watchdog: BUG: soft lockup - CPU#0 stuck for 143s! [syz.6.148:6851] Modules linked in: irq event stamp: 18655723 hardirqs last enabled at (18655722): [] irqentry_exit+0x74/0x90 kernel/entry/common.c:357 hardirqs last disabled at (18655723): [] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1049 softirqs last enabled at (14257084): [] __do_softirq kernel/softirq.c:613 [inline] softirqs last enabled at (14257084): [] invoke_softirq kernel/softirq.c:453 [inline] softirqs last enabled at (14257084): [] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 softirqs last disabled at (14257087): [] __do_softirq kernel/softirq.c:613 [inline] softirqs last disabled at (14257087): [] invoke_softirq kernel/softirq.c:453 [inline] softirqs last disabled at (14257087): [] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 CPU: 0 UID: 0 PID: 6851 Comm: syz.6.148 Not tainted 6.15.0-rc4-syzkaller-gdb22b1382b96 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:debug_check_no_obj_freed+0x0/0x470 lib/debugobjects.c:1127 Code: 80 c1 03 38 c1 0f 8c 2d ff ff ff 4c 89 ef e8 d7 5e 63 fd e9 20 ff ff ff 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <66> 0f 1f 00 55 41 57 41 56 41 55 41 54 53 48 81 ec 88 00 00 00 65 RSP: 0018:ffffc90000007808 EFLAGS: 00000286 RAX: 4bc7bfc7a821b700 RBX: 0000000000000008 RCX: ffff888034438e01 RDX: 0000000000000002 RSI: 0000000000008000 RDI: ffff8880683f0000 RBP: 0005088000000000 R08: ffffffff8f7ed577 R09: 1ffffffff1efdaae R10: dffffc0000000000 R11: fffffbfff1efdaaf R12: ffffea0001a0fc00 R13: ffff8880683f0000 R14: 0000000000008000 R15: 0000000000000003 FS: 00007f5c76a556c0(0000) GS:ffff8881260c9000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5c76a34d58 CR3: 000000006ced4000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: free_pages_prepare mm/page_alloc.c:1269 [inline] __free_frozen_pages+0x403/0xcd0 mm/page_alloc.c:2725 __folio_put+0x21b/0x2c0 mm/swap.c:112 skb_page_unref include/linux/skbuff_ref.h:43 [inline] __skb_frag_unref include/linux/skbuff_ref.h:56 [inline] skb_release_data+0x4df/0x890 net/core/skbuff.c:1091 skb_release_all net/core/skbuff.c:1162 [inline] __kfree_skb+0x55/0x70 net/core/skbuff.c:1176 tcp_write_queue_purge+0x143/0x2f0 net/ipv4/tcp.c:3288 tcp_done_with_error+0x43/0xd0 net/ipv4/tcp_input.c:4545 tcp_write_err net/ipv4/tcp_timer.c:77 [inline] tcp_write_timeout net/ipv4/tcp_timer.c:294 [inline] tcp_retransmit_timer+0x1456/0x3200 net/ipv4/tcp_timer.c:600 tcp_write_timer+0x162/0x2e0 net/ipv4/tcp_timer.c:738 call_timer_fn+0x17b/0x5f0 kernel/time/timer.c:1789 expire_timers kernel/time/timer.c:1840 [inline] __run_timers kernel/time/timer.c:2414 [inline] __run_timer_base+0x61a/0x860 kernel/time/timer.c:2426 run_timer_base kernel/time/timer.c:2435 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2445 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_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0xa3/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:738 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 83 39 f6 e8 86 03 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:ffffc9000c4c7b80 EFLAGS: 00000282 RAX: 4bc7bfc7a821b700 RBX: 0000000000000000 RCX: 4bc7bfc7a821b700 RDX: 0000000000000000 RSI: ffffffff8d74afe2 RDI: 0000000000000001 RBP: ffffc9000c4c7c30 R08: ffffffff8f7ed577 R09: 1ffffffff1efdaae R10: dffffc0000000000 R11: fffffbfff1efdaaf R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92001898f70 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:check_kcov_mode kernel/kcov.c:185 [inline] RIP: 0010:write_comp_data kernel/kcov.c:246 [inline] RIP: 0010:__sanitizer_cov_trace_switch+0xb3/0x130 kernel/kcov.c:351 Code: 77 4e 8b 54 ce 10 65 44 8b 1d 49 ab b5 10 41 81 e3 00 01 ff 00 74 13 41 81 fb 00 01 00 00 75 d9 41 83 b8 3c 16 00 00 00 74 cf <45> 8b 98 18 16 00 00 41 83 fb 03 75 c2 4d 8b 98 20 16 00 00 45 8b RSP: 0018:ffffc9000c4c7cf8 EFLAGS: 00000246 RAX: 000000000000000d RBX: 0000000000000000 RCX: 0000000000000005 RDX: ffffffff81b35faa RSI: ffffffff8df6bf20 RDI: 0000000000000001 RBP: ffffc9000c4c7de8 R08: ffff88802d25bc00 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000000 R12: ffffc9000c4c7d80 R13: 0000000000000001 R14: 1ffff92001898fac R15: 0000000000000000 do_futex+0xea/0x420 kernel/futex/syscalls.c:97 __do_sys_futex kernel/futex/syscalls.c:179 [inline] __se_sys_futex+0x36f/0x400 kernel/futex/syscalls.c:160 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: 0033:0x7f5c75b8e969 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:00007f5c76a550e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007f5c75db5fa8 RCX: 00007f5c75b8e969 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f5c75db5fac RBP: 00007f5c75db5fa0 R08: 7fffffffffffffff R09: 0000000000000000 R10: 000000000000000b R11: 0000000000000246 R12: 00007f5c75db5fac R13: 0000000000000000 R14: 00007ffe4ab51d20 R15: 00007ffe4ab51e08 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 6855 Comm: syz.5.150 Not tainted 6.15.0-rc4-syzkaller-gdb22b1382b96 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:strlen+0x2e/0x70 lib/string.c:420 Code: 41 57 41 56 41 54 53 48 c7 c0 ff ff ff ff 49 be 00 00 00 00 00 fc ff df 48 89 fb 49 89 c7 48 89 d8 48 c1 e8 03 42 0f b6 04 30 <84> c0 75 11 48 ff c3 49 8d 47 01 42 80 7c 3f 01 00 75 de eb 19 89 RSP: 0018:ffffc90000a082d8 EFLAGS: 00000a02 RAX: 0000000000000000 RBX: ffffffff8b6bb961 RCX: 58399c5a2a4cfd00 RDX: ffffffff817199f5 RSI: ffffffff8df3b860 RDI: ffffffff8b6bb960 RBP: ffffc90000a08400 R08: ffffc90000a08f50 R09: 0000000000000000 R10: ffffc90000a08598 R11: fffff520001410b5 R12: 1ffff92000141068 R13: ffffffff817199f5 R14: dffffc0000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881261c9000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4f4f8f4020 CR3: 00000000320ec000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: _Z16__fortify_strlenPKcU25pass_dynamic_object_size1 include/linux/fortify-string.h:268 [inline] trace_event_get_offsets_lock include/trace/events/lock.h:50 [inline] do_perf_trace_lock include/trace/events/lock.h:50 [inline] perf_trace_lock+0xc2/0x3b0 include/trace/events/lock.h:50 __do_trace_lock_release include/trace/events/lock.h:69 [inline] trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0x3b2/0x3e0 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 skb_kfree_head net/core/skbuff.c:1056 [inline] skb_free_head net/core/skbuff.c:1070 [inline] skb_release_data+0x670/0x890 net/core/skbuff.c:1097 skb_release_all net/core/skbuff.c:1162 [inline] __kfree_skb+0x55/0x70 net/core/skbuff.c:1176 tcp_write_queue_purge+0x143/0x2f0 net/ipv4/tcp.c:3288 tcp_done_with_error+0x43/0xd0 net/ipv4/tcp_input.c:4545 tcp_write_err net/ipv4/tcp_timer.c:77 [inline] tcp_write_timeout net/ipv4/tcp_timer.c:294 [inline] tcp_retransmit_timer+0x1456/0x3200 net/ipv4/tcp_timer.c:600 tcp_write_timer+0x162/0x2e0 net/ipv4/tcp_timer.c:738 call_timer_fn+0x17b/0x5f0 kernel/time/timer.c:1789 expire_timers kernel/time/timer.c:1840 [inline] __run_timers kernel/time/timer.c:2414 [inline] __run_timer_base+0x61a/0x860 kernel/time/timer.c:2426 run_timer_base kernel/time/timer.c:2435 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2445 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:raw_spin_rq_unlock_irq+0x13/0x90 kernel/sched/sched.h:1526 Code: cc e8 41 2c c3 09 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 57 41 56 53 66 90 e8 84 af c5 09 e8 ef 51 34 00 fb 5b <41> 5e 41 5f c3 cc cc cc cc cc f3 0f 1e fa 49 be 00 00 00 00 00 fc RSP: 0018:ffffc9000c406da8 EFLAGS: 00000286 RAX: 58399c5a2a4cfd00 RBX: ffff888024e6c380 RCX: 58399c5a2a4cfd00 RDX: 0000000000000007 RSI: ffffffff8d74afe2 RDI: ffffffff8bc1d520 RBP: ffffc9000c406fd0 R08: ffffffff8f7ed577 R09: 1ffffffff1efdaae R10: dffffc0000000000 R11: fffffbfff1efdaaf R12: ffff888024e6bc00 R13: dffffc0000000000 R14: ffff888024e6bc00 R15: ffff8880b8939b40 __schedule+0x1932/0x4cd0 kernel/sched/core.c:6771 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6947 preempt_schedule+0xae/0xc0 kernel/sched/core.c:6971 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0xfd/0x110 kernel/locking/spinlock.c:194 rcu_preempt_deferred_qs_irqrestore+0x851/0xc40 kernel/rcu/tree_plugin.h:-1 rcu_read_unlock_special+0x3fe/0x4c0 kernel/rcu/tree_plugin.h:693 __rcu_read_unlock+0x84/0xe0 kernel/rcu/tree_plugin.h:438 rcu_read_unlock include/linux/rcupdate.h:873 [inline] pte_unmap include/linux/pgtable.h:136 [inline] zap_pte_range mm/memory.c:1761 [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+0x37e8/0x4210 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: 0033:0x7ff1a2b8e969 Code: Unable to access opcode bytes at 0x7ff1a2b8e93f. RSP: 002b:00007ff1a39ca038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: 0000000000000004 RBX: 00007ff1a2db5fa0 RCX: 00007ff1a2b8e969 RDX: affffff7ffffffff RSI: 0000000000000000 RDI: 0000200000000180 RBP: 00007ff1a2c10ab1 R08: 0000000000000003 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ff1a2db5fa0 R15: 00007fff2f64fa58