syzbot

INFO: task syz.2.19:6079 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.19        state:D stack:26984 pid:6079  tgid:6079  ppid:5947   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x16f3/0x4c20 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7307
 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
 __rt_mutex_slowlock_locked+0x1e04/0x25e0 kernel/locking/rtmutex.c:1760
 rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800
 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
 rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244
 inode_lock include/linux/fs.h:980 [inline]
 blkdev_fallocate+0x263/0x550 block/fops.c:911
 vfs_fallocate+0x672/0x7f0 fs/open.c:342
 ksys_fallocate fs/open.c:366 [inline]
 __do_sys_fallocate fs/open.c:371 [inline]
 __se_sys_fallocate fs/open.c:369 [inline]
 __x64_sys_fallocate+0xc0/0x110 fs/open.c:369
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3b4192f749
RSP: 002b:00007ffea66d8838 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 00007f3b41b85fa0 RCX: 00007f3b4192f749
RDX: 0000000000002000 RSI: 0000000000000010 RDI: 0000000000000003
RBP: 00007f3b419b3f91 R08: 0000000000000000 R09: 0000000000000000
R10: 000000100007c000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3b41b85fa0 R14: 00007f3b41b85fa0 R15: 0000000000000004
 </TASK>
INFO: task syz.3.20:6081 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.20        state:D stack:26424 pid:6081  tgid:6081  ppid:5948   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x16f3/0x4c20 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7307
 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
 __rt_mutex_slowlock_locked+0x1e04/0x25e0 kernel/locking/rtmutex.c:1760
 rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800
 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
 rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244
 inode_lock include/linux/fs.h:980 [inline]
 blkdev_fallocate+0x263/0x550 block/fops.c:911
 vfs_fallocate+0x672/0x7f0 fs/open.c:342
 ksys_fallocate fs/open.c:366 [inline]
 __do_sys_fallocate fs/open.c:371 [inline]
 __se_sys_fallocate fs/open.c:369 [inline]
 __x64_sys_fallocate+0xc0/0x110 fs/open.c:369
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f686cbff749
RSP: 002b:00007fff39d3bda8 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 00007f686ce55fa0 RCX: 00007f686cbff749
RDX: 0000000000002000 RSI: 0000000000000010 RDI: 0000000000000003
RBP: 00007f686cc83f91 R08: 0000000000000000 R09: 0000000000000000
R10: 000000100007c000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f686ce55fa0 R14: 00007f686ce55fa0 R15: 0000000000000004
 </TASK>
INFO: task syz.4.21:6082 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.21        state:D stack:26984 pid:6082  tgid:6082  ppid:5949   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x16f3/0x4c20 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7307
 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
 __rt_mutex_slowlock_locked+0x1e04/0x25e0 kernel/locking/rtmutex.c:1760
 rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800
 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
 rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244
 inode_lock include/linux/fs.h:980 [inline]
 blkdev_fallocate+0x263/0x550 block/fops.c:911
 vfs_fallocate+0x672/0x7f0 fs/open.c:342
 ksys_fallocate fs/open.c:366 [inline]
 __do_sys_fallocate fs/open.c:371 [inline]
 __se_sys_fallocate fs/open.c:369 [inline]
 __x64_sys_fallocate+0xc0/0x110 fs/open.c:369
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9d53a7f749
RSP: 002b:00007ffc05b89e68 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 00007f9d53cd5fa0 RCX: 00007f9d53a7f749
RDX: 0000000000002000 RSI: 0000000000000010 RDI: 0000000000000003
RBP: 00007f9d53b03f91 R08: 0000000000000000 R09: 0000000000000000
R10: 000000100007c000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9d53cd5fa0 R14: 00007f9d53cd5fa0 R15: 0000000000000004
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/0:0/9:
 #0: ffff88813ff55138 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
 #0: ffff88813ff55138 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
 #1: ffffc900000e7ba0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
 #1: ffffc900000e7ba0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
 #2: ffff88804746d260 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x224/0x3e0 drivers/net/netdevsim/fib.c:1490
3 locks held by kworker/u8:1/13:
4 locks held by pr/legacy/17:
1 lock held by khungtaskd/38:
 #0: ffffffff8d5aa880 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8d5aa880 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
 #0: ffffffff8d5aa880 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:2/43:
 #0: ffff88814d2a3138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
 #0: ffff88814d2a3138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
 #1: ffffc90000b47ba0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
 #1: ffffc90000b47ba0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
 #2: ffffffff8e863d78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #2: ffffffff8e863d78 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x119/0x15a0 net/ipv6/addrconf.c:4194
3 locks held by kworker/u8:5/156:
 #0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
 #0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
 #1: ffffc90003a67ba0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
 #1: ffffc90003a67ba0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
 #2: ffffffff8e863d78 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
3 locks held by kworker/u8:8/1429:
2 locks held by kworker/1:3/1812:
2 locks held by getty/5563:
 #0: ffff88823bf328a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1400 drivers/tty/n_tty.c:2222
2 locks held by syz.1.18/6078:
1 lock held by syz.2.19/6079:
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_fallocate+0x263/0x550 block/fops.c:911
1 lock held by syz.3.20/6081:
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_fallocate+0x263/0x550 block/fops.c:911
1 lock held by syz.4.21/6082:
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_fallocate+0x263/0x550 block/fops.c:911
1 lock held by syz.5.22/6210:
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_fallocate+0x263/0x550 block/fops.c:911
1 lock held by syz.6.23/6215:
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_fallocate+0x263/0x550 block/fops.c:911
1 lock held by syz.7.24/6218:
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_fallocate+0x263/0x550 block/fops.c:911
1 lock held by syz.9.26/6219:
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_fallocate+0x263/0x550 block/fops.c:911
1 lock held by syz.8.25/6222:
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_fallocate+0x263/0x550 block/fops.c:911
1 lock held by syz.0.27/6297:
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_fallocate+0x263/0x550 block/fops.c:911
1 lock held by syz.1.28/6316:
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_fallocate+0x263/0x550 block/fops.c:911
1 lock held by syz.2.29/6335:
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_fallocate+0x263/0x550 block/fops.c:911
1 lock held by syz.3.30/6336:
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_fallocate+0x263/0x550 block/fops.c:911
1 lock held by syz.4.31/6337:
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_fallocate+0x263/0x550 block/fops.c:911
1 lock held by syz.6.33/6438:
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_fallocate+0x263/0x550 block/fops.c:911
1 lock held by syz.5.32/6480:
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_fallocate+0x263/0x550 block/fops.c:911
1 lock held by syz.7.34/6481:
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_fallocate+0x263/0x550 block/fops.c:911
1 lock held by syz.8.35/6482:
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_fallocate+0x263/0x550 block/fops.c:911
1 lock held by syz.9.36/6483:
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
 #0: ffff8881498a2228 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_fallocate+0x263/0x550 block/fops.c:911
3 locks held by syz-executor/6486:
1 lock held by syz-executor/6498:
 #0: ffffffff8e863d78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff8e863d78 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_newaddr+0x5b7/0xd20 net/ipv6/addrconf.c:5027
8 locks held by syz-executor/6501:
4 locks held by syz-executor/6508:
 #0: ffff888033f42480 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3113 [inline]
 #0: ffff888033f42480 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x217/0xb40 fs/read_write.c:682
 #1: ffff88805a3e0c78 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1df/0x540 fs/kernfs/file.c:343
 #2: ffff88814574c008 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff88814574c008 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x232/0x540 fs/kernfs/file.c:344
 #3: ffffffff8e0f4738 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x12c/0x6f0 drivers/net/netdevsim/bus.c:184
4 locks held by syz-executor/6509:
 #0: ffff888033f42480 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3113 [inline]
 #0: ffff888033f42480 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x217/0xb40 fs/read_write.c:682
 #1: ffff88802d59f878 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1df/0x540 fs/kernfs/file.c:343
 #2: ffff88814574c008 (kn->active#58){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff88814574c008 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x232/0x540 fs/kernfs/file.c:344
 #3: ffffffff8e0f4738 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x12c/0x6f0 drivers/net/netdevsim/bus.c:184

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
 watchdog+0xf60/0xfa0 kernel/hung_task.c:495
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 17 Comm: pr/legacy Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:400
Code: e8 de f6 b9 fc 44 89 f9 d3 e3 49 83 ee 80 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 2f b8 1b fd 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f e9 ca b8 bf 05 cc 44 89 f9 80 e1 07
RSP: 0018:ffffc90000167870 EFLAGS: 00000202
RAX: 1ffffffff31d2700 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffffff98e94110 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff8504b610 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff98e93e80 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888126df4000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055a4b493d7a0 CR3: 0000000030eb8000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 serial_in drivers/tty/serial/8250/8250.h:137 [inline]
 serial_lsr_in drivers/tty/serial/8250/8250.h:159 [inline]
 wait_for_lsr+0x1aa/0x2f0 drivers/tty/serial/8250/8250_port.c:1961
 fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3234 [inline]
 serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3257 [inline]
 serial8250_console_write+0x11bd/0x1b40 drivers/tty/serial/8250/8250_port.c:3342
 console_emit_next_record kernel/printk/printk.c:3091 [inline]
 console_flush_all+0x666/0xb40 kernel/printk/printk.c:3199
 __console_flush_and_unlock+0x9b/0x160 kernel/printk/printk.c:3258
 legacy_kthread_func+0x13b/0x1a0 kernel/printk/printk.c:3611
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>