watchdog: BUG: soft lockup - CPU#0 stuck for 122s! [syz.6.95:6682] Modules linked in: irq event stamp: 18380763 hardirqs last enabled at (18380762): [] irqentry_exit+0x74/0x90 kernel/entry/common.c:357 hardirqs last disabled at (18380763): [] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1049 softirqs last enabled at (18076872): [] __do_softirq kernel/softirq.c:613 [inline] softirqs last enabled at (18076872): [] invoke_softirq kernel/softirq.c:453 [inline] softirqs last enabled at (18076872): [] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 softirqs last disabled at (18076875): [] __do_softirq kernel/softirq.c:613 [inline] softirqs last disabled at (18076875): [] invoke_softirq kernel/softirq.c:453 [inline] softirqs last disabled at (18076875): [] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 CPU: 0 UID: 0 PID: 6682 Comm: syz.6.95 Not tainted 6.15.0-rc4-syzkaller-g9325d53fe9ad #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:check_preemption_disabled+0x1/0x120 lib/smp_processor_id.c:13 Code: 40 d0 c1 8b 48 c7 c6 80 d0 c1 8b eb 1c 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 <41> 57 41 56 53 48 83 ec 10 65 48 8b 05 4e 3e 1f 07 48 89 44 24 08 RSP: 0018:ffffc900000072c0 EFLAGS: 00000203 RAX: 0000000000000000 RBX: ffffffff90b35101 RCX: 72068a37821f6f00 RDX: ffffc90000007468 RSI: ffffffff8bc1d080 RDI: ffffffff8bc1d040 RBP: dffffc0000000000 R08: ffffc9000505e898 R09: 0000000000000000 R10: ffffc90000007478 R11: fffff52000000e91 R12: ffffc9000505e898 R13: ffffffff817199f5 R14: ffffffff8df3b860 R15: ffffffff817199f5 FS: 0000000000000000(0000) GS:ffff8881260ca000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f11c7c6e068 CR3: 0000000066790000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:736 trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0x4b/0x3e0 kernel/locking/lockdep.c:5877 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] class_rcu_destructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2398 [inline] slab_free mm/slub.c:4656 [inline] kmem_cache_free+0x192/0x3f0 mm/slub.c:4758 kfree_skb_reason include/linux/skbuff.h:1279 [inline] kfree_skb include/linux/skbuff.h:1288 [inline] ip6_mc_input+0x9c3/0xbe0 net/ipv6/ip6_input.c:591 NF_HOOK+0x309/0x3a0 include/linux/netfilter.h:314 __netif_receive_skb_one_core net/core/dev.c:5887 [inline] __netif_receive_skb+0xd3/0x380 net/core/dev.c:6000 process_backlog+0x60e/0x14f0 net/core/dev.c:6352 __napi_poll+0xc4/0x480 net/core/dev.c:7324 napi_poll net/core/dev.c:7388 [inline] net_rx_action+0x6ea/0xdf0 net/core/dev.c:7510 handle_softirqs+0x283/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 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:__schedule+0x0/0x4cd0 kernel/sched/core.c:6646 Code: cb f6 45 89 f8 89 d9 48 8b 5c 24 08 e9 ee fe ff ff cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 RSP: 0018:ffffc9000505e958 EFLAGS: 00000286 RAX: 72068a37821f6f00 RBX: 0000000000000000 RCX: 72068a37821f6f00 RDX: 0000000000000007 RSI: ffffffff8d74a79b RDI: 0000000000000001 RBP: ffffc9000505ea00 R08: ffffffff8f7ed277 R09: 1ffffffff1efda4e R10: dffffc0000000000 R11: fffffbfff1efda4f R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92000a0bd2c preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7090 irqentry_exit+0x6f/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:26 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:109 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:127 [inline] RIP: 0010:rcu_read_unlock_special+0xdf/0x4c0 kernel/rcu/tree_plugin.h:649 Code: 00 0f 85 65 03 00 00 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 49 89 ff 48 c7 84 24 80 00 00 00 00 00 00 00 <9c> 8f 84 24 80 00 00 00 4c 8b a4 24 80 00 00 00 fa 41 f7 c4 00 02 RSP: 0018:ffffc9000505eac0 EFLAGS: 00000246 RAX: f2f2f200f1f1f1f1 RBX: 1ffff92000a0bd60 RCX: 72068a37821f6f00 RDX: 0000000000000001 RSI: ffffffff8d93592f RDI: ffff888024cb1e00 RBP: ffffc9000505ebb8 R08: ffffc9000505fcb8 R09: 0000000000000000 R10: ffffc9000505ed18 R11: fffff52000a0bda5 R12: 1ffff11004996448 R13: dffffc0000000000 R14: 0000000080000000 R15: ffff888024cb1e00 __rcu_read_unlock+0x84/0xe0 kernel/rcu/tree_plugin.h:438 rcu_read_unlock include/linux/rcupdate.h:873 [inline] class_rcu_destructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0x19ae/0x2390 arch/x86/kernel/unwind_orc.c:680 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 save_stack+0xf7/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1262 [inline] free_unref_folios+0xb81/0x14a0 mm/page_alloc.c:2782 folios_put_refs+0x559/0x640 mm/swap.c:992 free_pages_and_swap_cache+0x4be/0x520 mm/swap_state.c:270 __tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline] tlb_batch_pages_flush mm/mmu_gather.c:149 [inline] tlb_flush_mmu_free mm/mmu_gather.c:397 [inline] tlb_flush_mmu+0x3a0/0x680 mm/mmu_gather.c:404 zap_pte_range mm/memory.c:1770 [inline] zap_pmd_range mm/memory.c:1823 [inline] zap_pud_range mm/memory.c:1852 [inline] zap_p4d_range mm/memory.c:1873 [inline] unmap_page_range+0x37fd/0x4210 mm/memory.c:1894 unmap_vmas+0x25d/0x3c0 mm/memory.c:1984 exit_mmap+0x245/0xba0 mm/mmap.c:1284 __mmput+0x118/0x420 kernel/fork.c:1379 exit_mm+0x1da/0x2c0 kernel/exit.c:589 do_exit+0x859/0x2550 kernel/exit.c:940 do_group_exit+0x21c/0x2d0 kernel/exit.c:1102 get_signal+0x125e/0x1310 kernel/signal.c:3034 arch_do_signal_or_restart+0x95/0x780 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] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x8b/0x120 kernel/entry/common.c:218 do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0ef4d8e969 Code: Unable to access opcode bytes at 0x7f0ef4d8e93f. RSP: 002b:00007f0ef5bfa038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: 0000000000000006 RBX: 00007f0ef4fb6080 RCX: 00007f0ef4d8e969 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000500 RBP: 00007f0ef4e10ab1 R08: 0000000000000009 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f0ef4fb6080 R15: 00007ffe32811a48 Sending NMI from CPU 0 to CPUs 1: rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 6719 Comm: syz.8.102 Not tainted 6.15.0-rc4-syzkaller-g9325d53fe9ad #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:409 Code: e8 9e 1b 82 fc 44 89 f9 d3 e3 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 0f 35 e4 fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f c3 cc cc cc cc cc 44 89 f9 80 e1 07 RSP: 0018:ffffc90000a07d78 EFLAGS: 00000006 RAX: 1ffffffff3369b05 RBX: 00000000000003f9 RCX: 0000000000000000 RDX: 00000000000003f9 RSI: 0000000000000000 RDI: 0000000000000020 RBP: ffffc90000a07f50 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: ffffffff853da2e0 R12: dffffc0000000000 R13: dffffc0000000000 R14: ffffffff99b4dbc0 R15: 0000000000000000 FS: 00007f3f88bdf6c0(0000) GS:ffff8881261ca000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f96f99b6038 CR3: 000000002b5fc000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: serial_port_in include/linux/serial_core.h:791 [inline] serial8250_console_write+0x581/0x1ba0 drivers/tty/serial/8250/8250_port.c:3420 console_emit_next_record kernel/printk/printk.c:3138 [inline] console_flush_all+0x725/0xc40 kernel/printk/printk.c:3226 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0xc4/0x270 kernel/printk/printk.c:3325 vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450 _printk+0xcf/0x120 kernel/printk/printk.c:2475 print_other_cpu_stall+0x189/0x1370 kernel/rcu/tree_stall.h:598 check_cpu_stall kernel/rcu/tree_stall.h:795 [inline] rcu_pending kernel/rcu/tree.c:3630 [inline] rcu_sched_clock_irq+0x9cb/0x1080 kernel/rcu/tree.c:2669 update_process_times+0x23c/0x2f0 kernel/time/timer.c:2515 tick_sched_handle kernel/time/tick-sched.c:276 [inline] tick_nohz_handler+0x39a/0x520 kernel/time/tick-sched.c:297 __run_hrtimer kernel/time/hrtimer.c:1761 [inline] __hrtimer_run_queues+0x4dd/0xc60 kernel/time/hrtimer.c:1825 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x108/0x410 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:ieee80211_prepare_and_rx_handle+0x0/0x6200 net/mac80211/rx.c:4971 Code: 38 c1 0f 8c 27 fa ff ff e8 5d 6d 4e f7 e9 1d fa ff ff 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 RSP: 0018:ffffc90000a089f8 EFLAGS: 00000282 RAX: 1ffff9200014115c RBX: ffff8880734d28c8 RCX: dffffc0000000000 RDX: 0000000000000001 RSI: ffff888011e283c0 RDI: ffffc90000a08ac0 RBP: ffffc90000a08c10 R08: 0000000000000000 R09: 000000000000000c R10: 000000000000000c R11: 0000000000000100 R12: dffffc0000000000 R13: ffff888011e283c0 R14: ffff8880734d28c8 R15: 0000000000000000 __ieee80211_rx_handle_packet net/mac80211/rx.c:5281 [inline] ieee80211_rx_list+0x2499/0x2d80 net/mac80211/rx.c:5416 ieee80211_rx_napi+0x1a8/0x3d0 net/mac80211/rx.c:5439 ieee80211_rx include/net/mac80211.h:5179 [inline] ieee80211_handle_queued_frames+0xe8/0x1f0 net/mac80211/main.c:441 tasklet_action_common+0x369/0x580 kernel/softirq.c:829 handle_softirqs+0x283/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 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:preempt_schedule_irq+0xb0/0x150 kernel/sched/core.c:7090 Code: 24 20 f6 44 24 21 02 74 0c 90 0f 0b 48 f7 03 08 00 00 00 74 64 bf 01 00 00 00 e8 eb 93 39 f6 e8 86 13 70 f6 fb bf 01 00 00 00 4b ab ff ff 48 c7 44 24 40 00 00 00 00 9c 8f 44 24 40 8b 44 24 RSP: 0018:ffffc90003d3ed00 EFLAGS: 00000286 RAX: 4bf27c2fc3c40700 RBX: 0000000000000000 RCX: 4bf27c2fc3c40700 RDX: 0000000000000006 RSI: ffffffff8d74a79b RDI: 0000000000000001 RBP: ffffc90003d3edb0 R08: ffffffff8f7ed277 R09: 1ffffffff1efda4e R10: dffffc0000000000 R11: fffffbfff1efda4f R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff920007a7da0 irqentry_exit+0x6f/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:unwind_next_frame+0x4f3/0x2390 arch/x86/kernel/unwind_orc.c:512 Code: f0 48 c1 e8 03 48 89 44 24 40 0f b6 04 28 84 c0 48 89 54 24 08 48 89 34 24 0f 85 4d 18 00 00 4c 89 e0 48 c1 e8 03 0f b6 04 28 <84> c0 0f 85 63 18 00 00 0f b7 1e c1 eb 0b 80 e3 01 48 8b 44 24 28 RSP: 0018:ffffc90003d3ee78 EFLAGS: 00000a07 RAX: 0000000000000000 RBX: ffffffff8f9aae2c RCX: ffffffff8f9aae30 RDX: ffffffff9019a238 RSI: ffffffff9019a23c RDI: ffffffff8bc1d040 RBP: dffffc0000000000 R08: 0000000000000009 R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff817199f5 R12: ffffffff9019a23d R13: ffffc90003d3ef98 R14: ffffc90003d3ef48 R15: ffffffff817199f5 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4372 kmalloc_noprof include/linux/slab.h:905 [inline] genl_dumpit_info_alloc net/netlink/genetlink.c:915 [inline] genl_start+0x1c9/0x6c0 net/netlink/genetlink.c:986 __netlink_dump_start+0x466/0x7e0 net/netlink/af_netlink.c:2415 genl_family_rcv_msg_dumpit+0x1e7/0x2c0 net/netlink/genetlink.c:1076 genl_family_rcv_msg net/netlink/genetlink.c:1192 [inline] genl_rcv_msg+0x5da/0x790 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x219/0x490 net/netlink/af_netlink.c:2534 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x758/0x8d0 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:727 ____sys_sendmsg+0x505/0x830 net/socket.c:2566 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2620 __sys_sendmsg net/socket.c:2652 [inline] __do_sys_sendmsg net/socket.c:2657 [inline] __se_sys_sendmsg net/socket.c:2655 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2655 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3f87d8e969 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:00007f3f88bdf038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f3f87fb5fa0 RCX: 00007f3f87d8e969 RDX: 0000000000000000 RSI: 0000200000000040 RDI: 0000000000000004 RBP: 00007f3f87e10ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f3f87fb5fa0 R15: 00007fffdf6fff58