INFO: task syz.4.257:8387 blocked for more than 143 seconds. Not tainted 6.16.0-rc5-syzkaller-00038-g733923397fd9 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.257 state:D stack:25128 pid:8387 tgid:8386 ppid:7594 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5401 [inline] __schedule+0x16a2/0x4cb0 kernel/sched/core.c:6790 __schedule_loop kernel/sched/core.c:6868 [inline] schedule+0x165/0x360 kernel/sched/core.c:6883 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6940 rwsem_down_read_slowpath+0x552/0x880 kernel/locking/rwsem.c:1084 __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1526 __super_lock fs/super.c:59 [inline] super_lock+0x2a9/0x3b0 fs/super.c:121 user_get_super+0xc8/0x120 fs/super.c:998 quotactl_block fs/quota/quota.c:890 [inline] __do_sys_quotactl fs/quota/quota.c:955 [inline] __se_sys_quotactl+0x4da/0x950 fs/quota/quota.c:917 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbb89d8e929 RSP: 002b:00007fbb8aba8038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3 RAX: ffffffffffffffda RBX: 00007fbb89fb5fa0 RCX: 00007fbb89d8e929 RDX: 0000000000000000 RSI: 0000200000000340 RDI: ffffffff80000800 RBP: 00007fbb89e10b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000200000000140 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fbb89fb5fa0 R15: 00007ffecacc9368 Showing all locks held in the system: 3 locks held by kworker/u8:1/13: 1 lock held by khungtaskd/31: #0: ffffffff8e13f160 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13f160 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13f160 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 5 locks held by udevd/5209: 2 locks held by getty/5599: #0: ffff88814cd070a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 2 locks held by syz-executor/5845: 2 locks held by kworker/0:4/5887: 1 lock held by syz.4.257/8387: #0: ffff88807a0940e0 (&type->s_umount_key#59){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff88807a0940e0 (&type->s_umount_key#59){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121 1 lock held by syz.6.268/8556: #0: ffff88807a0940e0 (&type->s_umount_key#59){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff88807a0940e0 (&type->s_umount_key#59){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121 1 lock held by syz-executor/9905: #0: ffffffff8e144c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #0: ffffffff8e144c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998 3 locks held by syz.7.499/10421: 2 locks held by syz.7.499/10443: #0: ffff888079540428 (sb_writers#5){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline] #0: ffff888079540428 (sb_writers#5){.+.+}-{0:0}, at: vfs_fallocate+0x62a/0x830 fs/open.c:340 #1: ffff8880483db708 (&sb->s_type->i_mutex_key#12){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline] #1: ffff8880483db708 (&sb->s_type->i_mutex_key#12){+.+.}-{4:4}, at: shmem_fallocate+0x144/0xde0 mm/shmem.c:3663 3 locks held by syz.7.499/10444: 2 locks held by syz.0.500/10424: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc5-syzkaller-00038-g733923397fd9 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:470 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 10424 Comm: syz.0.500 Not tainted 6.16.0-rc5-syzkaller-00038-g733923397fd9 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:unwind_next_frame+0x16d/0x2390 arch/x86/kernel/unwind_orc.c:494 Code: d8 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 45 1b 00 00 f6 03 03 0f 85 e4 17 00 00 49 8d 5e 35 48 89 d8 48 c1 e8 03 48 89 44 24 28 <0f> b6 04 28 84 c0 0f 85 3c 1b 00 00 4c 89 6c 24 50 4c 89 64 24 20 RSP: 0018:ffffc90000007658 EFLAGS: 00000807 RAX: 1ffff92000000eeb RBX: ffffc9000000775d RCX: ddaf9c16f4db8f00 RDX: 0000000000000000 RSI: ffffffff8be1ca20 RDI: ffffffff8be1c9e0 RBP: dffffc0000000000 R08: 0000000000000000 R09: ffffffff81729ae5 R10: ffffc90000007778 R11: ffffffff81acf290 R12: 1ffff92000000ee5 R13: ffffc90000007778 R14: ffffc90000007728 R15: ffffffff81729ae5 FS: 00007fb8b73256c0(0000) GS:ffff888125c4f000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000676000 CR3: 0000000078578000 CR4: 00000000003526f0 Call Trace: arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:47 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:548 insert_work+0x3d/0x330 kernel/workqueue.c:2183 __queue_work+0xcfc/0xfe0 kernel/workqueue.c:2341 call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1793 [inline] __run_timers kernel/time/timer.c:2372 [inline] __run_timer_base+0x646/0x860 kernel/time/timer.c:2384 run_timer_base kernel/time/timer.c:2393 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403 handle_softirqs+0x283/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:seqcount_lockdep_reader_access+0x129/0x180 include/linux/seqlock.h:75 Code: 92 b2 ff 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4b 41 f7 c5 00 02 00 00 74 01 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 27 00 00 00 00 66 43 c7 44 27 09 00 00 43 c6 44 27 0b 00 RSP: 0018:ffffc9000b527360 EFLAGS: 00000206 RAX: ddaf9c16f4db8f00 RBX: ffff88813fffc3d8 RCX: ddaf9c16f4db8f00 RDX: 0000000000000006 RSI: ffffffff8d984d62 RDI: ffffffff8be1ca40 RBP: ffffc9000b527408 R08: ffffffff8fa0c5f7 R09: 1ffffffff1f418be R10: dffffc0000000000 R11: fffffbfff1f418bf R12: dffffc0000000000 R13: 0000000000000a06 R14: ffffffff821516fb R15: 1ffff920016a4e6c read_seqbegin include/linux/seqlock.h:836 [inline] zone_span_seqbegin include/linux/memory_hotplug.h:103 [inline] page_outside_zone_boundaries mm/page_alloc.c:442 [inline] bad_range+0x8b/0x2c0 mm/page_alloc.c:461 rmqueue mm/page_alloc.c:3157 [inline] get_page_from_freelist+0x21b3/0x22b0 mm/page_alloc.c:3666 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4959 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2419 folio_alloc_mpol_noprof+0x39/0x70 mm/mempolicy.c:2438 shmem_alloc_folio mm/shmem.c:1851 [inline] shmem_alloc_and_add_folio+0x447/0xf60 mm/shmem.c:1890 shmem_get_folio_gfp+0x59d/0x1660 mm/shmem.c:2536 shmem_get_folio mm/shmem.c:2642 [inline] shmem_write_begin+0xf7/0x2b0 mm/shmem.c:3292 generic_perform_write+0x2c4/0x910 mm/filemap.c:4112 shmem_file_write_iter+0xf8/0x120 mm/shmem.c:3467 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x548/0xa90 fs/read_write.c:686 ksys_write+0x145/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb8b658d3df Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48 RSP: 002b:00007fb8b7324df0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007fb8b658d3df RDX: 0000000001000000 RSI: 00007fb8abe00000 RDI: 0000000000000005 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000004439 R10: 00002000000088c2 R11: 0000000000000293 R12: 0000000000000005 R13: 00007fb8b7324ef0 R14: 00007fb8b7324eb0 R15: 00007fb8abe00000