INFO: task syz.0.16:5060 blocked for more than 143 seconds. Not tainted 5.15.186-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.16 state:D stack:24016 pid: 5060 ppid: 4762 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376 schedule+0x11b/0x1e0 kernel/sched/core.c:6459 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:8961 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+0x1eca/0x43c0 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:ffffc9000311f6a0 EFLAGS: 00050202 RAX: ffffffff83db8d01 RBX: 0000000000000038 RCX: 0000000000000007 RDX: 0000000000000000 RSI: ffffc9000311f740 RDI: 00002000000003e0 RBP: 0000000000000000 R08: 0000000000000000 R09: fffff52000623eef R10: fffff52000623eef R11: 1ffff92000623ee8 R12: 00007ffffffff000 R13: 0000200000000418 R14: ffffc9000311f740 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:5460 [inline] extent_fiemap+0x10ff/0x14f0 fs/btrfs/extent_io.c:5686 btrfs_fiemap+0xc0/0x110 fs/btrfs/inode.c:8584 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: 0033:0x7f48af965169 RSP: 002b:00007f48aebd6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f48afb7dfa0 RCX: 00007f48af965169 RDX: 00002000000003c0 RSI: 00000000c020660b RDI: 0000000000000004 RBP: 00007f48af9e62a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f48afb7dfa0 R15: 00007fff65ff55e8 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c11bfa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 3 locks held by kworker/u4:3/688: #0: ffff8880b903a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475 #1: ffff8880b9027848 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x4d6/0x810 kernel/sched/psi.c:891 #2: ffff88801d9f4d40 (&wdev->mtx){+.+.}-{3:3}, at: sdata_lock net/mac80211/ieee80211_i.h:1036 [inline] #2: ffff88801d9f4d40 (&wdev->mtx){+.+.}-{3:3}, at: ieee80211_ibss_work+0xa0/0x10b0 net/mac80211/ibss.c:1685 1 lock held by udevd/3548: #0: ffff8880204b8518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820 2 locks held by getty/3935: #0: ffff88802c34d098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc900025be2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158 3 locks held by syz.0.16/5060: #0: ffff88801686b228 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #0: ffff88801686b228 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2b9/0xc80 arch/x86/mm/fault.c:1298 #1: ffff888077786558 (sb_pagefaults#2){.+.+}-{0:0}, at: do_page_mkwrite+0x168/0x3c0 mm/memory.c:2922 #2: ffff88805ca91838 (&ei->i_mmap_lock){.+.+}-{3:3}, at: btrfs_page_mkwrite+0x461/0xc50 fs/btrfs/inode.c:8950 2 locks held by syz.1.598/6280: #0: ffff8880204b8518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf9/0x7d0 block/bdev.c:915 #1: ffff88802052d468 (&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 5.15.186-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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: 6282 Comm: syz.1.599 Not tainted 5.15.186-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0033:0x7f3f06567c86 Code: f0 72 6e 48 63 cd 48 01 c1 49 39 4f 08 72 4c 8d 4d ff 85 ed 74 33 66 0f 1f 44 00 00 48 39 f0 72 1b 4d 8b 07 49 89 c1 49 29 f1 <47> 0f b6 0c 08 45 84 c9 74 08 45 88 0c 00 49 8b 47 10 48 83 c0 01 RSP: 002b:00007f3f059154a0 EFLAGS: 00000206 RAX: 000000000042a90d RBX: 00007f3f05915540 RCX: 0000000000000096 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 00007f3f059155e0 RBP: 0000000000000102 R08: 00007f3efd4f6000 R09: 000000000042a90c R10: 0000000000000000 R11: 00007f3f05915550 R12: 0000000000000001 R13: 00007f3f067413e0 R14: 0000000000000000 R15: 00007f3f059155e0 FS: 00007f3f059166c0 GS: 0000000000000000