syzbot


INFO: task hung in blk_trace_setup (2)

Status: upstream: reported syz repro on 2026/05/09 00:50
Reported-by: syzbot+d5217616605057b24ac7@syzkaller.appspotmail.com
First crash: 2d06h, last: 2d06h
Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: task hung in blk_trace_setup 1 1 225d 225d 0/3 auto-obsoleted due to no activity on 2026/01/05 22:14
upstream INFO: task hung in blk_trace_setup (2) block trace 1 1 2242d 2242d 0/29 auto-closed as invalid on 2020/06/18 13:53
upstream INFO: task hung in blk_trace_setup (4) block trace 1 syz done error 23 16d 299d 0/29 upstream: reported syz repro on 2025/07/15 17:43
upstream INFO: task hung in blk_trace_setup (3) block trace 1 1 787d 787d 0/29 auto-obsoleted due to no activity on 2024/06/13 01:38
upstream INFO: task hung in blk_trace_setup trace block 1 1 2614d 2614d 0/29 auto-closed as invalid on 2019/09/10 19:17

Sample crash report:
INFO: task syz.0.17:4416 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17        state:D stack:27504 pid: 4416 ppid:  4332 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xcfc/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
 sg_ioctl_common drivers/scsi/sg.c:1119 [inline]
 sg_ioctl+0xe52/0x1fc0 drivers/scsi/sg.c:1161
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc59b6e5dd9
RSP: 002b:00007fc59ad47028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fc59b95efa0 RCX: 00007fc59b6e5dd9
RDX: 0000200000000040 RSI: 00000000c0481273 RDI: 0000000000000003
RBP: 00007fc59b77bd69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc59b95f038 R14: 00007fc59b95efa0 R15: 00007fffda169678
 </TASK>
INFO: task syz.0.17:4417 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17        state:D
 stack:29072 pid: 4417 ppid:  4332 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xcfc/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
 sg_ioctl_common drivers/scsi/sg.c:1127 [inline]
 sg_ioctl+0x426/0x1fc0 drivers/scsi/sg.c:1161
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc59b6e5dd9
RSP: 002b:00007fc59ad26028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fc59b95f090 RCX: 00007fc59b6e5dd9
RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000003
RBP: 00007fc59b77bd69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc59b95f128 R14: 00007fc59b95f090 R15: 00007fffda169678
 </TASK>
INFO: task syz.2.19:4419 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.19        state:D stack:27600 pid: 4419 ppid:  4345 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xcfc/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
 sg_ioctl_common drivers/scsi/sg.c:1119 [inline]
 sg_ioctl+0xe52/0x1fc0 drivers/scsi/sg.c:1161
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fa022e10dd9
RSP: 002b:00007fa022472028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fa023089fa0 RCX: 00007fa022e10dd9
RDX: 0000200000000040 RSI: 00000000c0481273 RDI: 0000000000000003
RBP: 00007fa022ea6d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa02308a038 R14: 00007fa023089fa0 R15: 00007ffd33e8ea08
 </TASK>
INFO: task syz.2.19:4420 blocked for more than 145 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.19        state:D stack:29072 pid: 4420 ppid:  4345 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xcfc/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
 sg_ioctl_common drivers/scsi/sg.c:1127 [inline]
 sg_ioctl+0x426/0x1fc0 drivers/scsi/sg.c:1161
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fa022e10dd9
RSP: 002b:00007fa022451028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fa02308a090 RCX: 00007fa022e10dd9
RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000003
RBP: 00007fa022ea6d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa02308a128 R14: 00007fa02308a090 R15: 00007ffd33e8ea08
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c31eb20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
3 locks held by kworker/u4:1/144:
1 lock held by klogd/3550:
2 locks held by getty/3946:
 #0: ffff88802c2c5098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc900021ce2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158
3 locks held by kworker/1:13/4319:
 #0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: 
ffffc900031afd00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffff88820f201240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x26a/0x33e0 drivers/net/netdevsim/fib.c:1480
3 locks held by kworker/1:21/4327:
 #0: ffff88814c880138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc9000322fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffffffff8d43d3c8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xca/0x1540 net/ipv6/addrconf.c:4110
2 locks held by syz.4.21/4414:
1 lock held by syz.0.17/4416:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.0.17/4417:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.2.19/4419:
 #0: ffff888022370608
 (
&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.2.19/4420:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.6.23/4461:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.6.23/4462:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.5.22/4464:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.5.22/4465:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
3 locks held by kworker/0:7/4521:
 #0: ffff88814c880138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc90003e5fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffffffff8d43d3c8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xca/0x1540 net/ipv6/addrconf.c:4110
1 lock held by syz.8.25/4523:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.8.25/4524:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.7.24/4526:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.7.24/4529:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.9.26/4528:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.9.26/4530:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.3.28/4558:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.3.28/4559:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.1.27/4561:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.1.27/4562:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.0.29/4599:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.0.29/4600:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.2.30/4617:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.2.30/4619:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.4.31/4620:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.4.31/4621:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.6.33/4660:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.6.33/4661:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.5.32/4663:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.5.32/4664:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.8.34/4694:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.8.34/4695:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.9.36/4725:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.9.36/4728:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}
, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.7.35/4730:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.7.35/4733:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.1.37/4756:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.1.37/4759:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.3.38/4768:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.3.38/4769:
 #0: ffff888022370608 (
&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.0.39/4776:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.0.39/4779:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.2.40/4810:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.2.40/4812:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.4.41/4827:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.4.41/4830:
 #0: 
ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.6.42/4864:
 #0: ffff888022370608
 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.6.42/4866:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.5.43/4871:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.5.43/4872:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.8.44/4895:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.8.44/4897:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.9.45/4926:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.9.45/4927:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.7.46/4941:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.7.46/4942:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
3 locks held by syz-executor/4955:
1 lock held by syz.1.47/4961:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.1.47/4963:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz.3.48/4970:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0xae/0x1f0 kernel/trace/blktrace.c:616
1 lock held by syz.3.48/4971:
 #0: ffff888022370608 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1c/0x40 kernel/trace/blktrace.c:374
1 lock held by syz-executor/4972:
 #0: ffffffff8d43d3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d43d3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7ee/0xf30 net/core/rtnetlink.c:5684
2 locks held by syz-executor/4984:
 #0: ffffffff8d4314d0
 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x32e/0x5b0 net/core/net_namespace.c:499
 #1: ffffffff8d43d3c8 (rtnl_mutex){+.+.}-{3:3}, at: ip_tunnel_init_net+0x234/0x6f0 net/ipv4/ip_tunnel.c:1083

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xe0f/0xe50 kernel/hung_task.c:369
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4414 Comm: syz.4.21 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:preempt_count_add+0xc3/0x190 kernel/sched/core.c:5516
Code: 00 65 4c 8b 35 7e fe af 7e 49 81 c6 e8 14 00 00 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 81 e2 6b 00 49 89 1e 5b <41> 5e 41 5f c3 89 fb e8 e1 68 8e 02 89 df 85 c0 74 9b 48 c7 c0 c8
RSP: 0018:ffffc90003f2f770 EFLAGS: 00000246
RAX: 1ffff110052d0dc5 RBX: ffffc90003f2f848 RCX: ffffffff962dbf00
RDX: dffffc0000000000 RSI: ffffffff817a3587 RDI: ffffffff81351d2c
RBP: ffffc90003f2f890 R08: ffffc90003f2f910 R09: 0000000000000003
R10: dffffc0000000000 R11: fffff520007e5f15 R12: ffffffff817a3587
R13: ffffc90003f2fca0 R14: ffff888029686e28 R15: dffffc0000000000
FS:  00007f96746b96c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055c77570ae40 CR3: 000000008ea83000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 unwind_next_frame+0xac/0x1d90 arch/x86/kernel/unwind_orc.c:433
 arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122
 save_stack+0x121/0x230 mm/page_owner.c:119
 __reset_page_owner+0x51/0x180 mm/page_owner.c:140
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1340 [inline]
 free_pcp_prepare mm/page_alloc.c:1391 [inline]
 free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317
 free_unref_page+0x8f/0x2a0 mm/page_alloc.c:3396
 relay_destroy_buf+0x10e/0x3a0 kernel/relay.c:204
 relay_remove_buf kernel/relay.c:224 [inline]
 kref_put include/linux/kref.h:65 [inline]
 relay_close_buf kernel/relay.c:433 [inline]
 relay_close+0x3a7/0x6d0 kernel/relay.c:769
 blk_trace_free+0x3c/0x110 kernel/trace/blktrace.c:315
 blk_trace_cleanup kernel/trace/blktrace.c:351 [inline]
 __blk_trace_remove+0xda/0x170 kernel/trace/blktrace.c:365
 blk_trace_remove+0x24/0x40 kernel/trace/blktrace.c:375
 sg_ioctl_common drivers/scsi/sg.c:1127 [inline]
 sg_ioctl+0x426/0x1fc0 drivers/scsi/sg.c:1161
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f9675078dd9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f96746b9028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f96752f2090 RCX: 00007f9675078dd9
RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000003
RBP: 00007f967510ed69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f96752f2128 R14: 00007f96752f2090 R15: 00007fff908095b8
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/09 00:49 linux-5.15.y 7e75ef31ddc9 b2988c17 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in blk_trace_setup
* Struck through repros no longer work on HEAD.