watchdog: BUG: soft lockup - CPU#0 stuck for 23s! [syz-executor.2:5799] Modules linked in: irq event stamp: 5177033 hardirqs last enabled at (5177032): [] slab_alloc_node mm/slab.c:3334 [inline] hardirqs last enabled at (5177032): [] kmem_cache_alloc_node+0x2da/0x3b0 mm/slab.c:3647 hardirqs last disabled at (5177033): [] trace_hardirqs_off_thunk+0x1a/0x1c softirqs last enabled at (0): [] copy_process.part.0+0x15b9/0x8260 kernel/fork.c:1856 softirqs last disabled at (115): [] invoke_softirq kernel/softirq.c:372 [inline] softirqs last disabled at (115): [] irq_exit+0x215/0x260 kernel/softirq.c:412 CPU: 0 PID: 5799 Comm: syz-executor.2 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:334 [inline] RIP: 0010:deref_stack_reg+0x13d/0x1d0 arch/x86/kernel/unwind_orc.c:328 Code: 89 ef e8 16 33 f7 ff 41 89 c0 31 c0 45 85 c0 75 32 48 8d 74 24 28 48 89 ef 4c 89 ea e8 cc fc ff ff 48 c1 ea 03 48 8b 6c 24 28 <48> b8 00 00 00 00 00 fc ff df 80 3c 02 00 75 4c 49 89 6d 00 b8 01 RSP: 0018:ffff8880ba0076f0 EFLAGS: 00000a02 ORIG_RAX: ffffffffffffff13 RAX: ffffffff867098b1 RBX: 1ffff11017400edf RCX: 0000000000000000 RDX: 1ffff11017400f20 RSI: ffff8880ba007718 RDI: ffff8880ba007be0 RBP: ffffffff867098b1 R08: ffffffff8b99ceae R09: ffffffff8b99ceaa R10: ffff8880ba007917 R11: 0000000000074071 R12: ffff8880ba0078b8 R13: ffff8880ba007900 R14: ffff8880ba000000 R15: ffffffff8b99ceaa FS: 00007faf57848700(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5c9fd76718 CR3: 0000000237ddc000 CR4: 00000000003406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_next_frame+0x9fc/0x1400 arch/x86/kernel/unwind_orc.c:502 __save_stack_trace+0x9f/0x190 arch/x86/kernel/stacktrace.c:44 save_stack mm/kasan/kasan.c:448 [inline] set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:553 slab_post_alloc_hook mm/slab.h:445 [inline] slab_alloc_node mm/slab.c:3340 [inline] kmem_cache_alloc_node+0x133/0x3b0 mm/slab.c:3647 __alloc_skb+0x71/0x560 net/core/skbuff.c:193 alloc_skb include/linux/skbuff.h:995 [inline] mrp_pdu_init net/802/mrp.c:316 [inline] mrp_pdu_append_vecattr_event+0x7d2/0x1050 net/802/mrp.c:415 mrp_attr_event+0x15d/0x220 net/802/mrp.c:510 mrp_mad_event net/802/mrp.c:590 [inline] mrp_join_timer+0x5a/0xc0 net/802/mrp.c:607 call_timer_fn+0x177/0x700 kernel/time/timer.c:1338 expire_timers+0x243/0x4e0 kernel/time/timer.c:1375 __run_timers kernel/time/timer.c:1696 [inline] run_timer_softirq+0x21c/0x670 kernel/time/timer.c:1709 __do_softirq+0x265/0x980 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:372 [inline] irq_exit+0x215/0x260 kernel/softirq.c:412 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1098 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:789 [inline] RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa3/0xe0 kernel/locking/spinlock.c:184 Code: 48 c7 c0 88 82 f1 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 2f 48 83 3d 7c 31 d8 01 00 74 15 48 89 df 57 9d <0f> 1f 44 00 00 eb b2 e8 fb eb e6 f8 eb c0 0f 0b 0f 0b 48 c7 c7 88 RSP: 0018:ffff88823a827a30 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff13e3051 RBX: 0000000000000286 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: 0000000000000001 RDI: 0000000000000286 RBP: ffff8880a132fdc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880a263c350 R13: 00000000000002b0 R14: 0000000000000286 R15: 0000000000000001 spin_unlock_irqrestore include/linux/spinlock.h:384 [inline] fill_tgid_exit kernel/taskstats.c:284 [inline] taskstats_exit+0x28d/0xc10 kernel/taskstats.c:619 do_exit+0x677/0x2be0 kernel/exit.c:855 do_group_exit+0x125/0x310 kernel/exit.c:967 get_signal+0x3f2/0x1f70 kernel/signal.c:2589 do_signal+0x8f/0x1670 arch/x86/kernel/signal.c:799 exit_to_usermode_loop+0x204/0x2a0 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7faf58ef40e9 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007faf57848218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007faf59007038 RCX: 00007faf58ef40e9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007faf59007038 RBP: 00007faf59007030 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007faf5900703c R13: 00007ffd02f0a0ef R14: 00007faf57848300 R15: 0000000000022000 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 2889 Comm: kworker/u4:4 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:__lock_acquire+0x895/0x3ff0 kernel/locking/lockdep.c:3413 Code: c2 c1 c1 10 89 d6 41 31 c8 44 89 c1 44 29 c0 41 01 d0 c1 c9 0d 31 c8 89 c1 29 c6 44 01 c0 c1 c1 04 31 f1 48 c1 e1 20 48 09 c1 <48> 85 ff 49 89 cc 74 1a be ff ff ff ff 4c 89 14 24 e8 e5 b2 ff ff RSP: 0018:ffff8880ac37fa68 EFLAGS: 00000002 RAX: 00000000d4f3aef2 RBX: 44e964d3e27bd066 RCX: 163bbd11d4f3aef2 RDX: 00000000ffad4755 RSI: 0000000049b447aa RDI: 0000000000000000 RBP: 0000000000000000 R08: 000000001efaaf47 R09: 0000000000000002 R10: ffff8880ac370918 R11: 0000000000000000 R12: 000000000002002e R13: ffff8880ac370040 R14: ffff8880ac370930 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005555565a0848 CR3: 00000000ab7e1000 CR4: 00000000003406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3908 rcu_lock_acquire include/linux/rcupdate.h:242 [inline] rcu_read_lock include/linux/rcupdate.h:627 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:419 [inline] batadv_nc_worker+0x12d/0xd50 net/batman-adv/network-coding.c:730 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 ---------------- Code disassembly (best guess): 0: 89 ef mov %ebp,%edi 2: e8 16 33 f7 ff callq 0xfff7331d 7: 41 89 c0 mov %eax,%r8d a: 31 c0 xor %eax,%eax c: 45 85 c0 test %r8d,%r8d f: 75 32 jne 0x43 11: 48 8d 74 24 28 lea 0x28(%rsp),%rsi 16: 48 89 ef mov %rbp,%rdi 19: 4c 89 ea mov %r13,%rdx 1c: e8 cc fc ff ff callq 0xfffffced 21: 48 c1 ea 03 shr $0x3,%rdx 25: 48 8b 6c 24 28 mov 0x28(%rsp),%rbp * 2a: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax <-- trapping instruction 31: fc ff df 34: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) 38: 75 4c jne 0x86 3a: 49 89 6d 00 mov %rbp,0x0(%r13) 3e: b8 .byte 0xb8 3f: 01 .byte 0x1