INFO: task syz.0.16:5075 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.16 state:D stack:23888 pid: 5075 ppid: 4810 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 wait_on_state fs/btrfs/extent_io.c:868 [inline] wait_extent_bit+0x39b/0x4d0 fs/btrfs/extent_io.c:906 lock_extent_bits+0x82/0x110 fs/btrfs/extent_io.c:1469 btrfs_page_mkwrite+0x5b1/0xc50 fs/btrfs/inode.c:8976 do_page_mkwrite+0x168/0x3c0 mm/memory.c:2922 wp_page_shared+0x16b/0x6d0 mm/memory.c:3259 handle_pte_fault mm/memory.c:4668 [inline] __handle_mm_fault mm/memory.c:4785 [inline] handle_mm_fault+0x1ec7/0x43b0 mm/memory.c:4883 do_user_addr_fault+0x489/0xc80 arch/x86/mm/fault.c:1357 handle_page_fault arch/x86/mm/fault.c:1445 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1501 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606 RIP: 0010:copy_user_generic_unrolled+0x89/0xc0 arch/x86/lib/copy_user_64.S:92 Code: 38 4c 89 47 20 4c 89 4f 28 4c 89 57 30 4c 89 5f 38 48 8d 76 40 48 8d 7f 40 ff c9 75 b6 89 d1 83 e2 07 c1 e9 03 74 12 4c 8b 06 <4c> 89 07 48 8d 76 08 48 8d 7f 08 ff c9 75 ee 21 d2 74 10 89 d1 8a RSP: 0018:ffffc9000323f6a0 EFLAGS: 00050202 RAX: ffffffff83daee01 RBX: 0000000000000038 RCX: 0000000000000007 RDX: 0000000000000000 RSI: ffffc9000323f740 RDI: 00002000000003e0 RBP: 0000000000000000 R08: 0000000000000000 R09: fffff52000647eef R10: fffff52000647eef R11: 1ffff92000647ee8 R12: 00007ffffffff000 R13: 0000200000000418 R14: ffffc9000323f740 R15: 00002000000003e0 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline] raw_copy_to_user arch/x86/include/asm/uaccess_64.h:58 [inline] _copy_to_user+0xf0/0x130 lib/usercopy.c:40 copy_to_user include/linux/uaccess.h:200 [inline] fiemap_fill_next_extent+0x19d/0x360 fs/ioctl.c:144 emit_fiemap_extent fs/btrfs/extent_io.c:5468 [inline] extent_fiemap+0x10ff/0x14f0 fs/btrfs/extent_io.c:5694 btrfs_fiemap+0xc0/0x110 fs/btrfs/inode.c:8599 ioctl_fiemap fs/ioctl.c:219 [inline] do_vfs_ioctl+0x1464/0x1de0 fs/ioctl.c:814 __do_sys_ioctl fs/ioctl.c:872 [inline] __se_sys_ioctl+0x83/0x170 fs/ioctl.c:860 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: 0033:0x7f613b246169 RSP: 002b:00007f613a4b7038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f613b45efa0 RCX: 00007f613b246169 RDX: 00002000000003c0 RSI: 00000000c020660b RDI: 0000000000000004 RBP: 00007f613b2c72a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f613b45efa0 R15: 00007fffbc6671f8 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c11c760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 1 lock held by klogd/3550: #0: ffff8880b913a358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475 1 lock held by udevd/3561: #0: ffff88802000a118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820 2 locks held by getty/3943: #0: ffff88802bbe4098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc900026562e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158 3 locks held by syz.0.16/5075: #0: ffff8880229fce28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #0: ffff8880229fce28 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2b9/0xc80 arch/x86/mm/fault.c:1298 #1: ffff88807b78e558 (sb_pagefaults#2){.+.+}-{0:0}, at: do_page_mkwrite+0x168/0x3c0 mm/memory.c:2922 #2: ffff88805d680e68 (&ei->i_mmap_lock){.+.+}-{3:3}, at: btrfs_page_mkwrite+0x461/0xc50 fs/btrfs/inode.c:8965 1 lock held by syz-executor/5099: #0: ffff8880b913a358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475 2 locks held by syz.1.578/6254: #0: ffff88802000a118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf9/0x7d0 block/bdev.c:915 #1: ffff8881475ac468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x4d/0x1f0 drivers/block/loop.c:2071 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 144 Comm: kworker/u4:1 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: phy11 ieee80211_iface_work RIP: 0010:hlock_class kernel/locking/lockdep.c:197 [inline] RIP: 0010:check_wait_context kernel/locking/lockdep.c:4686 [inline] RIP: 0010:__lock_acquire+0x523/0x7c60 kernel/locking/lockdep.c:4962 Code: 81 e3 ff 1f 00 00 41 c1 ed 03 41 81 e5 f8 03 00 00 49 8d bd c0 e0 fb 8f be 08 00 00 00 e8 85 31 60 00 48 0f a3 1d 7d dc 9f 0e <73> 1f 48 8d 04 5b c1 e0 06 48 8d 98 80 5f 94 8f 48 ba 00 00 00 00 RSP: 0018:ffffc900016ff8a0 EFLAGS: 00000057 RAX: 0000000000000001 RBX: 0000000000000a5a RCX: ffffffff815c043b RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8ffbe208 RBP: ffffc900016ffaf0 R08: dffffc0000000000 R09: fffffbfff1ff7c42 R10: fffffbfff1ff7c42 R11: 1ffffffff1ff7c41 R12: ffff88801ba028d0 R13: 0000000000000148 R14: 0000000000000000 R15: ffff88801ba028b0 FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055556612f608 CR3: 000000007e79f000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623 process_one_work+0x79f/0x1000 kernel/workqueue.c:2285 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