INFO: task kworker/u4:4:4229 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:4 state:D stack:22712 pid: 4229 ppid: 2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:5) Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537 __mutex_lock_common+0xcfc/0x2400 kernel/locking/mutex.c:669 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743 hfs_find_init+0x15b/0x1d0 fs/hfs/bfind.c:-1 hfs_ext_write_extent+0x14e/0x200 fs/hfs/extent.c:141 hfs_write_inode+0xd8/0xa20 fs/hfs/inode.c:432 write_inode fs/fs-writeback.c:1505 [inline] __writeback_single_inode+0x6c3/0xda0 fs/fs-writeback.c:1715 writeback_sb_inodes+0xa4e/0x1680 fs/fs-writeback.c:1940 __writeback_inodes_wb+0x12a/0x3f0 fs/fs-writeback.c:2011 wb_writeback+0x46f/0xbe0 fs/fs-writeback.c:2116 wb_check_background_flush fs/fs-writeback.c:2182 [inline] wb_do_writeback fs/fs-writeback.c:2270 [inline] wb_workfn+0xbd6/0xf20 fs/fs-writeback.c:2298 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310 worker_thread+0xaa6/0x1290 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.5.643:8276 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.643 state:D stack:27472 pid: 8276 ppid: 7783 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 rwsem_down_write_slowpath+0xc87/0x1260 kernel/locking/rwsem.c:1165 inode_lock include/linux/fs.h:787 [inline] hfs_file_release+0xb9/0x100 fs/hfs/inode.c:587 __fput+0x234/0x930 fs/file_table.c:311 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fb2ac226dd9 RSP: 002b:00007fff6718f948 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007fb2ac4a1da0 RCX: 00007fb2ac226dd9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007fb2ac4a1da0 R08: 0000000000000006 R09: 0000000000000000 R10: 00007fb2ac4a1cb0 R11: 0000000000000246 R12: 0000000000037e2a R13: 00007fb2ac4a018c R14: 0000000000037c59 R15: 00007fff6718fa50 INFO: task syz.5.643:8278 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.643 state:D stack:23472 pid: 8278 ppid: 7783 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537 __mutex_lock_common+0xcfc/0x2400 kernel/locking/mutex.c:669 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743 hfs_find_init+0x15b/0x1d0 fs/hfs/bfind.c:-1 hfs_ext_read_extent fs/hfs/extent.c:200 [inline] hfs_extend_file+0x35d/0x13f0 fs/hfs/extent.c:401 hfs_bmap_reserve+0x103/0x420 fs/hfs/btree.c:231 __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+0x39c/0x13f0 fs/hfs/extent.c:401 hfs_get_block+0x40f/0xc50 fs/hfs/extent.c:353 __block_write_begin_int+0x565/0x15d0 fs/buffer.c:2012 __block_write_begin fs/buffer.c:2062 [inline] block_write_begin fs/buffer.c:2122 [inline] cont_write_begin+0x598/0x7b0 fs/buffer.c:2471 hfs_write_begin+0x92/0xe0 fs/hfs/inode.c:59 cont_expand_zero fs/buffer.c:2398 [inline] cont_write_begin+0x263/0x7b0 fs/buffer.c:2461 hfs_write_begin+0x92/0xe0 fs/hfs/inode.c:59 hfs_file_truncate+0x1c2/0xa10 fs/hfs/extent.c:494 hfs_inode_setattr+0x4ab/0x6f0 fs/hfs/inode.c:657 notify_change+0xbcd/0xee0 fs/attr.c:505 do_truncate+0x1ac/0x240 fs/open.c:65 vfs_truncate+0x262/0x2f0 fs/open.c:111 do_sys_truncate+0xf2/0x1c0 fs/open.c:134 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: 0033:0x7fb2ac226dd9 RSP: 002b:00007fb2aa480028 EFLAGS: 00000246 ORIG_RAX: 000000000000004c RAX: ffffffffffffffda RBX: 00007fb2ac49ffa0 RCX: 00007fb2ac226dd9 RDX: 0000000000000000 RSI: 0000000002fffffd RDI: 0000200000000940 RBP: 00007fb2ac2bcd69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb2ac4a0038 R14: 00007fb2ac49ffa0 R15: 00007fff6718f7e8 INFO: lockdep is turned off. NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a2/0x3d0 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: 15286 Comm: dhcpcd-run-hook Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:__sanitizer_cov_trace_cmp8+0x7a/0x80 kernel/kcov.c:274 Code: c1 e0 05 4d 8d 50 28 4d 39 ca 77 1e 4a c7 44 02 08 06 00 00 00 4a 89 7c 02 10 4a 89 74 02 18 4a 89 44 02 20 48 ff c1 48 89 0a 0f 1f 44 00 00 48 8b 04 24 65 48 8b 0d c4 38 89 7e 65 8b 15 c5 RSP: 0018:ffffc90002e8fa88 EFLAGS: 00000293 RAX: ffffffff81afd1a8 RBX: 00007f5283998000 RCX: ffff8880252f9dc0 RDX: 0000000000000000 RSI: 00007f5283998000 RDI: 00007f5283a1e000 RBP: 0000299f66824000 R08: ffff88802b951c7b R09: 1ffff1100572a38f R10: dffffc0000000000 R11: ffffed100572a390 R12: ffff888018396860 R13: dffffc0000000000 R14: 00007f5283a1e000 R15: ffff888018396840 FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5283a4f420 CR3: 0000000054193000 CR4: 00000000003506e0 DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000002 DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: browse_rb mm/mmap.c:346 [inline] validate_mm+0x2a8/0x950 mm/mmap.c:423 remove_vma_list mm/mmap.c:2631 [inline] __do_munmap+0xcf3/0xdf0 mm/mmap.c:2902 do_munmap mm/mmap.c:2910 [inline] munmap_vma_range mm/mmap.c:603 [inline] __mmap_region mm/mmap.c:1757 [inline] mmap_region+0x8b4/0x1650 mm/mmap.c:2933 do_mmap+0x819/0xe90 mm/mmap.c:1586 vm_mmap_pgoff+0x1c1/0x2d0 mm/util.c:551 ksys_mmap_pgoff+0x54b/0x790 mm/mmap.c:1635 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: 0033:0x7f5283a6e242 Code: 08 00 04 00 00 eb e2 90 41 f7 c1 ff 0f 00 00 75 27 55 89 cd 53 48 89 fb 48 85 ff 74 33 41 89 ea 48 89 df b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 5e 5b 5d c3 0f 1f 00 c7 05 46 40 01 00 16 00 RSP: 002b:00007ffeaf407038 EFLAGS: 00000206 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f5283998000 RCX: 00007f5283a6e242 RDX: 0000000000000005 RSI: 0000000000086000 RDI: 00007f5283998000 RBP: 0000000000000812 R08: 0000000000000003 R09: 0000000000010000 R10: 0000000000000812 R11: 0000000000000206 R12: 00007ffeaf407088 R13: 00007f5283a4a0c0 R14: 00007ffeaf407440 R15: 00000fffd5e80e0a