rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 ticks this GP) idle=28fc/1/0x4000000000000000 softirq=71106/71106 fqs=158 rcu: (detected by 0, t=10505 jiffies, g=130677, q=1122 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 28021 Comm: syz-executor.0 Not tainted 6.7.0-rc2-syzkaller-00431-g9f1f6111fd5d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 RIP: 0010:__lock_acquire+0x55/0x3b10 kernel/locking/lockdep.c:4992 Code: 00 b3 8a b5 41 44 89 44 24 08 44 8b ac 24 48 01 00 00 48 c7 84 24 98 00 00 00 69 24 96 8c 48 c7 84 24 a0 00 00 00 70 cc 67 81 <48> 89 44 24 18 48 8d 84 24 90 00 00 00 48 c1 e8 03 48 89 44 24 30 RSP: 0018:ffffc900001f0ad0 EFLAGS: 00000082 RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000 RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffffffff8da36a40 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff8f195817 R11: 0000000000000003 R12: ffffffff8da36a40 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f533ea4d6c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000200a4000 CR3: 00000000675cf000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1ae/0x520 kernel/locking/lockdep.c:5718 debug_objects_fill_pool lib/debugobjects.c:614 [inline] debug_object_activate+0x144/0x490 lib/debugobjects.c:713 debug_hrtimer_activate kernel/time/hrtimer.c:422 [inline] debug_activate kernel/time/hrtimer.c:477 [inline] enqueue_hrtimer+0x23/0x310 kernel/time/hrtimer.c:1087 __run_hrtimer kernel/time/hrtimer.c:1705 [inline] __hrtimer_run_queues+0xa12/0xc20 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1814 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1065 [inline] __sysvec_apic_timer_interrupt+0x105/0x400 arch/x86/kernel/apic/apic.c:1082 sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1076 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:stack_trace_consume_entry+0x4e/0x160 kernel/stacktrace.c:86 Code: 04 02 84 c0 74 08 3c 03 0f 8e df 00 00 00 48 8d 7b 08 8b 6b 10 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 04 02 <84> c0 74 08 3c 03 0f 8e a5 00 00 00 31 c0 3b 6b 08 0f 83 81 00 00 RSP: 0018:ffffc90015c4f238 EFLAGS: 00000a06 RAX: 0000000000000000 RBX: ffffc90015c4f320 RCX: ffffffff8131c77b RDX: 1ffff92002b89e65 RSI: ffffffff81ed48af RDI: ffffc90015c4f328 RBP: 000000000000000b R08: 0000000000000007 R09: 0000000000000000 R10: ffffffff81ed48af R11: dffffc0000000000 R12: ffffc90015c4f260 R13: ffffffff8174f490 R14: ffffc90015c4f320 R15: ffff888043cc0000 arch_stack_walk+0xde/0x170 arch/x86/kernel/stacktrace.c:27 stack_trace_save+0x96/0xd0 kernel/stacktrace.c:122 save_stack+0x160/0x1f0 mm/page_owner.c:128 __set_page_owner+0x1f/0x60 mm/page_owner.c:192 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2d0/0x350 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1544 [inline] get_page_from_freelist+0xa25/0x36d0 mm/page_alloc.c:3312 __alloc_pages+0x22e/0x2420 mm/page_alloc.c:4568 __folio_alloc+0x11/0xa0 mm/page_alloc.c:4600 __folio_alloc_node include/linux/gfp.h:247 [inline] filemap_alloc_folio mm/filemap.c:969 [inline] filemap_alloc_folio+0x154/0x490 mm/filemap.c:959 __filemap_get_folio+0x54c/0xaa0 mm/filemap.c:1918 ext4_da_write_begin+0x3c7/0x8c0 fs/ext4/inode.c:2891 generic_perform_write+0x278/0x600 mm/filemap.c:3918 ext4_buffered_write_iter+0x11f/0x3c0 fs/ext4/file.c:299 ext4_file_write_iter+0x819/0x1950 fs/ext4/file.c:696 call_write_iter include/linux/fs.h:2020 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x64f/0xdf0 fs/read_write.c:584 ksys_write+0x12f/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x40/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7f533dc7cae9 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:00007f533ea4d0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f533dd9bf80 RCX: 00007f533dc7cae9 RDX: 000000000208e24b RSI: 0000000020000100 RDI: 0000000000000003 RBP: 00007f533dcc847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f533dd9bf80 R15: 00007ffdb9fb41c8 rcu: rcu_preempt kthread starved for 9716 jiffies! g130677 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:27904 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5376 [inline] __schedule+0xedb/0x5af0 kernel/sched/core.c:6688 __schedule_loop kernel/sched/core.c:6763 [inline] schedule+0xe9/0x270 kernel/sched/core.c:6778 schedule_timeout+0x137/0x290 kernel/time/timer.c:2167 rcu_gp_fqs_loop+0x1ec/0xb10 kernel/rcu/tree.c:1631 rcu_gp_kthread+0x24b/0x380 kernel/rcu/tree.c:1830 kthread+0x2c6/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 26869 Comm: kworker/u4:12 Not tainted 6.7.0-rc2-syzkaller-00431-g9f1f6111fd5d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline] RIP: 0010:smp_call_function_many_cond+0x4e4/0x1550 kernel/smp.c:855 Code: 0b 00 85 ed 74 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 f4 4c 89 f5 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 8e c0 0b 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 24 0e 00 00 8b 43 08 31 RSP: 0018:ffffc900035ff930 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b9941a60 RCX: ffffffff817bd1d8 RDX: ffff8880439d5940 RSI: ffffffff817bd1b2 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000006 R12: ffffed101732834d R13: 0000000000000001 R14: ffff8880b9941a68 R15: ffff8880b983d8c0 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555557454788 CR3: 000000000cd77000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1023 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2006 [inline] text_poke_bp_batch+0x22b/0x750 arch/x86/kernel/alternative.c:2216 text_poke_flush arch/x86/kernel/alternative.c:2407 [inline] text_poke_flush arch/x86/kernel/alternative.c:2404 [inline] text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2414 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x1d7/0x400 kernel/jump_label.c:829 static_key_enable_cpuslocked+0x1b7/0x270 kernel/jump_label.c:205 static_key_enable+0x1a/0x20 kernel/jump_label.c:218 toggle_allocation_gate mm/kfence/core.c:830 [inline] toggle_allocation_gate+0xf4/0x250 mm/kfence/core.c:822 process_one_work+0x886/0x15d0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x2c6/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242