INFO: task kworker/u4:3:1196 blocked for more than 143 seconds. Not tainted 5.15.189-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:3 state:D stack:22016 pid: 1196 ppid: 2 flags:0x00004000 Workqueue: btrfs-endio-write btrfs_work_helper 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_finish_ordered_io+0x5dc/0x1b10 fs/btrfs/inode.c:3108 btrfs_work_helper+0x360/0xb90 fs/btrfs/async-thread.c:325 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 INFO: task syz.1.916:7443 blocked for more than 145 seconds. Not tainted 5.15.189-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.916 state:D stack:25888 pid: 7443 ppid: 4183 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 io_schedule+0x7c/0xd0 kernel/sched/core.c:8484 wait_on_page_bit_common+0x815/0xe00 mm/filemap.c:1356 lock_page include/linux/pagemap.h:625 [inline] btrfs_page_mkwrite+0x4f7/0xc50 fs/btrfs/inode.c:8966 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: 0033:0x7f84c008492b RSP: 002b:00007ffef0fd2228 EFLAGS: 00010202 RAX: 0000200000000940 RBX: 0000000000000004 RCX: 0000000000736f64 RDX: 0000000000000006 RSI: 000000006f64736d RDI: 0000200000000940 RBP: 00007f84c02e5da0 R08: 0000001b31120000 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000009 R12: 00007f84c02e3fac R13: 00007ffef0fd2320 R14: fffffffffffffffe R15: 00007ffef0fd2340 INFO: task syz.1.916:7444 blocked for more than 146 seconds. Not tainted 5.15.189-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.916 state:D stack:23968 pid: 7444 ppid: 4183 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: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+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:ffffc90005b4f6a0 EFLAGS: 00050202 RAX: ffffffff83da7d01 RBX: 0000000000000038 RCX: 0000000000000007 RDX: 0000000000000000 RSI: ffffc90005b4f740 RDI: 00002000000003a0 RBP: 0000000000000000 R08: 0000000000000000 R09: fffff52000b69eef R10: fffff52000b69eef R11: 1ffff92000b69ee8 R12: 00007ffffffff000 R13: 00002000000003d8 R14: ffffc90005b4f740 R15: 00002000000003a0 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: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: 0033:0x7f84c00bcbe9 RSP: 002b:00007f84be324038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f84c02e3fa0 RCX: 00007f84c00bcbe9 RDX: 0000200000000380 RSI: 00000000c020660b RDI: 0000000000000004 RBP: 00007f84c013fe19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f84c02e4038 R14: 00007f84c02e3fa0 R15: 00007ffef0fd20c8 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c11c360 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by kworker/0:2/1107: #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 locks held by kworker/u4:3/1196: #0: ffff88814c9fb138 ((wq_completion)btrfs-endio-write){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc90005057d00 ((work_completion)(&work->normal_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 2 locks held by getty/3948: #0: ffff88807e418098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc900025e62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158 2 locks held by syz-executor/4193: #0: ffff8880203fe118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf9/0x7d0 block/bdev.c:915 #1: ffff888147363468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0xaa/0xb90 drivers/block/loop.c:1366 4 locks held by kworker/0:18/7256: #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: ffff8880b9028098 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x123/0x270 kernel/time/timer.c:946 #3: ffff88801f8730e0 (&nsim_trap_data->trap_lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:363 [inline] #3: ffff88801f8730e0 (&nsim_trap_data->trap_lock){+.+.}-{2:2}, at: nsim_dev_trap_report drivers/net/netdevsim/dev.c:707 [inline] #3: ffff88801f8730e0 (&nsim_trap_data->trap_lock){+.+.}-{2:2}, at: nsim_dev_trap_report_work+0x1af/0xb40 drivers/net/netdevsim/dev.c:762 3 locks held by kworker/1:16/7431: #0: ffff88801bd69138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc90005897d00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffff888148179220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline] #2: ffff888148179220 (&dev->mutex){....}-{3:3}, at: hub_event+0x18f/0x4fa0 drivers/usb/core/hub.c:5781 3 locks held by syz.1.916/7443: #0: ffff88807e316328 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #0: ffff88807e316328 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2b9/0xc80 arch/x86/mm/fault.c:1298 #1: ffff88807d7d2558 (sb_pagefaults#3){.+.+}-{0:0}, at: do_page_mkwrite+0x168/0x3c0 mm/memory.c:2922 #2: ffff88805ff32208 (&ei->i_mmap_lock){.+.+}-{3:3}, at: btrfs_page_mkwrite+0x461/0xc50 fs/btrfs/inode.c:8965 3 locks held by syz.1.916/7444: #0: ffff88807e316328 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #0: ffff88807e316328 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2b9/0xc80 arch/x86/mm/fault.c:1298 #1: ffff88807d7d2558 (sb_pagefaults#3){.+.+}-{0:0}, at: do_page_mkwrite+0x168/0x3c0 mm/memory.c:2922 #2: ffff88805ff32208 (&ei->i_mmap_lock){.+.+}-{3:3}, at: btrfs_page_mkwrite+0x461/0xc50 fs/btrfs/inode.c:8965 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.189-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] NMI backtrace for cpu 0 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:728