INFO: task syz.0.543:7896 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.543 state:D stack:27344 pid:7896 tgid:7893 ppid:5630 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5504 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7228 __schedule_loop kernel/sched/core.c:7307 [inline] schedule+0x164/0x360 kernel/sched/core.c:7322 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7379 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821 bdev_open+0xde/0xd70 block/bdev.c:953 blkdev_open+0x461/0x600 block/fops.c:697 do_dentry_open+0x816/0x1380 fs/open.c:947 vfs_open+0x3b/0x340 fs/open.c:1079 do_open fs/namei.c:4700 [inline] path_openat+0x2e44/0x3830 fs/namei.c:4859 do_file_open+0x23e/0x4a0 fs/namei.c:4888 do_sys_openat2+0x115/0x200 fs/open.c:1395 do_sys_open fs/open.c:1401 [inline] __do_sys_openat fs/open.c:1417 [inline] __se_sys_openat fs/open.c:1412 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1412 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f85a1d5d68e RSP: 002b:00007f85a2cdfb28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f85a2ce06c0 RCX: 00007f85a1d5d68e RDX: 0000000000000000 RSI: 00007f85a2cdfc00 RDI: ffffffffffffff9c RBP: 00007f85a2cdfc00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd R13: 00007f85a2016038 R14: 00007f85a2015fa0 R15: 00007ffcd4dfe3b8 INFO: lockdep is turned off. NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline] watchdog+0xfd7/0x1030 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 10629 Comm: syz.4.1250 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:kasan_check_range+0xe/0x2c0 mm/kasan/generic.c:199 Code: e8 07 dd f6 fe 90 0f 0b cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 55 41 57 41 56 41 55 41 54 53 01 48 85 f6 0f 84 ae 01 00 00 4c 8d 04 37 49 39 f8 0f 82 36 02 RSP: 0018:ffffc9000c25ed60 EFLAGS: 00000246 RAX: ffffffff83f83abc RBX: 0000000000000010 RCX: ffffffff83e8f629 RDX: 0000000000000000 RSI: 0000000000000010 RDI: ffff88802b3bc000 RBP: ffffc9000c25ef50 R08: ffff888037f7d80f R09: 1ffff11006fefb01 R10: dffffc0000000000 R11: ffffed1006fefb02 R12: ffffffff83e8f629 R13: 0000000000000009 R14: ffff88802b3bc000 R15: ffff888058b42040 FS: 00007f9f577866c0(0000) GS:ffff8881252aa000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000001000 CR3: 000000006b1e1000 CR4: 0000000000350ef0 Call Trace: __asan_memcpy+0x29/0x70 mm/kasan/shadow.c:105 write_extent_buffer_chunk_tree_uuid fs/btrfs/extent_io.h:344 [inline] btrfs_init_new_buffer fs/btrfs/extent-tree.c:5307 [inline] btrfs_alloc_tree_block+0x779/0x12a0 fs/btrfs/extent-tree.c:5373 btrfs_force_cow_block+0x566/0x23a0 fs/btrfs/ctree.c:504 btrfs_cow_block+0x3f2/0xb20 fs/btrfs/ctree.c:699 btrfs_search_slot+0xd06/0x2d00 fs/btrfs/ctree.c:2112 btrfs_insert_empty_items+0xa3/0x1a0 fs/btrfs/ctree.c:4301 btrfs_insert_empty_item fs/btrfs/ctree.h:674 [inline] insert_with_overflow+0x104/0x380 fs/btrfs/dir-item.c:35 btrfs_insert_dir_item+0x207/0x5d0 fs/btrfs/dir-item.c:134 create_pending_snapshot+0xe7e/0x3690 fs/btrfs/transaction.c:1886 create_pending_snapshots+0x17c/0x1c0 fs/btrfs/transaction.c:1964 btrfs_commit_transaction+0xf5e/0x3020 fs/btrfs/transaction.c:2462 create_snapshot fs/btrfs/ioctl.c:785 [inline] btrfs_mksubvol+0x9c6/0x10a0 fs/btrfs/ioctl.c:863 btrfs_mksnapshot+0xa3/0xe0 fs/btrfs/ioctl.c:905 __btrfs_ioctl_snap_create+0x45d/0x6b0 fs/btrfs/ioctl.c:1169 btrfs_ioctl_snap_create_v2+0x1f1/0x3b0 fs/btrfs/ioctl.c:1248 btrfs_ioctl+0x8d0/0xd10 fs/btrfs/ioctl.c:-1 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9f5699ce59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f9f57786028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f9f56c16090 RCX: 00007f9f5699ce59 RDX: 0000200000000280 RSI: 0000000050009417 RDI: 0000000000000005 RBP: 00007f9f56a32d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f9f56c16128 R14: 00007f9f56c16090 R15: 00007ffd75073e48