rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=bd04/1/0x4000000000000000 softirq=31342/31351 fqs=2 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7193/1:b..l rcu: (detected by 1, t=10502 jiffies, g=24205, q=218 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5841 Comm: syz-executor Not tainted 6.15.0-rc1-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:task_irq_context kernel/locking/lockdep.c:4683 [inline] RIP: 0010:__lock_acquire+0x27d/0xd80 kernel/locking/lockdep.c:5172 Code: ff ff 41 23 54 cd 20 09 c2 41 89 54 cd 20 48 8b 94 24 80 00 00 00 49 89 54 cd 08 4d 89 7c cd 10 48 8b 54 24 78 49 89 54 cd 18 <65> 8b 15 78 c5 c6 11 31 f6 85 d2 40 0f 95 c6 31 d2 83 bd d4 0a 00 RSP: 0018:ffffc90000007b80 EFLAGS: 00000002 RAX: 000000000000006d RBX: 0000000000000000 RCX: 0000000000000005 RDX: 0000000000000000 RSI: 000000000000006d RDI: 0000000000000001 RBP: ffff88807e389e00 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffff88807e38a8f0 R14: 0000000000000000 R15: ffff8880b86276d8 FS: 000055559251e500(0000) GS:ffff888124fc9000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff68cda7bac CR3: 0000000060d4c000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x116/0x2f0 kernel/locking/lockdep.c:5866 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0xd3/0x120 kernel/locking/spinlock.c:170 __run_hrtimer kernel/time/hrtimer.c:1765 [inline] __hrtimer_run_queues+0x67b/0xd40 kernel/time/hrtimer.c:1825 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1887 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+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__asan_memset+0x16/0x50 mm/kasan/shadow.c:84 Code: 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 56 53 48 89 d3 41 89 f6 48 89 fd 48 8b 4c 24 18 <48> 89 d6 ba 01 00 00 00 e8 5d e6 ff ff 84 c0 74 12 48 89 ef 44 89 RSP: 0018:ffffc90003f07828 EFLAGS: 00000246 RAX: ffffc90003f07980 RBX: 0000000000000010 RCX: ffffffff816df656 RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc90003f079d0 RBP: ffffc90003f079d0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffc90003f07980 R13: ffffc90003f08000 R14: 0000000000000000 R15: ffffc90003f00000 unwind_next_frame+0xb46/0x23b0 arch/x86/kernel/unwind_orc.c:592 __unwind_start+0x59a/0x740 arch/x86/kernel/unwind_orc.c:758 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xe7/0x150 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0x11a/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x9d/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x236/0x370 mm/slub.c:4362 kmalloc_noprof include/linux/slab.h:905 [inline] slab_free_hook mm/slub.c:2341 [inline] slab_free mm/slub.c:4646 [inline] kmem_cache_free+0x16e/0x410 mm/slub.c:4748 fput_close_sync+0x1ef/0x270 fs/file_table.c:570 __do_sys_close fs/open.c:1581 [inline] __se_sys_close fs/open.c:1566 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1566 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f820118bdca Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 43 91 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 a3 91 02 00 8b 44 24 RSP: 002b:00007ffcadc0cea0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 0000000000001cd7 RCX: 00007f820118bdca RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 00007ffcadc0cf70 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007ffcadc0e000 R13: 00007f820120e08c R14: 000055559251e4a8 R15: 0000000000000005 task:udevd state:R running task stack:22600 pid:7193 tgid:7193 ppid:5202 task_flags:0x400140 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1b33/0x51f0 kernel/sched/core.c:6767 preempt_schedule_irq+0xfe/0x1c0 kernel/sched/core.c:7090 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:orc_ip arch/x86/kernel/unwind_orc.c:80 [inline] RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:102 [inline] RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:227 [inline] RIP: 0010:unwind_next_frame+0x784/0x23b0 arch/x86/kernel/unwind_orc.c:494 Code: 89 c1 48 c1 f9 02 48 c1 e8 3f 48 01 c8 48 83 e0 fe 49 8d 1c 46 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 <84> c0 75 27 48 63 03 48 01 d8 48 8d 4b 04 4c 39 e0 4c 0f 46 f1 48 RSP: 0018:ffffc9001019f7e8 EFLAGS: 00000a07 RAX: 0000000000000000 RBX: ffffffff907b0c14 RCX: dffffc0000000000 RDX: ffffffff90f758c6 RSI: ffffffff8ca0e1c0 RDI: ffffffff8ca0e180 RBP: ffffffff907b0c1c R08: 000000000000000a R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff823bbb2e R13: ffffffff907b0c10 R14: ffffffff907b0c10 R15: ffffffff907b0c10 arch_stack_walk+0x11e/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x11a/0x1d0 kernel/stacktrace.c:122 kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47 kasan_record_aux_stack+0xbf/0xd0 mm/kasan/generic.c:548 __call_rcu_common kernel/rcu/tree.c:3082 [inline] call_rcu+0x172/0xad0 kernel/rcu/tree.c:3202 slab_free_hook mm/slub.c:2353 [inline] slab_free mm/slub.c:4646 [inline] kmem_cache_free+0x312/0x410 mm/slub.c:4748 fput_close_sync+0x1ef/0x270 fs/file_table.c:570 __do_sys_close fs/open.c:1581 [inline] __se_sys_close fs/open.c:1566 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1566 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7598f1a37f RSP: 002b:00007ffff9153068 EFLAGS: 00000202 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 0000564c05346730 RCX: 00007f7598f1a37f RDX: 00007f7598fed860 RSI: 0000564c053efbe0 RDI: 0000000000000009 RBP: 0000000000000000 R08: 0000000000000000 R09: 00007ffff9152ba8 R10: 000000000000010f R11: 0000000000000202 R12: 0000000000000000 R13: 00007ffff91530c8 R14: 00007ffff91534c8 R15: 0000564bf51c1ec8 rcu: rcu_preempt kthread starved for 10498 jiffies! g24205 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:26976 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1b33/0x51f0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x163/0x360 kernel/sched/core.c:6860 schedule_timeout+0x15b/0x2b0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2e1/0x1340 kernel/rcu/tree.c:2046 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2248 kthread+0x7b7/0x940 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 8419 Comm: syz.2.1082 Not tainted 6.15.0-rc1-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:lock_acquire+0x167/0x2f0 arch/x86/include/asm/irqflags.h:-1 Code: c7 44 24 10 00 00 00 00 9c 8f 44 24 10 f7 44 24 10 00 02 00 00 0f 85 fd 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 65 48 8b 45 00 <48> 3b 44 24 38 0f 85 72 01 00 00 48 83 c4 40 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc90000a082c8 EFLAGS: 00000206 RAX: 6aa8a4f61fda2800 RBX: ffffffff8ed3dfe0 RCX: 6aa8a4f61fda2800 RDX: 0000000000000000 RSI: ffffffff8e4ea087 RDI: ffffffff8ca0e1e0 RBP: ffffffff93657020 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000002 R14: 0000000000000246 R15: 0000000000000000 FS: 00007ff68da0e6c0(0000) GS:ffff8881250c9000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c3a2b29 CR3: 0000000032222000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] is_bpf_text_address+0x46/0x2a0 kernel/bpf/core.c:772 kernel_text_address+0xa7/0xe0 kernel/extable.c:125 __kernel_text_address+0xd/0x40 kernel/extable.c:79 unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:369 arch_stack_walk+0xff/0x150 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x11a/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:4151 [inline] slab_alloc_node mm/slub.c:4200 [inline] kmem_cache_alloc_node_noprof+0x1f2/0x3b0 mm/slub.c:4252 __alloc_skb+0x1c2/0x480 net/core/skbuff.c:658 __netdev_alloc_skb+0x105/0xa10 net/core/skbuff.c:732 netdev_alloc_skb include/linux/skbuff.h:3413 [inline] dev_alloc_skb include/linux/skbuff.h:3426 [inline] __ieee80211_beacon_get+0x9a7/0x15e0 net/mac80211/tx.c:5475 ieee80211_beacon_get_tim+0xb7/0x330 net/mac80211/tx.c:5597 ieee80211_beacon_get include/net/mac80211.h:5648 [inline] mac80211_hwsim_beacon_tx+0x3a2/0x860 drivers/net/wireless/virtual/mac80211_hwsim.c:2313 __iterate_interfaces+0x297/0x570 net/mac80211/util.c:761 ieee80211_iterate_active_interfaces_atomic+0xd8/0x170 net/mac80211/util.c:797 mac80211_hwsim_beacon+0xd4/0x1f0 drivers/net/wireless/virtual/mac80211_hwsim.c:2347 __run_hrtimer kernel/time/hrtimer.c:1761 [inline] __hrtimer_run_queues+0x5a6/0xd40 kernel/time/hrtimer.c:1825 hrtimer_run_softirq+0x19a/0x2c0 kernel/time/hrtimer.c:1842 handle_softirqs+0x2d6/0x9b0 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xfb/0x220 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 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:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x1bac/0x2d40 kernel/smp.c:885 Code: 03 84 c0 75 7e 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 b8 e2 0b 00 41 83 e4 01 4c 8b 64 24 68 75 07 e8 68 de 0b 00 eb 41 f3 90 <48> b8 00 00 00 00 00 fc ff df 0f b6 04 03 84 c0 75 11 41 f7 45 00 RSP: 0018:ffffc9000be774c0 EFLAGS: 00000246 RAX: ffffffff81b7661d RBX: 1ffff110170c8219 RCX: 0000000000080000 RDX: ffffc9000cdf3000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc9000be776c0 R08: ffffffff81b765e8 R09: 1ffffffff20bd6ce R10: dffffc0000000000 R11: fffffbfff20bd6cf R12: ffff8880b873ab88 R13: ffff8880b86410c8 R14: ffff8880b873ab80 R15: 0000000000000000 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline] flush_tlb_multi arch/x86/mm/tlb.c:1275 [inline] flush_tlb_mm_range+0xb8d/0x13f0 arch/x86/mm/tlb.c:1365 dup_mmap kernel/fork.c:765 [inline] dup_mm kernel/fork.c:1734 [inline] copy_mm+0x19de/0x22c0 kernel/fork.c:1786 copy_process+0x17de/0x3d10 kernel/fork.c:2429 kernel_clone+0x227/0x880 kernel/fork.c:2844 __do_sys_clone kernel/fork.c:2987 [inline] __se_sys_clone kernel/fork.c:2971 [inline] __x64_sys_clone+0x268/0x2e0 kernel/fork.c:2971 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff68cb8d169 Code: ff ff c3 66 2e 0f 1f 84 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 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ff68da0dfe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007ff68cda5fa0 RCX: 00007ff68cb8d169 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000011 RBP: 00007ff68cc0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000001 R14: 00007ff68cda5fa0 R15: 00007ffedc39a548