INFO: task syz.2.13:6026 blocked for more than 143 seconds. Not tainted 6.15.0-rc6-syzkaller-00052-g9f35e33144ae #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.13 state:D stack:28808 pid:6026 tgid:6009 ppid:5832 task_flags:0x400040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x168f/0x4c70 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 rwsem_down_read_slowpath+0x552/0x880 kernel/locking/rwsem.c:1084 __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1526 inode_lock_shared include/linux/fs.h:877 [inline] lookup_slow+0x46/0x70 fs/namei.c:1833 walk_component fs/namei.c:2138 [inline] link_path_walk+0x925/0xe50 fs/namei.c:2503 path_lookupat+0x97/0x430 fs/namei.c:2659 filename_lookup+0x212/0x570 fs/namei.c:2689 user_path_at+0x3a/0x60 fs/namei.c:3120 do_mount fs/namespace.c:4218 [inline] __do_sys_mount fs/namespace.c:4432 [inline] __se_sys_mount+0x2d3/0x410 fs/namespace.c:4409 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f04f5b8e969 RSP: 002b:00007f04f6aab038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f04f5db6080 RCX: 00007f04f5b8e969 RDX: 0000000000000000 RSI: 0000200000000200 RDI: 0000200000000000 RBP: 00007f04f5c10ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000101091 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f04f5db6080 R15: 00007ffc00097e78 INFO: task syz.2.13:6030 blocked for more than 144 seconds. Not tainted 6.15.0-rc6-syzkaller-00052-g9f35e33144ae #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.13 state:D stack:28952 pid:6030 tgid:6009 ppid:5832 task_flags:0x400040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x168f/0x4c70 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 rwsem_down_read_slowpath+0x552/0x880 kernel/locking/rwsem.c:1084 __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1526 inode_lock_shared include/linux/fs.h:877 [inline] lookup_slow+0x46/0x70 fs/namei.c:1833 walk_component+0x2d2/0x400 fs/namei.c:2138 lookup_last fs/namei.c:2636 [inline] path_lookupat+0x163/0x430 fs/namei.c:2660 filename_lookup+0x212/0x570 fs/namei.c:2689 user_path_at+0x3a/0x60 fs/namei.c:3120 do_mount fs/namespace.c:4218 [inline] __do_sys_mount fs/namespace.c:4432 [inline] __se_sys_mount+0x2d3/0x410 fs/namespace.c:4409 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f04f5b8e969 RSP: 002b:00007f04f6a8a038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f04f5db6160 RCX: 00007f04f5b8e969 RDX: 0000000000000000 RSI: 00002000000005c0 RDI: 0000000000000000 RBP: 00007f04f5c10ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000100000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f04f5db6160 R15: 00007ffc00097e78 Showing all locks held in the system: 1 lock held by pool_workqueue_/3: 1 lock held by khungtaskd/31: #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 4 locks held by kworker/u8:8/3490: #0: ffff888143aa3148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff888143aa3148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc9000c037c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000c037c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffff88807f53c0e0 (&type->s_umount_key#63){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:562 #3: ffff8880580de730 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:102 2 locks held by getty/5588: #0: ffff8880326080a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002ffe2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 2 locks held by udevd/5932: 4 locks held by syz.2.13/6010: 1 lock held by syz.2.13/6026: #0: ffff8880580deae0 (&type->i_mutex_dir_key#9){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:877 [inline] #0: ffff8880580deae0 (&type->i_mutex_dir_key#9){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1833 1 lock held by syz.2.13/6030: #0: ffff8880580deae0 (&type->i_mutex_dir_key#9){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:877 [inline] #0: ffff8880580deae0 (&type->i_mutex_dir_key#9){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1833 2 locks held by syz.7.110/6871: #0: ffff88807f53c0e0 (&type->s_umount_key#63){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88807f53c0e0 (&type->s_umount_key#63){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 #1: ffff8880246aa7d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline] #1: ffff8880246aa7d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10 fs/fs-writeback.c:2831 2 locks held by syz.7.110/6872: #0: ffff88807f53c0e0 (&type->s_umount_key#63){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88807f53c0e0 (&type->s_umount_key#63){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 #1: ffff8880246aa7d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline] #1: ffff8880246aa7d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10 fs/fs-writeback.c:2831 6 locks held by dhcpcd-run-hook/7564: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc6-syzkaller-00052-g9f35e33144ae #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:437 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 13 Comm: kworker/u8:1 Not tainted 6.15.0-rc6-syzkaller-00052-g9f35e33144ae #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:lock_acquire+0x7/0x360 kernel/locking/lockdep.c:5826 Code: ff ff 00 0f 95 c0 e9 18 c9 b3 09 cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 57 <41> 56 41 55 41 54 53 48 83 ec 60 4d 89 ce 45 89 c7 41 89 cc 89 54 RSP: 0018:ffffc90000127aa0 EFLAGS: 00000246 RAX: 0000000000000001 RBX: ffff888032abc480 RCX: 0000000000000002 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8df3dce0 RBP: ffff88805e0b1ae0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff8b1d2e82 R12: dffffc0000000000 R13: ffffffff8b1d2e82 R14: ffff88805ed70d80 R15: 000000000000035c FS: 0000000000000000(0000) GS:ffff8881260fb000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffeacb022b8 CR3: 0000000033c86000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xef/0x610 net/batman-adv/network-coding.c:719 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245