INFO: task syz-executor.0:3239 blocked for more than 143 seconds. Not tainted 6.7.0-rc5-syzkaller-00047-g5bd7ef53ffe5 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:26704 pid:3239 tgid:3238 ppid:5087 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5376 [inline] __schedule+0x1961/0x4ab0 kernel/sched/core.c:6688 __schedule_loop kernel/sched/core.c:6763 [inline] schedule+0x149/0x260 kernel/sched/core.c:6778 schedule_timeout+0xb0/0x300 kernel/time/timer.c:2143 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion+0x354/0x620 kernel/sched/completion.c:148 __flush_workqueue+0x730/0x1630 kernel/workqueue.c:3192 nbd_start_device_ioctl drivers/block/nbd.c:1450 [inline] __nbd_ioctl drivers/block/nbd.c:1511 [inline] nbd_ioctl+0xbcd/0xf40 drivers/block/nbd.c:1551 blkdev_ioctl+0x5cf/0x730 block/ioctl.c:633 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xf8/0x170 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x45/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7fa76107cba9 RSP: 002b:00007fa761d3f0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fa76119bf80 RCX: 00007fa76107cba9 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003 RBP: 00007fa7610c847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fa76119bf80 R15: 00007ffed9dab198 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8d92e060 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:301 [inline] #0: ffffffff8d92e060 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline] #0: ffffffff8d92e060 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 2 locks held by getty/4812: #0: ffff88801b9e80a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000312b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b4/0x1e10 drivers/tty/n_tty.c:2201 2 locks held by kworker/u5:7/5108: #0: ffff88801c9a8d38 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2602 [inline] #0: ffff88801c9a8d38 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2700 #1: ffffc90004757d20 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2602 [inline] #1: ffffc90004757d20 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2700 1 lock held by kworker/u4:0/28460: 1 lock held by syz-executor.1/27789: #0: ffffffff8d933900 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x550 kernel/rcu/tree.c:4030 1 lock held by syz-executor.0/28014: #0: ffff88801cb70198 (&nbd->config_lock){+.+.}-{3:3}, at: nbd_ioctl+0x13c/0xf40 drivers/block/nbd.c:1544 1 lock held by syz-executor.0/28018: #0: ffff88801cb70198 (&nbd->config_lock){+.+.}-{3:3}, at: nbd_ioctl+0x13c/0xf40 drivers/block/nbd.c:1544 1 lock held by syz-executor.4/28228: #0: ffff888140728198 (&nbd->config_lock){+.+.}-{3:3}, at: nbd_ioctl+0x13c/0xf40 drivers/block/nbd.c:1544 1 lock held by syz-executor.4/28229: #0: ffff888140728198 (&nbd->config_lock){+.+.}-{3:3}, at: nbd_ioctl+0x13c/0xf40 drivers/block/nbd.c:1544 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.7.0-rc5-syzkaller-00047-g5bd7ef53ffe5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x498/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x310 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+0xfaf/0xff0 kernel/hung_task.c:379 kthread+0x2d3/0x370 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3311 Comm: syz-executor.0 Not tainted 6.7.0-rc5-syzkaller-00047-g5bd7ef53ffe5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 RIP: 0010:check_region_inline mm/kasan/generic.c:172 [inline] RIP: 0010:kasan_check_range+0x17/0x290 mm/kasan/generic.c:187 Code: ff 48 89 df 48 c7 c6 c8 9e 12 8d e8 83 0a e7 ff 90 0f 0b 66 0f 1f 00 55 41 57 41 56 41 54 53 b0 01 48 85 f6 0f 84 a0 01 00 00 <4c> 8d 04 37 49 39 f8 0f 82 52 02 00 00 48 89 fd 48 c1 ed 2f 81 fd RSP: 0018:ffffc9000c7afab0 EFLAGS: 00000002 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff816d4e60 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8f00d2e8 RBP: ffffc9000c7afc10 R08: 0000000000000003 R09: fffff520018f5f74 R10: dffffc0000000000 R11: fffff520018f5f74 R12: 1ffff920018f5f68 R13: ffffffff848b438e R14: ffffc9000c7afc40 R15: dffffc0000000000 FS: 0000555556e46480(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f395237b1f8 CR3: 0000000017317000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read include/linux/instrumented.h:68 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] cpumask_test_cpu include/linux/cpumask.h:504 [inline] cpu_online include/linux/cpumask.h:1104 [inline] trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0xb0/0x9c0 kernel/locking/lockdep.c:5765 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline] _raw_spin_unlock_irqrestore+0x79/0x140 kernel/locking/spinlock.c:194 __debug_check_no_obj_freed lib/debugobjects.c:1042 [inline] debug_check_no_obj_freed+0x39e/0x420 lib/debugobjects.c:1063 slab_free_hook mm/slub.c:1775 [inline] slab_free_freelist_hook mm/slub.c:1826 [inline] slab_free mm/slub.c:3809 [inline] kmem_cache_free+0x249/0x470 mm/slub.c:3831 __dentry_kill+0x4f4/0x660 fs/dcache.c:621 dentry_kill+0xbb/0x290 dput+0x21e/0x470 fs/dcache.c:913 __fput+0x60b/0xa10 fs/file_table.c:402 __do_sys_close fs/open.c:1590 [inline] __se_sys_close fs/open.c:1575 [inline] __x64_sys_close+0x7e/0x100 fs/open.c:1575 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x45/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7f395227ba9a Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 03 7f 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 63 7f 02 00 8b 44 24 RSP: 002b:00007ffc3b2ba2d0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f395227ba9a RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007ffc3b2ba34c R08: 00000000000002d8 R09: 0079746972756365 R10: 00007f395237b860 R11: 0000000000000293 R12: 0000000000000032 R13: 000000000016b3ce R14: 000000000016b07b R15: 000000000000000f