INFO: task syz.0.17:4318 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.17 state:D stack:29088 pid: 4318 ppid: 4291 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 rwsem_down_write_slowpath+0xc46/0x11f0 kernel/locking/rwsem.c:1165 inode_lock include/linux/fs.h:787 [inline] ntfs_fallocate+0x1a9/0xcc0 fs/ntfs3/file.c:558 vfs_fallocate+0x587/0x6f0 fs/open.c:308 ksys_fallocate fs/open.c:331 [inline] __do_sys_fallocate fs/open.c:339 [inline] __se_sys_fallocate fs/open.c:337 [inline] __x64_sys_fallocate+0xbd/0x100 fs/open.c:337 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f97e5c90749 RSP: 002b:00007f97e52de038 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007f97e5ee7090 RCX: 00007f97e5c90749 RDX: 000000000000000a RSI: 0000000000000001 RDI: 0000000000000005 RBP: 00007f97e5d14f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000009 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f97e5ee7128 R14: 00007f97e5ee7090 R15: 00007ffd92b44718 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c11c720 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by getty/3951: #0: ffff88802bbae098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002d032e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158 4 locks held by syz.0.17/4317: 2 locks held by syz.0.17/4318: #0: ffff88807d874460 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3043 [inline] #0: ffff88807d874460 (sb_writers#13){.+.+}-{0:0}, at: vfs_fallocate+0x4f4/0x6f0 fs/open.c:307 #1: ffff888068717240 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff888068717240 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: ntfs_fallocate+0x1a9/0xcc0 fs/ntfs3/file.c:558 4 locks held by syz.1.18/4342: 2 locks held by syz.1.18/4343: #0: ffff88801a7c0460 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3043 [inline] #0: ffff88801a7c0460 (sb_writers#13){.+.+}-{0:0}, at: vfs_fallocate+0x4f4/0x6f0 fs/open.c:307 #1: ffff88805a046ae0 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff88805a046ae0 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: ntfs_fallocate+0x1a9/0xcc0 fs/ntfs3/file.c:558 3 locks held by syz.2.19/4373: 2 locks held by syz.2.19/4374: #0: ffff888022452460 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3043 [inline] #0: ffff888022452460 (sb_writers#13){.+.+}-{0:0}, at: vfs_fallocate+0x4f4/0x6f0 fs/open.c:307 #1: ffff8880684be380 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff8880684be380 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: ntfs_fallocate+0x1a9/0xcc0 fs/ntfs3/file.c:558 4 locks held by syz.3.20/4396: 2 locks held by syz.3.20/4397: #0: ffff8880740ac460 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3043 [inline] #0: ffff8880740ac460 (sb_writers#13){.+.+}-{0:0}, at: vfs_fallocate+0x4f4/0x6f0 fs/open.c:307 #1: ffff88806862f240 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff88806862f240 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: ntfs_fallocate+0x1a9/0xcc0 fs/ntfs3/file.c:558 3 locks held by syz.4.21/4425: 2 locks held by syz.4.21/4426: #0: ffff88805c360460 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3043 [inline] #0: ffff88805c360460 (sb_writers#13){.+.+}-{0:0}, at: vfs_fallocate+0x4f4/0x6f0 fs/open.c:307 #1: ffff8880703f6ae0 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff8880703f6ae0 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: ntfs_fallocate+0x1a9/0xcc0 fs/ntfs3/file.c:558 3 locks held by syz.5.22/4460: 2 locks held by syz.5.22/4461: #0: ffff888075a6c460 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3043 [inline] #0: ffff888075a6c460 (sb_writers#13){.+.+}-{0:0}, at: vfs_fallocate+0x4f4/0x6f0 fs/open.c:307 #1: ffff8880702e6380 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff8880702e6380 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: ntfs_fallocate+0x1a9/0xcc0 fs/ntfs3/file.c:558 4 locks held by syz.6.23/4489: 2 locks held by syz.6.23/4490: #0: ffff888060830460 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3043 [inline] #0: ffff888060830460 (sb_writers#13){.+.+}-{0:0}, at: vfs_fallocate+0x4f4/0x6f0 fs/open.c:307 #1: ffff8880702e0b00 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff8880702e0b00 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: ntfs_fallocate+0x1a9/0xcc0 fs/ntfs3/file.c:558 4 locks held by syz.7.24/4519: 2 locks held by syz.7.24/4520: #0: ffff888059828460 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3043 [inline] #0: ffff888059828460 (sb_writers#13){.+.+}-{0:0}, at: vfs_fallocate+0x4f4/0x6f0 fs/open.c:307 #1: ffff8880703f0b00 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff8880703f0b00 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: ntfs_fallocate+0x1a9/0xcc0 fs/ntfs3/file.c:558 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xe0f/0xe50 kernel/hung_task.c:369 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 154 Comm: kworker/u4:2 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:do_raw_spin_unlock+0x122/0x230 kernel/locking/spinlock_debug.c:142 Code: 00 74 0c 48 c7 c7 18 05 f9 8b e8 59 e3 5e 00 48 83 3d b9 b3 9b 0a 00 0f 84 10 01 00 00 48 89 df e8 33 de ff ff 66 90 5b 41 5c <41> 5d 41 5e 41 5f 5d c3 e8 c1 62 7a 02 85 c0 0f 84 05 ff ff ff 48 RSP: 0018:ffffc90001fd7b08 EFLAGS: 00000246 RAX: 0000000000000001 RBX: ffff888019f91b00 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff888019f91b00 RBP: 1ffff110033f2361 R08: dffffc0000000000 R09: ffffed10033f2361 R10: ffffed10033f2361 R11: 1ffff110033f2360 R12: ffff88807e7e3360 R13: 1ffff110033f2362 R14: ffff888019f91b10 R15: ffff888019f91b08 FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055c0457bda38 CR3: 000000005a8c4000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:175 [inline] _raw_spin_unlock_bh+0x1f/0x30 kernel/locking/spinlock.c:210 spin_unlock_bh include/linux/spinlock.h:409 [inline] batadv_nc_purge_paths+0x316/0x3b0 net/batman-adv/network-coding.c:475 batadv_nc_worker+0x327/0x5c0 net/batman-adv/network-coding.c:726 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287