====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Tainted: G L ------------------------------------------------------ syz-executor/25693 is trying to acquire lock: ffffffff8ea843c0 (fs_reclaim){+.+.}-{0:0}, at: might_alloc include/linux/sched/mm.h:317 [inline] ffffffff8ea843c0 (fs_reclaim){+.+.}-{0:0}, at: slab_pre_alloc_hook mm/slub.c:4520 [inline] ffffffff8ea843c0 (fs_reclaim){+.+.}-{0:0}, at: slab_alloc_node mm/slub.c:4875 [inline] ffffffff8ea843c0 (fs_reclaim){+.+.}-{0:0}, at: __kmalloc_cache_noprof+0x40/0x660 mm/slub.c:5407 but task is already holding lock: ffff88807d45c530 (&idev->mc_lock){+.+.}-{4:4}, at: __ipv6_dev_mc_inc+0x4e/0xa50 net/ipv6/mcast.c:943 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #7 (&idev->mc_lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:632 [inline] __mutex_lock+0x19e/0x1420 kernel/locking/mutex.c:794 __ipv6_dev_mc_inc+0x4e/0xa50 net/ipv6/mcast.c:943 __ipv6_sock_mc_join+0x51c/0x770 net/ipv6/mcast.c:234 do_ipv6_mcast_group_source+0x3df/0x4c0 net/ipv6/ipv6_sockglue.c:172 do_ipv6_setsockopt+0x16e9/0x3150 net/ipv6/ipv6_sockglue.c:911 ipv6_setsockopt+0x59/0x170 net/ipv6/ipv6_sockglue.c:965 do_sock_setsockopt+0x17c/0x1b0 net/socket.c:2395 __sys_setsockopt net/socket.c:2420 [inline] __do_sys_setsockopt net/socket.c:2426 [inline] __se_sys_setsockopt net/socket.c:2423 [inline] __x64_sys_setsockopt+0x13d/0x1b0 net/socket.c:2423 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 -> #6 (sk_lock-AF_INET6){+.+.}-{0:0}: lock_sock_nested+0x41/0x100 net/core/sock.c:3780 lock_sock include/net/sock.h:1713 [inline] inet_shutdown+0x6a/0x390 net/ipv4/af_inet.c:915 nbd_mark_nsock_dead+0x2e9/0x560 drivers/block/nbd.c:318 recv_work+0x1c2e/0x1d40 drivers/block/nbd.c:1021 process_one_work+0x9a3/0x1710 kernel/workqueue.c:3288 process_scheduled_works kernel/workqueue.c:3379 [inline] worker_thread+0xba8/0x11e0 kernel/workqueue.c:3465 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 -> #5 (&nsock->tx_lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:632 [inline] __mutex_lock+0x19e/0x1420 kernel/locking/mutex.c:794 nbd_handle_cmd drivers/block/nbd.c:1143 [inline] nbd_queue_rq+0x37b/0x1100 drivers/block/nbd.c:1207 blk_mq_dispatch_rq_list+0xa70/0x1910 block/blk-mq.c:2148 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:168 [inline] blk_mq_do_dispatch_sched block/blk-mq-sched.c:182 [inline] __blk_mq_sched_dispatch_requests+0xdcc/0x1600 block/blk-mq-sched.c:307 blk_mq_sched_dispatch_requests+0xd7/0x190 block/blk-mq-sched.c:329 blk_mq_run_hw_queue+0x348/0x4f0 block/blk-mq.c:2386 blk_mq_dispatch_list+0xd16/0xe10 include/linux/spinlock.h:-1 blk_mq_flush_plug_list+0x48d/0x570 block/blk-mq.c:2997 __blk_flush_plug+0x3ed/0x4d0 block/blk-core.c:1230 blk_finish_plug block/blk-core.c:1257 [inline] __submit_bio+0x28d/0x580 block/blk-core.c:649 __submit_bio_noacct_mq block/blk-core.c:722 [inline] submit_bio_noacct_nocheck+0x2f4/0xa40 block/blk-core.c:753 submit_bh fs/buffer.c:2842 [inline] block_read_full_folio+0x599/0x830 fs/buffer.c:2444 filemap_read_folio+0x137/0x3b0 mm/filemap.c:2502 do_read_cache_folio+0x358/0x590 mm/filemap.c:4107 read_mapping_folio include/linux/pagemap.h:1028 [inline] read_part_sector+0xb6/0x2b0 block/partitions/core.c:723 adfspart_check_ICS+0xa5/0xa40 block/partitions/acorn.c:360 check_partition block/partitions/core.c:142 [inline] blk_add_partitions block/partitions/core.c:590 [inline] bdev_disk_changed+0x7ba/0x1550 block/partitions/core.c:694 blkdev_get_whole+0x380/0x510 block/bdev.c:764 bdev_open+0x31e/0xd30 block/bdev.c:973 blkdev_open+0x470/0x610 block/fops.c:697 do_dentry_open+0x785/0x14e0 fs/open.c:949 vfs_open+0x3b/0x340 fs/open.c:1081 do_open fs/namei.c:4693 [inline] path_openat+0x2e08/0x3860 fs/namei.c:4852 do_file_open+0x23e/0x4a0 fs/namei.c:4881 do_sys_openat2+0x113/0x200 fs/open.c:1366 do_sys_open fs/open.c:1372 [inline] __do_sys_openat fs/open.c:1388 [inline] __se_sys_openat fs/open.c:1383 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1383 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 -> #4 (&cmd->lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:632 [inline] __mutex_lock+0x19e/0x1420 kernel/locking/mutex.c:794 nbd_queue_rq+0xc6/0x1100 drivers/block/nbd.c:1199 blk_mq_dispatch_rq_list+0xa70/0x1910 block/blk-mq.c:2148 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:168 [inline] blk_mq_do_dispatch_sched block/blk-mq-sched.c:182 [inline] __blk_mq_sched_dispatch_requests+0xdcc/0x1600 block/blk-mq-sched.c:307 blk_mq_sched_dispatch_requests+0xd7/0x190 block/blk-mq-sched.c:329 blk_mq_run_hw_queue+0x348/0x4f0 block/blk-mq.c:2386 blk_mq_dispatch_list+0xd16/0xe10 include/linux/spinlock.h:-1 blk_mq_flush_plug_list+0x48d/0x570 block/blk-mq.c:2997 __blk_flush_plug+0x3ed/0x4d0 block/blk-core.c:1230 blk_finish_plug block/blk-core.c:1257 [inline] __submit_bio+0x28d/0x580 block/blk-core.c:649 __submit_bio_noacct_mq block/blk-core.c:722 [inline] submit_bio_noacct_nocheck+0x2f4/0xa40 block/blk-core.c:753 submit_bh fs/buffer.c:2842 [inline] block_read_full_folio+0x599/0x830 fs/buffer.c:2444 filemap_read_folio+0x137/0x3b0 mm/filemap.c:2502 do_read_cache_folio+0x358/0x590 mm/filemap.c:4107 read_mapping_folio include/linux/pagemap.h:1028 [inline] read_part_sector+0xb6/0x2b0 block/partitions/core.c:723 adfspart_check_ICS+0xa5/0xa40 block/partitions/acorn.c:360 check_partition block/partitions/core.c:142 [inline] blk_add_partitions block/partitions/core.c:590 [inline] bdev_disk_changed+0x7ba/0x1550 block/partitions/core.c:694 blkdev_get_whole+0x380/0x510 block/bdev.c:764 bdev_open+0x31e/0xd30 block/bdev.c:973 blkdev_open+0x470/0x610 block/fops.c:697 do_dentry_open+0x785/0x14e0 fs/open.c:949 vfs_open+0x3b/0x340 fs/open.c:1081 do_open fs/namei.c:4693 [inline] path_openat+0x2e08/0x3860 fs/namei.c:4852 do_file_open+0x23e/0x4a0 fs/namei.c:4881 do_sys_openat2+0x113/0x200 fs/open.c:1366 do_sys_open fs/open.c:1372 [inline] __do_sys_openat fs/open.c:1388 [inline] __se_sys_openat fs/open.c:1383 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1383 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 -> #3 (set->srcu){.+.+}-{0:0}: srcu_lock_sync include/linux/srcu.h:199 [inline] __synchronize_srcu+0xca/0x3e0 kernel/rcu/srcutree.c:1505 elevator_switch+0x1e8/0x7a0 block/elevator.c:576 elevator_change+0x2cc/0x450 block/elevator.c:681 elevator_set_default+0x36c/0x430 block/elevator.c:754 blk_register_queue+0x3e9/0x4e0 block/blk-sysfs.c:987 __add_disk+0x677/0xd50 block/genhd.c:528 add_disk_fwnode+0xfb/0x480 block/genhd.c:597 add_disk include/linux/blkdev.h:793 [inline] nbd_dev_add+0x72c/0xb50 drivers/block/nbd.c:1984 nbd_init+0x168/0x1f0 drivers/block/nbd.c:2692 do_one_initcall+0x250/0x870 init/main.c:1386 do_initcall_level+0x104/0x190 init/main.c:1448 do_initcalls+0x59/0xa0 init/main.c:1464 kernel_init_freeable+0x2a6/0x3e0 init/main.c:1696 kernel_init+0x1d/0x1d0 init/main.c:1586 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 -> #2 (&q->elevator_lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:632 [inline] __mutex_lock+0x19e/0x1420 kernel/locking/mutex.c:794 elevator_change+0x1b3/0x450 block/elevator.c:679 elevator_set_none+0xb5/0x140 block/elevator.c:769 blk_mq_elv_switch_none block/blk-mq.c:5131 [inline] __blk_mq_update_nr_hw_queues block/blk-mq.c:5176 [inline] blk_mq_update_nr_hw_queues+0x5e7/0x1a60 block/blk-mq.c:5241 nbd_start_device+0x17f/0xb10 drivers/block/nbd.c:1489 nbd_genl_connect+0x165b/0x1cf0 drivers/block/nbd.c:2239 genl_family_rcv_msg_doit+0x22a/0x330 net/netlink/genetlink.c:1114 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline] genl_rcv_msg+0x61c/0x7a0 net/netlink/genetlink.c:1209 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x80f/0x9b0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec+0x112/0x150 net/socket.c:796 __sock_sendmsg net/socket.c:811 [inline] ____sys_sendmsg+0x589/0x8c0 net/socket.c:2668 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2722 __sys_sendmsg net/socket.c:2754 [inline] __do_sys_sendmsg net/socket.c:2759 [inline] __se_sys_sendmsg net/socket.c:2757 [inline] __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2757 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 -> #1 (&q->q_usage_counter(io)#49){++++}-{0:0}: blk_alloc_queue+0x546/0x680 block/blk-core.c:461 blk_mq_alloc_queue block/blk-mq.c:4450 [inline] __blk_mq_alloc_disk+0x197/0x390 block/blk-mq.c:4497 nbd_dev_add+0x499/0xb50 drivers/block/nbd.c:1954 nbd_init+0x168/0x1f0 drivers/block/nbd.c:2692 do_one_initcall+0x250/0x870 init/main.c:1386 do_initcall_level+0x104/0x190 init/main.c:1448 do_initcalls+0x59/0xa0 init/main.c:1464 kernel_init_freeable+0x2a6/0x3e0 init/main.c:1696 kernel_init+0x1d/0x1d0 init/main.c:1586 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 -> #0 (fs_reclaim){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __fs_reclaim_acquire mm/page_alloc.c:4312 [inline] fs_reclaim_acquire+0x71/0x100 mm/page_alloc.c:4326 might_alloc include/linux/sched/mm.h:317 [inline] slab_pre_alloc_hook mm/slub.c:4520 [inline] slab_alloc_node mm/slub.c:4875 [inline] __kmalloc_cache_noprof+0x40/0x660 mm/slub.c:5407 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] mca_alloc net/ipv6/mcast.c:871 [inline] __ipv6_dev_mc_inc+0x44f/0xa50 net/ipv6/mcast.c:961 ipv6_add_dev+0xe52/0x13c0 net/ipv6/addrconf.c:471 addrconf_notify+0x771/0x1050 net/ipv6/addrconf.c:3654 notifier_call_chain+0x1ad/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2289 [inline] call_netdevice_notifiers net/core/dev.c:2303 [inline] register_netdevice+0x173a/0x1cf0 net/core/dev.c:11481 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1066 [inline] nsim_create+0xb92/0x1100 drivers/net/netdevsim/netdev.c:1148 __nsim_dev_port_add+0x72a/0xb50 drivers/net/netdevsim/dev.c:1493 nsim_dev_port_add_all+0x37/0xf0 drivers/net/netdevsim/dev.c:1549 nsim_drv_probe+0x905/0xc20 drivers/net/netdevsim/dev.c:1710 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x267/0xaf0 drivers/base/dd.c:721 __driver_probe_device+0x18c/0x320 drivers/base/dd.c:863 driver_probe_device+0x4f/0x240 drivers/base/dd.c:893 __device_attach_driver+0x279/0x430 drivers/base/dd.c:1021 bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500 __device_attach+0x2c5/0x450 drivers/base/dd.c:1093 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1148 bus_probe_device+0x12a/0x220 drivers/base/bus.c:613 device_add+0x7b6/0xb70 drivers/base/core.c:3692 nsim_bus_dev_new drivers/net/netdevsim/bus.c:471 [inline] new_device_store+0x37b/0x710 drivers/net/netdevsim/bus.c:191 kernfs_fop_write_iter+0x3af/0x540 fs/kernfs/file.c:352 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x61d/0xb90 fs/read_write.c:688 ksys_write+0x150/0x270 fs/read_write.c:740 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 other info that might help us debug this: Chain exists of: fs_reclaim --> sk_lock-AF_INET6 --> &idev->mc_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&idev->mc_lock); lock(sk_lock-AF_INET6); lock(&idev->mc_lock); lock(fs_reclaim); *** DEADLOCK *** 9 locks held by syz-executor/25693: #0: ffff88803433a410 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2718 [inline] #0: ffff88803433a410 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x227/0xb90 fs/read_write.c:684 #1: ffff88805ce62080 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540 fs/kernfs/file.c:343 #2: ffff888026c1e1e8 (kn->active#53){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff888026c1e1e8 (kn->active#53){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540 fs/kernfs/file.c:344 #3: ffffffff8f667de0 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x13c/0x710 drivers/net/netdevsim/bus.c:184 #4: ffff888063336128 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:995 [inline] #4: ffff888063336128 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1068 #5: ffff888063330258 (&devlink->lock_key#19){+.+.}-{4:4}, at: nsim_drv_probe+0xc9/0xc20 drivers/net/netdevsim/dev.c:1637 #6: ffffffff8fdf6540 (rtnl_mutex){+.+.}-{4:4}, at: nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1054 [inline] #6: ffffffff8fdf6540 (rtnl_mutex){+.+.}-{4:4}, at: nsim_create+0x839/0x1100 drivers/net/netdevsim/netdev.c:1148 #7: ffff88807c6d0d98 (&dev_instance_lock_key#24){+.+.}-{4:4}, at: register_netdevice+0x1707/0x1cf0 net/core/dev.c:11480 #8: ffff88807d45c530 (&idev->mc_lock){+.+.}-{4:4}, at: __ipv6_dev_mc_inc+0x4e/0xa50 net/ipv6/mcast.c:943 stack backtrace: CPU: 0 UID: 0 PID: 25693 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_circular_bug+0x2e1/0x300 kernel/locking/lockdep.c:2043 check_noncircular+0x12e/0x150 kernel/locking/lockdep.c:2175 check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __fs_reclaim_acquire mm/page_alloc.c:4312 [inline] fs_reclaim_acquire+0x71/0x100 mm/page_alloc.c:4326 might_alloc include/linux/sched/mm.h:317 [inline] slab_pre_alloc_hook mm/slub.c:4520 [inline] slab_alloc_node mm/slub.c:4875 [inline] __kmalloc_cache_noprof+0x40/0x660 mm/slub.c:5407 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] mca_alloc net/ipv6/mcast.c:871 [inline] __ipv6_dev_mc_inc+0x44f/0xa50 net/ipv6/mcast.c:961 ipv6_add_dev+0xe52/0x13c0 net/ipv6/addrconf.c:471 addrconf_notify+0x771/0x1050 net/ipv6/addrconf.c:3654 notifier_call_chain+0x1ad/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2289 [inline] call_netdevice_notifiers net/core/dev.c:2303 [inline] register_netdevice+0x173a/0x1cf0 net/core/dev.c:11481 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1066 [inline] nsim_create+0xb92/0x1100 drivers/net/netdevsim/netdev.c:1148 __nsim_dev_port_add+0x72a/0xb50 drivers/net/netdevsim/dev.c:1493 nsim_dev_port_add_all+0x37/0xf0 drivers/net/netdevsim/dev.c:1549 nsim_drv_probe+0x905/0xc20 drivers/net/netdevsim/dev.c:1710 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x267/0xaf0 drivers/base/dd.c:721 __driver_probe_device+0x18c/0x320 drivers/base/dd.c:863 driver_probe_device+0x4f/0x240 drivers/base/dd.c:893 __device_attach_driver+0x279/0x430 drivers/base/dd.c:1021 bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500 __device_attach+0x2c5/0x450 drivers/base/dd.c:1093 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1148 bus_probe_device+0x12a/0x220 drivers/base/bus.c:613 device_add+0x7b6/0xb70 drivers/base/core.c:3692 nsim_bus_dev_new drivers/net/netdevsim/bus.c:471 [inline] new_device_store+0x37b/0x710 drivers/net/netdevsim/bus.c:191 kernfs_fop_write_iter+0x3af/0x540 fs/kernfs/file.c:352 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x61d/0xb90 fs/read_write.c:688 ksys_write+0x150/0x270 fs/read_write.c:740 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: 0033:0x7fbbb415cfce Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08 RSP: 002b:00007fff92848cc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000055555a68e500 RCX: 00007fbbb415cfce RDX: 0000000000000003 RSI: 00007fff92848d50 RDI: 0000000000000005 RBP: 00007fbbb4233540 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 00007fff92848d50 R14: 00007fbbb4f44620 R15: 0000000000000003 netdevsim netdevsim0 netdevsim0: renamed from eth0