INFO: task syz-executor:4271 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:22096 pid:4271 ppid:1 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 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x562/0xaf0 kernel/locking/mutex.c:747 lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1444 jfs_umount+0x28f/0x360 fs/jfs/jfs_umount.c:116 jfs_put_super+0x88/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x130/0x340 fs/super.c:501 kill_block_super+0x7c/0xe0 fs/super.c:1470 deactivate_locked_super+0x93/0xf0 fs/super.c:332 cleanup_mnt+0x42c/0x4b0 fs/namespace.c:1191 task_work_run+0x1d0/0x260 kernel/task_work.c:203 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+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f232fb9e017 RSP: 002b:00007ffd0b3e2878 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f232fc32120 RCX: 00007f232fb9e017 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd0b3e2930 RBP: 00007ffd0b3e2930 R08: 00007ffd0b3e3930 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd0b3e39c0 R13: 00007f232fc32120 R14: 000000000006e2a4 R15: 00007ffd0b3e3a00 INFO: task syz-executor:7735 blocked for more than 145 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21808 pid:7735 ppid:1 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 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x562/0xaf0 kernel/locking/mutex.c:747 lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1444 jfs_umount+0x28f/0x360 fs/jfs/jfs_umount.c:116 jfs_put_super+0x88/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x130/0x340 fs/super.c:501 kill_block_super+0x7c/0xe0 fs/super.c:1470 deactivate_locked_super+0x93/0xf0 fs/super.c:332 cleanup_mnt+0x42c/0x4b0 fs/namespace.c:1191 task_work_run+0x1d0/0x260 kernel/task_work.c:203 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+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fcc0819e017 RSP: 002b:00007ffdac02d6c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fcc08232120 RCX: 00007fcc0819e017 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffdac02d780 RBP: 00007ffdac02d780 R08: 00007ffdac02e780 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffdac02e810 R13: 00007fcc08232120 R14: 000000000006cd62 R15: 00007ffdac02e850 INFO: task syz-executor:7737 blocked for more than 145 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:22096 pid:7737 ppid:1 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 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x562/0xaf0 kernel/locking/mutex.c:747 lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1444 jfs_umount+0x28f/0x360 fs/jfs/jfs_umount.c:116 jfs_put_super+0x88/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x130/0x340 fs/super.c:501 kill_block_super+0x7c/0xe0 fs/super.c:1470 deactivate_locked_super+0x93/0xf0 fs/super.c:332 cleanup_mnt+0x42c/0x4b0 fs/namespace.c:1191 task_work_run+0x1d0/0x260 kernel/task_work.c:203 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+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fef6a99e017 RSP: 002b:00007ffe64f5a208 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fef6aa32120 RCX: 00007fef6a99e017 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe64f5a2c0 RBP: 00007ffe64f5a2c0 R08: 00007ffe64f5b2c0 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe64f5b350 R13: 00007fef6aa32120 R14: 00000000000709bd R15: 00007ffe64f5b390 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cb2df70 (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: ffffffff8cb2e790 (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/28: #0: ffffffff8cb2d5e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2d5e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2d5e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513 2 locks held by getty/4028: #0: ffff88814d1c6098 (&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 2 locks held by syz-executor/4270: #0: ffff888054c000e0 (&type->s_umount_key#64){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362 #1: ffffffff8cf2ae08 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/4271: #0: ffff88807859e0e0 (&type->s_umount_key#64){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362 #1: ffffffff8cf2ae08 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by kworker/0:5/4320: #0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 #1: ffffc900044c7d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 4 locks held by kworker/u4:6/4328: #0: ffff888017616938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 #1: ffffc90004507d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 #2: ffffffff8dd3b050 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x148/0xba0 net/core/net_namespace.c:594 #3: ffffffff8cb33180 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x48/0x600 kernel/rcu/tree.c:4023 4 locks held by kworker/u4:17/6273: 2 locks held by syz-executor/7735: #0: ffff8880576b80e0 (&type->s_umount_key#64){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362 #1: ffffffff8cf2ae08 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/7737: #0: ffff888027c100e0 (&type->s_umount_key#64){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362 #1: ffffffff8cf2ae08 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/8371: #0: ffff8880730d60e0 (&type->s_umount_key#64){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362 #1: ffffffff8cf2ae08 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/8375: #0: ffff888027d420e0 (&type->s_umount_key#64){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362 #1: ffffffff8cf2ae08 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/8445: #0: ffff8880543c00e0 (&type->s_umount_key#64){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362 #1: ffffffff8cf2ae08 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by kworker/u4:21/8520: 2 locks held by syz.6.1228/9585: #0: ffff888056019410 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #0: ffff888056019410 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:653 [inline] #0: ffff888056019410 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1399 #1: ffffffff8cb332b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #1: ffffffff8cb332b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2ec/0x890 kernel/rcu/tree_exp.h:962 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 9585 Comm: syz.6.1228 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:memset+0x22/0x40 mm/kasan/shadow.c:47 Code: 00 00 00 e9 90 ec ff ff 55 41 56 53 48 89 d3 89 f5 49 89 fe 48 8b 4c 24 18 48 89 d6 ba 01 00 00 00 e8 72 ec ff ff 84 c0 74 11 <4c> 89 f7 89 ee 48 89 da 5b 41 5e 5d e9 ad 91 4e 08 31 c0 5b 41 5e RSP: 0018:ffffc900045970b0 EFLAGS: 00000202 RAX: 0000000000000001 RBX: 0000000000000010 RCX: ffffffff813925ba RDX: 0000000000000001 RSI: 0000000000000010 RDI: ffffc900045971f8 RBP: 0000000000000000 R08: ffffc90004597207 R09: 1ffff920008b2e40 R10: dffffc0000000000 R11: fffff520008b2e41 R12: 1ffff920008b2e36 R13: dffffc0000000000 R14: ffffc900045971f8 R15: ffffc900045971dd FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00002000000003b0 CR3: 000000003c3dd000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_next_frame+0xb8a/0x20b0 arch/x86/kernel/unwind_orc.c:546 arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122 save_stack+0x121/0x230 mm/page_owner.c:127 __reset_page_owner+0x51/0x1a0 mm/page_owner.c:148 reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1486 [inline] free_pcp_prepare mm/page_alloc.c:1536 [inline] free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3413 free_unref_page_list+0xbb/0x8e0 mm/page_alloc.c:3554 release_pages+0x1fa6/0x2220 mm/swap.c:1035 tlb_batch_pages_flush mm/mmu_gather.c:60 [inline] tlb_flush_mmu_free mm/mmu_gather.c:255 [inline] tlb_flush_mmu+0x105/0x220 mm/mmu_gather.c:262 tlb_finish_mmu+0xf5/0x220 mm/mmu_gather.c:394 exit_mmap+0x384/0x960 mm/mmap.c:3262 __mmput+0x118/0x3c0 kernel/fork.c:1205 exit_mm+0x1fe/0x2d0 kernel/exit.c:565 do_exit+0x905/0x2480 kernel/exit.c:867 do_group_exit+0x217/0x2d0 kernel/exit.c:1022 get_signal+0x1272/0x1350 kernel/signal.c:2871 arch_do_signal_or_restart+0xc4/0x1350 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f9a5879cdd9 Code: Unable to access opcode bytes at 0x7f9a5879cdaf. RSP: 002b:00007f9a59581028 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: 0000000000000000 RBX: 00007f9a58a15fa0 RCX: 00007f9a5879cdd9 RDX: 0000000000000005 RSI: 0000000000000107 RDI: 0000000000000009 RBP: 00007f9a58832d69 R08: 000000000000001c R09: 0000000000000000 R10: 00002000000000c0 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f9a58a16038 R14: 00007f9a58a15fa0 R15: 00007fff368b8068