INFO: task syz.2.1230:10380 blocked for more than 143 seconds. Not tainted 6.15.0-rc2-syzkaller-00258-g750d0ac001e8 #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.1230 state:D stack:25344 pid:10380 tgid:10371 ppid:5840 task_flags:0x40044c flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1b88/0x5240 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x163/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 rwsem_down_write_slowpath+0xedd/0x1420 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write+0x1da/0x220 kernel/locking/rwsem.c:1578 mmap_write_lock include/linux/mmap_lock.h:128 [inline] exit_mmap+0x305/0xde0 mm/mmap.c:1292 __mmput+0x115/0x420 kernel/fork.c:1379 exit_mm+0x221/0x310 kernel/exit.c:589 do_exit+0x994/0x27f0 kernel/exit.c:940 do_group_exit+0x207/0x2c0 kernel/exit.c:1102 get_signal+0x1696/0x1730 kernel/signal.c:3034 arch_do_signal_or_restart+0x98/0x810 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x210 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3db218e169 RSP: 002b:00007f3db2f230e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f3db23b6168 RCX: 00007f3db218e169 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f3db23b6168 RBP: 00007f3db23b6160 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3db23b616c R13: 0000000000000000 R14: 00007ffc7b673160 R15: 00007ffc7b673248 Showing all locks held in the system: 4 locks held by kworker/u8:1/13: #0: ffff88801bef6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801bef6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc90000127c60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000127c60 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffffffff900f0ad0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x17c/0xd60 net/core/net_namespace.c:608 #3: ffffffff8ed43300 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3774 1 lock held by khungtaskd/31: #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6764 2 locks held by kworker/1:1/52: #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc90000bd7c60 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000bd7c60 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 3 locks held by kworker/u8:9/2993: 2 locks held by getty/5596: #0: ffff8880364a10a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000334b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5bb/0x1700 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5840: #0: ffff8880257565e0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:128 [inline] #0: ffff8880257565e0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x305/0xde0 mm/mmap.c:1292 1 lock held by syz-executor/5845: #0: ffff888025756fe0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:128 [inline] #0: ffff888025756fe0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x305/0xde0 mm/mmap.c:1292 1 lock held by syz-executor/5849: #0: ffff888033e0bde0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:128 [inline] #0: ffff888033e0bde0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x305/0xde0 mm/mmap.c:1292 1 lock held by syz.2.1230/10380: #0: ffff88807d93c7e0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:128 [inline] #0: ffff88807d93c7e0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x305/0xde0 mm/mmap.c:1292 1 lock held by syz-executor/15753: #0: ffffffff8ed43438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #0: ffffffff8ed43438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x454/0x830 kernel/rcu/tree_exp.h:998 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc2-syzkaller-00258-g750d0ac001e8 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x4ab/0x4e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0x1058/0x10a0 kernel/hung_task.c:437 kthread+0x7b7/0x940 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5195 Comm: syslogd Not tainted 6.15.0-rc2-syzkaller-00258-g750d0ac001e8 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:check_preemption_disabled+0x2/0x120 lib/smp_processor_id.c:13 Code: b5 a1 8c 48 c7 c6 80 b5 a1 8c eb 1c 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 57 <41> 56 41 55 41 54 53 48 83 ec 10 4c 8d 25 9c b0 38 07 65 49 8b 04 RSP: 0018:ffffc900033776e8 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 0000000000000001 RCX: 0000000080000000 RDX: ffff88804f70da00 RSI: ffffffff8e4db511 RDI: ffffffff8ca1b5a0 RBP: ffffffff93686020 R08: ffffffff8c2d2bda R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff88804f70da00 R13: 0000000000000246 R14: 00000000ffffffff R15: ffffffff8ed3df20 FS: 00007f8e07f0f380(0000) GS:ffff88812509a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8208fdb440 CR3: 0000000035118000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:472 [inline] lock_is_held_type+0x112/0x1a0 kernel/locking/lockdep.c:5939 xa_entry include/linux/xarray.h:1220 [inline] xas_descend lib/xarray.c:208 [inline] xas_load+0x47e/0x5c0 lib/xarray.c:246 filemap_get_entry+0x1f2/0x3b0 mm/filemap.c:1859 shmem_get_folio_gfp+0x288/0x1800 mm/shmem.c:2457 shmem_get_folio mm/shmem.c:2639 [inline] shmem_write_begin+0x17e/0x3a0 mm/shmem.c:3289 generic_perform_write+0x329/0xa10 mm/filemap.c:4103 shmem_file_write_iter+0xf9/0x120 mm/shmem.c:3464 new_sync_write fs/read_write.c:591 [inline] vfs_write+0x70f/0xd10 fs/read_write.c:684 ksys_write+0x19d/0x2d0 fs/read_write.c:736 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8e08063bf2 Code: 89 c7 48 89 44 24 08 e8 7b 34 fa ff 48 8b 44 24 08 48 83 c4 28 c3 c3 64 8b 04 25 18 00 00 00 85 c0 75 20 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 6f 48 8b 15 07 a2 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffc7e5afd68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f8e08063bf2 RDX: 000000000000005b RSI: 0000563bf8f66c50 RDI: 0000000000000003 RBP: 0000563bf8f66c50 R08: 0000000000000001 R09: 0000000000000000 R10: 00007f8e082023a3 R11: 0000000000000246 R12: 000000000000005b R13: 00007f8e07f0f300 R14: 0000000000000004 R15: 0000563bf8f66a60