INFO: task syz.4.183:5206 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.183 state:D stack:25728 pid:5206 ppid:4270 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6696 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x555/0xaf0 kernel/locking/mutex.c:747 sync_bdevs+0x1ab/0x320 block/bdev.c:1054 ksys_sync+0xb6/0x150 fs/sync.c:105 __ia32_sys_sync+0xa/0x10 fs/sync.c:113 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f349398f749 RSP: 002b:00007f34947ee038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f3493be5fa0 RCX: 00007f349398f749 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f3493be5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3493be6038 R14: 00007f3493be5fa0 R15: 00007ffe27e8e4f8 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cb2b630 (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: ffffffff8cb2be50 (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: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513 2 locks held by getty/4025: #0: ffff88802fce5098 (&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+0x41b/0x1380 drivers/tty/n_tty.c:2198 1 lock held by udevd/4258: #0: ffff8880249e14c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x13d/0xa60 block/bdev.c:815 2 locks held by kworker/0:16/4936: 6 locks held by kworker/u4:15/4954: #0: ffff8880b8e3aad8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xa5/0x140 kernel/sched/core.c:545 #1: ffffc9000c1dfd00 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #2: ffff8880b8e28418 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x6bf/0xd00 kernel/time/timer.c:1112 #3: ffffffff8cbc6d48 (jump_label_mutex){+.+.}-{3:3}, at: jump_label_lock kernel/jump_label.c:27 [inline] #3: ffffffff8cbc6d48 (jump_label_mutex){+.+.}-{3:3}, at: static_key_enable_cpuslocked+0xc2/0x240 kernel/jump_label.c:204 #4: ffffffff8c9dc988 (text_mutex){+.+.}-{3:3}, at: arch_jump_label_transform_apply+0xe/0x20 arch/x86/kernel/jump_label.c:145 #5: ffff888017466078 (ptlock_ptr(page)#2){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] #5: ffff888017466078 (ptlock_ptr(page)#2){+.+.}-{2:2}, at: __get_locked_pte+0x162/0x1b0 mm/memory.c:1850 1 lock held by syz.4.183/5206: #0: ffff8880249e14c8 (&disk->open_mutex){+.+.}-{3:3}, at: sync_bdevs+0x1ab/0x320 block/bdev.c:1054 1 lock held by syz-executor/6110: 2 locks held by syz.3.440/6773: 3 locks held by dhcpcd-run-hook/6775: ============================================= 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 10/25/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 nmi_cpu_backtrace+0x3f4/0x470 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: 6110 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:check_region_inline mm/kasan/generic.c:169 [inline] RIP: 0010:kasan_check_range+0xd/0x290 mm/kasan/generic.c:189 Code: c3 0f 0b b8 ea ff ff ff c3 0f 0b b8 ea ff ff ff c3 00 00 cc cc 00 00 cc cc 00 00 cc cc b0 01 48 85 f6 0f 84 a4 01 00 00 41 57 <41> 56 53 49 89 f8 49 01 f0 0f 82 57 02 00 00 49 89 f8 49 c1 e8 2f RSP: 0018:ffffc90003227710 EFLAGS: 00000002 RAX: ffffffff81cb1001 RBX: ffffea00011bbe00 RCX: ffffffff81cb103b RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffea00011bbe00 RBP: ffffc900032278b8 R08: dffffc0000000000 R09: fffff940002377c7 R10: fffff940002377c7 R11: 1ffffd40002377c6 R12: 1ffffd40002377c0 R13: dffffc0000000000 R14: 00fff60000080017 R15: dffffc0000000000 FS: 0000555594df4500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f50913b6ad8 CR3: 000000004b729000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read include/linux/instrumented.h:72 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] PageHead include/linux/page-flags.h:794 [inline] PageHeadHuge+0x5b/0x1c0 mm/hugetlb.c:2122 folio_test_hugetlb include/linux/page-flags.h:837 [inline] filemap_unaccount_folio+0x31/0xa80 mm/filemap.c:178 __filemap_remove_folio+0xbb/0x860 mm/filemap.c:222 filemap_remove_folio+0xed/0x2c0 mm/filemap.c:255 truncate_inode_folio+0x59/0x70 mm/truncate.c:195 shmem_undo_range+0x4d2/0x2050 mm/shmem.c:942 shmem_truncate_range mm/shmem.c:1062 [inline] shmem_evict_inode+0x248/0xa40 mm/shmem.c:1171 evict+0x485/0x870 fs/inode.c:705 do_unlinkat+0x377/0x560 fs/namei.c:4405 __do_sys_unlink fs/namei.c:4446 [inline] __se_sys_unlink fs/namei.c:4444 [inline] __x64_sys_unlink+0x45/0x50 fs/namei.c:4444 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f63cb98ecf7 Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 57 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fffc1615898 EFLAGS: 00000206 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f63cb98ecf7 RDX: 00007fffc16158c0 RSI: 00007fffc1615950 RDI: 00007fffc1615950 RBP: 00007fffc1615950 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000206 R12: 00007fffc16169e0 R13: 00007f63cba13d7d R14: 00000000000474c4 R15: 00007fffc1616a20