INFO: task syz.8.1346:12624 blocked for more than 143 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.8.1346 state:D stack:25480 pid:12624 tgid:12621 ppid:9394 task_flags:0x400140 flags:0x00004006
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
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x7e6/0x1360 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+0xb36/0xe40 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/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f149498ebe9
RSP: 002b:00007f1495731038 EFLAGS: 00000246 ORIG_RAX: 000000000000004d
RAX: ffffffffffffffda RBX: 00007f1494bb5fa0 RCX: 00007f149498ebe9
RDX: 0000000000000000 RSI: 000000000100c17a RDI: 0000000000000005
RBP: 00007f1494a11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1494bb6038 R14: 00007f1494bb5fa0 R15: 00007ffc51c74628
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: 15471 Comm: syz.0.1951 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:preempt_count arch/x86/include/asm/preempt.h:27 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:246 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x11/0x90 kernel/kcov.c:321
Code: 09 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 0c 25 08 10 a1 92 <65> 8b 15 28 65 e1 10 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75
RSP: 0018:ffffc90004827438 EFLAGS: 00000246
RAX: ffffffff8200642b RBX: 0000000000000000 RCX: ffff88802b035a00
RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90004827570 R08: ffffea000132ea07 R09: 1ffffd4000265d40
R10: dffffc0000000000 R11: fffff94000265d41 R12: ffffc900048274c0
R13: dffffc0000000000 R14: 00000000000004b9 R15: ffffea000132ea00
FS: 00007f7d810396c0(0000) GS:ffff888125c0f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f340869ef98 CR3: 0000000070d4a000 CR4: 00000000003526f0
DR0: fffffffffffffff8 DR1: 0000000000000006 DR2: 0200000000000000
DR3: 0000000000000005 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
const_folio_flags include/linux/page-flags.h:351 [inline]
folio_test_swapbacked include/linux/page-flags.h:578 [inline]
shmem_add_to_page_cache+0x60b/0xba0 mm/shmem.c:912
shmem_alloc_and_add_folio+0x846/0xf60 mm/shmem.c:1973
shmem_get_folio_gfp+0x59d/0x1660 mm/shmem.c:2597
shmem_fault+0x179/0x390 mm/shmem.c:2798
__do_fault+0x135/0x390 mm/memory.c:5280
do_read_fault mm/memory.c:5701 [inline]
do_fault mm/memory.c:5835 [inline]
do_pte_missing mm/memory.c:4362 [inline]
handle_pte_fault mm/memory.c:6180 [inline]
__handle_mm_fault+0x3611/0x5440 mm/memory.c:6323
handle_mm_fault+0x40a/0x8e0 mm/memory.c:6492
faultin_page mm/gup.c:1144 [inline]
__get_user_pages+0x1699/0x2ce0 mm/gup.c:1446
populate_vma_page_range+0x29f/0x3a0 mm/gup.c:1880
__mm_populate+0x24c/0x380 mm/gup.c:1983
mm_populate include/linux/mm.h:3386 [inline]
vm_mmap_pgoff+0x387/0x4d0 mm/util.c:585
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7d8018ebe9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7d81039038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f7d803b5fa0 RCX: 00007f7d8018ebe9
RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007f7d80211e19 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7d803b6038 R14: 00007f7d803b5fa0 R15: 00007ffc4b7d6808