rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (5 ticks this GP) idle=21b/1/0x4000000000000002 softirq=89609/89609 fqs=0 (detected by 1, t=10502 jiffies, g=121245, q=1811) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 32224 Comm: syz.8.5821 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 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 7a 3c dc 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 4a 41 dc ff RSP: 0018:ffffc90000007ad8 EFLAGS: 00000006 RAX: a808d330fdd1ef00 RBX: 1ffff92000000f64 RCX: a808d330fdd1ef00 RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: ffffffff8a79f980 RBP: ffffc90000007bd8 R08: ffff8880b903b30b R09: 1ffff11017207661 R10: dffffc0000000000 R11: ffffed1017207662 R12: ffffffff8c322f00 R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001 FS: 00007f3c63e566c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000001000 CR3: 0000000075656000 CR4: 00000000003506f0 DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000200000000300 DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: RIP: 0010:rcu_read_unlock_special+0x7f/0x4a0 kernel/rcu/tree_plugin.h:674 Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 12 f2 9c 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08 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_iterate_active_interfaces_atomic+0x132/0x140 net/mac80211/util.c:831 mac80211_hwsim_beacon+0x9b/0x180 drivers/net/wireless/mac80211_hwsim.c:1865 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x4f2/0xb70 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x176/0x240 kernel/time/hrtimer.c:1766 handle_softirqs+0x339/0x830 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x13b/0x230 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:put_cpu_partial+0x15e/0x190 mm/slub.c:2591 Code: 00 00 48 3b 44 24 08 75 4d 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 3f aa fe 07 41 f7 c5 00 02 00 00 74 c3 fb 4d 85 ff <75> c2 eb cb 48 c7 c7 d0 21 3f 8c 4c 89 e6 e8 5f 34 46 02 e9 e5 fe RSP: 0018:ffffc90002eef7e8 EFLAGS: 00000286 RAX: a808d330fdd1ef00 RBX: ffff888016c42140 RCX: a808d330fdd1ef00 RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: ffffffff8a79f980 RBP: 0000000000000001 R08: ffff8880b903b30b R09: 1ffff11017207661 R10: dffffc0000000000 R11: ffffed1017207662 R12: 0000000000000000 R13: 0000000000000286 R14: ffff8880b903e000 R15: ffffea0000ded200 qlist_free_all+0x35/0x90 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x150/0x160 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x2f/0xd0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3225 [inline] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc_trace+0x103/0x2a0 mm/slub.c:3250 kmalloc include/linux/slab.h:607 [inline] kzalloc include/linux/slab.h:738 [inline] bpf_prog_alloc_no_stats+0xac/0x2c0 kernel/bpf/core.c:94 bpf_prog_alloc+0x1a/0x1e0 kernel/bpf/core.c:124 bpf_prog_load+0x7c6/0x1510 kernel/bpf/syscall.c:2301 __sys_bpf+0x532/0x6f0 kernel/bpf/syscall.c:4657 __do_sys_bpf kernel/bpf/syscall.c:4761 [inline] __se_sys_bpf kernel/bpf/syscall.c:4759 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:4759 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: 0033:0x7f3c65c3e819 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f3c63e56028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f3c65eb8180 RCX: 00007f3c65c3e819 RDX: 0000000000000048 RSI: 0000200000000200 RDI: 0000000000000005 RBP: 00007f3c65cd4c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3c65eb8218 R14: 00007f3c65eb8180 R15: 00007fff269225f8 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g121245 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=88929 rcu: rcu_preempt kthread starved for 10502 jiffies! g121245 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:27280 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2117 rcu_gp_fqs_loop+0x2be/0x11d0 kernel/rcu/tree.c:1972 rcu_gp_kthread+0x9b/0x370 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: 32224 Comm: syz.8.5821 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x7e/0x80 kernel/kcov.c:295 Code: 8d 50 28 4d 39 ca 77 22 89 ff 89 f6 4a c7 44 02 08 05 00 00 00 4a 89 7c 02 10 4a 89 74 02 18 4a 89 44 02 20 48 ff c1 48 89 0a 90 48 8b 04 24 65 48 8b 0d c4 4a 89 7e 65 8b 15 c5 4a 89 7e 81 RSP: 0018:ffffc900000078f8 EFLAGS: 00000046 RAX: ffffffff8180fb26 RBX: 0000000000000014 RCX: ffff88807e118000 RDX: 0000000000000100 RSI: 0000000000000001 RDI: 0000000000000005 RBP: 0000000000000001 R08: ffff8880b903b30b R09: 1ffff11017207661 R10: dffffc0000000000 R11: ffffed1017207662 R12: ffffe8ffffc428d0 R13: dffffc0000000000 R14: ffffc90000007980 R15: 0000000000000001 FS: 00007f3c63e566c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000001000 CR3: 0000000075656000 CR4: 00000000003506f0 DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000200000000300 DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: perf_trace_buf_alloc+0x96/0x300 kernel/trace/trace_event_perf.c:419 perf_trace_preemptirq_template+0x180/0x360 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+0x7f/0x4a0 kernel/rcu/tree_plugin.h:674 Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 12 f2 9c 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08 RSP: 0018:ffffc90000007b00 EFLAGS: 00000206 RAX: a808d330fdd1ef00 RBX: 1ffff92000000f64 RCX: a808d330fdd1ef00 RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: ffffffff8a79f980 RBP: ffffc90000007bd8 R08: ffff8880b903b30b R09: 1ffff11017207661 R10: dffffc0000000000 R11: ffffed1017207662 R12: ffffffff8c322f00 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_iterate_active_interfaces_atomic+0x132/0x140 net/mac80211/util.c:831 mac80211_hwsim_beacon+0x9b/0x180 drivers/net/wireless/mac80211_hwsim.c:1865 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x4f2/0xb70 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x176/0x240 kernel/time/hrtimer.c:1766 handle_softirqs+0x339/0x830 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x13b/0x230 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:put_cpu_partial+0x15e/0x190 mm/slub.c:2591 Code: 00 00 48 3b 44 24 08 75 4d 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 3f aa fe 07 41 f7 c5 00 02 00 00 74 c3 fb 4d 85 ff <75> c2 eb cb 48 c7 c7 d0 21 3f 8c 4c 89 e6 e8 5f 34 46 02 e9 e5 fe RSP: 0018:ffffc90002eef7e8 EFLAGS: 00000286 RAX: a808d330fdd1ef00 RBX: ffff888016c42140 RCX: a808d330fdd1ef00 RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: ffffffff8a79f980 RBP: 0000000000000001 R08: ffff8880b903b30b R09: 1ffff11017207661 R10: dffffc0000000000 R11: ffffed1017207662 R12: 0000000000000000 R13: 0000000000000286 R14: ffff8880b903e000 R15: ffffea0000ded200 qlist_free_all+0x35/0x90 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x150/0x160 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x2f/0xd0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3225 [inline] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc_trace+0x103/0x2a0 mm/slub.c:3250 kmalloc include/linux/slab.h:607 [inline] kzalloc include/linux/slab.h:738 [inline] bpf_prog_alloc_no_stats+0xac/0x2c0 kernel/bpf/core.c:94 bpf_prog_alloc+0x1a/0x1e0 kernel/bpf/core.c:124 bpf_prog_load+0x7c6/0x1510 kernel/bpf/syscall.c:2301 __sys_bpf+0x532/0x6f0 kernel/bpf/syscall.c:4657 __do_sys_bpf kernel/bpf/syscall.c:4761 [inline] __se_sys_bpf kernel/bpf/syscall.c:4759 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:4759 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: 0033:0x7f3c65c3e819 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f3c63e56028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f3c65eb8180 RCX: 00007f3c65c3e819 RDX: 0000000000000048 RSI: 0000200000000200 RDI: 0000000000000005 RBP: 00007f3c65cd4c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3c65eb8218 R14: 00007f3c65eb8180 R15: 00007fff269225f8