INFO: task syz-executor409:5090 blocked for more than 143 seconds. Not tainted 6.10.0-rc1-syzkaller-00027-g4a4be1ad3a6e #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor409 state:D stack:26000 pid:5090 tgid:5089 ppid:5086 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6837 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x5b8/0x9c0 kernel/locking/mutex.c:752 bdev_release+0x166/0x6f0 block/bdev.c:1080 blkdev_release+0x15/0x20 block/fops.c:623 __fput+0x408/0xbb0 fs/file_table.c:422 task_work_run+0x14e/0x250 kernel/task_work.c:180 ptrace_notify+0x10e/0x130 kernel/signal.c:2402 ptrace_report_syscall include/linux/ptrace.h:415 [inline] ptrace_report_syscall_exit include/linux/ptrace.h:477 [inline] syscall_exit_work kernel/entry/common.c:173 [inline] syscall_exit_to_user_mode_prepare+0x126/0x260 kernel/entry/common.c:200 __syscall_exit_to_user_mode_work kernel/entry/common.c:205 [inline] syscall_exit_to_user_mode+0x11/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fdcdd2451a9 RSP: 002b:00007fdcdd1f5218 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: 0000000000000000 RBX: 00007fdcdd2c5328 RCX: 00007fdcdd2451a9 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003 RBP: 00007fdcdd2c5320 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fdcdd2c532c R13: 00007fdcdd2923b4 R14: 64626e2f7665642f R15: 00000000ffffff00 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8dbb18e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #0: ffffffff8dbb18e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #0: ffffffff8dbb18e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6614 6 locks held by kworker/u8:8/2800: 2 locks held by getty/4840: #0: ffff88802ad970a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc8/0x1490 drivers/tty/n_tty.c:2201 1 lock held by udevd/5087: #0: ffff8880205464c8 (&disk->open_mutex){+.+.}-{3:3}, at: bdev_open+0x41a/0xe50 block/bdev.c:897 1 lock held by syz-executor409/5090: #0: ffff8880205464c8 (&disk->open_mutex){+.+.}-{3:3}, at: bdev_release+0x166/0x6f0 block/bdev.c:1080 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 30 Comm: khungtaskd Not tainted 6.10.0-rc1-syzkaller-00027-g4a4be1ad3a6e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 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+0xf86/0x1240 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4526 Comm: klogd Not tainted 6.10.0-rc1-syzkaller-00027-g4a4be1ad3a6e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 RIP: 0010:import_ubuf+0x0/0x200 lib/iov_iter.c:1352 Code: 00 31 d2 50 31 f6 48 c7 c7 e0 18 bb 8d e8 48 b7 ea fc 58 c3 cc cc cc cc 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 41 57 41 56 41 55 49 89 f5 41 54 41 89 fc 55 48 89 d5 RSP: 0018:ffffc90003aafd00 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00005650700458b0 RCX: ffffc90003aafd78 RDX: 000000000000008b RSI: 00005650700458b0 RDI: 0000000000000001 RBP: 1ffff92000755fa3 R08: 0000000000000000 R09: 0000000000000000 R10: 1ffff92000755ff9 R11: 0000000000000000 R12: 0000000000000003 R13: 0000000000000000 R14: ffffc90003aafd68 R15: ffffc90003aafdf8 FS: 00007f68fd3aa380(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055f52d8a9600 CR3: 000000002d45e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __sys_sendto+0xe0/0x4e0 net/socket.c:2169 __do_sys_sendto net/socket.c:2204 [inline] __se_sys_sendto net/socket.c:2200 [inline] __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2200 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: 0033:0x7f68fd50c9b5 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:00007ffe882fb4a8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f68fd50c9b5 RDX: 000000000000008b RSI: 00005650700458b0 RDI: 0000000000000003 RBP: 000056507003f2c0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000004000 R11: 0000000000000246 R12: 0000000000000013 R13: 00007f68fd69a212 R14: 00007ffe882fb5a8 R15: 0000000000000000