INFO: task syz-executor.0:5602 blocked for more than 143 seconds. Not tainted 6.6.0-syzkaller-14142-g90b0c2b2edd1 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:28400 pid:5602 tgid:5600 ppid:5416 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5376 [inline] __schedule+0xee2/0x59a0 kernel/sched/core.c:6688 __schedule_loop kernel/sched/core.c:6763 [inline] schedule+0xe7/0x270 kernel/sched/core.c:6778 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6835 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x969/0x1340 kernel/locking/mutex.c:747 blkdev_put+0xb0/0x8e0 block/bdev.c:928 bdev_release+0x4f/0x80 block/bdev.c:952 blkdev_release+0x37/0x50 block/fops.c:616 __fput+0x270/0xbb0 fs/file_table.c:394 task_work_run+0x14d/0x240 kernel/task_work.c:180 get_signal+0x106f/0x2790 kernel/signal.c:2680 arch_do_signal_or_restart+0x90/0x7f0 arch/x86/kernel/signal.c:309 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x60 kernel/entry/common.c:296 do_syscall_64+0x4b/0x110 arch/x86/entry/common.c:88 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7fd657c7ad79 RSP: 002b:00007fd6573fe0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: 0000000000000000 RBX: 00007fd657d9bf80 RCX: 00007fd657c7ad79 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003 RBP: 00007fd657cd7797 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fd657d9bf80 R15: 00007ffdab839bb8 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8cfad260 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:301 [inline] #0: ffffffff8cfad260 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline] #0: ffffffff8cfad260 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6613 2 locks held by getty/4821: #0: ffff88802a3720a0 (&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+0xfc6/0x1490 drivers/tty/n_tty.c:2201 1 lock held by udevd/5411: #0: ffff8881407ef4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev.part.0+0x4f0/0xb20 block/bdev.c:786 1 lock held by syz-executor.0/5602: #0: ffff8881407ef4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xb0/0x8e0 block/bdev.c:928 1 lock held by syz-executor.0/5797: #0: ffff8881407ef4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev.part.0+0x4f0/0xb20 block/bdev.c:786 1 lock held by syz-executor.0/5813: #0: ffff8881407ef4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev.part.0+0x4f0/0xb20 block/bdev.c:786 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.6.0-syzkaller-14142-g90b0c2b2edd1 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x277/0x380 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x299/0x300 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+0xf87/0x1210 kernel/hung_task.c:379 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 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: 4509 Comm: klogd Not tainted 6.6.0-syzkaller-14142-g90b0c2b2edd1 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023 RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x8/0x20 kernel/kcov.c:290 Code: 00 00 f3 0f 1e fa 48 8b 0c 24 48 89 f2 48 89 fe bf 06 00 00 00 e9 08 ff ff ff 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 48 8b 0c 24 <40> 0f b6 d6 40 0f b6 f7 bf 01 00 00 00 e9 e6 fe ff ff 66 0f 1f 44 RSP: 0018:ffffc9000317f4a0 EFLAGS: 00000246 RAX: 0000000000000001 RBX: ffffc9000317f528 RCX: ffffffff813ab0d4 RDX: ffff88807b770000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffc9000317fce0 R13: 0000000000000001 R14: 0000000000000001 R15: 0000000000000001 FS: 00007f8857002380(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f06d340a6c0 CR3: 0000000028a65000 CR4: 0000000000350ef0 Call Trace: deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline] unwind_next_frame+0x1aa4/0x2390 arch/x86/kernel/unwind_orc.c:648 arch_stack_walk+0xfa/0x170 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x96/0xd0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 __kasan_slab_alloc+0x81/0x90 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook mm/slab.h:763 [inline] slab_alloc_node mm/slub.c:3478 [inline] kmem_cache_alloc_node+0x180/0x3c0 mm/slub.c:3523 __alloc_skb+0x287/0x330 net/core/skbuff.c:641 alloc_skb include/linux/skbuff.h:1286 [inline] alloc_skb_with_frags+0xe4/0x710 net/core/skbuff.c:6331 sock_alloc_send_pskb+0x7e4/0x970 net/core/sock.c:2780 unix_dgram_sendmsg+0x464/0x1ca0 net/unix/af_unix.c:1976 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0xd5/0x180 net/socket.c:745 __sys_sendto+0x255/0x340 net/socket.c:2194 __do_sys_sendto net/socket.c:2206 [inline] __se_sys_sendto net/socket.c:2202 [inline] __x64_sys_sendto+0xe0/0x1b0 net/socket.c:2202 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7f88571649b5 Code: 8b 44 24 08 48 83 c4 28 48 98 c3 48 98 c3 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 26 45 31 c9 45 31 c0 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 7a 48 8b 15 44 c4 0c 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffde66aeaf8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f88571649b5 RDX: 000000000000004e RSI: 000055fcf5ecc5d0 RDI: 0000000000000003 RBP: 000055fcf5ec7910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000004000 R11: 0000000000000246 R12: 0000000000000013 R13: 00007f88572f2212 R14: 00007ffde66aebf8 R15: 0000000000000000