INFO: task khugepaged:1050 blocked for more than 143 seconds. Not tainted 5.1.0-rc7+ #100 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. khugepaged D25624 1050 2 0x80000000 Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x813/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:582 [inline] rwsem_down_write_failed+0x774/0xc30 kernel/locking/rwsem-xadd.c:611 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0x53/0x90 kernel/locking/rwsem.c:72 collapse_huge_page+0x22b/0x3f60 mm/khugepaged.c:1006 khugepaged_scan_pmd mm/khugepaged.c:1215 [inline] khugepaged_scan_mm_slot mm/khugepaged.c:1725 [inline] khugepaged_do_scan mm/khugepaged.c:1806 [inline] khugepaged+0x28c3/0x3f40 mm/khugepaged.c:1851 kthread+0x357/0x430 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 INFO: task syz-fuzzer:7811 blocked for more than 143 seconds. Not tainted 5.1.0-rc7+ #100 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-fuzzer D24352 7811 7807 0x00000000 Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x813/0x1cc0 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: 0033:0x42280d Code: b8 ff ff ff ff ff ff ff 7f 48 39 c6 76 61 48 c7 c2 d4 ff ff ff 64 c7 02 22 00 00 00 e9 1c fd ff ff 49 0f be 74 24 01 48 8b 05 fa 0c 00 83 3c b0 58 74 59 85 d2 0f 85 78 fd ff ff c6 44 24 13 RSP: 002b:000000c420037dc0 EFLAGS: 00010206 RAX: 00007fe2dbd34000 RBX: 00007fe2dbd32ef0 RCX: 000000c43538a000 RDX: 0000000000000001 RSI: 00000000000000ae RDI: 000000c420026380 RBP: 000000c420037df0 R08: 0000000000000004 R09: 0000000000000003 R10: 0000000000bfbe20 R11: 0000000000000010 R12: 0000000000000002 R13: 0000000000000018 R14: 0000000000000013 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/1043: #0: 0000000073ac4385 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5057 1 lock held by khugepaged/1050: #0: 00000000fbee6b48 (&mm->mmap_sem){++++}, at: collapse_huge_page+0x22b/0x3f60 mm/khugepaged.c:1006 1 lock held by rsyslogd/7697: #0: 00000000cc19d243 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/7788: #0: 000000006baea494 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000ecfda7e8 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7789: #0: 00000000ea60b72b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000009e6980bc (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7790: #0: 0000000081ba38b3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000003b02a8f8 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7791: #0: 00000000a106e316 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000732c6dee (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7792: #0: 00000000ee8825e9 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000a5eb546d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7793: #0: 00000000556e02c1 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000002b5ebfb5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7794: #0: 000000000849cbe5 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000036a92fe9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 1 lock held by syz-fuzzer/7811: #0: 00000000fbee6b48 (&mm->mmap_sem){++++}, at: do_user_addr_fault arch/x86/mm/fault.c:1426 [inline] #0: 00000000fbee6b48 (&mm->mmap_sem){++++}, at: __do_page_fault+0x9e9/0xda0 arch/x86/mm/fault.c:1541 1 lock held by syz-fuzzer/7822: 1 lock held by syz-executor.3/15061: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1043 Comm: khungtaskd Not tainted 5.1.0-rc7+ #100 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: