INFO: task syz-executor.3:6829 blocked for more than 143 seconds. Not tainted 6.8.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.3 state:D stack:26552 pid:6829 tgid:6826 ppid:5103 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5400 [inline] __schedule+0x177f/0x49a0 kernel/sched/core.c:6727 __schedule_loop kernel/sched/core.c:6802 [inline] schedule+0x149/0x260 kernel/sched/core.c:6817 request_wait_answer fs/fuse/dev.c:407 [inline] __fuse_request_send fs/fuse/dev.c:426 [inline] fuse_simple_request+0x1198/0x1b90 fs/fuse/dev.c:513 fuse_send_open fs/fuse/file.c:50 [inline] fuse_file_open+0x50d/0xb60 fs/fuse/file.c:147 fuse_do_open fs/fuse/file.c:174 [inline] fuse_open_common+0x302/0x680 fs/fuse/file.c:253 do_dentry_open+0x907/0x15a0 fs/open.c:953 do_open fs/namei.c:3645 [inline] path_openat+0x285f/0x3240 fs/namei.c:3802 do_filp_open+0x234/0x490 fs/namei.c:3829 do_sys_openat2+0x13e/0x1d0 fs/open.c:1404 do_sys_open fs/open.c:1419 [inline] __do_sys_openat fs/open.c:1435 [inline] __se_sys_openat fs/open.c:1430 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1430 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7fabdcc7c9a0 RSP: 002b:00007fabdd917e80 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000010000 RCX: 00007fabdcc7c9a0 RDX: 0000000000010000 RSI: 0000000020000080 RDI: 00000000ffffff9c RBP: 0000000020000080 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000020000080 R13: 00007fabdd917f40 R14: 0000000000000000 R15: 0000000020002100 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8e130be0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #0: ffffffff8e130be0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #0: ffffffff8e130be0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 2 locks held by kworker/u4:8/2794: 2 locks held by udevd/4509: #0: ffff8880278c02d0 (&type->i_mutex_dir_key#5){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:814 [inline] #0: ffff8880278c02d0 (&type->i_mutex_dir_key#5){++++}-{3:3}, at: lookup_slow+0x45/0x70 fs/namei.c:1709 #1: ffff8880b9428988 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x441/0x770 kernel/sched/psi.c:988 2 locks held by getty/4815: #0: ffff88802b7940a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b4/0x1e10 drivers/tty/n_tty.c:2201 1 lock held by syz-fuzzer/6116: 1 lock held by udevd/8710: 1 lock held by syz-executor.0/9898: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.8.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106 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:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xfaf/0xff0 kernel/hung_task.c:379 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:243 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 9898 Comm: syz-executor.0 Not tainted 6.8.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 RIP: 0010:io_serial_in+0x76/0xb0 drivers/tty/serial/8250/8250_port.c:410 Code: 40 5c 70 fc 89 e9 41 d3 e6 48 83 c3 40 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 b1 32 cf fc 44 03 33 44 89 f2 ec <0f> b6 c0 5b 41 5e 41 5f 5d c3 cc cc cc cc 89 e9 80 e1 07 38 c1 7c RSP: 0018:ffffc90009a7efd8 EFLAGS: 00000002 RAX: 1ffffffff28efa00 RBX: ffffffff9477d760 RCX: 0000000000000000 RDX: 00000000000003fd RSI: 000000000003c57c RDI: 000000000003c57d RBP: 0000000000000000 R08: ffffffff85231006 R09: 1ffff11003f78046 R10: dffffc0000000000 R11: ffffffff85230fc0 R12: dffffc0000000000 R13: 00000000000026f6 R14: 00000000000003fd R15: dffffc0000000000 FS: 00007f0d702806c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055555673e8f8 CR3: 0000000031edc000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial_in drivers/tty/serial/8250/8250.h:117 [inline] serial_lsr_in drivers/tty/serial/8250/8250.h:139 [inline] wait_for_lsr drivers/tty/serial/8250/8250_port.c:2081 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3366 [inline] serial8250_console_write+0x110d/0x1840 drivers/tty/serial/8250/8250_port.c:3444 console_emit_next_record kernel/printk/printk.c:2901 [inline] console_flush_all+0x808/0xec0 kernel/printk/printk.c:2967 console_unlock+0x13b/0x4d0 kernel/printk/printk.c:3036 vprintk_emit+0x508/0x720 kernel/printk/printk.c:2303 _printk+0xd5/0x120 kernel/printk/printk.c:2328 dump_stack_print_info+0xcc/0x150 lib/dump_stack.c:57 __dump_stack lib/dump_stack.c:87 [inline] dump_stack_lvl+0x1db/0x2e0 lib/dump_stack.c:106 fail_dump lib/fault-inject.c:52 [inline] should_fail_ex+0x3ae/0x4e0 lib/fault-inject.c:153 should_failslab+0x9/0x20 mm/slub.c:3747 slab_pre_alloc_hook mm/slub.c:3763 [inline] slab_alloc_node mm/slub.c:3842 [inline] __do_kmalloc_node mm/slub.c:3980 [inline] __kmalloc+0xe6/0x490 mm/slub.c:3994 kmalloc include/linux/slab.h:594 [inline] tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x2b7/0x740 security/tomoyo/file.c:822 security_inode_getattr+0xd8/0x130 security/security.c:2238 vfs_getattr+0x45/0x430 fs/stat.c:173 vfs_statx+0x1a5/0x4e0 fs/stat.c:248 do_statx fs/stat.c:681 [inline] __do_sys_statx fs/stat.c:708 [inline] __se_sys_statx fs/stat.c:699 [inline] __x64_sys_statx+0x1a4/0x240 fs/stat.c:699 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7f0d6f47dda9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f0d702800c8 EFLAGS: 00000246 ORIG_RAX: 000000000000014c RAX: ffffffffffffffda RBX: 00007f0d6f5abf80 RCX: 00007f0d6f47dda9 RDX: 0000000000000000 RSI: 0000000020000480 RDI: 0000000000000005 RBP: 00007f0d70280120 R08: 0000000020000800 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 R13: 000000000000000b R14: 00007f0d6f5abf80 R15: 00007ffd74d2d648