INFO: task syz-executor.1:17505 blocked for more than 143 seconds. Not tainted 6.6.0-rc2-syzkaller-00018-g2cf0f7156238 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:27528 pid:17505 ppid:5079 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x196c/0x4af0 kernel/sched/core.c:6695 schedule+0xc3/0x180 kernel/sched/core.c:6771 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6830 rwsem_down_write_slowpath+0xee6/0x13a0 kernel/locking/rwsem.c:1178 __down_write_common+0x1aa/0x200 kernel/locking/rwsem.c:1306 inode_lock include/linux/fs.h:802 [inline] chmod_common+0x1bb/0x4c0 fs/open.c:637 vfs_fchmod fs/open.c:659 [inline] __do_sys_fchmod fs/open.c:668 [inline] __se_sys_fchmod fs/open.c:662 [inline] __x64_sys_fchmod+0xf3/0x160 fs/open.c:662 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f10be87cae9 RSP: 002b:00007f10bf5150c8 EFLAGS: 00000246 ORIG_RAX: 000000000000005b RAX: ffffffffffffffda RBX: 00007f10be99c050 RCX: 00007f10be87cae9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007f10be8c847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f10be99c050 R15: 00007ffebe447bc8 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8d32c4a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:303 [inline] #0: ffffffff8d32c4a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:749 [inline] #0: ffffffff8d32c4a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6613 5 locks held by kworker/u4:4/58: 2 locks held by getty/4790: #0: ffff88802010b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900015a72f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b1/0x1dc0 drivers/tty/n_tty.c:2206 2 locks held by syz-executor.1/17496: 2 locks held by syz-executor.1/17505: #0: ffff888017372410 (sb_writers#30){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:403 #1: ffff8880372e0168 (&type->i_mutex_dir_key#22){++++}-{3:3}, at: inode_lock include/linux/fs.h:802 [inline] #1: ffff8880372e0168 (&type->i_mutex_dir_key#22){++++}-{3:3}, at: chmod_common+0x1bb/0x4c0 fs/open.c:637 2 locks held by syz-executor.1/17733: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.6.0-rc2-syzkaller-00018-g2cf0f7156238 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023 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+0xfa9/0xff0 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:304 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 58 Comm: kworker/u4:4 Not tainted 6.6.0-rc2-syzkaller-00018-g2cf0f7156238 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023 Workqueue: bat_events batadv_nc_worker RIP: 0010:variable_test_bit arch/x86/include/asm/bitops.h:228 [inline] RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:240 [inline] RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline] RIP: 0010:hlock_class kernel/locking/lockdep.c:228 [inline] RIP: 0010:check_wait_context kernel/locking/lockdep.c:4772 [inline] RIP: 0010:__lock_acquire+0x58d/0x7f70 kernel/locking/lockdep.c:5086 Code: b6 04 00 84 c0 0f 85 13 15 00 00 44 89 3b 44 89 cb 48 89 d8 48 c1 e8 06 48 8d 3c c5 80 93 6f 90 be 08 00 00 00 e8 43 79 7b 00 <48> 0f a3 1d bb 97 02 0f 73 23 48 69 c3 d0 00 00 00 48 8d 98 80 f2 RSP: 0018:ffffc90001597720 EFLAGS: 00000056 RAX: 0000000000000001 RBX: 0000000000000020 RCX: ffffffff816cfbbd RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff906f9380 RBP: ffffc900015979e8 R08: ffffffff906f9387 R09: 1ffffffff20df270 R10: dffffc0000000000 R11: fffffbfff20df271 R12: ffff888018ee0000 R13: 0000000000000020 R14: 0000000000020020 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc4dee03440 CR3: 000000000d130000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5753 rcu_lock_acquire include/linux/rcupdate.h:303 [inline] rcu_read_lock include/linux/rcupdate.h:749 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xec/0x610 net/batman-adv/network-coding.c:719 process_one_work kernel/workqueue.c:2630 [inline] process_scheduled_works+0x90f/0x1400 kernel/workqueue.c:2703 worker_thread+0xa5f/0xff0 kernel/workqueue.c:2784 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:304