INFO: task syz-executor.4:8045 blocked for more than 143 seconds. Not tainted 6.10.0-rc3-syzkaller-00021-g2ef5971ff345 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:27184 pid:8045 tgid:8041 ppid:5110 flags:0x00000006 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6837 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x5b8/0x9c0 kernel/locking/mutex.c:752 __fdget_pos+0xeb/0x180 fs/file.c:1191 fdget_pos include/linux/file.h:76 [inline] __do_sys_getdents64 fs/readdir.c:405 [inline] __se_sys_getdents64 fs/readdir.c:394 [inline] __x64_sys_getdents64+0x117/0x2e0 fs/readdir.c:394 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7faf0c47cea9 RSP: 002b:00007faf0d1320c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 00007faf0c5b4050 RCX: 00007faf0c47cea9 RDX: 0000000000000018 RSI: 0000000000000000 RDI: 000000000000000d RBP: 00007faf0c4ebff4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007faf0c5b4050 R15: 00007ffdddca0048 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8dbb1920 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #0: ffffffff8dbb1920 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #0: ffffffff8dbb1920 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6614 3 locks held by kworker/1:1/45: 2 locks held by getty/4840: #0: ffff88802f1e00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc8/0x1490 drivers/tty/n_tty.c:2201 3 locks held by syz-fuzzer/5083: 3 locks held by kworker/1:5/5164: #0: ffff888015480948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12bf/0x1b60 kernel/workqueue.c:3206 #1: ffffc900037efd80 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x957/0x1b60 kernel/workqueue.c:3207 #2: ffffffff8dbbd0b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:291 3 locks held by syz-executor.4/8044: 1 lock held by syz-executor.4/8045: #0: ffff88807d455248 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xeb/0x180 fs/file.c:1191 1 lock held by syz-executor.1/9678: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 30 Comm: khungtaskd Not tainted 6.10.0-rc3-syzkaller-00021-g2ef5971ff345 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xf86/0x1240 kernel/hung_task.c:379 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 7772 Comm: syz-executor.0 Not tainted 6.10.0-rc3-syzkaller-00021-g2ef5971ff345 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 RIP: 0010:__sanitizer_cov_trace_pc+0x18/0x60 kernel/kcov.c:203 Code: 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 65 48 8b 15 e4 f3 75 7e 65 8b 05 e5 f3 75 7e a9 00 01 ff 00 <48> 8b 34 24 74 0f f6 c4 01 74 35 8b 82 1c 16 00 00 85 c0 74 2b 8b RSP: 0018:ffffc90002f0f670 EFLAGS: 00000246 RAX: 0000000080000001 RBX: ffffc90002f0f740 RCX: ffffffff813cd516 RDX: ffff888017bdbc00 RSI: ffffffff813cd675 RDI: 0000000000000005 RBP: ffffc90002f0f958 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffc90002f0f748 R13: ffffc90002f0f750 R14: 0000000000000001 R15: ffffc90002f10000 FS: 0000000000000000(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f886ed26000 CR3: 000000001f544000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: stack_access_ok+0xf9/0x270 arch/x86/kernel/unwind_orc.c:389 deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline] unwind_next_frame+0x1b94/0x23a0 arch/x86/kernel/unwind_orc.c:648 arch_stack_walk+0x100/0x170 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 save_stack+0x162/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x8d/0x400 mm/page_owner.c:297 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1088 [inline] free_unref_page+0x64a/0xe40 mm/page_alloc.c:2583 vfree+0x181/0x7a0 mm/vmalloc.c:3346 kcov_put kernel/kcov.c:429 [inline] kcov_put+0x2a/0x40 kernel/kcov.c:425 kcov_close+0x10/0x20 kernel/kcov.c:525 __fput+0x408/0xbb0 fs/file_table.c:422 task_work_run+0x14e/0x250 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa9b/0x2ba0 kernel/exit.c:874 do_group_exit+0xd3/0x2a0 kernel/exit.c:1023 get_signal+0x2616/0x2710 kernel/signal.c:2909 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x14a/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8ff6a7bb4c Code: Unable to access opcode bytes at 0x7f8ff6a7bb22. RSP: 002b:00007ffda75b3dd0 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: fffffffffffffe00 RBX: 0000000000000003 RCX: 00007f8ff6a7bb4c RDX: 0000000000000038 RSI: 00007f8ff6bb0020 RDI: 00000000000000f9 RBP: 00007ffda75b3e4c R08: 0000000000000000 R09: 0079746972756365 R10: 00007f8ff6b846a0 R11: 0000000000000246 R12: 0000000000000032 R13: 0000000000085e49 R14: 0000000000085a53 R15: 0000000000000010