INFO: task syz-executor969:8122 blocked for more than 143 seconds. Not tainted 5.1.0-rc4+ #65 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor969 D23920 8122 8121 0x00000000 Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x817/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:285 [inline] rwsem_down_read_failed+0x213/0x420 kernel/locking/rwsem-xadd.c:302 call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94 __down_read arch/x86/include/asm/rwsem.h:83 [inline] down_read+0x49/0x90 kernel/locking/rwsem.c:26 do_user_addr_fault arch/x86/mm/fault.c:1426 [inline] __do_page_fault+0x9e9/0xda0 arch/x86/mm/fault.c:1541 do_page_fault+0x71/0x581 arch/x86/mm/fault.c:1572 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1143 RIP: 0033:0x4ad510 Code: Bad RIP value. RSP: 002b:00007ffeca29cf48 EFLAGS: 00010202 RAX: 00000000004ad510 RBX: 0000000000000001 RCX: 00000000006e27b0 RDX: 00000000004088d0 RSI: 0000000000000001 RDI: 00000000004cedf0 RBP: 00007ffeca29cf50 R08: 00000000006dbfb0 R09: 00000000006dbfb0 R10: 00007ffeca29cfd0 R11: 0000000000000000 R12: 0000000000000001 R13: 00000000006e27a0 R14: 000000000000002d R15: 0000000000000006 Showing all locks held in the system: 1 lock held by khungtaskd/1039: #0: 0000000002a816fb (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5061 1 lock held by rsyslogd/7971: #0: 0000000087322ba9 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/8093: #0: 0000000015ef38c7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000004fe72512 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8094: #0: 000000003efce27c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000002f94ed0f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8095: #0: 0000000002926a81 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000c7c48c76 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8096: #0: 0000000087fa386a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000100107b6 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8097: #0: 00000000c7a879bb (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000002802b64a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8098: #0: 0000000098f38e6a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000b317aac2 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8099: #0: 0000000086d314db (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000067ae6b54 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 1 lock held by syz-executor969/8122: #0: 00000000b0e46ea1 (&mm->mmap_sem){++++}, at: do_user_addr_fault arch/x86/mm/fault.c:1426 [inline] #0: 00000000b0e46ea1 (&mm->mmap_sem){++++}, at: __do_page_fault+0x9e9/0xda0 arch/x86/mm/fault.c:1541 2 locks held by syz-executor969/8128: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1039 Comm: khungtaskd Not tainted 5.1.0-rc4+ #65 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1be/0x236 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline] watchdog+0x9b7/0xec0 kernel/hung_task.c:288 kthread+0x357/0x430 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: