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INFO: task hung in blk_trace_ioctl (2)

Status: upstream: reported syz repro on 2025/11/13 16:40
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+4bf530af3aab8c245dab@syzkaller.appspotmail.com
First crash: 32d, last: 16d
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2025/11/15 upstream (ToT) f824272b6e3f syz [report] INFO: task hung in blk_trace_setup
▶ ▼ Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in blk_trace_ioctl block trace 1 3 2566d 2646d 0/29 auto-closed as invalid on 2019/06/04 08:29
upstream INFO: task hung in blk_trace_ioctl (2) trace block 1 4 2166d 2276d 0/29 auto-closed as invalid on 2020/04/09 23:38
upstream INFO: task hung in blk_trace_ioctl (3) block trace 1 2 1476d 1541d 0/29 closed as invalid on 2022/02/07 19:19
linux-5.15 INFO: task hung in blk_trace_ioctl 1 1 135d 135d 0/3 auto-obsoleted due to no activity on 2025/11/10 20:19
upstream INFO: task hung in blk_trace_ioctl (4) block trace 1 C done 65 1d15h 746d 0/29 upstream: reported C repro on 2023/11/30 21:17
linux-4.19 INFO: task hung in blk_trace_ioctl 1 1 1230d 1230d 0/1 auto-obsoleted due to no activity on 2022/12/01 07:14
▶ ▼ Last patch testing requests (1)
Created Duration User Patch Repo Result
2025/11/29 13:12 14m retest repro linux-5.15.y report log

Sample crash report:
INFO: task syz.5.22:4681 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.22        state:D stack:28736 pid: 4681 ppid:  4450 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 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+0xc71/0x2390 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_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
 blkdev_common_ioctl+0xfbe/0x1c70 block/ioctl.c:532
 blkdev_ioctl+0x295/0x690 block/ioctl.c:598
 block_ioctl+0xac/0xf0 block/fops.c:496
 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: 0033:0x7f7fbd6d76c9
RSP: 002b:00007f7fbcd25038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f7fbd92e090 RCX: 00007f7fbd6d76c9
RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000004
RBP: 00007f7fbd759f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7fbd92e128 R14: 00007f7fbd92e090 R15: 00007ffc0faa3818
 </TASK>
INFO: task syz.8.25:4688 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.25        state:D stack:27872 pid: 4688 ppid:  4469 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 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+0xc71/0x2390 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_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
 blkdev_ioctl+0x153/0x690 block/ioctl.c:593
 block_ioctl+0xac/0xf0 block/fops.c:496
 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: 0033:0x7f4681ad46c9
RSP: 002b:00007f4681143038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f4681d2afa0 RCX: 00007f4681ad46c9
RDX: 0000200000000380 RSI: 00000000c0481273 RDI: 0000000000000004
RBP: 00007f4681b56f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4681d2b038 R14: 00007f4681d2afa0 R15: 00007ffcca705ae8
 </TASK>
INFO: task syz.8.25:4691 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.25        state:D stack:28800 pid: 4691 ppid:  4469 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 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+0xc71/0x2390 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_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
 blkdev_common_ioctl+0xfbe/0x1c70 block/ioctl.c:532
 blkdev_ioctl+0x295/0x690 block/ioctl.c:598
 block_ioctl+0xac/0xf0 block/fops.c:496
 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: 0033:0x7f4681ad46c9
RSP: 002b:00007f4681122038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f4681d2b090 RCX: 00007f4681ad46c9
RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000004
RBP: 00007f4681b56f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4681d2b128 R14: 00007f4681d2b090 R15: 00007ffcca705ae8
 </TASK>
INFO: task syz.9.26:4693 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.9.26        state:D stack:27872 pid: 4693 ppid:  4470 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 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+0xc71/0x2390 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_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
 blkdev_ioctl+0x153/0x690 block/ioctl.c:593
 block_ioctl+0xac/0xf0 block/fops.c:496
 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: 0033:0x7f5871bd26c9
RSP: 002b:00007f5871241038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f5871e28fa0 RCX: 00007f5871bd26c9
RDX: 0000200000000380 RSI: 00000000c0481273 RDI: 0000000000000004
RBP: 00007f5871c54f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5871e29038 R14: 00007f5871e28fa0 R15: 00007ffc45b74e08
 </TASK>
INFO: task syz.9.26:4694 blocked for more than 145 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.9.26        state:D stack:28800 pid: 4694 ppid:  4470 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 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+0xc71/0x2390 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_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
 blkdev_common_ioctl+0xfbe/0x1c70 block/ioctl.c:532
 blkdev_ioctl+0x295/0x690 block/ioctl.c:598
 block_ioctl+0xac/0xf0 block/fops.c:496
 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: 0033:0x7f5871bd26c9
RSP: 002b:00007f5871220038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f5871e29090 RCX: 00007f5871bd26c9
RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000004
RBP: 00007f5871c54f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5871e29128 R14: 00007f5871e29090 R15: 00007ffc45b74e08
 </TASK>
INFO: task syz.7.24:4699 blocked for more than 145 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.24        state:D stack:27872 pid: 4699 ppid:  4468 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 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+0xc71/0x2390 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_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
 blkdev_ioctl+0x153/0x690 block/ioctl.c:593
 block_ioctl+0xac/0xf0 block/fops.c:496
 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: 0033:0x7fd9e31736c9
RSP: 002b:00007fd9e27e2038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fd9e33c9fa0 RCX: 00007fd9e31736c9
RDX: 0000200000000380 RSI: 00000000c0481273 RDI: 0000000000000004
RBP: 00007fd9e31f5f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd9e33ca038 R14: 00007fd9e33c9fa0 R15: 00007ffd30117348
 </TASK>
INFO: task syz.7.24:4702 blocked for more than 146 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.24        state:D stack:28800 pid: 4702 ppid:  4468 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 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+0xc71/0x2390 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_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
 blkdev_common_ioctl+0xfbe/0x1c70 block/ioctl.c:532
 blkdev_ioctl+0x295/0x690 block/ioctl.c:598
 block_ioctl+0xac/0xf0 block/fops.c:496
 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: 0033:0x7fd9e31736c9
RSP: 002b:00007fd9e27c1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fd9e33ca090 RCX: 00007fd9e31736c9
RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000004
RBP: 00007fd9e31f5f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd9e33ca128 R14: 00007fd9e33ca090 R15: 00007ffd30117348
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/0:1/13:
 #0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
 #1: ffffc90000d27d00 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
 #2: ffff88807dc37400 (&nsim_dev->port_list_lock){+.+.}-{3:3}, at: nsim_dev_trap_report_work+0x56/0xb40 drivers/net/netdevsim/dev.c:757
1 lock held by khungtaskd/27:
 #0: ffffffff8c11c760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by getty/3944:
 #0: ffff88814c973098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc900026562e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
3 locks held by kworker/u4:5/4367:
3 locks held by kworker/0:8/4371:
 #0: ffff88802ac37538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
 #1: ffffc9000366fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
 #2: ffffffff8d238988 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1520 net/ipv6/addrconf.c:4110
2 locks held by kworker/0:10/4373:
 #0: ffff888016872138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
 #1: ffffc9000368fd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
2 locks held by syz.5.22/4680:
1 lock held by syz.5.22/4681:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.8.25/4688:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.8.25/4691:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.9.26/4693:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.9.26/4694:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.7.24/4699:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.7.24/4702:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.1.27/5053:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.1.27/5056:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.2.28/5059:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.2.28/5061:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.3.30/5176:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.3.30/5178:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.0.29/5173:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.0.29/5177:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.4.31/5199:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.4.31/5201:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.6.33/5356:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.6.33/5357:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.5.32/5359:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.5.32/5360:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.7.34/5411:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.7.34/5412:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.8.35/5414:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.8.35/5415:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.9.36/5417:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.9.36/5418:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.1.37/5461:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.1.37/5464:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.2.38/5476:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.2.38/5477:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.0.39/5516:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.0.39/5517:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.3.40/5533:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.3.40/5534:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.4.41/5537:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.4.41/5540:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.6.42/5571:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.6.42/5572:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.5.43/5595:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.5.43/5596:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.7.44/5634:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.7.44/5635:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.8.45/5685:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.8.45/5687:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.9.46/5697:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.9.46/5698:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.1.47/5710:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.1.47/5711:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.2.48/5725:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.2.48/5726:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.0.49/5740:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.0.49/5743:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz-executor/5776:
 #0: ffffffff8d238988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d238988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7a5/0xe90 net/core/rtnetlink.c:5681
1 lock held by syz.3.50/5794:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.3.50/5799:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
8 locks held by syz-executor/5795:
 #0: ffff88807f29c460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x28a/0xd00 fs/read_write.c:590
 #1: ffff88807cf0e488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e5/0x4c0 fs/kernfs/file.c:287
 #2: ffff888023275e88 (kn->active#362){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x208/0x4c0 fs/kernfs/file.c:288
 #3: ffffffff8cb725e8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xce/0x380 drivers/net/netdevsim/bus.c:344
 #4: ffff88817a5f0178 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline]
 #4: ffff88817a5f0178 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1044 [inline]
 #4: ffff88817a5f0178 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xb0/0x750 drivers/base/dd.c:1259
 #5: ffff88807dc37400 (&nsim_dev->port_list_lock){+.+.}-{3:3}, at: nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1359 [inline]
 #5: ffff88807dc37400 (&nsim_dev->port_list_lock){+.+.}-{3:3}, at: nsim_dev_reload_destroy+0x115/0x240 drivers/net/netdevsim/dev.c:1561
 #6: ffffffff8d238988 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x3b/0x150 drivers/net/netdevsim/netdev.c:381
 #7: ffffffff8c1211e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
 #7: ffffffff8c1211e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x347/0x6b0 kernel/rcu/tree_exp.h:845
2 locks held by syz-executor/5812:
 #0: ffffffff8d22cd10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x32e/0x5b0 net/core/net_namespace.c:499
 #1: ffffffff8d238988 (rtnl_mutex){+.+.}-{3:3}, at: ip_tunnel_init_net+0x224/0x6b0 net/ipv4/ip_tunnel.c:1083
1 lock held by syz.4.51/5816:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735
1 lock held by syz.4.51/5817:
 #0: ffff88802103a288 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0x108/0x4f0 kernel/trace/blktrace.c:735

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

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 10/02/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x397/0x3d0 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: 4680 Comm: syz.5.22 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:check_region_inline mm/kasan/generic.c:169 [inline]
RIP: 0010:kasan_check_range+0xd/0x290 mm/kasan/generic.c:189
Code: c3 0f 0b b8 ea ff ff ff c3 0f 0b b8 ea ff ff ff c3 00 00 cc cc 00 00 cc cc 00 00 cc cc b0 01 48 85 f6 0f 84 a4 01 00 00 41 57 <41> 56 53 49 89 f8 49 01 f0 0f 82 57 02 00 00 49 89 f8 49 c1 e8 2f
RSP: 0018:ffffc90002fff470 EFLAGS: 00000202
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff815bfaab
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8d699d28
RBP: ffffc90002fff5a0 R08: 0000000000000001 R09: 0000000000000000
R10: fffffbfff1ff7c1b R11: 1ffffffff1ff7c1a R12: ffffffff8c1ece60
R13: 1ffff920005ffe9c R14: 0000000000000000 R15: dffffc0000000000
FS:  00007f7fbcd466c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055e5e2973b68 CR3: 0000000199761000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 cpumask_test_cpu include/linux/cpumask.h:344 [inline]
 cpu_online include/linux/cpumask.h:895 [inline]
 trace_lock_acquire include/trace/events/lock.h:13 [inline]
 lock_acquire+0xbb/0x3f0 kernel/locking/lockdep.c:5594
 fs_reclaim_acquire+0x91/0x100 mm/page_alloc.c:4597
 prepare_alloc_pages+0x15a/0x5f0 mm/page_alloc.c:5258
 __alloc_pages+0x10e/0x470 mm/page_alloc.c:5476
 __get_free_pages+0x8/0x30 mm/page_alloc.c:5524
 kasan_populate_vmalloc_pte+0x21/0xc0 mm/kasan/shadow.c:266
 apply_to_pte_range mm/memory.c:2573 [inline]
 apply_to_pmd_range mm/memory.c:2617 [inline]
 apply_to_pud_range mm/memory.c:2653 [inline]
 apply_to_p4d_range mm/memory.c:2689 [inline]
 __apply_to_page_range+0x983/0xd10 mm/memory.c:2725
 alloc_vmap_area+0x19f7/0x1b20 mm/vmalloc.c:1572
 __get_vm_area_node+0x14f/0x2d0 mm/vmalloc.c:2430
 get_vm_area_caller mm/vmalloc.c:2473 [inline]
 vmap+0xd4/0x290 mm/vmalloc.c:2758
 relay_alloc_buf kernel/relay.c:129 [inline]
 relay_create_buf kernel/relay.c:165 [inline]
 relay_open_buf+0x3e8/0xda0 kernel/relay.c:387
 relay_open+0x371/0x8e0 kernel/relay.c:520
 do_blk_trace_setup+0x559/0x9d0 kernel/trace/blktrace.c:559
 __blk_trace_setup kernel/trace/blktrace.c:599 [inline]
 blk_trace_ioctl+0x404/0x4f0 kernel/trace/blktrace.c:740
 blkdev_ioctl+0x153/0x690 block/ioctl.c:593
 block_ioctl+0xac/0xf0 block/fops.c:496
 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: 0033:0x7f7fbd6d76c9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7fbcd46038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f7fbd92dfa0 RCX: 00007f7fbd6d76c9
RDX: 0000200000000380 RSI: 00000000c0481273 RDI: 0000000000000004
RBP: 00007f7fbd759f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7fbd92e038 R14: 00007f7fbd92dfa0 R15: 00007ffc0faa3818
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/13 16:39 linux-5.15.y cc5ec8769306 07e030de .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in blk_trace_ioctl
* Struck through repros no longer work on HEAD.