INFO: task syz.3.7055:31928 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.7055 state:D stack:26864 pid:31928 tgid:31915 ppid:27581 task_flags:0x400040 flags:0x00080003 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 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083 rwsem_down_read_slowpath+0x5fd/0x8f0 kernel/locking/rwsem.c:1086 __down_read_common kernel/locking/rwsem.c:1261 [inline] __down_read kernel/locking/rwsem.c:1274 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1539 __super_lock fs/super.c:59 [inline] super_lock+0x2a9/0x3b0 fs/super.c:121 __iterate_supers+0x126/0x290 fs/super.c:922 quota_sync_all fs/quota/quota.c:69 [inline] __do_sys_quotactl fs/quota/quota.c:938 [inline] __se_sys_quotactl+0x353/0x950 fs/quota/quota.c:917 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: 0033:0x7efdfa98efc9 RSP: 002b:00007efdfb818038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3 RAX: ffffffffffffffda RBX: 00007efdfabe6270 RCX: 00007efdfa98efc9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000100 RBP: 00007efdfaa11f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007efdfabe6308 R14: 00007efdfabe6270 R15: 00007ffc8f5709c8 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df3d4e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3d4e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df3d4e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5586: #0: ffff88803348a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 2 locks held by syz-executor/5822: 2 locks held by kworker/u8:10/20267: #0: ffff8880203e8148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff8880203e8148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc90003fffba0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc90003fffba0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 1 lock held by syz.3.7055/31928: #0: ffff88802fd740e0 (&type->s_umount_key#68){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff88802fd740e0 (&type->s_umount_key#68){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121 1 lock held by syz.4.7258/430: 1 lock held by syz.1.7260/443: ============================================= 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 10/02/2025 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 32475 Comm: kworker/u8:4 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:arch_atomic64_read arch/x86/include/asm/atomic64_64.h:15 [inline] RIP: 0010:raw_atomic64_read include/linux/atomic/atomic-arch-fallback.h:2583 [inline] RIP: 0010:atomic64_read include/linux/atomic/atomic-instrumented.h:1611 [inline] RIP: 0010:switch_mm_irqs_off+0x3c5/0x7b0 arch/x86/mm/tlb.c:939 Code: a3 02 00 00 4c 89 f7 be 08 00 00 00 e8 34 51 b0 00 f0 4d 0f ab 27 4d 8d b5 58 07 00 00 4c 89 f7 be 08 00 00 00 e8 eb 50 b0 00 <4c> 89 f0 48 c1 e8 03 80 3c 18 00 74 08 4c 89 f7 e8 66 4e b0 00 4d RSP: 0018:ffffc9000459f3c0 EFLAGS: 00000056 RAX: 0000000000000001 RBX: dffffc0000000000 RCX: ffffffff81756d25 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff8880308b1cd8 RBP: ffffc9000459f490 R08: ffff8880308b1cdf R09: 1ffff1100611639b R10: dffffc0000000000 R11: ffffed100611639c R12: 0000000000000001 R13: ffff8880308b1580 R14: ffff8880308b1cd8 R15: ffff8880308b1f80 FS: 0000000000000000(0000) GS:ffff88812623e000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00002000003b0000 CR3: 000000000dd38000 CR4: 0000000000350ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: context_switch kernel/sched/core.c:5309 [inline] __schedule+0x110e/0x4cc0 kernel/sched/core.c:6929 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7113 preempt_schedule+0xae/0xc0 kernel/sched/core.c:7137 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 on_each_cpu_cond_mask+0x7a/0x80 kernel/smp.c:1044 on_each_cpu include/linux/smp.h:71 [inline] smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2713 [inline] smp_text_poke_batch_finish+0xe98/0x1130 arch/x86/kernel/alternative.c:3006 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x128/0x250 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xad/0x240 mm/kfence/core.c:852 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 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 vkms_vblank_simulate: vblank timer overrun