watchdog: BUG: soft lockup - CPU#1 stuck for 120s! [syz.5.1491:12371] Modules linked in: irq event stamp: 13937335 hardirqs last enabled at (13937334): [] irqentry_exit+0x59e/0x620 kernel/entry/common.c:242 hardirqs last disabled at (13937335): [] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1056 softirqs last enabled at (13857354): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last enabled at (13857354): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last enabled at (13857354): [] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723 softirqs last disabled at (13857357): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last disabled at (13857357): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last disabled at (13857357): [] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723 CPU: 1 UID: 0 PID: 12371 Comm: syz.5.1491 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:lock_acquire+0x20b/0x2e0 kernel/locking/lockdep.c:5872 Code: e9 30 ff ff ff e8 65 95 0b 0a f7 c3 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 e1 22 7a 11 48 3b 44 24 30 75 33 fb 48 83 c4 38 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 c6 7b 0e 0a cc 48 8d 3d 9e 48 73 RSP: 0018:ffffc90000a08778 EFLAGS: 00000286 RAX: b0c356082693d300 RBX: 0000000000000246 RCX: 0000000000000102 RDX: 000000005a44979c RSI: ffffffff8e161e99 RDI: ffffffff8c27a480 RBP: 0000000000000000 R08: ffffffff81767a45 R09: ffffffff8e7602e0 R10: ffffc90000a083c8 R11: ffffffff81b0b130 R12: 0000000000000002 R13: ffffffff8e7602e0 R14: 0000000000000000 R15: 0000000000000000 FS: 00007fa2d46216c0(0000) GS:ffff888125566000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f650cd3c6c8 CR3: 000000007efe2000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000009 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] rcu_read_lock include/linux/rcupdate.h:850 [inline] class_rcu_constructor include/linux/rcupdate.h:1193 [inline] unwind_next_frame+0xc2/0x23c0 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 __call_rcu_common kernel/rcu/tree.c:3131 [inline] call_rcu+0xee/0x890 kernel/rcu/tree.c:3251 slab_free_hook mm/slub.c:2651 [inline] slab_free mm/slub.c:6124 [inline] kmem_cache_free+0x439/0x630 mm/slub.c:6254 mempool_free+0xec/0x130 mm/mempool.c:712 blk_update_request+0x57e/0xe60 block/blk-mq.c:1016 scsi_end_request+0x7c/0x820 drivers/scsi/scsi_lib.c:647 scsi_io_completion+0x131/0x360 drivers/scsi/scsi_lib.c:1088 blk_complete_reqs block/blk-mq.c:1253 [inline] blk_done_softirq+0x10a/0x160 block/blk-mq.c:1258 handle_softirqs+0x22a/0x870 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:perf_swevent_event+0x56/0x650 kernel/events/core.c:10852 Code: 8b 05 de bd 22 11 48 89 84 24 80 00 00 00 49 bd 00 00 00 00 00 fc ff df 48 c7 44 24 40 b3 8a b5 41 48 c7 44 24 48 35 f3 00 8e <48> c7 44 24 50 10 e2 f8 81 48 8d 5c 24 40 48 c1 eb 03 48 b8 f1 f1 RSP: 0018:ffffc900041a6320 EFLAGS: 00000282 RAX: b0c356082693d300 RBX: ffff888035f38000 RCX: ffff8880b8733350 RDX: ffffc900041a64c0 RSI: 0000000000000001 RDI: ffff888035f38000 RBP: ffffc900041a63f0 R08: ffffc900041a64d7 R09: 0000000000000000 R10: ffffc900041a64c8 R11: fffff52000834c9b R12: 0000000000000001 R13: dffffc0000000000 R14: ffff8880b8733350 R15: ffff888035f38000 perf_tp_event+0x571/0x29b0 kernel/events/core.c:11382 perf_trace_run_bpf_submit+0xee/0x170 kernel/events/core.c:11306 do_perf_trace_lock include/trace/events/lock.h:50 [inline] perf_trace_lock+0x32d/0x410 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+0x392/0x3d0 kernel/locking/lockdep.c:5879 rcu_lock_release include/linux/rcupdate.h:322 [inline] rcu_read_unlock include/linux/rcupdate.h:881 [inline] class_rcu_destructor include/linux/rcupdate.h:1193 [inline] unwind_next_frame+0x1aaa/0x23c0 arch/x86/kernel/unwind_orc.c:695 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 __call_rcu_common kernel/rcu/tree.c:3131 [inline] call_rcu+0xee/0x890 kernel/rcu/tree.c:3251 context_switch kernel/sched/core.c:5298 [inline] __schedule+0x158d/0x5340 kernel/sched/core.c:6907 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7234 irqentry_exit+0x599/0x620 kernel/entry/common.c:239 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:unwind_get_return_address+0x45/0x90 arch/x86/kernel/unwind_orc.c:385 Code: e8 03 42 0f b6 04 30 84 c0 75 4c 83 3b 00 74 3a 48 83 c3 48 49 89 df 49 c1 ef 03 43 80 3c 37 00 74 08 48 89 df e8 5b 37 b9 00 <48> 8b 3b e8 53 6c 19 00 85 c0 74 14 43 80 3c 37 00 74 08 48 89 df RSP: 0018:ffffc900041a70c8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffc900041a7130 RCX: 0000000000000046 RDX: 0000000000000002 RSI: ffffffff8e161e99 RDI: ffffc900041a70e8 RBP: ffffc900041a7170 R08: ffffc900041a6c57 R09: 0000000000000000 R10: ffffc900041a6c48 R11: fffff52000834d8b R12: ffff88801fb33c80 R13: 1ffff11003f66846 R14: dffffc0000000000 R15: 1ffff92000834e26 arch_stack_walk+0xfb/0x150 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 save_stack+0x122/0x230 mm/page_owner.c:165 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:320 reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1433 [inline] __free_frozen_pages+0xc2b/0xdb0 mm/page_alloc.c:2978 __slab_free+0x263/0x2b0 mm/slub.c:5532 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4501 [inline] slab_alloc_node mm/slub.c:4830 [inline] __kmalloc_cache_noprof+0x2ba/0x660 mm/slub.c:5334 kmalloc_noprof include/linux/slab.h:962 [inline] kzalloc_noprof include/linux/slab.h:1204 [inline] genradix_alloc_node include/linux/generic-radix-tree.h:101 [inline] __genradix_ptr_alloc+0x352/0x4a0 lib/generic-radix-tree.c:69 __genradix_prealloc+0x44/0x90 lib/generic-radix-tree.c:216 sctp_stream_alloc_out net/sctp/stream.c:104 [inline] sctp_stream_init+0x5f0/0x940 net/sctp/stream.c:149 sctp_connect_new_asoc+0x3c0/0x6b0 net/sctp/socket.c:1114 sctp_sendmsg_new_asoc net/sctp/socket.c:1692 [inline] sctp_sendmsg+0x1528/0x2c10 net/sctp/socket.c:2003 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] ____sys_sendmsg+0x894/0xad0 net/socket.c:2592 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2646 __sys_sendmsg net/socket.c:2678 [inline] __do_sys_sendmsg net/socket.c:2683 [inline] __se_sys_sendmsg net/socket.c:2681 [inline] __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2681 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa2d379c629 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:00007fa2d4621028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fa2d3a16090 RCX: 00007fa2d379c629 RDX: 000000002c0408d0 RSI: 0000200000000400 RDI: 000000000000000a RBP: 00007fa2d3832b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa2d3a16128 R14: 00007fa2d3a16090 R15: 00007ffd3dcd3858 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 12376 Comm: syz.7.1494 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline] RIP: 0010:smp_call_function_many_cond+0xcea/0x12c0 kernel/smp.c:877 Code: 89 ee 83 e6 01 31 ff e8 24 e3 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 cf de 0b 00 eb 38 f3 90 42 0f b6 04 2b <84> c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 b3 de 0b 00 eb e4 44 RSP: 0018:ffffc90004217440 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 1ffff110170e812d RCX: ffff88802c7b1e40 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90004217580 R08: ffffffff901172b7 R09: 1ffffffff2022e56 R10: dffffc0000000000 R11: fffffbfff2022e57 R12: ffff8880b8740968 R13: dffffc0000000000 R14: ffff8880b863bf80 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff888125466000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055556de0f4e8 CR3: 000000000e54c000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043 __flush_tlb_multi arch/x86/include/asm/paravirt.h:57 [inline] flush_tlb_multi arch/x86/mm/tlb.c:1382 [inline] flush_tlb_mm_range+0x5c3/0x10c0 arch/x86/mm/tlb.c:1472 tlb_flush arch/x86/include/asm/tlb.h:23 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:505 [inline] tlb_flush_mmu+0x1af/0xa30 mm/mmu_gather.c:404 tlb_finish_mmu+0xf9/0x230 mm/mmu_gather.c:530 free_ldt_pgtables+0x19d/0x350 arch/x86/kernel/ldt.c:411 arch_exit_mmap arch/x86/include/asm/mmu_context.h:232 [inline] exit_mmap+0x1af/0xa10 mm/mmap.c:1287 __mmput+0x118/0x430 kernel/fork.c:1174 exit_mm+0x168/0x220 kernel/exit.c:581 do_exit+0x62e/0x2320 kernel/exit.c:959 do_group_exit+0x21b/0x2d0 kernel/exit.c:1112 get_signal+0x1284/0x1330 kernel/signal.c:3034 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f97d199c629 Code: Unable to access opcode bytes at 0x7f97d199c5ff. RSP: 002b:00007f97d2839028 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: 000000000000000f RBX: 00007f97d1c15fa0 RCX: 00007f97d199c629 RDX: 000000000000000c RSI: 0000000000000003 RDI: 0000000000000010 RBP: 00007f97d1a32b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f97d1c16038 R14: 00007f97d1c15fa0 R15: 00007ffe36504108