INFO: task kworker/u4:5:5047 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/u4:5 state:D stack:26528 pid: 5047 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.0.15:5049 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:syz.0.15 state:D stack:24016 pid: 5049 ppid: 4804 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:ffffc9000318f6a0 EFLAGS: 00050202 RAX: ffffffff83da7d01 RBX: 0000000000000038 RCX: 0000000000000007 RDX: 0000000000000000 RSI: ffffc9000318f740 RDI: 00000000200003a0 RBP: 0000000000000000 R08: 0000000000000000 R09: fffff52000631eef R10: fffff52000631eef R11: 1ffff92000631ee8 R12: 00007ffffffff000 R13: 00000000200003d8 R14: ffffc9000318f740 R15: 00000000200003a0 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: 0033:0x7fc59bc73ed9 RSP: 002b:00007fc59aef2058 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fc59be39fa0 RCX: 00007fc59bc73ed9 RDX: 0000000020000380 RSI: 00000000c020660b RDI: 0000000000000004 RBP: 00007fc59bce7cc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc59be39fa0 R15: 00007ffc12fc2a68 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 3 locks held by kworker/0:3/1325: #0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc90005207d00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffffffff8c120de8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #2: ffffffff8c120de8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x347/0x6b0 kernel/rcu/tree_exp.h:845 2 locks held by getty/3947: #0: ffff88802c9c0098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc900025ce2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158 2 locks held by kworker/0:5/4296: #0: ffff888016872138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc90002fcfd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 2 locks held by kworker/u4:5/5047: #0: ffff88807573d138 ((wq_completion)btrfs-endio-write){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc9000321fd00 ((work_completion)(&work->normal_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 3 locks held by syz.0.15/5049: #0: ffff888020b44e28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #0: ffff888020b44e28 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2b9/0xc80 arch/x86/mm/fault.c:1298 #1: ffff88807d2cc558 (sb_pagefaults#2){.+.+}-{0:0}, at: do_page_mkwrite+0x168/0x3c0 mm/memory.c:2922 #2: ffff888069d18e68 (&ei->i_mmap_lock){.+.+}-{3:3}, at: btrfs_page_mkwrite+0x461/0xc50 fs/btrfs/inode.c:8965 1 lock held by udevd/5076: #0: ffff888020252118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820 2 locks held by syz.1.608/6289: #0: ffff888020252118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf9/0x7d0 block/bdev.c:915 #1: ffff888020726468 (&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 5.15.189-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: 4217 Comm: kworker/u4:4 Not tainted 5.15.189-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: phy9 ieee80211_iface_work RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:56 [inline] RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:347 [inline] RIP: 0010:deref_stack_reg+0x4f/0x120 arch/x86/kernel/unwind_orc.c:357 Code: c1 e8 03 42 80 3c 20 00 74 05 e8 3c 91 87 00 4d 8b 6f 08 49 8d 7f 10 48 89 f8 48 c1 e8 03 42 80 3c 20 00 74 05 e8 21 91 87 00 <49> 8b 6f 10 4c 89 f8 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 92 00 RSP: 0018:ffffc90002f4f370 EFLAGS: 00000246 RAX: 1ffff920005e9e8f RBX: ffffc90002f4f4a8 RCX: 0000000000000000 RDX: ffffc90002f4f4a8 RSI: ffffc90002f4f7d0 RDI: ffffc90002f4f478 RBP: ffffc90002f4f4b0 R08: dffffc0000000000 R09: ffffc90002f4f4b8 R10: fffff520005e9e99 R11: 1ffff920005e9e97 R12: dffffc0000000000 R13: ffffc90002f48000 R14: ffffc90002f4f7d0 R15: ffffc90002f4f468 FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8151191000 CR3: 000000002002b000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_next_frame+0x115d/0x1d90 arch/x86/kernel/unwind_orc.c:-1 arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc+0xb5/0xf0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:609 [inline] kzalloc include/linux/slab.h:735 [inline] ieee802_11_parse_elems_crc+0xab/0x10c0 net/mac80211/util.c:1478 ieee802_11_parse_elems net/mac80211/ieee80211_i.h:2243 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1609 [inline] ieee80211_ibss_rx_queued_mgmt+0x369/0x29c0 net/mac80211/ibss.c:1643 ieee80211_iface_process_skb net/mac80211/iface.c:1459 [inline] ieee80211_iface_work+0x70e/0xc60 net/mac80211/iface.c:1513 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