INFO: task syz.0.17:6520 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17 state:D stack:26376 pid:6520 tgid:6520 ppid:6439 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7026
io_schedule+0x80/0xd0 kernel/sched/core.c:7871
folio_wait_bit_common+0x6b0/0xb80 mm/filemap.c:1330
folio_lock include/linux/pagemap.h:1141 [inline]
writeback_get_folio mm/page-writeback.c:2468 [inline]
writeback_iter+0x8d8/0x12a0 mm/page-writeback.c:2562
iomap_writepages+0x14d/0x2d0 fs/iomap/buffered-io.c:1769
gfs2_writepages+0x177/0x250 fs/gfs2/aops.c:175
do_writepages+0x32e/0x550 mm/page-writeback.c:2604
filemap_fdatawrite_wbc mm/filemap.c:389 [inline]
__filemap_fdatawrite_range mm/filemap.c:422 [inline]
__filemap_fdatawrite mm/filemap.c:428 [inline]
filemap_fdatawrite+0x199/0x240 mm/filemap.c:433
gfs2_ordered_write fs/gfs2/log.c:733 [inline]
gfs2_log_flush+0x966/0x24c0 fs/gfs2/log.c:1102
gfs2_trans_end+0x37c/0x570 fs/gfs2/trans.c:158
gfs2_page_mkwrite+0x14a8/0x1910 fs/gfs2/file.c:535
do_page_mkwrite+0x14d/0x310 mm/memory.c:3488
do_shared_fault mm/memory.c:5774 [inline]
do_fault mm/memory.c:5836 [inline]
do_pte_missing mm/memory.c:4361 [inline]
handle_pte_fault mm/memory.c:6177 [inline]
__handle_mm_fault+0x1916/0x5400 mm/memory.c:6318
handle_mm_fault+0x40a/0x8e0 mm/memory.c:6487
do_user_addr_fault+0xa7c/0x1380 arch/x86/mm/fault.c:1336
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x82/0x100 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7fbe046550b3
RSP: 002b:00007ffee1c0ddd0 EFLAGS: 00010246
RAX: 0000200000000180 RBX: 0000000000000008 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000555563a5a3c8
RBP: 00007ffee1c0ded8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 00007fbe049b5fac
R13: 00007fbe049b5fa0 R14: fffffffffffffffe R15: 00007ffee1c0df20
Showing all locks held in the system:
1 lock held by ksoftirqd/1/23:
1 lock held by khungtaskd/31:
#0: ffffffff8dd3d2e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8dd3d2e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8dd3d2e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:8/3506:
#0: ffff8880206a6148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
#0: ffff8880206a6148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1: ffffc9000c287ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
#1: ffffc9000c287ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
#2: ffff88802e1c20e0 (&type->s_umount_key#53){.+.+}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:562
#3: ffff88807ebcce50 (&sdp->sd_log_flush_lock){++++}-{4:4}, at: gfs2_log_flush+0x103/0x24c0 fs/gfs2/log.c:1045
2 locks held by getty/5602:
#0: ffff888033d370a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
4 locks held by syz.0.17/6520:
#0: ffff88807f1f6d08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1a3/0x450 mm/mmap_lock.c:238
#1: ffff88802e1c2518 (sb_pagefaults#2){.+.+}-{0:0}, at: do_page_mkwrite+0x14d/0x310 mm/memory.c:3488
#2: ffff88802e1c2610 (sb_internal#2){.+.+}-{0:0}, at: gfs2_trans_begin+0x6f/0xe0 fs/gfs2/trans.c:118
#3: ffff88807ebcce50 (&sdp->sd_log_flush_lock){++++}-{4:4}, at: gfs2_log_flush+0x103/0x24c0 fs/gfs2/log.c:1045
1 lock held by gfs2_logd/syz:s/6524:
#0: ffff88807ebcce50 (&sdp->sd_log_flush_lock){++++}-{4:4}, at: gfs2_log_flush+0x103/0x24c0 fs/gfs2/log.c:1045
2 locks held by syz.1.209/7324:
=============================================
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 08/18/2025
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+0x4bc/0x870 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: 7324 Comm: syz.1.209 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:245 [inline]
RIP: 0010:__sanitizer_cov_trace_cmp8+0x8/0x90 kernel/kcov.c:294
Code: 48 89 44 11 20 e9 18 30 7d 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 40 4b 92 65 8b 15 78 9b 8b 10 81 e2 00 01 ff 00
RSP: 0018:ffffc9000b527360 EFLAGS: 00000293
RAX: ffffffff823059f7 RBX: 0000000000000000 RCX: ffff888031a15ac0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001
RBP: 0000000000000001 R08: ffff88801d61d26f R09: 1ffff11003ac3a4d
R10: dffffc0000000000 R11: ffffed1003ac3a4e R12: ffff88801d61d270
R13: 0000000000000001 R14: 0000000000066c3b R15: 0000000000066c3b
FS: 00007f0f79e236c0(0000) GS:ffff88812616c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0f70fff000 CR3: 000000002d2a4000 CR4: 00000000003526f0
Call Trace:
__page_table_check_zero+0x1f7/0x530 mm/page_table_check.c:139
page_table_check_free include/linux/page_table_check.h:43 [inline]
free_pages_prepare mm/page_alloc.c:1395 [inline]
free_unref_folios+0xdc7/0x14f0 mm/page_alloc.c:2963
folios_put_refs+0x584/0x670 mm/swap.c:1002
free_pages_and_swap_cache+0x277/0x520 mm/swap_state.c:355
__tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline]
tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
tlb_flush_mmu_free mm/mmu_gather.c:397 [inline]
tlb_flush_mmu+0x3a0/0x680 mm/mmu_gather.c:404
tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497
vms_clear_ptes+0x42c/0x540 mm/vma.c:1235
vms_complete_munmap_vmas+0x206/0x8a0 mm/vma.c:1277
do_vmi_align_munmap+0x364/0x440 mm/vma.c:1536
do_vmi_munmap+0x253/0x2e0 mm/vma.c:1584
__vm_munmap+0x207/0x380 mm/vma.c:3156
__do_sys_munmap mm/mmap.c:1080 [inline]
__se_sys_munmap mm/mmap.c:1077 [inline]
__x64_sys_munmap+0x60/0x70 mm/mmap.c:1077
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: 0033:0x7f0f78f8ec77
Code: 00 00 00 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 0b 00 00 00 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:00007f0f79e22e18 EFLAGS: 00000246 ORIG_RAX: 000000000000000b
RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007f0f78f8ec77
RDX: 0000000000000000 RSI: 0000000008400000 RDI: 00007f0f70000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 000000000001f78a
R10: 000020000005e5c2 R11: 0000000000000246 R12: 0000000000000003
R13: 00007f0f79e22ef0 R14: 00007f0f79e22eb0 R15: 00007f0f70000000