rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (0 ticks this GP) idle=2b9/1/0x4000000000000000 softirq=60460/60460 fqs=0 (detected by 1, t=10502 jiffies, g=76297, q=1215) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 18617 Comm: syz.2.13146 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:asm_sysvec_irq_work+0x0/0x20 arch/x86/include/asm/idtentry.h:707 Code: e9 a5 03 00 00 90 90 90 90 90 0f 01 ca fc 6a ff e8 a5 02 00 00 48 89 c4 48 89 e7 e8 8a 41 e9 ff e9 85 03 00 00 90 90 90 90 90 <0f> 01 ca fc 6a ff e8 85 02 00 00 48 89 c4 48 89 e7 e8 5a 46 e9 ff RSP: 0018:ffffc90000007ad8 EFLAGS: 00000006 RAX: e0f7fb7263cad900 RBX: 1ffff92000000f64 RCX: e0f7fb7263cad900 RDX: dffffc0000000000 RSI: ffffffff8a0b1c60 RDI: ffffffff8a59e580 RBP: ffffc90000007be0 R08: dffffc0000000000 R09: ffffed1017207662 R10: ffffed1017207662 R11: 1ffff11017207661 R12: ffffffff8c120c00 R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001 FS: 0000555555e41500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b34a63fff CR3: 0000000017636000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: RIP: 0010:rcu_read_unlock_special+0x84/0x480 kernel/rcu/tree_plugin.h:674 Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 ed 11 9e 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b RSP: 0018:ffffc90000007b00 EFLAGS: 00000206 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422 rcu_read_unlock include/linux/rcupdate.h:772 [inline] ieee80211_rx_napi+0x1f4/0x360 net/mac80211/rx.c:5010 ieee80211_rx include/net/mac80211.h:4573 [inline] ieee80211_handle_queued_frames+0x105/0x1b0 net/mac80211/main.c:237 tasklet_action_common+0x298/0x400 kernel/softirq.c:806 handle_softirqs+0x328/0x820 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:preempt_count_sub+0x35/0x160 kernel/sched/core.c:5536 Code: df 48 c7 c0 80 4f 0c 96 48 c1 e8 03 0f b6 04 18 84 c0 0f 85 bd 00 00 00 83 3d 26 dd ba 14 00 75 25 65 8b 05 65 fd b0 7e 89 c1 <81> e1 ff ff ff 7f 39 cf 7f 25 81 ff ff 00 00 00 0f 93 c1 84 c0 0f RSP: 0018:ffffc90003e4fdb8 EFLAGS: 00000246 RAX: 0000000080000001 RBX: dffffc0000000000 RCX: 0000000080000001 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000001 RBP: 1ffff1100f8a760f R08: dffffc0000000000 R09: ffffed100d26e721 R10: ffffed100d26e721 R11: 1ffff1100d26e720 R12: 000000000000000f R13: ffff88807c53b078 R14: ffff888069373840 R15: fffffffffffffff7 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock+0x24/0x40 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:404 [inline] pick_file+0x18c/0x220 fs/file.c:639 __range_close fs/file.c:689 [inline] __close_range+0x1cd/0x4d0 fs/file.c:747 __do_sys_close_range fs/open.c:1408 [inline] __se_sys_close_range fs/open.c:1405 [inline] __x64_sys_close_range+0x76/0x80 fs/open.c:1405 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7ff77a6c1749 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:00007ffd64602d38 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: ffffffffffffffda RBX: 00000000000a64e2 RCX: 00007ff77a6c1749 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000001 R09: 000000036460302f R10: 0000001b33e20000 R11: 0000000000000246 R12: 00007ff77a917fac R13: 00007ff77a917fa0 R14: ffffffffffffffff R15: 0000000000000003 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g76297 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=19684 rcu: rcu_preempt kthread starved for 10502 jiffies! g76297 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27528 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 18617 Comm: syz.2.13146 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:find_held_lock kernel/locking/lockdep.c:-1 [inline] RIP: 0010:__lock_release kernel/locking/lockdep.c:5300 [inline] RIP: 0010:lock_release+0x1fc/0x870 kernel/locking/lockdep.c:5643 Code: 89 4c 24 28 83 f9 32 0f 83 ca 04 00 00 4b 8d 04 b6 4c 8d 24 c3 48 89 c3 4c 89 e7 48 8b 74 24 08 e8 69 f5 4c 08 44 89 7c 24 3c <44> 89 fa 85 c0 0f 84 d2 01 00 00 4d 85 e4 0f 84 0b 03 00 00 4d 8d RSP: 0018:ffffc90000007260 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 000000000000000a RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff8c11c760 RDI: ffff888022fee480 RBP: ffffc90000007370 R08: dffffc0000000000 R09: fffffbfff1ad33a6 R10: fffffbfff1ad33a6 R11: 1ffffffff1ad33a5 R12: ffff888022fee480 R13: dffffc0000000000 R14: 0000000000000002 R15: 0000000000000002 FS: 0000555555e41500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b34a63fff CR3: 0000000017636000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __perf_output_begin kernel/events/ring_buffer.c:262 [inline] perf_output_begin_forward+0x793/0xa30 kernel/events/ring_buffer.c:271 __perf_event_output kernel/events/core.c:7804 [inline] perf_event_output_forward+0x15c/0x280 kernel/events/core.c:7822 __perf_event_overflow+0x364/0x530 kernel/events/core.c:9515 perf_tp_event+0x32c/0xb50 kernel/events/core.c:10047 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10021 perf_trace_preemptirq_template+0x2be/0x380 include/trace/events/preemptirq.h:14 trace_irq_enable_rcuidle+0x108/0x180 include/trace/events/preemptirq.h:40 trace_hardirqs_on+0x57/0x80 kernel/trace/trace_preemptirq.c:44 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713 RIP: 0010:rcu_read_unlock_special+0x84/0x480 kernel/rcu/tree_plugin.h:674 Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 ed 11 9e 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b RSP: 0018:ffffc90000007b00 EFLAGS: 00000206 RAX: e0f7fb7263cad900 RBX: 1ffff92000000f64 RCX: e0f7fb7263cad900 RDX: dffffc0000000000 RSI: ffffffff8a0b1c60 RDI: ffffffff8a59e580 RBP: ffffc90000007be0 R08: dffffc0000000000 R09: ffffed1017207662 R10: ffffed1017207662 R11: 1ffff11017207661 R12: ffffffff8c120c00 R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422 rcu_read_unlock include/linux/rcupdate.h:772 [inline] ieee80211_rx_napi+0x1f4/0x360 net/mac80211/rx.c:5010 ieee80211_rx include/net/mac80211.h:4573 [inline] ieee80211_handle_queued_frames+0x105/0x1b0 net/mac80211/main.c:237 tasklet_action_common+0x298/0x400 kernel/softirq.c:806 handle_softirqs+0x328/0x820 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:preempt_count_sub+0x35/0x160 kernel/sched/core.c:5536 Code: df 48 c7 c0 80 4f 0c 96 48 c1 e8 03 0f b6 04 18 84 c0 0f 85 bd 00 00 00 83 3d 26 dd ba 14 00 75 25 65 8b 05 65 fd b0 7e 89 c1 <81> e1 ff ff ff 7f 39 cf 7f 25 81 ff ff 00 00 00 0f 93 c1 84 c0 0f RSP: 0018:ffffc90003e4fdb8 EFLAGS: 00000246 RAX: 0000000080000001 RBX: dffffc0000000000 RCX: 0000000080000001 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000001 RBP: 1ffff1100f8a760f R08: dffffc0000000000 R09: ffffed100d26e721 R10: ffffed100d26e721 R11: 1ffff1100d26e720 R12: 000000000000000f R13: ffff88807c53b078 R14: ffff888069373840 R15: fffffffffffffff7 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock+0x24/0x40 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:404 [inline] pick_file+0x18c/0x220 fs/file.c:639 __range_close fs/file.c:689 [inline] __close_range+0x1cd/0x4d0 fs/file.c:747 __do_sys_close_range fs/open.c:1408 [inline] __se_sys_close_range fs/open.c:1405 [inline] __x64_sys_close_range+0x76/0x80 fs/open.c:1405 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7ff77a6c1749 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:00007ffd64602d38 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: ffffffffffffffda RBX: 00000000000a64e2 RCX: 00007ff77a6c1749 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000001 R09: 000000036460302f R10: 0000001b33e20000 R11: 0000000000000246 R12: 00007ff77a917fac R13: 00007ff77a917fa0 R14: ffffffffffffffff R15: 0000000000000003