INFO: task syz.8.2733:17640 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.8.2733 state:D stack:26552 pid:17640 tgid:17639 ppid:14535 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7058 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115 rwsem_down_read_slowpath+0x64e/0xbf0 kernel/locking/rwsem.c:1086 __down_read_common kernel/locking/rwsem.c:1261 [inline] __down_read kernel/locking/rwsem.c:1274 [inline] down_read+0xef/0x480 kernel/locking/rwsem.c:1539 __super_lock fs/super.c:59 [inline] super_lock+0x31c/0x3f0 fs/super.c:121 __iterate_supers+0x1e0/0x360 fs/super.c:923 quota_sync_all fs/quota/quota.c:69 [inline] __do_sys_quotactl fs/quota/quota.c:938 [inline] __se_sys_quotactl fs/quota/quota.c:917 [inline] __x64_sys_quotactl+0x2b3/0x440 fs/quota/quota.c:917 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff8c338ebe9 RSP: 002b:00007ff8c4154038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3 RAX: ffffffffffffffda RBX: 00007ff8c35c5fa0 RCX: 00007ff8c338ebe9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000100 RBP: 00007ff8c3411e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff8c35c6038 R14: 00007ff8c35c5fa0 R15: 00007ffdd84930a8 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e5c1260 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5c1260 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e5c1260 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775 2 locks held by getty/5605: #0: ffff88814d0f50a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5850: #0: ffff8880562940e0 (&type->s_umount_key#85){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff8880562940e0 (&type->s_umount_key#85){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff8880562940e0 (&type->s_umount_key#85){++++}-{4:4}, at: deactivate_super fs/super.c:506 [inline] #0: ffff8880562940e0 (&type->s_umount_key#85){++++}-{4:4}, at: deactivate_super+0xd6/0x100 fs/super.c:503 1 lock held by syz.8.2733/17640: #0: ffff8880562940e0 (&type->s_umount_key#85){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff8880562940e0 (&type->s_umount_key#85){++++}-{4:4}, at: super_lock+0x31c/0x3f0 fs/super.c:121 1 lock held by syz.3.3103/19379: #0: ffff8880562940e0 (&type->s_umount_key#85){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff8880562940e0 (&type->s_umount_key#85){++++}-{4:4}, at: super_lock+0x31c/0x3f0 fs/super.c:121 1 lock held by syz.9.3233/19908: #0: ffff8880562940e0 (&type->s_umount_key#85){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff8880562940e0 (&type->s_umount_key#85){++++}-{4:4}, at: super_lock+0x31c/0x3f0 fs/super.c:121 3 locks held by syz.6.3290/20123: 1 lock held by syz.2.3300/20154: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xf0e/0x1260 kernel/hung_task.c:491 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: 1c 62 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 53 13 16 00 fb f4 4c 09 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffc90000197df8 EFLAGS: 000002c2 RAX: 0000000002bfe007 RBX: 0000000000000001 RCX: ffffffff8b93fc29 RDX: 0000000000000000 RSI: ffffffff8de50a40 RDI: ffffffff8c162a00 RBP: ffffed1003c56488 R08: 0000000000000001 R09: ffffed10170a6655 R10: ffff8880b85332ab R11: 0000000000000000 R12: 0000000000000001 R13: ffff88801e2b2440 R14: ffffffff90ab5290 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881247b8000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000200030 CR3: 000000007459c000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:757 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x391/0x510 kernel/sched/idle.c:330 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428 start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x148