INFO: task syz-executor.0:6195 blocked for more than 143 seconds. Not tainted 6.12.0-rc6-syzkaller-00279-gde2f378f2b77 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:26448 pid:6195 tgid:6194 ppid:6126 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0xe55/0x5740 kernel/sched/core.c:6690 __schedule_loop kernel/sched/core.c:6767 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6782 schedule_timeout+0x258/0x2a0 kernel/time/timer.c:2591 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common+0x3e1/0x600 kernel/sched/completion.c:116 __flush_workqueue+0x39e/0x1200 kernel/workqueue.c:3973 nbd_start_device_ioctl drivers/block/nbd.c:1478 [inline] __nbd_ioctl drivers/block/nbd.c:1539 [inline] nbd_ioctl+0x308/0xfd0 drivers/block/nbd.c:1579 blkdev_ioctl+0x276/0x6d0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18f/0x220 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6f7ba7cda9 RSP: 002b:00007f6f7c8b00c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f6f7bbabf80 RCX: 00007f6f7ba7cda9 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003 RBP: 00007f6f7bac947a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f6f7bbabf80 R15: 00007ffffffed6f8 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e1b8340 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e1b8340 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e1b8340 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6720 2 locks held by kworker/u8:7/3478: 2 locks held by kworker/u9:1/5137: #0: ffff888026283148 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204 #1: ffffc9000ff57d80 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 2 locks held by getty/5578: #0: ffff888035de80a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211 1 lock held by syz-executor.0/11283: #0: ffff88802627f198 (&nbd->config_lock){+.+.}-{3:3}, at: nbd_ioctl+0x151/0xfd0 drivers/block/nbd.c:1572 1 lock held by syz-executor.0/11284: #0: ffff88802627f198 (&nbd->config_lock){+.+.}-{3:3}, at: nbd_ioctl+0x151/0xfd0 drivers/block/nbd.c:1572 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc6-syzkaller-00279-gde2f378f2b77 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xf0c/0x1240 kernel/hung_task.c:379 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 11 Comm: kworker/u8:0 Not tainted 6.12.0-rc6-syzkaller-00279-gde2f378f2b77 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 Workqueue: events_unbound cfg80211_wiphy_work RIP: 0010:__orc_find+0x8e/0xf0 arch/x86/kernel/unwind_orc.c:106 Code: 00 48 89 da 48 c1 ea 03 0f b6 34 0a 48 89 da 83 e2 07 83 c2 03 40 38 f2 7c 05 40 84 f6 75 4b 48 63 13 48 01 da 49 39 d5 73 af <4c> 8d 63 fc 49 39 ec 73 b2 4d 29 f7 49 c1 ff 02 4b 8d 14 7f 48 8d RSP: 0018:ffffc900001076b8 EFLAGS: 00000297 RAX: ffffffff90eb3dcc RBX: ffffffff906b9500 RCX: dffffc0000000000 RDX: ffffffff8100528a RSI: 0000000000000000 RDI: ffffffff906b94ac RBP: ffffffff906b9500 R08: ffffffff90eb3e6e R09: ffffffff90ef9766 R10: ffffc90000107768 R11: 0000000000000052 R12: ffffffff906b9504 R13: ffffffff81005289 R14: ffffffff906b94ac R15: ffffffff906b94fc FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2f4e44ed58 CR3: 000000000df7c000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: orc_find arch/x86/kernel/unwind_orc.c:227 [inline] unwind_next_frame+0x2be/0x20c0 arch/x86/kernel/unwind_orc.c:494 arch_stack_walk+0x95/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:2342 [inline] slab_free mm/slub.c:4579 [inline] kmem_cache_free+0x152/0x4b0 mm/slub.c:4681 skb_kfree_head net/core/skbuff.c:1084 [inline] skb_kfree_head net/core/skbuff.c:1081 [inline] skb_free_head+0x18a/0x1d0 net/core/skbuff.c:1098 skb_release_data+0x560/0x730 net/core/skbuff.c:1125 skb_release_all net/core/skbuff.c:1190 [inline] __kfree_skb net/core/skbuff.c:1204 [inline] sk_skb_reason_drop+0x129/0x1a0 net/core/skbuff.c:1242 kfree_skb_reason include/linux/skbuff.h:1262 [inline] kfree_skb include/linux/skbuff.h:1271 [inline] ieee80211_iface_work+0x437/0xf00 net/mac80211/iface.c:1659 cfg80211_wiphy_work+0x3d9/0x550 net/wireless/core.c:440 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244