INFO: task syz.1.2122:10675 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.2122 state:D stack:26128 pid:10675 ppid:4273 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 schedule+0xb9/0x180 kernel/sched/core.c:6638 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6697 rwsem_down_read_slowpath+0x516/0x870 kernel/locking/rwsem.c:1094 __down_read_common kernel/locking/rwsem.c:1261 [inline] __down_read kernel/locking/rwsem.c:1274 [inline] down_read+0x94/0x2d0 kernel/locking/rwsem.c:1522 iterate_supers+0xa4/0x1d0 fs/super.c:755 ksys_sync+0x9d/0x170 fs/sync.c:102 __ia32_sys_sync+0xa/0x10 fs/sync.c:113 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f0e0019ce59 RSP: 002b:00007f0e00f6e028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f0e00415fa0 RCX: 00007f0e0019ce59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f0e00415fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f0e00416038 R14: 00007f0e00415fa0 R15: 00007ffebb291d58 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cb2e770 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8cb2ef90 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/27: #0: ffffffff8cb2dde0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2dde0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2dde0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513 2 locks held by getty/4030: #0: ffff88814d04d098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x429/0x1390 drivers/tty/n_tty.c:2198 4 locks held by syz.0.1617/9249: 1 lock held by syz.1.2122/10675: #0: ffff88807280a0e0 (&type->s_umount_key#31){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:755 2 locks held by kworker/1:20/13649: #0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 #1: ffffc900038f7d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 2 locks held by syz.2.3144/13726: #0: ffffffff97024038 (nfnl_subsys_ipset){+.+.}-{3:3}, at: call_ad+0x289/0xb10 net/netfilter/ipset/ip_set_core.c:1748 #1: ffffffff8cb33ab8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #1: ffffffff8cb33ab8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2ec/0x890 kernel/rcu/tree_exp.h:962 2 locks held by sed/13771: ============================================= 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+0x188/0x24e lib/dump_stack.c:106 nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xeee/0xf30 kernel/hung_task.c:377 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 9249 Comm: syz.0.1617 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:__lock_is_held kernel/locking/lockdep.c:5400 [inline] RIP: 0010:lock_is_held_type+0xbd/0x190 kernel/locking/lockdep.c:5705 Code: 31 e4 49 83 fc 31 73 24 4c 89 ff 4c 89 f6 e8 2a 02 00 00 85 c0 75 2a 49 ff c4 48 63 83 d8 0a 00 00 49 83 c7 28 49 39 c4 7c d8 11 48 c7 c7 00 c1 9f 8c 4c 89 e6 e8 e2 2f 0b fa eb cb 31 ed eb RSP: 0018:ffffc90003336bf8 EFLAGS: 00000046 RAX: 0000000000000004 RBX: ffff888024c2bb80 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8cb2dea0 RDI: ffff888024c2c6d8 RBP: 00000000ffffffff R08: ffffffff8e1ffbef R09: 1ffffffff1c3ff7d R10: dffffc0000000000 R11: fffffbfff1c3ff7e R12: 0000000000000004 R13: 0000000000000046 R14: ffffffff8cb2dea0 R15: ffff888024c2c700 FS: 00007f247a9ae6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff454f787b8 CR3: 000000005c710000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_is_held include/linux/lockdep.h:283 [inline] rcu_read_lock_sched_held+0x86/0x110 kernel/rcu/update.c:125 task_css include/linux/cgroup.h:509 [inline] task_ca kernel/sched/cpuacct.c:39 [inline] cpuacct_charge+0x113/0x310 kernel/sched/cpuacct.c:341 cgroup_account_cputime include/linux/cgroup.h:792 [inline] update_curr+0x3be/0x970 kernel/sched/fair.c:915 put_prev_entity+0x45/0x420 kernel/sched/fair.c:5051 pick_next_task_fair+0x337/0x680 kernel/sched/fair.c:7866 __pick_next_task kernel/sched/core.c:5871 [inline] pick_next_task kernel/sched/core.c:5946 [inline] __schedule+0x689/0x40e0 kernel/sched/core.c:6525 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6874 irqentry_exit+0x63/0x70 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:__sanitizer_cov_trace_pc+0x4b/0x60 kernel/kcov.c:222 Code: 75 35 83 b9 1c 16 00 00 00 74 2c 8b 91 f8 15 00 00 83 fa 02 75 21 48 8b 91 00 16 00 00 48 8b 32 48 8d 7e 01 8b 89 fc 15 00 00 <48> 39 cf 73 08 48 89 3a 48 89 44 f2 08 c3 0f 1f 80 00 00 00 00 48 RSP: 0018:ffffc90003337178 EFLAGS: 00000246 RAX: ffffffff81ac6096 RBX: ffff888017933ef8 RCX: 0000000000080000 RDX: ffffc90005149000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc90003337288 R08: ffffffff8e1ffbef R09: 1ffffffff1c3ff7d R10: dffffc0000000000 R11: fffffbfff1c3ff7e R12: 1ffff92000666e38 R13: dffffc0000000000 R14: 000000000000000c R15: 0000000000000007 __filemap_get_folio+0x86/0xdb0 mm/filemap.c:1939 pagecache_get_page+0x26/0x250 mm/folio-compat.c:110 find_or_create_page include/linux/pagemap.h:648 [inline] grow_dev_page fs/buffer.c:946 [inline] grow_buffers fs/buffer.c:1011 [inline] __getblk_slow fs/buffer.c:1038 [inline] __getblk_gfp+0x2d8/0xb20 fs/buffer.c:1333 sb_getblk include/linux/buffer_head.h:356 [inline] ext4_getblk+0x279/0x6f0 fs/ext4/inode.c:902 ext4_bread+0x26/0x170 fs/ext4/inode.c:948 ext4_quota_write+0x236/0x580 fs/ext4/super.c:7228 v2_write_file_info+0x249/0x390 fs/quota/quota_v2.c:213 dquot_acquire+0x400/0x520 fs/quota/dquot.c:475 ext4_acquire_dquot+0x2d9/0x4a0 fs/ext4/super.c:6837 dqget+0x778/0xeb0 fs/quota/dquot.c:988 __dquot_initialize+0x3c3/0xcd0 fs/quota/dquot.c:1517 ext4_process_orphan+0x54/0x300 fs/ext4/orphan.c:327 ext4_orphan_cleanup+0xbeb/0x1420 fs/ext4/orphan.c:472 __ext4_fill_super fs/ext4/super.c:5574 [inline] ext4_fill_super+0x6ee3/0x78c0 fs/ext4/super.c:5693 get_tree_bdev+0x3f1/0x610 fs/super.c:1366 vfs_get_tree+0x88/0x270 fs/super.c:1573 do_new_mount+0x24a/0xa40 fs/namespace.c:3078 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f2479b9e0ca Code: 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f247a9ade58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f247a9adee0 RCX: 00007f2479b9e0ca RDX: 0000200000000180 RSI: 0000200000000000 RDI: 00007f247a9adea0 RBP: 0000200000000180 R08: 00007f247a9adee0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000000000 R13: 00007f247a9adea0 R14: 000000000000061f R15: 00002000000000c0 vkms_vblank_simulate: vblank timer overrun