INFO: task syz-executor1:15116 blocked for more than 140 seconds. Not tainted 4.19.0-rc8+ #75 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor1 D23248 15116 5534 0x00000004 Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473 schedule+0xfe/0x460 kernel/sched/core.c:3517 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:269 [inline] rwsem_down_read_failed+0x362/0x610 kernel/locking/rwsem-xadd.c:286 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+0xbe/0x1d0 kernel/locking/rwsem.c:26 __do_page_fault+0xb70/0xed0 arch/x86/mm/fault.c:1331 do_page_fault+0xf2/0x7e0 arch/x86/mm/fault.c:1470 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1161 RIP: 0033:0x43e897 Code: cf 01 00 48 8b 04 24 48 8b 4c 24 20 48 89 41 30 48 89 c8 eb c9 e8 c9 b6 01 00 eb 97 cc cc cc cc cc cc cc 64 48 8b 0c 25 f8 ff ff 48 3b 61 10 76 34 48 83 ec 20 48 89 6c 24 18 48 8d 6c 24 18 RSP: 002b:00007fffd8a94f38 EFLAGS: 00010202 RAX: 0000000020000180 RBX: 000000000072c040 RCX: 78756e696c65732f RDX: 0000000000000010 RSI: 0000000000731508 RDI: 0000000020000180 RBP: fffffffffffffffe R08: 007373656363612f R09: 0000000000000000 R10: 00007fffd8a94ff0 R11: 0000000000000246 R12: 000000000072c04c R13: 000000000072c04c R14: 0000000000000003 R15: 0000000000000002 INFO: task syz-executor1:15160 blocked for more than 140 seconds. Not tainted 4.19.0-rc8+ #75 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor1 D22024 15160 5534 0x80000004 Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473 schedule+0xfe/0x460 kernel/sched/core.c:3517 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:269 [inline] rwsem_down_read_failed+0x362/0x610 kernel/locking/rwsem-xadd.c:286 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+0xbe/0x1d0 kernel/locking/rwsem.c:26 exit_mm kernel/exit.c:511 [inline] do_exit+0x59c/0x26d0 kernel/exit.c:854 do_group_exit+0x177/0x440 kernel/exit.c:970 get_signal+0x8b0/0x1980 kernel/signal.c:2513 do_signal+0x9c/0x21e0 arch/x86/kernel/signal.c:816 exit_to_usermode_loop+0x2e5/0x380 arch/x86/entry/common.c:162 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457569 Code: 83 c4 18 c3 e8 d8 64 00 00 48 8b 04 24 48 8b 4c 24 08 48 89 01 e8 d7 2d fc ff e8 22 7a fc ff b8 02 00 00 00 48 8d 0d 2a 60 09 <01> 87 01 8b 05 22 60 09 01 83 f8 01 0f 85 8a 00 00 00 b8 01 00 00 RSP: 002b:00007fad9eab8cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 000000000072c048 RCX: 0000000000457569 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000072c048 RBP: 000000000072c040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000072c04c R13: 00007fffd8a94ebf R14: 00007fad9eab99c0 R15: 0000000000000002 INFO: task syz-executor1:15161 blocked for more than 140 seconds. Not tainted 4.19.0-rc8+ #75 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor1 D23368 15161 5534 0x80000004 Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473 schedule+0xfe/0x460 kernel/sched/core.c:3517 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:269 [inline] rwsem_down_read_failed+0x362/0x610 kernel/locking/rwsem-xadd.c:286 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+0xbe/0x1d0 kernel/locking/rwsem.c:26 exit_mm kernel/exit.c:511 [inline] do_exit+0x59c/0x26d0 kernel/exit.c:854 do_group_exit+0x177/0x440 kernel/exit.c:970 get_signal+0x8b0/0x1980 kernel/signal.c:2513 do_signal+0x9c/0x21e0 arch/x86/kernel/signal.c:816 exit_to_usermode_loop+0x2e5/0x380 arch/x86/entry/common.c:162 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457569 Code: 83 c4 18 c3 e8 d8 64 00 00 48 8b 04 24 48 8b 4c 24 08 48 89 01 e8 d7 2d fc ff e8 22 7a fc ff b8 02 00 00 00 48 8d 0d 2a 60 09 <01> 87 01 8b 05 22 60 09 01 83 f8 01 0f 85 8a 00 00 00 b8 01 00 00 RSP: 002b:00007fad9ea97cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 000000000072c0e8 RCX: 0000000000457569 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000072c0e8 RBP: 000000000072c0e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000072c0ec R13: 00007fffd8a94ebf R14: 00007fad9ea989c0 R15: 0000000000000003 Showing all locks held in the system: 1 lock held by khungtaskd/981: #0: 000000004cd3260e (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4435 1 lock held by rsyslogd/5358: #0: 00000000e87a7cf4 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 2 locks held by getty/5480: #0: 000000008b833752 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000088b1c966 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5481: #0: 00000000fdd536c3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000004e313f50 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5482: #0: 00000000bda0b954 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000003bd4a1b7 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5483: #0: 00000000bbeae207 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000054e66401 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5484: #0: 00000000c44f87b1 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000437ad539 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5485: #0: 00000000cfdc48c7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000ccd4cb14 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5486: #0: 000000006929e58d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000b6aa5122 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 1 lock held by syz-executor1/15116: #0: 00000000b5cfdff3 (&mm->mmap_sem){++++}, at: __do_page_fault+0xb70/0xed0 arch/x86/mm/fault.c:1331 1 lock held by syz-executor1/15130: 1 lock held by syz-executor1/15160: #0: 00000000b5cfdff3 (&mm->mmap_sem){++++}, at: exit_mm kernel/exit.c:511 [inline] #0: 00000000b5cfdff3 (&mm->mmap_sem){++++}, at: do_exit+0x59c/0x26d0 kernel/exit.c:854 1 lock held by syz-executor1/15161: #0: 00000000b5cfdff3 (&mm->mmap_sem){++++}, at: exit_mm kernel/exit.c:511 [inline] #0: 00000000b5cfdff3 (&mm->mmap_sem){++++}, at: do_exit+0x59c/0x26d0 kernel/exit.c:854 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 981 Comm: khungtaskd Not tainted 4.19.0-rc8+ #75 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+0x1c4/0x2b6 lib/dump_stack.c:113 nmi_cpu_backtrace.cold.3+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x1ed 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:144 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline] watchdog+0xb3e/0x1050 kernel/hung_task.c:265 kthread+0x35a/0x420 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:57