Warning: Permanently added '10.128.0.249' (ECDSA) to the list of known hosts. syzkaller login: [ 235.087524][ T942] INFO: task khugepaged:1085 blocked for more than 143 seconds. [ 235.095340][ T942] Not tainted 5.4.0-rc5-next-20191031 #0 [ 235.101599][ T942] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 235.111854][ T942] khugepaged D27840 1085 2 0x80004000 [ 235.118242][ T942] Call Trace: [ 235.125942][ T942] __schedule+0x94a/0x1e70 [ 235.130427][ T942] ? __sched_text_start+0x8/0x8 [ 235.135548][ T942] ? blk_insert_cloned_request+0x530/0x530 [ 235.141399][ T942] ? _raw_spin_unlock_irq+0x23/0x80 [ 235.146791][ T942] ? __lock_page+0x3d9/0xab0 [ 235.151451][ T942] ? _raw_spin_unlock_irq+0x23/0x80 [ 235.156934][ T942] schedule+0xdc/0x2b0 [ 235.161051][ T942] io_schedule+0x1c/0x70 [ 235.165300][ T942] __lock_page+0x422/0xab0 [ 235.169780][ T942] ? wait_on_page_bit+0xa60/0xa60 [ 235.174808][ T942] ? page_cache_next_miss+0x340/0x340 [ 235.180232][ T942] ? ___might_sleep+0x163/0x2c0 [ 235.185086][ T942] ? __might_sleep+0x95/0x190 [ 235.189827][ T942] mpage_prepare_extent_to_map+0xb3f/0xf90 [ 235.195650][ T942] ? mpage_process_page_bufs+0x780/0x780 [ 235.201340][ T942] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 235.207376][ T942] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 235.213703][ T942] ext4_writepages+0xb6a/0x2e70 [ 235.218588][ T942] ? __this_cpu_preempt_check+0x2c/0x190 [ 235.224279][ T942] ? ext4_mark_inode_dirty+0x9b0/0x9b0 [ 235.229789][ T942] ? 0xffffffff81000000 [ 235.234000][ T942] ? mark_lock+0xc2/0x1220 [ 235.238508][ T942] ? prep_new_page+0x19f/0x200 [ 235.243283][ T942] ? wbc_attach_and_unlock_inode+0x515/0x920 [ 235.249316][ T942] ? find_held_lock+0x35/0x130 [ 235.254109][ T942] ? wbc_attach_and_unlock_inode+0x515/0x920 [ 235.260123][ T942] ? ext4_mark_inode_dirty+0x9b0/0x9b0 [ 235.265585][ T942] do_writepages+0xfa/0x2a0 [ 235.270119][ T942] ? do_writepages+0xfa/0x2a0 [ 235.274797][ T942] ? lock_downgrade+0x920/0x920 [ 235.279693][ T942] ? page_writeback_cpu_online+0x20/0x20 [ 235.285321][ T942] ? __kasan_check_read+0x11/0x20 [ 235.290387][ T942] ? do_raw_spin_unlock+0x57/0x270 [ 235.295503][ T942] ? _raw_spin_unlock+0x28/0x40 [ 235.300385][ T942] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 235.306660][ T942] ? wbc_attach_and_unlock_inode+0x5bf/0x920 [ 235.312756][ T942] __filemap_fdatawrite_range+0x2bc/0x3b0 [ 235.318515][ T942] ? delete_from_page_cache_batch+0xfe0/0xfe0 [ 235.324588][ T942] ? lockdep_hardirqs_on+0x421/0x5e0 [ 235.329911][ T942] filemap_flush+0x24/0x30 [ 235.334332][ T942] collapse_file+0x36b1/0x41a0 [ 235.339135][ T942] ? rcu_lockdep_current_cpu_online+0xe3/0x130 [ 235.345301][ T942] ? khugepaged+0x21c0/0x4360 [ 235.350029][ T942] ? trace_event_raw_event_mm_collapse_huge_page_isolate+0x370/0x370 [ 235.358152][ T942] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 235.363975][ T942] ? khugepaged_find_target_node+0x142/0x180 [ 235.370003][ T942] khugepaged+0x2da9/0x4360 [ 235.374518][ T942] ? __kasan_check_read+0x11/0x20 [ 235.379583][ T942] ? __lock_acquire+0x16f2/0x4a00 [ 235.384625][ T942] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 235.390317][ T942] ? lock_downgrade+0x920/0x920 [ 235.395170][ T942] ? finish_wait+0x260/0x260 [ 235.399785][ T942] ? lockdep_hardirqs_on+0x421/0x5e0 [ 235.405062][ T942] ? trace_hardirqs_on+0x67/0x240 [ 235.410141][ T942] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 235.416383][ T942] ? __kthread_parkme+0x108/0x1c0 [ 235.421442][ T942] ? __kasan_check_read+0x11/0x20 [ 235.426472][ T942] kthread+0x361/0x430 [ 235.430598][ T942] ? collapse_pte_mapped_thp+0xbe0/0xbe0 [ 235.436244][ T942] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 235.442013][ T942] ret_from_fork+0x24/0x30 [ 235.446537][ T942] [ 235.446537][ T942] Showing all locks held in the system: [ 235.454438][ T942] 1 lock held by khungtaskd/942: [ 235.459426][ T942] #0: ffffffff88faba40 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279 [ 235.468817][ T942] 4 locks held by kworker/u4:6/981: [ 235.474013][ T942] #0: ffff8880a8780528 ((wq_completion)writeback){+.+.}, at: process_one_work+0x88b/0x1740 [ 235.484149][ T942] #1: ffff8880a7997dc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0x8c1/0x1740 [ 235.495520][ T942] #2: ffff88809ac520d8 (&type->s_umount_key#32){++++}, at: trylock_super+0x22/0x110 [ 235.505038][ T942] #3: ffff88809ac54990 (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0xfa/0x2a0 [ 235.514958][ T942] 1 lock held by khugepaged/1085: [ 235.520023][ T942] #0: ffff88809ac54990 (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0xfa/0x2a0 [ 235.529925][ T942] 1 lock held by rsyslogd/8623: [ 235.534775][ T942] #0: ffff8880945b35e0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 [ 235.543423][ T942] 2 locks held by getty/8713: [ 235.548148][ T942] #0: ffff88809e222090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 235.557095][ T942] #1: ffffc90005f052e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 235.566732][ T942] 2 locks held by getty/8714: [ 235.571436][ T942] #0: ffff8880920d4090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 235.580413][ T942] #1: ffffc90005f192e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 235.590084][ T942] 2 locks held by getty/8715: [ 235.594753][ T942] #0: ffff8880a8377090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 235.603726][ T942] #1: ffffc90005f212e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 235.613345][ T942] 2 locks held by getty/8716: [ 235.618067][ T942] #0: ffff88808d642090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 235.627016][ T942] #1: ffffc90005f252e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 235.636633][ T942] 2 locks held by getty/8717: [ 235.641335][ T942] #0: ffff8880928c5090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 235.650456][ T942] #1: ffffc90005f292e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 235.660817][ T942] 2 locks held by getty/8718: [ 235.665582][ T942] #0: ffff8880a2237090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 235.674736][ T942] #1: ffffc90005f1d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 235.684608][ T942] 2 locks held by getty/8719: [ 235.690723][ T942] #0: ffff8880a420b090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 [ 235.700961][ T942] #1: ffffc90005ef92e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 [ 235.714650][ T942] 1 lock held by syz-execprog/8739: [ 235.720272][ T942] #0: ffff8880a663d368 (&ei->i_mmap_sem){++++}, at: ext4_filemap_fault+0x7e/0xb2 [ 235.731616][ T942] [ 235.734035][ T942] ============================================= [ 235.734035][ T942] [ 235.743390][ T942] NMI backtrace for cpu 0 [ 235.749171][ T942] CPU: 0 PID: 942 Comm: khungtaskd Not tainted 5.4.0-rc5-next-20191031 #0 [ 235.757838][ T942] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 235.768860][ T942] Call Trace: [ 235.772165][ T942] dump_stack+0x172/0x1f0 [ 235.776623][ T942] nmi_cpu_backtrace.cold+0x70/0xb2 [ 235.781816][ T942] ? vprintk_func+0x86/0x189 [ 235.786398][ T942] ? lapic_can_unplug_cpu.cold+0x3a/0x3a [ 235.792022][ T942] nmi_trigger_cpumask_backtrace+0x23b/0x28b [ 235.798005][ T942] arch_trigger_cpumask_backtrace+0x14/0x20 [ 235.803978][ T942] watchdog+0xc8f/0x1350 [ 235.809008][ T942] kthread+0x361/0x430 [ 235.813066][ T942] ? reset_hung_task_detector+0x30/0x30 [ 235.819200][ T942] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 235.825092][ T942] ret_from_fork+0x24/0x30 [ 235.829665][ T942] Sending NMI from CPU 0 to CPUs 1: [ 235.834917][ C1] NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0xe/0x10 [ 235.835866][ T942] Kernel panic - not syncing: hung_task: blocked tasks [ 235.850011][ T942] CPU: 0 PID: 942 Comm: khungtaskd Not tainted 5.4.0-rc5-next-20191031 #0 [ 235.858490][ T942] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 235.868533][ T942] Call Trace: [ 235.871822][ T942] dump_stack+0x172/0x1f0 [ 235.876140][ T942] panic+0x2e3/0x75c [ 235.880023][ T942] ? add_taint.cold+0x16/0x16 [ 235.884693][ T942] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 235.890404][ T942] ? printk_safe_flush+0xf2/0x140 [ 235.895423][ T942] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 235.901654][ T942] ? nmi_trigger_cpumask_backtrace+0x224/0x28b [ 235.907877][ T942] ? nmi_trigger_cpumask_backtrace+0x21b/0x28b [ 235.914027][ T942] watchdog+0xca0/0x1350 [ 235.918270][ T942] kthread+0x361/0x430 [ 235.922328][ T942] ? reset_hung_task_detector+0x30/0x30 [ 235.927874][ T942] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 235.933595][ T942] ret_from_fork+0x24/0x30 [ 235.940404][ T942] Kernel Offset: disabled [ 235.945858][ T942] Rebooting in 86400 seconds..