INFO: task syz-executor.0:5605 blocked for more than 143 seconds. Not tainted 6.12.0-rc4-next-20241028-syzkaller-gdec9255a128e #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:26744 pid:5605 tgid:5604 ppid:5538 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5327 [inline] __schedule+0x184f/0x4c30 kernel/sched/core.c:6707 __schedule_loop kernel/sched/core.c:6784 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6799 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6856 __mutex_lock_common kernel/locking/mutex.c:665 [inline] __mutex_lock+0x7e7/0xee0 kernel/locking/mutex.c:735 bdev_release+0x17e/0x700 block/bdev.c:1087 blkdev_release+0x15/0x20 block/fops.c:635 __fput+0x23c/0xa50 fs/file_table.c:434 task_work_run+0x24f/0x310 kernel/task_work.c:239 get_signal+0x15e8/0x1740 kernel/signal.c:2690 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa16b87c859 RSP: 002b:00007fa16c5520c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: 0000000000000000 RBX: 00007fa16b99bf80 RCX: 00007fa16b87c859 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003 RBP: 00007fa16b8d8ad0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fa16b99bf80 R15: 00007ffe1630a478 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e939ee0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e939ee0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e939ee0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744 2 locks held by getty/4997: #0: ffff88814c7600a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 1 lock held by udevd/5540: #0: ffff8880257f44c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:904 1 lock held by syz-executor.0/5605: #0: ffff8880257f44c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x17e/0x700 block/bdev.c:1087 1 lock held by syz-executor.0/5915: #0: ffff8880257f44c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:904 1 lock held by syz-executor.0/5933: #0: ffff8880257f44c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:904 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc4-next-20241028-syzkaller-gdec9255a128e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 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+0xff4/0x1040 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/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: 62 Comm: kworker/u8:4 Not tainted 6.12.0-rc4-next-20241028-syzkaller-gdec9255a128e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:__lock_acquire+0x6c2/0x2100 kernel/locking/lockdep.c:5176 Code: 38 40 84 ed 4c 8b 6c 24 40 0f 84 7e 04 00 00 0f b6 1b 41 0f b6 04 16 84 c0 0f 85 64 12 00 00 41 f6 47 01 80 0f 85 63 04 00 00 <4c> 89 64 24 48 84 db 40 0f b6 c5 0f b6 cb 0f 44 c8 89 4c 24 6c 48 RSP: 0018:ffffc900015d7890 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff81705ab7 RDX: dffffc0000000000 RSI: ffff88801cf946e0 RDI: ffffffff942c4840 RBP: 0000000000000003 R08: ffffffff942c4847 R09: 1ffffffff2858908 R10: dffffc0000000000 R11: fffffbfff2858909 R12: ffff88801cf946c4 R13: ffff88801cf93c00 R14: 1ffff110039f28ea R15: ffff88801cf94750 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055682d9a6600 CR3: 000000000e736000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] batadv_nc_process_nc_paths+0xd6/0x3a0 net/batman-adv/network-coding.c:687 batadv_nc_worker+0x42a/0x610 net/batman-adv/network-coding.c:728 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244