INFO: task syz-executor.3:5867 blocked for more than 143 seconds. Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.3 state:D stack:30192 pid:5867 tgid:5854 ppid:5101 flags:0x00000006 Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0xf15/0x5c70 kernel/sched/core.c:6736 __schedule_loop kernel/sched/core.c:6813 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6828 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6885 __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_getdents fs/readdir.c:322 [inline] __se_sys_getdents fs/readdir.c:311 [inline] __x64_sys_getdents+0x117/0x2d0 fs/readdir.c:311 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x7f1e1be7dda9 RSP: 002b:00007f1e1cbb80c8 EFLAGS: 00000246 ORIG_RAX: 000000000000004e RAX: ffffffffffffffda RBX: 00007f1e1bfac120 RCX: 00007f1e1be7dda9 RDX: 0000000000000028 RSI: 0000000020000080 RDI: 0000000000000007 RBP: 00007f1e1beca47a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f1e1bfac120 R15: 00007ffd5959fbb8 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8d7b08e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #0: ffffffff8d7b08e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #0: ffffffff8d7b08e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6614 2 locks held by kworker/u8:2/42: 3 locks held by udevd/4512: 2 locks held by getty/4817: #0: ffff88802aa990a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900015c02f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc8/0x1490 drivers/tty/n_tty.c:2201 1 lock held by syz-executor.1/5089: 3 locks held by syz-executor.2/5110: 2 locks held by syz-executor.3/5858: 1 lock held by syz-executor.3/5867: #0: ffff88802e1fad48 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xeb/0x180 fs/file.c:1191 3 locks held by syz-executor.3/6358: 4 locks held by syz-executor.4/7566: 2 locks held by udevd/9209: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 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:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf86/0x1210 kernel/hung_task.c:379 kthread+0x2c1/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 24 Comm: kworker/1:0 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 Workqueue: events nsim_dev_trap_report_work RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:26 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:173 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0xc/0x60 kernel/kcov.c:207 Code: c3 cc cc cc cc 66 0f 1f 84 00 00 00 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 04 db 76 7e <65> 8b 05 05 db 76 7e a9 00 01 ff 00 48 8b 34 24 74 0f f6 c4 01 74 RSP: 0018:ffffc900001e7758 EFLAGS: 00000287 RAX: 0000000000000179 RBX: ffffc900001e77e0 RCX: ffffffff813c990d RDX: ffff888017a90000 RSI: ffffffff813c991b RDI: ffffffff90de32ec RBP: 0000000000000001 R08: 0000000000000004 R09: 000000000000004f R10: 00000000000a0000 R11: 0000000000000004 R12: ffffffff81004ff9 R13: ffffffff90257e4a R14: 000000000000015b R15: ffffc900001e7815 FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa7ed08cd58 CR3: 0000000030aa6000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: orc_find arch/x86/kernel/unwind_orc.c:220 [inline] unwind_next_frame+0x2f6/0x23a0 arch/x86/kernel/unwind_orc.c:494 arch_stack_walk+0x100/0x170 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:240 [inline] __kasan_slab_free+0x11d/0x1a0 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2106 [inline] slab_free mm/slub.c:4280 [inline] kmem_cache_free+0x12e/0x360 mm/slub.c:4344 kfree_skbmem+0x10e/0x200 net/core/skbuff.c:1159 __kfree_skb net/core/skbuff.c:1217 [inline] consume_skb net/core/skbuff.c:1432 [inline] consume_skb+0xdf/0x170 net/core/skbuff.c:1426 nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline] nsim_dev_trap_report_work+0x878/0xc80 drivers/net/netdevsim/dev.c:850 process_one_work+0x9a9/0x1a60 kernel/workqueue.c:3254 process_scheduled_works kernel/workqueue.c:3335 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3416 kthread+0x2c1/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243