INFO: task syz.0.24:5351 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.24 state:D stack:24784 pid: 5351 ppid: 5048 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 schedule_timeout+0xbd/0x2d0 kernel/time/timer.c:2093 do_wait_for_common+0x2a2/0x450 kernel/sched/completion.c:85 __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x48/0x60 kernel/sched/completion.c:138 kthread_stop+0x16e/0x540 kernel/kthread.c:666 gfs2_make_fs_ro+0x157/0x620 fs/gfs2/super.c:537 signal_our_withdraw fs/gfs2/util.c:166 [inline] gfs2_withdraw+0x610/0x1490 fs/gfs2/util.c:343 gfs2_metatype_check_ii+0x74/0x90 fs/gfs2/util.c:520 gfs2_metatype_check_i fs/gfs2/util.h:129 [inline] gfs2_quota_init+0xca5/0xea0 fs/gfs2/quota.c:1406 gfs2_make_fs_rw+0x414/0x580 fs/gfs2/super.c:159 gfs2_fill_super+0x1837/0x1f00 fs/gfs2/ops_fstype.c:1276 get_tree_bdev+0x3f1/0x610 fs/super.c:1325 gfs2_get_tree+0x4d/0x1e0 fs/gfs2/ops_fstype.c:1332 vfs_get_tree+0x88/0x270 fs/super.c:1530 do_new_mount+0x24a/0xa40 fs/namespace.c:3034 do_mount fs/namespace.c:3377 [inline] __do_sys_mount fs/namespace.c:3585 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562 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: 0033:0x7f09ebf77b8a RSP: 002b:00007f09eb1dce58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f09eb1dcee0 RCX: 00007f09ebf77b8a RDX: 0000200000000400 RSI: 0000200000012500 RDI: 00007f09eb1dcea0 RBP: 0000200000000400 R08: 00007f09eb1dcee0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000012500 R13: 00007f09eb1dcea0 R14: 00000000000125bb R15: 00002000000004c0 INFO: task gfs2_quotad:5360 blocked for more than 146 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:gfs2_quotad state:D stack:27096 pid: 5360 ppid: 2 flags:0x00004000 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 bit_wait+0xd/0xc0 kernel/sched/wait_bit.c:199 __wait_on_bit kernel/sched/wait_bit.c:49 [inline] out_of_line_wait_on_bit+0x173/0x230 kernel/sched/wait_bit.c:64 wait_on_bit include/linux/wait_bit.h:76 [inline] __gfs2_glock_dq+0x6b5/0xa10 fs/gfs2/glock.c:1588 gfs2_glock_dq fs/gfs2/glock.c:1652 [inline] gfs2_glock_dq_uninit+0x4f/0x110 fs/gfs2/glock.c:1672 gfs2_statfs_sync+0x718/0x7c0 fs/gfs2/super.c:314 quotad_check_timeo fs/gfs2/quota.c:1519 [inline] gfs2_quotad+0x372/0x890 fs/gfs2/quota.c:1581 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c31eb20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by kworker/u4:1/144: #0: ffff888016c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1 #1: ffff8880b9027888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x4fe/0x7d0 kernel/sched/psi.c:891 3 locks held by kworker/u4:2/154: 2 locks held by kworker/u4:4/1213: 2 locks held by getty/3949: #0: ffff88814d178098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158 1 lock held by syz-executor/5052: #0: ffff88802062d518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820 1 lock held by syz-executor/5062: #0: ffff888020634d18 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820 2 locks held by udevd/5067: #0: ffff888020634d18 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf9/0x7d0 block/bdev.c:915 #1: ffff88802095f468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0xaa/0xb90 drivers/block/loop.c:1366 2 locks held by udevd/5344: 2 locks held by udevd/5345: #0: ffff88802062f118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf9/0x7d0 block/bdev.c:915 #1: ffff88802095c468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0xaa/0xb90 drivers/block/loop.c:1366 1 lock held by syz.0.24/5351: #0: ffff8880605ee0e0 (&type->s_umount_key#53/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229 1 lock held by syz-executor/5454: #0: ffff888020638518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820 2 locks held by udevd/5544: #0: ffff88802062d518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf9/0x7d0 block/bdev.c:915 #1: ffff888020959468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0xaa/0xb90 drivers/block/loop.c:1366 1 lock held by syz.2.399/6496: #0: ffff88802062f118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820 3 locks held by syz.4.406/6518: 1 lock held by sed/6525: ============================================= NMI backtrace for cpu 1 CPU: 1 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 14 Comm: ksoftirqd/0 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:unwind_next_frame+0x3ce/0x1d90 arch/x86/kernel/unwind_orc.c:461 Code: b6 04 28 84 c0 0f 85 87 14 00 00 41 c6 06 01 48 c7 c2 a0 92 28 8a 4c 8d 72 04 4c 8d 7a 05 4d 89 f4 49 c1 ec 03 43 0f b6 04 2c <84> c0 48 89 14 24 0f 85 af 13 00 00 4c 89 f8 48 c1 e8 03 42 0f b6 RSP: 0018:ffffc90000d37548 EFLAGS: 00000a07 RAX: 0000000000000000 RBX: ffffc90000d37608 RCX: ffffffff8d993418 RDX: ffffffff8e054112 RSI: ffffffff8e054112 RDI: 0000000000000001 RBP: ffffffff81518985 R08: 0000000000000001 R09: 0000000000000008 R10: dffffc0000000000 R11: fffff520001a6ecd R12: 1ffffffff1c0a822 R13: dffffc0000000000 R14: ffffffff8e054116 R15: ffffffff8e054117 FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6c504be9e8 CR3: 0000000058638000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1710 [inline] slab_free_freelist_hook+0xea/0x170 mm/slub.c:1736 slab_free mm/slub.c:3504 [inline] kmem_cache_free+0x8f/0x210 mm/slub.c:3520 rcu_do_batch kernel/rcu/tree.c:2523 [inline] rcu_core+0x9d2/0x1670 kernel/rcu/tree.c:2763 handle_softirqs+0x339/0x830 kernel/softirq.c:576 run_ksoftirqd+0xa4/0x100 kernel/softirq.c:943 smpboot_thread_fn+0x4f6/0x970 kernel/smpboot.c:164 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287