rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=2074/1/0x4000000000000000 softirq=19362/19364 fqs=4 rcu: (detected by 1, t=10503 jiffies, g=16533, q=789 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 7493 Comm: syz-executor Not tainted 6.12.0-rc2-syzkaller-00571-g60b4d49b9621 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:119 [inline] RIP: 0010:lock_acquire+0x120/0x550 kernel/locking/lockdep.c:5801 Code: c0 7c 43 1d 90 48 c1 e8 03 42 0f b6 04 28 84 c0 0f 85 ff 02 00 00 83 3d 69 ec ac 0e 00 0f 84 42 01 00 00 65 8b 05 60 33 92 7e <85> c0 0f 85 8f 01 00 00 65 48 8b 1c 25 00 d8 03 00 48 81 c3 dc 0a RSP: 0018:ffffc90000007a40 EFLAGS: 00000002 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff817056d4 RDX: 0000000000000000 RSI: ffffffff8c60fb00 RDI: ffffffff8c60fac0 RBP: ffffc90000007b88 R08: ffffffff901d112f R09: 1ffffffff203a225 R10: dffffc0000000000 R11: fffffbfff203a226 R12: 1ffff92000000f50 R13: dffffc0000000000 R14: 0000000000000000 R15: dffffc0000000000 FS: 00005555559fe500(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c31f9c6 CR3: 0000000062cc2000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 debug_object_deactivate+0x158/0x390 lib/debugobjects.c:763 debug_hrtimer_deactivate kernel/time/hrtimer.c:428 [inline] debug_deactivate+0x1b/0x220 kernel/time/hrtimer.c:484 __run_hrtimer kernel/time/hrtimer.c:1659 [inline] __hrtimer_run_queues+0x305/0xd50 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:lockdep_enabled kernel/locking/lockdep.c:122 [inline] RIP: 0010:lock_release+0x112/0xa30 kernel/locking/lockdep.c:5838 Code: 83 3d 7d c5 ac 0e 00 4c 8b 74 24 18 0f 84 55 05 00 00 65 8b 05 6f 0c 92 7e 85 c0 0f 85 46 05 00 00 65 48 8b 04 25 00 d8 03 00 <48> 89 44 24 20 48 8d 98 dc 0a 00 00 48 89 d8 48 c1 e8 03 42 0f b6 RSP: 0018:ffffc9000d7af8c0 EFLAGS: 00000246 RAX: ffff88802d4d8000 RBX: 0000000000000000 RCX: ffffffff81707dc0 RDX: 0000000000000000 RSI: ffffffff8c60fb00 RDI: ffffffff8c60fac0 RBP: ffffc9000d7af9f8 R08: ffffffff901d112f R09: 1ffffffff203a225 R10: dffffc0000000000 R11: fffffbfff203a226 R12: 1ffff92001af5f24 R13: ffffffff81f03cef R14: ffffffff8ea37160 R15: dffffc0000000000 __fs_reclaim_release mm/page_alloc.c:3839 [inline] fs_reclaim_release mm/page_alloc.c:3865 [inline] might_alloc include/linux/sched/mm.h:319 [inline] prepare_alloc_pages+0x1af/0x5b0 mm/page_alloc.c:4493 __alloc_pages_noprof+0x16f/0x710 mm/page_alloc.c:4722 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: 0033:0x7f7436d7dbfb 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:00007ffd34b116f0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000040000 RCX: 00007f7436d7dbfb RDX: 0000000000040000 RSI: ffffffff80086301 RDI: 00000000000000e1 RBP: 00007f7436f367b0 R08: 00000000000000da R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 10468 jiffies! g16533 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:25744 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 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 12 Comm: kworker/u8:1 Not tainted 6.12.0-rc2-syzkaller-00571-g60b4d49b9621 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:smp_call_function_many_cond+0x1a0b/0x2ca0 kernel/smp.c:884 Code: 00 00 00 00 fc ff df 75 07 e8 01 ef 0b 00 eb 38 f3 90 42 0f b6 04 23 84 c0 75 11 41 f7 45 00 01 00 00 00 74 1e e8 e5 ee 0b 00 e4 44 89 e9 80 e1 07 80 c1 03 38 c1 7c e2 4c 89 ef e8 1e 9f 75 RSP: 0018:ffffc900001176e0 EFLAGS: 00000293 RAX: ffffffff8188f86b RBX: 1ffff110170c8ca9 RCX: ffff88801ce85a00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900001178e0 R08: ffffffff8188f83a R09: 1ffffffff2859900 R10: dffffc0000000000 R11: fffffbfff2859901 R12: dffffc0000000000 R13: ffff8880b8646548 R14: ffff8880b873fcc0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb7b4de7f98 CR3: 000000000e734000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1051 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2085 [inline] text_poke_bp_batch+0x726/0xb30 arch/x86/kernel/alternative.c:2357 text_poke_flush arch/x86/kernel/alternative.c:2486 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2493 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x136/0x260 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xbc/0x260 mm/kfence/core.c:849 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 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