====================================== | [ 2903.833752][T20194] 1 lock held by arping/20194: | [2903.833928][T20194] #0: ffffffff8736f640 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit (./include/linux/bottom_half.h:20 ./include/linux/rcupdate.h:901 net/core/dev.c:4555) | [ 2903.834248][T20194] | [ 2903.834248][T20194] stack backtrace: [ 2903.834452][T20194] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 2903.834458][T20194] Call Trace: [ 2903.834464][T20194] [2903.834467][T20194] dump_stack_lvl (lib/dump_stack.c:123) [2903.834478][T20194] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6848) [2903.834500][T20194] dev_hard_start_xmit (./include/net/net_namespace.h:418 ./include/linux/netdevice.h:2695 net/core/dev.c:2466 net/core/dev.c:3772 net/core/dev.c:3793) [2903.834512][T20194] __dev_queue_xmit (net/core/dev.h:340 net/core/dev.c:4631) [2903.834516][T20194] ? _copy_from_iter (./arch/x86/include/asm/uaccess_64.h:126 ./arch/x86/include/asm/uaccess_64.h:141 lib/iov_iter.c:55 ./include/linux/iov_iter.h:30 ./include/linux/iov_iter.h:300 ./include/linux/iov_iter.h:328 lib/iov_iter.c:249 lib/iov_iter.c:260) [2903.834534][T20194] ? __pfx___dev_queue_xmit (net/core/dev.c:4538) [2903.834540][T20194] ? packet_parse_headers (./include/linux/skbuff.h:3108 net/packet/af_packet.c:1992) [2903.834551][T20194] ? __pfx_sock_alloc_send_pskb (net/core/sock.c:2922) [2903.834562][T20194] ? __pfx_packet_parse_headers (net/packet/af_packet.c:1977) [2903.834567][T20194] ? skb_copy_datagram_from_iter (net/core/datagram.c:564) [2903.834576][T20194] ? dev_get_by_index (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/dev.c:982) [2903.834587][T20194] packet_snd (net/packet/af_packet.c:3131) [2903.834600][T20194] ? __lock_release (kernel/locking/lockdep.c:5527) [2903.834603][T20194] ? __might_fault (mm/memory.c:6858 mm/memory.c:6851) [2903.834616][T20194] ? __pfx_packet_snd (net/packet/af_packet.c:2995) [2903.834619][T20194] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 21)) [2903.834622][T20194] ? __pfx___lock_release (kernel/locking/lockdep.c:5503) [2903.834629][T20194] ? lock_acquire (kernel/locking/lockdep.c:5824) [2903.834635][T20194] ? __might_fault (mm/memory.c:6858 mm/memory.c:6851) [2903.834646][T20194] __sys_sendto (net/socket.c:709 net/socket.c:724 net/socket.c:2177) [2903.834655][T20194] ? __pfx___sys_sendto (net/socket.c:2144) [2903.834667][T20194] ? __lock_release (kernel/locking/lockdep.c:5527) [2903.834672][T20194] ? __pfx___lock_release (kernel/locking/lockdep.c:5503) [2903.834680][T20194] ? __pfx___up_read (kernel/locking/rwsem.c:1337) [2903.834687][T20194] ? do_user_addr_fault (./include/linux/mmap_lock.h:218 arch/x86/mm/fault.c:1416) [2903.834704][T20194] ? do_user_addr_fault (./include/linux/mmap_lock.h:218 arch/x86/mm/fault.c:1416) [2903.834711][T20194] __x64_sys_sendto (net/socket.c:2180) [2903.834716][T20194] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4349 kernel/locking/lockdep.c:4408) [2903.834721][T20194] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) [2903.834732][T20194] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) [ 2903.834743][T20194] RIP: 0033:0x7f9bac753a4a [ 2903.834748][T20194] Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 f3 0f 1e fa 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 15 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 7e c3 0f 1f 44 00 00 41 54 48 83 ec 30 44 89 All code ======== 0: d8 64 89 02 fsubs 0x2(%rcx,%rcx,4) 4: 48 c7 c0 ff ff ff ff mov $0xffffffffffffffff,%rax b: eb b8 jmp 0xffffffffffffffc5 d: 0f 1f 00 nopl (%rax) 10: f3 0f 1e fa endbr64 14: 41 89 ca mov %ecx,%r10d 17: 64 8b 04 25 18 00 00 mov %fs:0x18,%eax 1e: 00 1f: 85 c0 test %eax,%eax 21: 75 15 jne 0x38 23: b8 2c 00 00 00 mov $0x2c,%eax 28: 0f 05 syscall 2a:* 48 3d 00 f0 ff ff cmp $0xfffffffffffff000,%rax <-- trapping instruction 30: 77 7e ja 0xb0 32: c3 ret 33: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 38: 41 54 push %r12 3a: 48 83 ec 30 sub $0x30,%rsp 3e: 44 rex.R 3f: 89 .byte 0x89 Code starting with the faulting instruction =========================================== 0: 48 3d 00 f0 ff ff cmp $0xfffffffffffff000,%rax 6: 77 7e ja 0x86 8: c3 ret 9: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) e: 41 54 push %r12 10: 48 83 ec 30 sub $0x30,%rsp 14: 44 rex.R 15: 89 .byte 0x89 [ 2903.834751][T20194] RSP: 002b:00007fff4d491b28 EFLAGS: 00000246 ORIG_RAX: 000000000000002c [ 2903.834756][T20194] RAX: ffffffffffffffda RBX: 0000000000000100 RCX: 00007f9bac753a4a [ 2903.834759][T20194] RDX: 000000000000001c RSI: 00007fff4d491b40 RDI: 0000000000000005 [ 2903.834761][T20194] RBP: 00007fff4d491c90 R08: 00007fff4d4930f0 R09: 0000000000000014 [ 2903.834762][T20194] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f9bac601710 Finger prints: lockdep_rcu_suspicious:dev_hard_start_xmit:__dev_queue_xmit:packet_snd:__sys_sendto