INFO: task syz-executor:5860 blocked for more than 144 seconds.
Not tainted 6.17.0-rc1-next-20250814-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21608 pid:5860 tgid:5860 ppid:1 task_flags:0x400140 flags:0x00004004
Call Trace:
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
wb_wait_for_completion+0x15f/0x260 fs/fs-writeback.c:216
__writeback_inodes_sb_nr+0x1f6/0x250 fs/fs-writeback.c:2748
sync_filesystem+0xa3/0x230 fs/sync.c:54
generic_shutdown_super+0x6f/0x2c0 fs/super.c:622
bch2_kill_sb+0x41/0x50 fs/bcachefs/fs.c:2576
deactivate_locked_super+0xbc/0x130 fs/super.c:474
cleanup_mnt+0x425/0x4c0 fs/namespace.c:1378
task_work_run+0x1d4/0x260 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:43
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f39fc38ff17
RSP: 002b:00007ffcb0677948 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f39fc411c05 RCX: 00007f39fc38ff17
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffcb0677a00
RBP: 00007ffcb0677a00 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffcb0678a90
R13: 00007f39fc411c05 R14: 000000000001ffc0 R15: 00007ffcb0678ad0
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.17.0-rc1-next-20250814-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
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+0x3f9/0x770 arch/x86/kernel/process.c:148
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: 10209 Comm: syz.8.861 Not tainted 6.17.0-rc1-next-20250814-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:section_to_usemap include/linux/mmzone.h:1944 [inline]
RIP: 0010:get_pageblock_bitmap mm/page_alloc.c:340 [inline]
RIP: 0010:get_pfnblock_bitmap_bitidx mm/page_alloc.c:376 [inline]
RIP: 0010:__get_pfnblock_flags_mask+0x1af/0x240 mm/page_alloc.c:401
Code: 41 83 e4 7f 41 c1 e4 05 4d 01 e7 eb 03 45 31 ff 49 83 c7 08 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 01 04 0e 00 <49> 8b 07 45 89 f7 41 c1 ef 06 41 83 e7 38 41 c1 ee 09 41 83 e6 38
RSP: 0018:ffffc900048e6ed8 EFLAGS: 00000046
RAX: 1ffff11027fff4a5 RBX: 0000000000000017 RCX: dffffc0000000000
RDX: 0000000000000017 RSI: 000000000004b699 RDI: ffffea00012da640
RBP: 0000000000000780 R08: ffffea00012da677 R09: 1ffffd400025b4ce
R10: dffffc0000000000 R11: fffff9400025b4cf R12: 0000000000000120
R13: dffffc0000000000 R14: 000000000004b699 R15: ffff88813fffa528
FS: 0000000000000000(0000) GS:ffff888125c0f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbeeac03f98 CR3: 000000000df36000 CR4: 00000000003526f0
Call Trace:
get_pfnblock_migratetype mm/page_alloc.c:449 [inline]
__del_page_from_free_list+0x70/0x510 mm/page_alloc.c:861
__free_one_page+0x3c7/0xbd0 mm/page_alloc.c:995
free_pcppages_bulk+0x2da/0x4e0 mm/page_alloc.c:1488
free_frozen_page_commit+0x62c/0x1070 mm/page_alloc.c:2869
free_unref_folios+0x120b/0x1520 mm/page_alloc.c:3023
folios_put_refs+0x559/0x640 mm/swap.c:997
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x49e/0x14b0 mm/shmem.c:1157
shmem_truncate_range mm/shmem.c:1269 [inline]
shmem_evict_inode+0x272/0xa70 mm/shmem.c:1397
evict+0x501/0x9c0 fs/inode.c:810
__dentry_kill+0x209/0x660 fs/dcache.c:669
dput+0x19f/0x2b0 fs/dcache.c:911
__fput+0x68e/0xa70 fs/file_table.c:476
task_work_run+0x1d4/0x260 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x6b5/0x2300 kernel/exit.c:961
do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
get_signal+0x1286/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbee9d8ebe9
Code: Unable to access opcode bytes at 0x7fbee9d8ebbf.
RSP: 002b:00007fbeeac04038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: 0000000000010106 RBX: 00007fbee9fb6090 RCX: 00007fbee9d8ebe9
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000005
RBP: 00007fbee9e11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fbee9fb6128 R14: 00007fbee9fb6090 R15: 00007ffec5730b88