INFO: task syz.0.5251:30048 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.5251      state:D stack:25160 pid:30048 tgid:30047 ppid:29356  task_flags:0x400140 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7058
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
 __mutex_lock_common kernel/locking/mutex.c:676 [inline]
 __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760
 hfs_find_init+0x184/0x200 fs/hfs/bfind.c:-1
 hfs_ext_read_extent fs/hfs/extent.c:200 [inline]
 hfs_extend_file+0x2ee/0x1230 fs/hfs/extent.c:401
 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269
 __hfs_ext_write_extent+0x1fa/0x470 fs/hfs/extent.c:121
 __hfs_ext_cache_extent+0x6b/0x9b0 fs/hfs/extent.c:174
 hfs_ext_read_extent fs/hfs/extent.c:202 [inline]
 hfs_extend_file+0x316/0x1230 fs/hfs/extent.c:401
 hfs_get_block+0x3d7/0xbd0 fs/hfs/extent.c:353
 __block_write_begin_int+0x6b2/0x1900 fs/buffer.c:2145
 block_write_begin fs/buffer.c:2256 [inline]
 cont_write_begin+0x789/0xb50 fs/buffer.c:2594
 hfs_write_begin+0x66/0xb0 fs/hfs/inode.c:52
 cont_expand_zero fs/buffer.c:2522 [inline]
 cont_write_begin+0x2fa/0xb50 fs/buffer.c:2584
 hfs_write_begin+0x66/0xb0 fs/hfs/inode.c:52
 hfs_file_truncate+0x190/0x9c0 fs/hfs/extent.c:494
 hfs_inode_setattr+0x4a9/0x670 fs/hfs/inode.c:654
 notify_change+0xb33/0xe40 fs/attr.c:552
 do_truncate+0x1a4/0x220 fs/open.c:68
 do_ftruncate+0x489/0x540 fs/open.c:195
 do_sys_ftruncate fs/open.c:210 [inline]
 __do_sys_ftruncate fs/open.c:215 [inline]
 __se_sys_ftruncate fs/open.c:213 [inline]
 __x64_sys_ftruncate+0x92/0xf0 fs/open.c:213
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f411278ebe9
RSP: 002b:00007f411362f038 EFLAGS: 00000246 ORIG_RAX: 000000000000004d
RAX: ffffffffffffffda RBX: 00007f41129b5fa0 RCX: 00007f411278ebe9
RDX: 0000000000000000 RSI: 000000000100c17a RDI: 0000000000000006
RBP: 00007f4112811e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f41129b6038 R14: 00007f41129b5fa0 R15: 00007ffcce19dfa8
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
 watchdog+0xf60/0xfa0 kernel/hung_task.c:495
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x47c/0x820 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 15456 Comm: kworker/u8:37 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x0/0x90 kernel/kcov.c:313
Code: 7c 11 10 48 89 74 11 18 48 89 44 11 20 c3 cc cc cc cc cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 8b 04 24 65 48 8b 14 25 08 10 c2 92 65 8b 0d 08 7d
RSP: 0018:ffffc9000ad3f9f8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88802e171e00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: fffffffffffffe38 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff8b4c0730 R12: dffffc0000000000
R13: ffffffff8b4c0802 R14: ffff8880248a8d80 R15: 000000000000026e
FS:  0000000000000000(0000) GS:ffff8881259ff000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558daa0608 CR3: 0000000075928000 CR4: 00000000003526f0
DR0: 0000000002000000 DR1: 0000000000000003 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 rcu_read_unlock include/linux/rcupdate.h:869 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline]
 batadv_nc_worker+0x1ff/0x610 net/batman-adv/network-coding.c:719
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x47c/0x820 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>