INFO: task syz-executor:5912 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21608 pid:5912 ppid:1 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5380 [inline] __schedule+0x14d2/0x44d0 kernel/sched/core.c:6699 schedule+0xbd/0x170 kernel/sched/core.c:6773 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6832 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x6b7/0xcc0 kernel/locking/mutex.c:747 lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444 jfs_umount+0x2ef/0x3c0 fs/jfs/jfs_umount.c:114 jfs_put_super+0x8c/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x134/0x2b0 fs/super.c:693 kill_block_super+0x44/0x90 fs/super.c:1660 deactivate_locked_super+0x97/0x100 fs/super.c:481 cleanup_mnt+0x429/0x4c0 fs/namespace.c:1259 task_work_run+0x1ce/0x250 kernel/task_work.c:239 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xf6/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f5637f90a77 RSP: 002b:00007ffeeb816f78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f5638013d7d RCX: 00007f5637f90a77 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffeeb817030 RBP: 00007ffeeb817030 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffeeb8180c0 R13: 00007f5638013d7d R14: 00000000000342a1 R15: 00007ffeeb818100 Showing all locks held in the system: 1 lock held by ksoftirqd/1/22: 1 lock held by khungtaskd/29: #0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 2 locks held by kworker/u4:9/4552: 2 locks held by getty/5527: #0: ffff88802d2af0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217 2 locks held by syz-executor/5912: #0: ffff88802caee0e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88802caee0e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88802caee0e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 #1: ffffffff8d147928 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/5914: #0: ffff88802c0320e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88802c0320e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88802c0320e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 #1: ffffffff8d147928 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/6018: #0: ffff88807a6be0e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88807a6be0e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88807a6be0e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 #1: ffffffff8d147928 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/6046: #0: ffff88807e1100e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88807e1100e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88807e1100e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 #1: ffffffff8d147928 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/6047: #0: ffff888078dfc0e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff888078dfc0e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff888078dfc0e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 #1: ffffffff8d147928 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/6066: #0: ffff88807a9320e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88807a9320e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88807a9320e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 #1: ffffffff8d147928 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/6126: #0: ffff88807dad00e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88807dad00e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88807dad00e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 #1: ffffffff8d147928 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/6159: #0: ffff88807dd1a0e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88807dd1a0e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88807dd1a0e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 #1: ffffffff8d147928 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/6176: #0: ffff8880798de0e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff8880798de0e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff8880798de0e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 #1: ffffffff8d147928 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444 1 lock held by syz-executor/6178: #0: ffff8880196980e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff8880196980e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff8880196980e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 5 locks held by syz.3.251/6540: 2 locks held by syz.6.252/6541: 4 locks held by syz.4.253/6542: 2 locks held by syz.2.254/6543: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 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+0x16c/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x39b/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf41/0xf80 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 6543 Comm: syz.2.254 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:__sanitizer_cov_trace_switch+0x74/0x120 kernel/kcov.c:-1 Code: 00 b9 07 00 00 00 48 85 c0 75 13 e9 bc 00 00 00 b9 01 00 00 00 48 85 c0 0f 84 ae 00 00 00 41 57 41 56 41 54 53 48 8b 54 24 20 <65> 4c 8b 05 c4 1f 7e 7e 45 31 c9 eb 08 49 ff c1 4c 39 c8 74 77 4e RSP: 0018:ffffc9000da7ee50 EFLAGS: 00000206 RAX: 0000000000000003 RBX: ffffffff8ed7a578 RCX: 0000000000000003 RDX: ffffffff813aba19 RSI: ffffffff8cb9e7e0 RDI: 0000000000000001 RBP: ffffc9000da7ef98 R08: ffffc9000da7efa7 R09: 0000000000000000 R10: ffffc9000da7ef98 R11: fffff52001b4fdf5 R12: ffffc9000da7ef48 R13: dffffc0000000000 R14: 0000000000000001 R15: ffffffff8ed7a57c FS: 0000555580091500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000023d000 CR3: 00000000482ee000 CR4: 00000000003506e0 Call Trace: unwind_next_frame+0x16d9/0x2970 arch/x86/kernel/unwind_orc.c:641 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 save_stack+0xf7/0x1f0 mm/page_owner.c:128 __set_page_owner+0x1d/0x60 mm/page_owner.c:192 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554 prep_new_page mm/page_alloc.c:1561 [inline] get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457 __folio_alloc+0x10/0x20 mm/page_alloc.c:4489 vma_alloc_folio+0x47a/0x8f0 mm/mempolicy.c:2242 shmem_alloc_folio+0x179/0x230 mm/shmem.c:1679 shmem_alloc_and_acct_folio+0x189/0x630 mm/shmem.c:1704 shmem_get_folio_gfp+0xcde/0x2ac0 mm/shmem.c:2041 shmem_get_folio mm/shmem.c:2164 [inline] shmem_write_begin+0xf2/0x420 mm/shmem.c:2706 generic_perform_write+0x2fb/0x5b0 mm/filemap.c:4031 shmem_file_write_iter+0xfb/0x120 mm/shmem.c:2883 do_iter_readv_writev fs/read_write.c:-1 [inline] do_iter_write+0x79a/0xc70 fs/read_write.c:860 vfs_writev fs/read_write.c:933 [inline] do_pwritev+0x205/0x340 fs/read_write.c:1030 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f7f7ef8f749 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007ffd6c381a08 EFLAGS: 00000246 ORIG_RAX: 0000000000000148 RAX: ffffffffffffffda RBX: 00007f7f7f1e5fa0 RCX: 00007f7f7ef8f749 RDX: 0000000000000001 RSI: 0000200000000240 RDI: 0000000000000003 RBP: 00007f7f7f013f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000007800 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7f7f1e5fa0 R14: 00007f7f7f1e5fa0 R15: 0000000000000006