Extracting prog: 8m7.334468979s Minimizing prog: 31m7.117590835s Simplifying prog options: 10m10.767117945s Extracting C: 5m14.407493025s Simplifying C: 0s extracting reproducer from 1 programs testing a last program of every proc single: executing 1 programs separately with timeout 30s testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:6 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$uhid-write$UHID_CREATE2 detailed listing: executing program 0: r0 = openat$uhid(0xffffffffffffff9c, &(0x7f0000000000), 0x2, 0x0) write$UHID_CREATE2(r0, &(0x7f0000002700)=ANY=[@ANYBLOB="0b00000073797a300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000073797a3000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000073797a300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000010"], 0x1118) program did not crash single: failed to extract reproducer single: executing 1 programs separately with timeout 1m40s testing program (duration=1m40s, {Threaded:true Repeat:true RepeatTimes:0 Procs:6 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$uhid-write$UHID_CREATE2 detailed listing: executing program 0: r0 = openat$uhid(0xffffffffffffff9c, &(0x7f0000000000), 0x2, 0x0) write$UHID_CREATE2(r0, &(0x7f0000002700)=ANY=[@ANYBLOB="0b00000073797a300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000073797a3000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000073797a300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000010"], 0x1118) program did not crash single: failed to extract reproducer single: executing 1 programs separately with timeout 6m0s testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:6 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$uhid-write$UHID_CREATE2 detailed listing: executing program 0: r0 = openat$uhid(0xffffffffffffff9c, &(0x7f0000000000), 0x2, 0x0) write$UHID_CREATE2(r0, &(0x7f0000002700)=ANY=[@ANYBLOB="0b00000073797a300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000073797a3000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000073797a300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000010"], 0x1118) program crashed: INFO: task hung in uhid_char_release single: successfully extracted reproducer found reproducer with 2 syscalls minimizing guilty program testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:6 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$uhid detailed listing: executing program 0: openat$uhid(0xffffffffffffff9c, &(0x7f0000000000), 0x2, 0x0) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:6 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): write$UHID_CREATE2 detailed listing: executing program 0: write$UHID_CREATE2(0xffffffffffffffff, &(0x7f0000002700)=ANY=[@ANYBLOB="0b00000073797a300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000073797a3000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000073797a300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000010"], 0x1118) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:6 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$uhid-write$UHID_CREATE2 detailed listing: executing program 0: r0 = openat$uhid(0xffffffffffffff9c, 0x0, 0x2, 0x0) write$UHID_CREATE2(r0, &(0x7f0000002700)=ANY=[@ANYBLOB="0b00000073797a300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000073797a3000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000073797a300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000010"], 0x1118) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:6 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$uhid-write$UHID_CREATE2 detailed listing: executing program 0: r0 = openat$uhid(0xffffffffffffff9c, &(0x7f0000000000), 0x2, 0x0) write$UHID_CREATE2(r0, 0x0, 0x1118) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:6 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$uhid-write$UHID_CREATE2 detailed listing: executing program 0: r0 = openat$uhid(0xffffffffffffff9c, &(0x7f0000000000), 0x2, 0x0) write$UHID_CREATE2(r0, &(0x7f0000002700)=ANY=[@ANYBLOB], 0x1118) program did not crash extracting C reproducer testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:6 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$uhid-write$UHID_CREATE2 program crashed: no output from test machine a never seen crash title: no output from test machine, ignore simplifying guilty program options testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:6 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$uhid-write$UHID_CREATE2 detailed listing: executing program 0: r0 = openat$uhid(0xffffffffffffff9c, &(0x7f0000000000), 0x2, 0x0) write$UHID_CREATE2(r0, &(0x7f0000002700)=ANY=[@ANYBLOB="0b00000073797a300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000073797a3000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000073797a300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000010"], 0x1118) program crashed: INFO: task hung in uevent_show a never seen crash title: INFO: task hung in uevent_show, ignore testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$uhid-write$UHID_CREATE2 detailed listing: executing program 0: r0 = openat$uhid(0xffffffffffffff9c, &(0x7f0000000000), 0x2, 0x0) write$UHID_CREATE2(r0, &(0x7f0000002700)=ANY=[@ANYBLOB="0b00000073797a300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000073797a3000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000073797a300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000010"], 0x1118) program did not crash reproducing took 54m39.62668362s repro crashed as (corrupted=false): ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00000000000165bf RCX: 00007f03cb785d29 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f03cb977ba0 R08: 0000000000000001 R09: 00007ffff7fa51ef R10: 00007f03cb600000 R11: 0000000000000246 R12: 000000000001660c R13: 00007f03cb975fa0 R14: 0000000000000032 R15: ffffffffffffffff INFO: task syz.2.18:6114 blocked for more than 152 seconds. Not tainted 6.13.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.18 state:D stack:25952 pid:6114 tgid:6114 ppid:5930 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0xb0/0x290 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion+0x355/0x620 kernel/sched/completion.c:148 __flush_work+0xa47/0xc60 kernel/workqueue.c:4242 __cancel_work_sync+0xbc/0x110 kernel/workqueue.c:4362 uhid_dev_destroy drivers/hid/uhid.c:584 [inline] uhid_char_release+0xac/0x600 drivers/hid/uhid.c:662 __fput+0x23e/0xa50 fs/file_table.c:450 task_work_run+0x251/0x310 kernel/task_work.c:239 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [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+0x13f/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7d3b785d29 RSP: 002b:00007fff447e1578 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 0000000000016bbd RCX: 00007f7d3b785d29 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f7d3b977ba0 R08: 0000000000000001 R09: 00007fff447e186f R10: 00007f7d3b600000 R11: 0000000000000246 R12: 0000000000016bfa R13: 00007f7d3b975fa0 R14: 0000000000000032 R15: ffffffffffffffff Showing all locks held in the system: 3 locks held by kworker/0:0/8: 3 locks held by kworker/u8:1/12: #0: ffff88801ac81148 ((wq_completion)events_unbound ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3211 [inline] , at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3317 #1: ffffc90000117d00 ( (linkwatch_work).work ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3212 [inline] , at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3317 #2: ffffffff8fcb5608 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:285 3 locks held by kworker/1:0/25: 1 lock held by khungtaskd/30: #0: ffffffff8e937ae0 ( rcu_read_lock ){....}-{1:3} , at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] , at: rcu_read_lock include/linux/rcupdate.h:849 [inline] , at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744 3 locks held by kworker/u8:2/35: #0: ffff88814d001148 ( (wq_completion)ipv6_addrconf ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3211 [inline] , at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3317 #1: ffffc90000ab7d00 ( (work_completion)(&(&ifa->dad_work)->work) ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3212 [inline] , at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3317 #2: ffffffff8fcb5608 ( rtnl_mutex){+.+.}-{4:4} , at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4215 2 locks held by kworker/u8:5/1090: 5 locks held by kworker/u8:6/1331: #0: ffff88801baed948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801baed948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3317 #1: ffffc9000427fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000427fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3317 #2: ffffffff8fca9150 (pernet_ops_rwsem ){++++}-{4:4} , at: cleanup_net+0x16a/0xd50 net/core/net_namespace.c:602 #3: ffffffff8fcb5608 ( rtnl_mutex ){+.+.}-{4:4} , at: default_device_exit_batch+0xe9/0xaa0 net/core/dev.c:12078 final repro crashed as (corrupted=false): ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00000000000165bf RCX: 00007f03cb785d29 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f03cb977ba0 R08: 0000000000000001 R09: 00007ffff7fa51ef R10: 00007f03cb600000 R11: 0000000000000246 R12: 000000000001660c R13: 00007f03cb975fa0 R14: 0000000000000032 R15: ffffffffffffffff INFO: task syz.2.18:6114 blocked for more than 152 seconds. Not tainted 6.13.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.18 state:D stack:25952 pid:6114 tgid:6114 ppid:5930 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0xb0/0x290 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion+0x355/0x620 kernel/sched/completion.c:148 __flush_work+0xa47/0xc60 kernel/workqueue.c:4242 __cancel_work_sync+0xbc/0x110 kernel/workqueue.c:4362 uhid_dev_destroy drivers/hid/uhid.c:584 [inline] uhid_char_release+0xac/0x600 drivers/hid/uhid.c:662 __fput+0x23e/0xa50 fs/file_table.c:450 task_work_run+0x251/0x310 kernel/task_work.c:239 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [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+0x13f/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7d3b785d29 RSP: 002b:00007fff447e1578 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 0000000000016bbd RCX: 00007f7d3b785d29 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f7d3b977ba0 R08: 0000000000000001 R09: 00007fff447e186f R10: 00007f7d3b600000 R11: 0000000000000246 R12: 0000000000016bfa R13: 00007f7d3b975fa0 R14: 0000000000000032 R15: ffffffffffffffff Showing all locks held in the system: 3 locks held by kworker/0:0/8: 3 locks held by kworker/u8:1/12: #0: ffff88801ac81148 ((wq_completion)events_unbound ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3211 [inline] , at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3317 #1: ffffc90000117d00 ( (linkwatch_work).work ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3212 [inline] , at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3317 #2: ffffffff8fcb5608 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:285 3 locks held by kworker/1:0/25: 1 lock held by khungtaskd/30: #0: ffffffff8e937ae0 ( rcu_read_lock ){....}-{1:3} , at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] , at: rcu_read_lock include/linux/rcupdate.h:849 [inline] , at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744 3 locks held by kworker/u8:2/35: #0: ffff88814d001148 ( (wq_completion)ipv6_addrconf ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3211 [inline] , at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3317 #1: ffffc90000ab7d00 ( (work_completion)(&(&ifa->dad_work)->work) ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3212 [inline] , at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3317 #2: ffffffff8fcb5608 ( rtnl_mutex){+.+.}-{4:4} , at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4215 2 locks held by kworker/u8:5/1090: 5 locks held by kworker/u8:6/1331: #0: ffff88801baed948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801baed948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3317 #1: ffffc9000427fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000427fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3317 #2: ffffffff8fca9150 (pernet_ops_rwsem ){++++}-{4:4} , at: cleanup_net+0x16a/0xd50 net/core/net_namespace.c:602 #3: ffffffff8fcb5608 ( rtnl_mutex ){+.+.}-{4:4} , at: default_device_exit_batch+0xe9/0xaa0 net/core/dev.c:12078