84 42 01 00 00 48 8d 5a 04 4c 8d 72 05 48 89 d8 48 c1 e8 03 48 bd 00 00 00 00 00 fc ff df 0f b6 04 28 <84> c0 0f 85 58 18 00 00 4c 89 f0 48 c1 e8 03 0f b6 04 28 84 c0 0f RSP: 0018:ffffc9000317f3b0 EFLAGS: 00000a02 RAX: 0000000000000000 RBX: ffffffff90ae971a RCX: ffffffff9035585c RDX: ffffffff90ae9716 RSI: ffffffff90ae9716 RDI: ffffffff814166e0 RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffc9000317f570 R10: ffffc9000317f4d0 R11: ffffffff8180a0e0 R12: 0000000000000000 R13: ffffc9000317f480 R14: ffffffff90ae971b R15: ffffffff81f072e4 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 save_stack+0xfb/0x1f0 mm/page_owner.c:156 __set_page_owner+0x92/0x800 mm/page_owner.c:320 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1545 [inline] get_page_from_freelist+0x3045/0x3190 mm/page_alloc.c:3457 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4733 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265 vm_area_alloc_pages mm/vmalloc.c:3568 [inline] __vmalloc_area_node mm/vmalloc.c:3646 [inline] __vmalloc_node_range_noprof+0xa2b/0x13f0 mm/vmalloc.c:3828 vmalloc_user_noprof+0x74/0x80 mm/vmalloc.c:3982 kcov_ioctl+0x56/0x640 kernel/kcov.c:716 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 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: 0033:0x7f5b2857dbfb Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00 RSP: 002b:00007fff9a7e9550 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000040000 RCX: 00007f5b2857dbfb RDX: 0000000000040000 RSI: ffffffff80086301 RDI: 00000000000000d9 RBP: 00007f5b287360f0 R08: 00000000000000d8 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g28069 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=11741 rcu: rcu_preempt kthread starved for 10502 jiffies! g28069 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 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5322 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6682 __schedule_loop kernel/sched/core.c:6759 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6774 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2615 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 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