rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (0 ticks this GP) idle=3434/1/0x4000000000000000 softirq=14987/14987 fqs=2 rcu: (detected by 1, t=10502 jiffies, g=21797, q=217 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 7793 Comm: syz-executor.4 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:200 Code: 89 fb e8 23 00 00 00 48 8b 3d 6c 1c 1c 0c 48 89 de 5b e9 23 fb 57 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 80 d0 03 00 65 8b 15 20 db RSP: 0018:ffffc90000007d58 EFLAGS: 00000002 RAX: 0000000000010001 RBX: 0000000000000001 RCX: ffff888020598000 RDX: ffff888020598000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90000007ea8 R08: ffffffff8182801e R09: 0000000000000000 R10: ffff88807a068340 R11: ffffed100f40d06b R12: 1ffff11017285943 R13: dffffc0000000000 R14: ffff88807a068340 R15: ffff8880b942c9c0 FS: 00007efe2c3506c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020008a20 CR3: 0000000029be8000 CR4: 0000000000350ef0 Call Trace: __run_hrtimer kernel/time/hrtimer.c:1658 [inline] __hrtimer_run_queues+0x2fb/0xd00 kernel/time/hrtimer.c:1756 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1818 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline] __sysvec_apic_timer_interrupt+0x109/0x3a0 arch/x86/kernel/apic/apic.c:1049 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:srso_safe_ret+0x0/0x20 arch/x86/lib/retpoline.S:208 Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 48 b8 <48> 8d 64 24 08 c3 cc cc 0f ae e8 e8 f0 ff ff ff 0f 0b 66 2e 0f 1f RSP: 0018:ffffc9001519f470 EFLAGS: 00000246 RAX: ffffffff8180dfd8 RBX: 0000000000000001 RCX: 0000000000040000 RDX: ffffc9000a33c000 RSI: 0000000000000c78 RDI: 0000000000000c79 RBP: ffffc9001519f510 R08: ffffffff81408e18 R09: ffffffff8140a8df R10: 0000000000000003 R11: ffff888020598000 R12: ffff888020598000 R13: ffffffff8180e0a0 R14: ffffc9001519f560 R15: ffffc9001519f480 srso_return_thunk+0x5/0x5f arch/x86/lib/retpoline.S:222 arch_stack_walk+0x125/0x1b0 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 save_stack+0xfb/0x1f0 mm/page_owner.c:129 __reset_page_owner+0x44/0x2d0 mm/page_owner.c:150 reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1140 [inline] free_unref_page_prepare+0x968/0xa90 mm/page_alloc.c:2346 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2486 discard_slab mm/slub.c:2437 [inline] __put_partials+0xeb/0x130 mm/slub.c:2906 put_cpu_partial+0x17c/0x250 mm/slub.c:2981 __slab_free+0x2ea/0x3d0 mm/slub.c:4151 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x5e/0xc0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:322 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3798 [inline] slab_alloc_node mm/slub.c:3845 [inline] kmalloc_trace+0x16f/0x360 mm/slub.c:3992 kmalloc include/linux/slab.h:628 [inline] kzalloc include/linux/slab.h:749 [inline] refill_pi_state_cache kernel/futex/pi.c:20 [inline] futex_lock_pi+0x907/0xac0 kernel/futex/pi.c:930 do_futex+0x3c6/0x560 kernel/futex/syscalls.c:122 __do_sys_futex kernel/futex/syscalls.c:179 [inline] __se_sys_futex+0x3f9/0x480 kernel/futex/syscalls.c:160 do_syscall_64+0xfd/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x7efe2b67dda9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007efe2c3500c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007efe2b7abf80 RCX: 00007efe2b67dda9 RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000020008bc0 RBP: 00007efe2b6ca47a R08: 0000000020008c40 R09: 0000000000000001 R10: 0000000020008c00 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007efe2b7abf80 R15: 00007ffeb4c9f0c8 rcu: rcu_preempt kthread starved for 10490 jiffies! g21797 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:26544 pid:16 tgid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0x17d3/0x4a20 kernel/sched/core.c:6736 __schedule_loop kernel/sched/core.c:6813 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6828 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2572 rcu_gp_fqs_loop+0x2df/0x1370 kernel/rcu/tree.c:1663 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:1862 kthread+0x2f2/0x390 kernel/kthread.c:388 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 PID: 2425 Comm: kworker/u8:8 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline] RIP: 0010:smp_call_function_many_cond+0x1855/0x2960 kernel/smp.c:855 Code: 89 e6 83 e6 01 31 ff e8 d9 d5 0b 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 84 d1 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 68 d1 0b 00 eb e4 44 RSP: 0018:ffffc900099076e0 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 1ffff11017288c0d RCX: ffff888029b00000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900099078e0 R08: ffffffff818923b7 R09: 1ffffffff259caa0 R10: dffffc0000000000 R11: fffffbfff259caa1 R12: dffffc0000000000 R13: ffff8880b9446068 R14: ffff8880b953f480 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b31522000 CR3: 000000000df32000 CR4: 0000000000350ef0 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1023 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2086 [inline] text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2296 text_poke_flush arch/x86/kernel/alternative.c:2487 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2494 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x136/0x260 kernel/jump_label.c:205 static_key_enable+0x1a/0x20 kernel/jump_label.c:218 toggle_allocation_gate+0xb5/0x250 mm/kfence/core.c:826 process_one_work kernel/workqueue.c:3254 [inline] process_scheduled_works+0xa02/0x1770 kernel/workqueue.c:3335 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416 kthread+0x2f2/0x390 kernel/kthread.c:388 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243