INFO: task syz.2.189:7086 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.189 state:D stack:24376 pid:7086 tgid:7085 ppid:5598 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1681/0x54c0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7564 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1662 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1739 [inline] __rt_mutex_slowlock_locked+0x1f28/0x2550 kernel/locking/rtmutex.c:1779 __rwbase_read_lock+0xc3/0x180 kernel/locking/rwbase_rt.c:114 rwbase_read_lock kernel/locking/rwbase_rt.c:147 [inline] __down_read kernel/locking/rwsem.c:1496 [inline] down_read+0x132/0x200 kernel/locking/rwsem.c:1570 __super_lock fs/super.c:60 [inline] super_lock+0x2d6/0x3d0 fs/super.c:122 __iterate_supers+0x126/0x250 fs/super.c:926 quota_sync_all fs/quota/quota.c:69 [inline] __do_sys_quotactl fs/quota/quota.c:938 [inline] __se_sys_quotactl+0x3a7/0x9e0 fs/quota/quota.c:917 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7faeb358cdd9 RSP: 002b:00007faeb17de028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3 RAX: ffffffffffffffda RBX: 00007faeb3805fa0 RCX: 00007faeb358cdd9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000100 RBP: 00007faeb3622d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007faeb3806038 R14: 00007faeb3805fa0 R15: 00007ffce2312138 Showing all locks held in the system: 1 lock held by kauditd/37: 1 lock held by khungtaskd/38: #0: ffffffff8dfc8140 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8dfc8140 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8dfc8140 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:8/180: 2 locks held by udevd/4962: 2 locks held by getty/5353: #0: ffff88803701d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003cbe2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211 1 lock held by udevd/5802: 1 lock held by udevd/5853: 2 locks held by syz-executor/6141: 2 locks held by syz-executor/6563: 1 lock held by syz.2.189/7086: #0: ffff8880406960d0 (&type->s_umount_key#64){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff8880406960d0 (&type->s_umount_key#64){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 4 locks held by syz.3.450/8323: 1 lock held by syz.7.458/8337: 4 locks held by syz-executor/8338: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline] watchdog+0xfd3/0x1030 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 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: 8336 Comm: syz.8.455 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:98 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:115 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:140 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:172 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:191 [inline] RIP: 0010:kasan_check_range+0x97/0x2c0 mm/kasan/generic.c:200 Code: 00 fc ff df 4d 8d 34 19 4d 89 f4 4d 29 dc 49 83 fc 10 7f 29 4d 85 e4 0f 84 3d 01 00 00 4c 89 cb 48 f7 d3 4c 01 fb 41 80 3b 00 <0f> 85 9e 01 00 00 49 ff c3 48 ff c3 75 ee e9 1d 01 00 00 44 89 dd RSP: 0000:ffffc9000fda7eb0 EFLAGS: 00000046 RAX: 0000000000000001 RBX: ffffffffffffffff RCX: ffffffff81cca00c RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8f88e1f0 RBP: 0000000000000000 R08: ffffffff8f88e1f7 R09: 1ffffffff1f11c3e R10: dffffc0000000000 R11: fffffbfff1f11c3e R12: 0000000000000001 R13: 0000000000000000 R14: fffffbfff1f11c3f R15: 1ffffffff1f11c3e FS: 00007f3c85d266c0(0000) GS:ffff888126279000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3c7d97b000 CR3: 0000000035bf0000 CR4: 00000000003526f0 Call Trace: instrument_atomic_read include/linux/instrumented.h:82 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] cpumask_test_cpu include/linux/cpumask.h:649 [inline] cpu_online include/linux/cpumask.h:1231 [inline] trace_irq_disable+0x2c/0x140 include/trace/events/preemptirq.h:36 enter_from_user_mode include/linux/irq-entry-common.h:108 [inline] irqentry_enter_from_user_mode include/linux/irq-entry-common.h:301 [inline] irqentry_enter+0x7f/0x130 kernel/entry/common.c:113 exc_page_fault+0x26/0xc0 arch/x86/mm/fault.c:1524 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7f3c87983f0e Code: c1 49 39 4f 08 72 54 8d 4d ff 85 ed 74 3b 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 39 f0 72 1b 4d 8b 07 49 89 c1 49 29 f1 <47> 0f b6 0c 08 45 84 c9 74 08 45 88 0c 00 49 8b 47 10 48 83 c0 01 RSP: 002b:00007f3c85d25470 EFLAGS: 00010206 RAX: 0000000000075001 RBX: 00007f3c85d25530 RCX: 0000000000000093 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 00007f3c85d255d0 RBP: 0000000000000102 R08: 00007f3c7d906000 R09: 0000000000075000 R10: 0000000000000000 R11: 00007f3c85d25540 R12: 0000000000000001 R13: 00007f3c87b82900 R14: 0000000000000000 R15: 00007f3c85d255d0