rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (0 ticks this GP) idle=521c/1/0x4000000000000000 softirq=104885/104885 fqs=16 rcu: (detected by 1, t=10502 jiffies, g=97921, q=193 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 24263 Comm: syz.4.4811 Not tainted 6.13.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:check_wait_context kernel/locking/lockdep.c:4866 [inline] RIP: 0010:__lock_acquire+0x709/0x2100 kernel/locking/lockdep.c:5176 Code: 10 84 c0 0f 85 df 13 00 00 48 8b 04 24 8b 28 41 89 ec ff cd 0f 88 a5 00 00 00 89 eb 83 fd 31 73 7b 48 8d 04 9b 48 8d 5c c6 20 <48> 89 d8 48 c1 e8 03 0f b6 04 10 84 c0 75 18 8b 1b 41 0f b6 04 16 RSP: 0018:ffffc90000006b70 EFLAGS: 00000083 RAX: 0000000000000014 RBX: ffff888061c647a0 RCX: 0000000000000002 RDX: dffffc0000000000 RSI: ffff888061c646e0 RDI: ffffffff94271880 RBP: 0000000000000004 R08: ffffffff94271887 R09: 1ffffffff284e310 R10: dffffc0000000000 R11: fffffbfff284e311 R12: 0000000000000005 R13: ffff888061c63c00 R14: 1ffff1100c38c8f9 R15: ffff888061c647c8 FS: 00007f4d885f26c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c2a6362 CR3: 000000007dab4000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 000000000000000e DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __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:873 debug_hrtimer_deactivate kernel/time/hrtimer.c:433 [inline] debug_deactivate+0x1b/0x220 kernel/time/hrtimer.c:475 __run_hrtimer kernel/time/hrtimer.c:1707 [inline] __hrtimer_run_queues+0x305/0xd30 kernel/time/hrtimer.c:1803 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1865 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:unwind_next_frame+0x345/0x22d0 Code: 00 00 4c 89 f0 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 6a 18 00 00 0f b6 43 01 83 e0 07 0f 84 ca 15 00 00 83 f8 01 4c 8b 6c 24 08 <49> bc 00 00 00 00 00 fc ff df 48 8b 6c 24 50 0f 84 d7 15 00 00 e9 RSP: 0018:ffffc900000072f0 EFLAGS: 00000202 RAX: 0000000000000002 RBX: ffffffff90f98c18 RCX: ffffffff9065d634 RDX: ffffffff90f98c14 RSI: ffffffff90f98bde RDI: 0000000000000001 RBP: dffffc0000000000 R08: 000000000000000a R09: ffffc900000074b0 R10: ffffc90000007410 R11: ffffffff818b3980 R12: 0000000000000009 R13: ffffc900000073c0 R14: ffffffff90f98c19 R15: ffffffff870773f3 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4119 [inline] slab_alloc_node mm/slub.c:4168 [inline] kmem_cache_alloc_node_noprof+0x1d9/0x380 mm/slub.c:4220 kmalloc_reserve+0xa8/0x2a0 net/core/skbuff.c:587 __alloc_skb+0x1f3/0x440 net/core/skbuff.c:678 __netdev_alloc_skb+0x103/0xa00 net/core/skbuff.c:742 netdev_alloc_skb include/linux/skbuff.h:3402 [inline] dev_alloc_skb include/linux/skbuff.h:3415 [inline] __ieee80211_beacon_get+0x998/0x15c0 net/mac80211/tx.c:5474 ieee80211_beacon_get_tim+0xb4/0x320 net/mac80211/tx.c:5596 ieee80211_beacon_get include/net/mac80211.h:5635 [inline] mac80211_hwsim_beacon_tx+0x39d/0x850 drivers/net/wireless/virtual/mac80211_hwsim.c:2311 __iterate_interfaces+0x297/0x570 net/mac80211/util.c:758 ieee80211_iterate_active_interfaces_atomic+0xd8/0x170 net/mac80211/util.c:794 mac80211_hwsim_beacon+0xd4/0x1f0 drivers/net/wireless/virtual/mac80211_hwsim.c:2345 __run_hrtimer kernel/time/hrtimer.c:1739 [inline] __hrtimer_run_queues+0x59b/0xd30 kernel/time/hrtimer.c:1803 hrtimer_run_softirq+0x19a/0x2c0 kernel/time/hrtimer.c:1820 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561 __do_softirq kernel/softirq.c:595 [inline] invoke_softirq kernel/softirq.c:435 [inline] __irq_exit_rcu+0xf7/0x220 kernel/softirq.c:662 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_release+0x658/0xa30 kernel/locking/lockdep.c:5874 Code: 3c 3b 00 74 08 4c 89 f7 e8 75 74 88 00 f6 84 24 91 00 00 00 02 75 77 41 f7 c5 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 27 00 00 00 00 4b c7 44 27 08 00 00 00 00 65 48 8b 04 25 RSP: 0018:ffffc9000439e520 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000873cb6 RCX: ffffc9000439e503 RDX: 0000000000000002 RSI: ffffffff8c0aaa40 RDI: ffffffff8c5edca0 RBP: ffffc9000439e660 R08: ffffffff901853f7 R09: 1ffffffff2030a7e R10: dffffc0000000000 R11: fffffbfff2030a7f R12: 1ffff92000873cb0 R13: 0000000000000246 R14: ffffc9000439e5b0 R15: dffffc0000000000 rcu_lock_release include/linux/rcupdate.h:347 [inline] rcu_read_unlock include/linux/rcupdate.h:880 [inline] page_ext_put+0xa3/0xc0 mm/page_ext.c:550 __set_page_owner+0x3f0/0x800 mm/page_owner.c:328 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1558 prep_new_page mm/page_alloc.c:1566 [inline] get_page_from_freelist+0x3651/0x37a0 mm/page_alloc.c:3476 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4753 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2269 folio_alloc_mpol_noprof+0x36/0x50 mm/mempolicy.c:2287 shmem_alloc_folio mm/shmem.c:1798 [inline] shmem_alloc_and_add_folio+0x4a0/0x1080 mm/shmem.c:1837 shmem_get_folio_gfp+0x621/0x1840 mm/shmem.c:2357 shmem_get_folio mm/shmem.c:2463 [inline] shmem_write_begin+0x165/0x350 mm/shmem.c:3119 generic_perform_write+0x346/0x990 mm/filemap.c:4055 shmem_file_write_iter+0xf9/0x120 mm/shmem.c:3295 __kernel_write_iter+0x42a/0x940 fs/read_write.c:612 dump_emit_page fs/coredump.c:884 [inline] dump_user_range+0x4f1/0x970 fs/coredump.c:945 elf_core_dump+0x3e9f/0x4790 fs/binfmt_elf.c:2129 do_coredump+0x229b/0x3100 fs/coredump.c:758 get_signal+0x140b/0x1750 kernel/signal.c:3002 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] irqentry_exit_to_user_mode+0x7e/0x250 kernel/entry/common.c:231 exc_page_fault+0x590/0x8b0 arch/x86/mm/fault.c:1542 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f4d87785d31 Code: 00 00 00 00 00 0f 1f 40 00 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 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f RSP: 002b:0000000000000040 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f4d87975fa0 RCX: 00007f4d87785d29 RDX: 0000000000000000 RSI: 0000000000000040 RDI: 0000000000000000 RBP: 00007f4d87801b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f4d87975fa0 R15: 00007ffc4ffb1e28 rcu: rcu_preempt kthread starved for 10420 jiffies! g97921 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:25232 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 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: 5985 Comm: kworker/u8:9 Not tainted 6.13.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x19f3/0x2c60 kernel/smp.c:884 Code: 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 56 e9 0b 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 01 e5 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 e4 RSP: 0018:ffffc900044276e0 EFLAGS: 00000293 RAX: ffffffff81938eab RBX: 1ffff110170c8c65 RCX: ffff888012398000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900044278e0 R08: ffffffff81938e7a R09: 1ffffffff284e310 R10: dffffc0000000000 R11: fffffbfff284e311 R12: dffffc0000000000 R13: ffff8880b8646328 R14: ffff8880b873f940 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc45dd48178 CR3: 000000000e736000 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:2114 [inline] text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2324 text_poke_flush arch/x86/kernel/alternative.c:2515 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2522 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+0xa66/0x1840 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