syzbot


INFO: task hung in del_device_store

Status: upstream: reported C repro on 2025/11/21 00:14
Bug presence: origin:upstream
Labels: missing-backport
[Documentation on labels]
Reported-by: syzbot+9e1ed60c6f288bc7b286@syzkaller.appspotmail.com
First crash: 214d, last: 1d04h
Fix bisection: failed (error log, bisect log)
  
Bug presence (3)
Date Name Commit Repro Result
2026/05/18 linux-6.6.y (ToT) eac8889a3a1c C [report] INFO: task hung in corrupted
2025/11/25 upstream (ToT) 30f09200cc4a C [report] INFO: task hung in corrupted
2026/05/18 upstream (ToT) 4d3a2a466b8d C Didn't crash
Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: task hung in del_device_store (2) origin:upstream 1 syz error 9 2d15h 168d 0/3 upstream: reported syz repro on 2026/01/05 21:06
linux-5.15 INFO: task hung in del_device_store 1 42 339d 711d 0/3 auto-obsoleted due to no activity on 2025/10/26 20:35
linux-5.15 INFO: task hung in del_device_store (2) 1 9 69d 214d 0/3 upstream: reported on 2025/11/20 15:49
linux-6.1 INFO: task hung in del_device_store 1 31 306d 718d 0/3 auto-obsoleted due to no activity on 2025/11/28 01:25
upstream INFO: task hung in del_device_store prio:low net 1 C error 2148 now 1205d 0/29 upstream: reported C repro on 2023/03/05 17:44
Fix bisection attempts (2)
Created Duration User Patch Repo Result
2026/02/13 21:03 6m bisect fix linux-6.6.y error job log
2025/12/25 17:29 2h16m bisect fix linux-6.6.y OK (0) job log log

Sample crash report:
INFO: task syz-executor:5894 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:22344 pid:5894  ppid:1      flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0x15ae/0x4660 kernel/sched/core.c:6700
 schedule+0xbd/0x170 kernel/sched/core.c:6774
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6833
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x673/0xc80 kernel/locking/mutex.c:747
 del_device_store+0xd7/0x370 drivers/net/netdevsim/bus.c:209
 kernfs_fop_write_iter+0x3a4/0x520 fs/kernfs/file.c:352
 call_write_iter include/linux/fs.h:2018 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x474/0x9a0 fs/read_write.c:584
 ksys_write+0x151/0x260 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f366b95d68e
RSP: 002b:00007ffe78784a48 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000055559077b500 RCX: 00007f366b95d68e
RDX: 0000000000000001 RSI: 00007ffe78784ad0 RDI: 0000000000000005
RBP: 00007f366ba336f2 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffe78784ad0 R14: 00007f366c744620 R15: 0000000000000003
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/28:
 #0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
 #0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
 #0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
2 locks held by kworker/u4:2/41:
2 locks held by kworker/1:2/969:
 #0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
 #0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
 #1: ffffc90004017d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
 #1: ffffc90004017d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
4 locks held by kworker/u4:9/4988:
 #0: ffff88801a254938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
 #0: ffff88801a254938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
 #1: ffffc9000fdf7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
 #1: ffffc9000fdf7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
 #2: ffffffff8e3b2e50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x14c/0xbb0 net/core/net_namespace.c:606
 #3: ffffffff8e3bfe48 (rtnl_mutex){+.+.}-{3:3}, at: ip6_tnl_exit_batch_net+0xcc/0x630 net/ipv6/ip6_tunnel.c:2297
3 locks held by kworker/0:3/5156:
 #0: ffff888017c71d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
 #0: ffff888017c71d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
 #1: ffffc900033e7d00 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
 #1: ffffc900033e7d00 ((reg_check_chans).work){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
 #2: ffffffff8e3bfe48 (rtnl_mutex){+.+.}-{3:3}, at: reg_check_chans_work+0x92/0xd90 net/wireless/reg.c:2463
2 locks held by dhcpcd/5436:
 #0: ffff888025ae1690 (nlk_cb_mutex-ROUTE){+.+.}-{3:3}, at: __netlink_dump_start+0xf4/0x7a0 net/netlink/af_netlink.c:2341
 #1: ffffffff8e3bfe48 (rtnl_mutex){+.+.}-{3:3}, at: netlink_dump+0x77c/0xec0 net/netlink/af_netlink.c:2268
2 locks held by getty/5527:
 #0: ffff88814c8540a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x428/0x1370 drivers/tty/n_tty.c:2217
4 locks held by syz-executor/5894:
 #0: ffff88802081e418 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580
 #1: ffff8880595dec88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1dc/0x520 fs/kernfs/file.c:343
 #2: ffff888024b60e90 (kn->active#59){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff888024b60e90 (kn->active#59){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x236/0x520 fs/kernfs/file.c:344
 #3: ffffffff8dca0608 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xd7/0x370 drivers/net/netdevsim/bus.c:209
7 locks held by syz-executor/5896:
 #0: ffff88802081e418 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580
 #1: ffff888024737488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1dc/0x520 fs/kernfs/file.c:343
 #2: ffff888024b60e90 (kn->active#59){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff888024b60e90 (kn->active#59){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x236/0x520 fs/kernfs/file.c:344
 #3: ffffffff8dca0608 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xd7/0x370 drivers/net/netdevsim/bus.c:209
 #4: ffff88802f836130 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1094 [inline]
 #4: ffff88802f836130 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1175 [inline]
 #4: ffff88802f836130 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xa7/0x6f0 drivers/base/dd.c:1372
 #5: ffff88802f837250 (&devlink->lock_key){+.+.}-{3:3}, at: nsim_drv_remove+0x50/0x170 drivers/net/netdevsim/dev.c:1676
 #6: ffffffff8e3bfe48 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x3f/0x180 drivers/net/netdevsim/netdev.c:417
4 locks held by syz.0.17/5944:
2 locks held by kworker/1:5/5967:
 #0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
 #0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
 #1: ffffc90003537d00 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
 #1: ffffc90003537d00 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
1 lock held by syz-executor/5973:
 #0: ffffffff8e3bfe48 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline]
 #0: ffffffff8e3bfe48 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x41/0x1c0 drivers/net/tun.c:3514
1 lock held by syz-executor/5974:
 #0: ffffffff8e3bfe48 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline]
 #0: ffffffff8e3bfe48 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x41/0x1c0 drivers/net/tun.c:3514
5 locks held by syz-executor/5989:
 #0: ffff88805bf98e70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:521 [inline]
 #0: ffff88805bf98e70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x212/0x500 net/bluetooth/hci_core.c:2709
 #1: ffff88805bf980b8 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x552/0x1130 net/bluetooth/hci_sync.c:5293
 #2: ffffffff8e52d3c8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2011 [inline]
 #2: ffffffff8e52d3c8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0x99/0x220 net/bluetooth/hci_conn.c:2564
 #3: ffff88802ba85b38 (&conn->lock#2){+.+.}-{3:3}, at: l2cap_conn_del+0x6f/0x670 net/bluetooth/l2cap_core.c:1761
 #4: ffffffff8d137778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline]
 #4: ffffffff8d137778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3da/0x880 kernel/rcu/tree_exp.h:1004
2 locks held by syz-executor/6053:
 #0: ffffffff8e3b2e50 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x342/0x5d0 net/core/net_namespace.c:516
 #1: ffffffff8e3bfe48 (rtnl_mutex){+.+.}-{3:3}, at: register_nexthop_notifier+0x88/0x240 net/ipv4/nexthop.c:3636
2 locks held by syz-executor/6054:
 #0: ffffffff8e3b2e50 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x342/0x5d0 net/core/net_namespace.c:516
 #1: ffffffff8e3bfe48 (rtnl_mutex){+.+.}-{3:3}, at: register_netdev+0x13/0x50 net/core/dev.c:10448
2 locks held by syz-executor/6067:
 #0: ffffffff8e3b2e50 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x342/0x5d0 net/core/net_namespace.c:516
 #1: ffffffff8e3bfe48 (rtnl_mutex){+.+.}-{3:3}, at: register_nexthop_notifier+0x88/0x240 net/ipv4/nexthop.c:3636
2 locks held by syz-executor/6068:
 #0: ffffffff8e3b2e50 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x342/0x5d0 net/core/net_namespace.c:516
 #1: ffffffff8e3bfe48 (rtnl_mutex){+.+.}-{3:3}, at: register_nexthop_notifier+0x88/0x240 net/ipv4/nexthop.c:3636
1 lock held by dhcpcd/6074:
 #0: ffff88806bd3d620 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
 #0: ffff88806bd3d620 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline]
 #0: ffff88806bd3d620 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x82/0x210 net/socket.c:1421
1 lock held by dhcpcd/6075:
 #0: ffff88806bd30820 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
 #0: ffff88806bd30820 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline]
 #0: ffff88806bd30820 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x82/0x210 net/socket.c:1421
1 lock held by dhcpcd/6076:
 #0: ffff88806bd3be20 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
 #0: ffff88806bd3be20 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline]
 #0: ffff88806bd3be20 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x82/0x210 net/socket.c:1421
1 lock held by dhcpcd/6077:
 #0: ffff8880786fbe20 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
 #0: ffff8880786fbe20 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline]
 #0: ffff8880786fbe20 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x82/0x210 net/socket.c:1421
1 lock held by dhcpcd/6078:
 #0: ffff8880786fdc20 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
 #0: ffff8880786fdc20 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline]
 #0: ffff8880786fdc20 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x82/0x210 net/socket.c:1421
1 lock held by dhcpcd/6079:
 #0: ffff88806bd30220 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
 #0: ffff88806bd30220 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline]
 #0: ffff88806bd30220 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x82/0x210 net/socket.c:1421

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

NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
 watchdog+0xf59/0xfa0 kernel/hung_task.c:379
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 5944 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:get_current arch/x86/include/asm/current.h:41 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:244 [inline]
RIP: 0010:__sanitizer_cov_trace_cmp4+0x8/0x90 kernel/kcov.c:287
Code: 08 02 00 00 00 48 89 7c 11 10 48 89 74 11 18 48 89 44 11 20 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 15 60 d1 7c 7e 65 8b 0d 61 d1 7c 7e 81 e1 00 01 ff 00 74
RSP: 0018:ffffc90000006f48 EFLAGS: 00000007
RAX: ffffffff813b25e6 RBX: ffffffff81000000 RCX: ffff88807b3d0000
RDX: 0000000000000100 RSI: 0000000000008d50 RDI: 000000000009c000
RBP: 000000000009c000 R08: ffff88807b3d0000 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000100 R12: ffffc900000078d0
R13: 000000000009c001 R14: 0000000000008d50 R15: 0000000000000001
FS:  000055558a1ff500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffcede16d68 CR3: 0000000021287000 CR4: 00000000003506f0
Call Trace:
 <IRQ>
 orc_find arch/x86/kernel/unwind_orc.c:211 [inline]
 unwind_next_frame+0x216/0x2990 arch/x86/kernel/unwind_orc.c:494
 __unwind_start+0x5bb/0x730 arch/x86/kernel/unwind_orc.c:760
 unwind_start arch/x86/include/asm/unwind.h:64 [inline]
 perf_callchain_kernel+0x2a2/0x690 arch/x86/events/core.c:-1
 get_perf_callchain+0x231/0x510 kernel/events/callchain.c:204
 perf_callchain kernel/events/core.c:7734 [inline]
 perf_sample_save_callchain include/linux/perf_event.h:1232 [inline]
 perf_prepare_sample+0x3c7/0x1db0 kernel/events/core.c:7778
 __perf_event_output kernel/events/core.c:7966 [inline]
 perf_event_output_forward+0x187/0x3e0 kernel/events/core.c:7987
 __perf_event_overflow+0x461/0x660 kernel/events/core.c:9712
 perf_swevent_overflow kernel/events/core.c:9795 [inline]
 perf_swevent_event+0x319/0x570 kernel/events/core.c:9846
 perf_tp_event+0x620/0x1550 kernel/events/core.c:10373
 perf_trace_run_bpf_submit+0xf4/0x1c0 kernel/events/core.c:10292
 perf_trace_preemptirq_template+0x269/0x330 include/trace/events/preemptirq.h:14
 trace_irq_disable+0xbb/0xe0 include/trace/events/preemptirq.h:36
 irqentry_enter+0x37/0x50 kernel/entry/common.c:381
 sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1088
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:kasan_quarantine_put+0x88/0x220 mm/kasan/quarantine.c:243
Code: e8 1d ef ad ff 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 0f 85 83 00 00 00 41 f7 c7 00 02 00 00 74 01 fb 31 c0 <48> 83 c4 08 5b 41 5c 41 5d 41 5e 41 5f c3 48 8d 80 40 7b 03 00 45
RSP: 0018:ffffc90000007aa0 EFLAGS: 00000206
RAX: b3194cbb81709301 RBX: ffff88803123f280 RCX: b3194cbb81709300
RDX: dffffc0000000000 RSI: ffffffff8acacb60 RDI: ffffffff8b1c7be0
RBP: ffff88803123f280 R08: ffffffff911bc52f R09: 1ffffffff22378a5
R10: dffffc0000000000 R11: fffffbfff22378a6 R12: 0000000000000000
R13: ffffc90000007b38 R14: 0000000000016900 R15: 0000000000000282
 kasan_slab_free include/linux/kasan.h:164 [inline]
 slab_free_hook mm/slub.c:1811 [inline]
 slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837
 slab_free mm/slub.c:3830 [inline]
 kmem_cache_free+0xf8/0x290 mm/slub.c:3852
 mac80211_hwsim_beacon_tx+0x3df/0x770 drivers/net/wireless/virtual/mac80211_hwsim.c:2269
 __iterate_interfaces+0x225/0x4c0 net/mac80211/util.c:766
 ieee80211_iterate_active_interfaces_atomic+0xdb/0x180 net/mac80211/util.c:802
 mac80211_hwsim_beacon+0xbb/0x1b0 drivers/net/wireless/virtual/mac80211_hwsim.c:2295
 __run_hrtimer kernel/time/hrtimer.c:1754 [inline]
 __hrtimer_run_queues+0x525/0xc10 kernel/time/hrtimer.c:1818
 hrtimer_run_softirq+0x177/0x290 kernel/time/hrtimer.c:1835
 handle_softirqs+0x27d/0x820 kernel/softirq.c:578
 __do_softirq kernel/softirq.c:612 [inline]
 invoke_softirq kernel/softirq.c:452 [inline]
 __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661
 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xc0/0x120 kernel/locking/spinlock.c:194
Code: c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 41 c6 04 07 f8 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 4b e4 ce f6 65 8b 05 1c 33 76 75 85 c0 74 3c 48 c7 04 24 0e 36
RSP: 0018:ffffc90003447560 EFLAGS: 00000206
RAX: dffffc0000000004 RBX: 0000000000000a06 RCX: b3194cbb81709300
RDX: dffffc0000000000 RSI: ffffffff8acacb60 RDI: 0000000000000001
RBP: ffffc900034475e0 R08: ffffffff911bc52f R09: 1ffffffff22378a5
R10: dffffc0000000000 R11: fffffbfff22378a6 R12: dffffc0000000000
R13: ffff8880780e0000 R14: ffffffff975089a0 R15: 1ffff92000688eac
 __debug_check_no_obj_freed lib/debugobjects.c:999 [inline]
 debug_check_no_obj_freed+0x47b/0x520 lib/debugobjects.c:1020
 free_pages_prepare mm/page_alloc.c:1188 [inline]
 free_unref_page_prepare+0x1ed/0x8f0 mm/page_alloc.c:2366
 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2459
 discard_slab mm/slub.c:2127 [inline]
 __unfreeze_partials+0x1cf/0x210 mm/slub.c:2667
 put_cpu_partial+0x17c/0x250 mm/slub.c:2743
 __slab_free+0x319/0x400 mm/slub.c:3700
 qlink_free mm/kasan/quarantine.c:166 [inline]
 qlist_free_all+0x75/0xd0 mm/kasan/quarantine.c:185
 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:306
 kasan_slab_alloc include/linux/kasan.h:188 [inline]
 slab_post_alloc_hook+0x6a/0x4d0 mm/slab.h:767
 slab_alloc_node mm/slub.c:3495 [inline]
 __kmem_cache_alloc_node+0x194/0x250 mm/slub.c:3534
 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098
 kmalloc include/linux/slab.h:600 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 task_numa_work+0x921/0x1350 kernel/sched/fair.c:3375
 task_work_run+0x1d4/0x260 kernel/task_work.c:245
 get_signal+0x11da/0x1390 kernel/signal.c:2679
 arch_do_signal_or_restart+0xc2/0x7b0 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f0f9819ce59
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:00007ffd3bfcb268 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: 0000000000000044 RBX: 00007f0f98415fa0 RCX: 00007f0f9819ce59
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000480
RBP: 00007f0f98232e6f R08: 000000000000000a R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0f98415fac R14: 00007f0f98415fa0 R15: 00007f0f98415fa0
 </TASK>

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/06/21 20:38 linux-6.6.y d1cfde2d5d15 43bfcdb0 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: task hung in del_device_store
2026/04/26 16:58 linux-6.6.y 9760bf04666d 9c2d0995 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: task hung in del_device_store
2026/01/14 20:26 linux-6.6.y c596736dadab d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan INFO: task hung in del_device_store
2025/11/21 16:29 linux-6.6.y 0a805b6ea8cd 280ea308 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: task hung in del_device_store
2025/11/21 00:13 linux-6.6.y 0a805b6ea8cd 2cc4c24a .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: task hung in del_device_store
2026/05/27 21:22 linux-6.6.y 0a40c6fbd105 8777bdc3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan INFO: task hung in del_device_store
* Struck through repros no longer work on HEAD.