INFO: task khugepaged:908 blocked for more than 140 seconds. Not tainted 4.18.0-rc4+ #138 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. khugepaged D22472 908 2 0x80000000 Call Trace: context_switch kernel/sched/core.c:2853 [inline] __schedule+0x87c/0x1ed0 kernel/sched/core.c:3501 schedule+0xfb/0x450 kernel/sched/core.c:3545 __rwsem_down_write_failed_common+0x95d/0x1630 kernel/locking/rwsem-xadd.c:566 rwsem_down_write_failed+0xe/0x10 kernel/locking/rwsem-xadd.c:595 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+0xaa/0x130 kernel/locking/rwsem.c:72 collapse_huge_page+0x2b9/0x2140 mm/khugepaged.c:1006 khugepaged_scan_pmd mm/khugepaged.c:1215 [inline] khugepaged_scan_mm_slot+0x20a1/0x3370 mm/khugepaged.c:1734 khugepaged_do_scan mm/khugepaged.c:1815 [inline] khugepaged+0x9aa/0xce0 mm/khugepaged.c:1860 kthread+0x345/0x410 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 INFO: task syz-fuzzer:4571 blocked for more than 140 seconds. Not tainted 4.18.0-rc4+ #138 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-fuzzer D19640 4571 4563 0x00000000 Call Trace: context_switch kernel/sched/core.c:2853 [inline] __schedule+0x87c/0x1ed0 kernel/sched/core.c:3501 schedule+0xfb/0x450 kernel/sched/core.c:3545 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:269 [inline] rwsem_down_read_failed+0x362/0x600 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] __percpu_down_read+0x16e/0x210 kernel/locking/percpu-rwsem.c:85 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:49 [inline] percpu_down_read include/linux/percpu-rwsem.h:59 [inline] __sb_start_write+0x2d7/0x300 fs/super.c:1403 sb_start_pagefault include/linux/fs.h:1583 [inline] ext4_page_mkwrite+0x1d0/0x1430 fs/ext4/inode.c:6126 do_page_mkwrite+0x14e/0x520 mm/memory.c:2380 wp_page_shared mm/memory.c:2676 [inline] do_wp_page+0xf78/0x19b0 mm/memory.c:2776 handle_pte_fault mm/memory.c:3988 [inline] __handle_mm_fault+0x2a84/0x4460 mm/memory.c:4096 handle_mm_fault+0x53e/0xc80 mm/memory.c:4133 __do_page_fault+0x620/0xe50 arch/x86/mm/fault.c:1396 do_page_fault+0xf6/0x8c0 arch/x86/mm/fault.c:1471 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1160 RIP: 0033:0x70b5e1 Code: Bad RIP value. RSP: 002b:000000c4291b54b0 EFLAGS: 00010212 RAX: 000000c4291b57f0 RBX: 000000c4291b57f8 RCX: 00007fd7f4d61000 RDX: 000000000000073b RSI: 0000000000000000 RDI: 0000000000000908 RBP: 000000c4291b54c0 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000095bf8a R11: 0000000000000004 R12: 0000000000000000 R13: 0000000000000020 R14: 0000000000000013 R15: 000000c4291b5960 INFO: task syz-fuzzer:4578 blocked for more than 140 seconds. Not tainted 4.18.0-rc4+ #138 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-fuzzer D19640 4578 4563 0x00000000 Call Trace: context_switch kernel/sched/core.c:2853 [inline] __schedule+0x87c/0x1ed0 kernel/sched/core.c:3501 schedule+0xfb/0x450 kernel/sched/core.c:3545 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:269 [inline] rwsem_down_read_failed+0x362/0x600 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] __percpu_down_read+0x16e/0x210 kernel/locking/percpu-rwsem.c:85 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:49 [inline] percpu_down_read include/linux/percpu-rwsem.h:59 [inline] __sb_start_write+0x2d7/0x300 fs/super.c:1403 sb_start_pagefault include/linux/fs.h:1583 [inline] ext4_page_mkwrite+0x1d0/0x1430 fs/ext4/inode.c:6126 do_page_mkwrite+0x14e/0x520 mm/memory.c:2380 wp_page_shared mm/memory.c:2676 [inline] do_wp_page+0xf78/0x19b0 mm/memory.c:2776 handle_pte_fault mm/memory.c:3988 [inline] __handle_mm_fault+0x2a84/0x4460 mm/memory.c:4096 handle_mm_fault+0x53e/0xc80 mm/memory.c:4133 __do_page_fault+0x620/0xe50 arch/x86/mm/fault.c:1396 do_page_fault+0xf6/0x8c0 arch/x86/mm/fault.c:1471 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1160 RIP: 0033:0x70b5e1 Code: Bad RIP value. RSP: 002b:000000c42ab00e00 EFLAGS: 00010212 RAX: 000000c42ab01140 RBX: 000000c42ab01148 RCX: 00007fd7ef361000 RDX: 0000000000000745 RSI: 0000000000000000 RDI: 00000000000001a0 RBP: 000000c42ab00e10 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000095bf8a R11: 0000000000000004 R12: 0000000000000000 R13: 0000000000000020 R14: 0000000000000013 R15: 000000c42ab012c0 INFO: task syz-executor1:4593 blocked for more than 140 seconds. Not tainted 4.18.0-rc4+ #138 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor1 D21336 4593 4584 0x00000000 Call Trace: context_switch kernel/sched/core.c:2853 [inline] __schedule+0x87c/0x1ed0 kernel/sched/core.c:3501 schedule+0xfb/0x450 kernel/sched/core.c:3545 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:269 [inline] rwsem_down_read_failed+0x362/0x600 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] __percpu_down_read+0x16e/0x210 kernel/locking/percpu-rwsem.c:85 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:49 [inline] percpu_down_read include/linux/percpu-rwsem.h:59 [inline] __sb_start_write+0x2d7/0x300 fs/super.c:1403 sb_start_write include/linux/fs.h:1554 [inline] mnt_want_write+0x3f/0xc0 fs/namespace.c:386 do_unlinkat+0x2b7/0xa30 fs/namei.c:4055 __do_sys_unlink fs/namei.c:4120 [inline] __se_sys_unlink fs/namei.c:4118 [inline] __x64_sys_unlink+0x42/0x50 fs/namei.c:4118 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x455b77 Code: Bad RIP value. RSP: 002b:00007ffd13e2f558 EFLAGS: 00000202 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000455b77 RDX: 00007ffd13e2f560 RSI: 00007ffd13e2f5f0 RDI: 00007ffd13e2f5f0 RBP: 00007ffd13e31300 R08: 0000000000000000 R09: 000000000000000c R10: 0000000000000006 R11: 0000000000000202 R12: 00000000024ae940 R13: 0000000000000000 R14: 00007ffd13e30cd0 R15: 0000000000702140 INFO: task syz-executor7:4595 blocked for more than 140 seconds. Not tainted 4.18.0-rc4+ #138 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor7 D21232 4595 4586 0x00000000 Call Trace: context_switch kernel/sched/core.c:2853 [inline] __schedule+0x87c/0x1ed0 kernel/sched/core.c:3501 schedule+0xfb/0x450 kernel/sched/core.c:3545 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:269 [inline] rwsem_down_read_failed+0x362/0x600 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] __percpu_down_read+0x16e/0x210 kernel/locking/percpu-rwsem.c:85 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:49 [inline] percpu_down_read include/linux/percpu-rwsem.h:59 [inline] __sb_start_write+0x2d7/0x300 fs/super.c:1403 sb_start_write include/linux/fs.h:1554 [inline] mnt_want_write+0x3f/0xc0 fs/namespace.c:386 do_unlinkat+0x2b7/0xa30 fs/namei.c:4055 __do_sys_unlink fs/namei.c:4120 [inline] __se_sys_unlink fs/namei.c:4118 [inline] __x64_sys_unlink+0x42/0x50 fs/namei.c:4118 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x455b77 Code: Bad RIP value. RSP: 002b:00007ffda2b920e8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000455b77 RDX: 00007ffda2b920f0 RSI: 00007ffda2b92180 RDI: 00007ffda2b92180 RBP: 00007ffda2b93e90 R08: 0000000000000000 R09: 000000000000000c R10: 0000000000000006 R11: 0000000000000206 R12: 00000000012b0940 R13: 0000000000000000 R14: 00007ffda2b93860 R15: 0000000000702140 INFO: task syz-executor2:4596 blocked for more than 140 seconds. Not tainted 4.18.0-rc4+ #138 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor2 D21352 4596 4588 0x00000000 Call Trace: context_switch kernel/sched/core.c:2853 [inline] __schedule+0x87c/0x1ed0 kernel/sched/core.c:3501 schedule+0xfb/0x450 kernel/sched/core.c:3545 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:269 [inline] rwsem_down_read_failed+0x362/0x600 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] __percpu_down_read+0x16e/0x210 kernel/locking/percpu-rwsem.c:85 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:49 [inline] percpu_down_read include/linux/percpu-rwsem.h:59 [inline] __sb_start_write+0x2d7/0x300 fs/super.c:1403 sb_start_write include/linux/fs.h:1554 [inline] mnt_want_write+0x3f/0xc0 fs/namespace.c:386 do_unlinkat+0x2b7/0xa30 fs/namei.c:4055 __do_sys_unlink fs/namei.c:4120 [inline] __se_sys_unlink fs/namei.c:4118 [inline] __x64_sys_unlink+0x42/0x50 fs/namei.c:4118 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x455b77 Code: Bad RIP value. RSP: 002b:00007ffe82f6eb78 EFLAGS: 00000206 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000455b77 RDX: 00007ffe82f6eb80 RSI: 00007ffe82f6ec10 RDI: 00007ffe82f6ec10 RBP: 00007ffe82f70920 R08: 0000000000000000 R09: 000000000000000c R10: 0000000000000006 R11: 0000000000000206 R12: 00000000023c6940 R13: 0000000000000000 R14: 00007ffe82f702f0 R15: 0000000000702140 INFO: task syz-executor6:11230 blocked for more than 140 seconds. Not tainted 4.18.0-rc4+ #138 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor6 D24032 11230 4589 0x00000004 Call Trace: context_switch kernel/sched/core.c:2853 [inline] __schedule+0x87c/0x1ed0 kernel/sched/core.c:3501 schedule+0xfb/0x450 kernel/sched/core.c:3545 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:269 [inline] rwsem_down_read_failed+0x362/0x600 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] __percpu_down_read+0x16e/0x210 kernel/locking/percpu-rwsem.c:85 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:49 [inline] percpu_down_read include/linux/percpu-rwsem.h:59 [inline] __sb_start_write+0x2d7/0x300 fs/super.c:1403 sb_start_pagefault include/linux/fs.h:1583 [inline] ext4_page_mkwrite+0x1d0/0x1430 fs/ext4/inode.c:6126 do_page_mkwrite+0x14e/0x520 mm/memory.c:2380 wp_page_shared mm/memory.c:2676 [inline] do_wp_page+0xf78/0x19b0 mm/memory.c:2776 handle_pte_fault mm/memory.c:3988 [inline] __handle_mm_fault+0x2a84/0x4460 mm/memory.c:4096 handle_mm_fault+0x53e/0xc80 mm/memory.c:4133 __do_page_fault+0x620/0xe50 arch/x86/mm/fault.c:1396 do_page_fault+0xf6/0x8c0 arch/x86/mm/fault.c:1471 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1160 RIP: 0033:0x4084b0 Code: 00 00 2e 23 40 00 00 00 00 00 3e 23 40 00 00 00 00 00 4e 23 40 00 00 00 00 00 5e 23 40 00 00 00 00 00 6e 23 40 00 00 00 00 00 <7e> 23 40 00 00 00 00 00 8e 23 40 00 00 00 00 00 9e 23 40 00 00 00 RSP: 002b:00007ffda0095720 EFLAGS: 00010287 RAX: 0000001b32325a18 RBX: 0000000000000000 RCX: 0000001b33320000 RDX: 0000001b32325a1c RSI: 0000000000730408 RDI: 0000000000000004 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 00007ffda0095760 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000002 R14: 000000000072bea0 R15: 000000000072bea0 INFO: task syz-executor4:11241 blocked for more than 140 seconds. Not tainted 4.18.0-rc4+ #138 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor4 D24696 11241 4591 0x00000004 Call Trace: context_switch kernel/sched/core.c:2853 [inline] __schedule+0x87c/0x1ed0 kernel/sched/core.c:3501 schedule+0xfb/0x450 kernel/sched/core.c:3545 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:269 [inline] rwsem_down_read_failed+0x362/0x600 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] __percpu_down_read+0x16e/0x210 kernel/locking/percpu-rwsem.c:85 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:49 [inline] percpu_down_read include/linux/percpu-rwsem.h:59 [inline] __sb_start_write+0x2d7/0x300 fs/super.c:1403 sb_start_pagefault include/linux/fs.h:1583 [inline] ext4_page_mkwrite+0x1d0/0x1430 fs/ext4/inode.c:6126 do_page_mkwrite+0x14e/0x520 mm/memory.c:2380 wp_page_shared mm/memory.c:2676 [inline] do_wp_page+0xf78/0x19b0 mm/memory.c:2776 handle_pte_fault mm/memory.c:3988 [inline] __handle_mm_fault+0x2a84/0x4460 mm/memory.c:4096 handle_mm_fault+0x53e/0xc80 mm/memory.c:4133 __do_page_fault+0x620/0xe50 arch/x86/mm/fault.c:1396 do_page_fault+0xf6/0x8c0 arch/x86/mm/fault.c:1471 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1160 RIP: 0033:0x4084b0 Code: 00 00 2e 23 40 00 00 00 00 00 3e 23 40 00 00 00 00 00 4e 23 40 00 00 00 00 00 5e 23 40 00 00 00 00 00 6e 23 40 00 00 00 00 00 <7e> 23 40 00 00 00 00 00 8e 23 40 00 00 00 00 00 9e 23 40 00 00 00 RSP: 002b:00007ffd8b007dc0 EFLAGS: 00010283 RAX: 0000001b32521340 RBX: 0000000000000000 RCX: 0000001b33520000 RDX: 0000001b32521344 RSI: 0000000000000002 RDI: 0000000000000002 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 00007ffd8b007e00 R11: 0000000000000000 R12: 0000000000000016 R13: 0000000000000002 R14: 000000000072bea0 R15: 000000000072bea0 INFO: task syz-executor5:11247 blocked for more than 140 seconds. Not tainted 4.18.0-rc4+ #138 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor5 D24696 11247 4594 0x00000004 Call Trace: context_switch kernel/sched/core.c:2853 [inline] __schedule+0x87c/0x1ed0 kernel/sched/core.c:3501 schedule+0xfb/0x450 kernel/sched/core.c:3545 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:269 [inline] rwsem_down_read_failed+0x362/0x600 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] __percpu_down_read+0x16e/0x210 kernel/locking/percpu-rwsem.c:85 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:49 [inline] percpu_down_read include/linux/percpu-rwsem.h:59 [inline] __sb_start_write+0x2d7/0x300 fs/super.c:1403 sb_start_pagefault include/linux/fs.h:1583 [inline] ext4_page_mkwrite+0x1d0/0x1430 fs/ext4/inode.c:6126 do_page_mkwrite+0x14e/0x520 mm/memory.c:2380 wp_page_shared mm/memory.c:2676 [inline] do_wp_page+0xf78/0x19b0 mm/memory.c:2776 handle_pte_fault mm/memory.c:3988 [inline] __handle_mm_fault+0x2a84/0x4460 mm/memory.c:4096 handle_mm_fault+0x53e/0xc80 mm/memory.c:4133 __do_page_fault+0x620/0xe50 arch/x86/mm/fault.c:1396 do_page_fault+0xf6/0x8c0 arch/x86/mm/fault.c:1471 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1160 RIP: 0033:0x4084b0 Code: 00 00 2e 23 40 00 00 00 00 00 3e 23 40 00 00 00 00 00 4e 23 40 00 00 00 00 00 5e 23 40 00 00 00 00 00 6e 23 40 00 00 00 00 00 <7e> 23 40 00 00 00 00 00 8e 23 40 00 00 00 00 00 9e 23 40 00 00 00 RSP: 002b:00007fffca6dbbe0 EFLAGS: 00010283 RAX: 0000001b327205dc RBX: 0000000000000000 RCX: 0000001b33720000 RDX: 0000001b327205e0 RSI: 0000000000000001 RDI: 0000000000000001 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 00007fffca6dbc20 R11: 0000000000000000 R12: 0000000000000016 R13: 0000000000000002 R14: 000000000072bea0 R15: 000000000072bea0 INFO: task syz-executor3:11259 blocked for more than 140 seconds. Not tainted 4.18.0-rc4+ #138 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D24696 11259 4592 0x00000004 Call Trace: context_switch kernel/sched/core.c:2853 [inline] __schedule+0x87c/0x1ed0 kernel/sched/core.c:3501 schedule+0xfb/0x450 kernel/sched/core.c:3545 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:269 [inline] rwsem_down_read_failed+0x362/0x600 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] __percpu_down_read+0x16e/0x210 kernel/locking/percpu-rwsem.c:85 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:49 [inline] percpu_down_read include/linux/percpu-rwsem.h:59 [inline] __sb_start_write+0x2d7/0x300 fs/super.c:1403 sb_start_pagefault include/linux/fs.h:1583 [inline] ext4_page_mkwrite+0x1d0/0x1430 fs/ext4/inode.c:6126 do_page_mkwrite+0x14e/0x520 mm/memory.c:2380 wp_page_shared mm/memory.c:2676 [inline] do_wp_page+0xf78/0x19b0 mm/memory.c:2776 handle_pte_fault mm/memory.c:3988 [inline] __handle_mm_fault+0x2a84/0x4460 mm/memory.c:4096 handle_mm_fault+0x53e/0xc80 mm/memory.c:4133 __do_page_fault+0x620/0xe50 arch/x86/mm/fault.c:1396 do_page_fault+0xf6/0x8c0 arch/x86/mm/fault.c:1471 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1160 RIP: 0033:0x4084b0 Code: 00 00 2e 23 40 00 00 00 00 00 3e 23 40 00 00 00 00 00 4e 23 40 00 00 00 00 00 5e 23 40 00 00 00 00 00 6e 23 40 00 00 00 00 00 <7e> 23 40 00 00 00 00 00 8e 23 40 00 00 00 00 00 9e 23 40 00 00 00 RSP: 002b:00007ffdc5387730 EFLAGS: 00010287 RAX: 0000001b32221ac0 RBX: 0000000000000000 RCX: 0000001b33220000 RDX: 0000001b32221ac4 RSI: 0000000000730230 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 00007ffdc5387770 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000002 R14: 000000000072bea0 R15: 000000000072bea0 Showing all locks held in the system: 1 lock held by khungtaskd/902: #0: 00000000302dfe7d (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x428 kernel/locking/lockdep.c:4461 1 lock held by khugepaged/908: #0: 00000000112b17e2 (&mm->mmap_sem){++++}, at: collapse_huge_page+0x2b9/0x2140 mm/khugepaged.c:1006 2 locks held by rs:main Q:Reg/4451: #0: 000000002f0abaf5 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 #1: 000000009ac828fd (sb_writers#6){++++}, at: file_start_write include/linux/fs.h:2737 [inline] #1: 000000009ac828fd (sb_writers#6){++++}, at: vfs_write+0x452/0x560 fs/read_write.c:548 1 lock held by rsyslogd/4453: #0: 000000007ac2e086 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 2 locks held by getty/4543: #0: 0000000086e2fe5f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000b211e154 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4544: #0: 00000000c9613f54 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000045499135 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4545: #0: 000000005d921197 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000632fb1c7 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4546: #0: 00000000541da12f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000006bae5c28 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4547: #0: 000000005a53ae60 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000061bf96a6 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4548: #0: 00000000aecb1d06 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000c9a6c550 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4549: #0: 000000009b91956d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000064a6b906 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by syz-fuzzer/4571: #0: 00000000112b17e2 (&mm->mmap_sem){++++}, at: __do_page_fault+0x389/0xe50 arch/x86/mm/fault.c:1325 #1: 00000000cee1b88f (sb_pagefaults){++++}, at: sb_start_pagefault include/linux/fs.h:1583 [inline] #1: 00000000cee1b88f (sb_pagefaults){++++}, at: ext4_page_mkwrite+0x1d0/0x1430 fs/ext4/inode.c:6126 2 locks held by syz-fuzzer/4578: #0: 00000000112b17e2 (&mm->mmap_sem){++++}, at: __do_page_fault+0x389/0xe50 arch/x86/mm/fault.c:1325 #1: 00000000cee1b88f (sb_pagefaults){++++}, at: sb_start_pagefault include/linux/fs.h:1583 [inline] #1: 00000000cee1b88f (sb_pagefaults){++++}, at: ext4_page_mkwrite+0x1d0/0x1430 fs/ext4/inode.c:6126 1 lock held by syz-executor1/4593: #0: 000000009ac828fd (sb_writers#6){++++}, at: sb_start_write include/linux/fs.h:1554 [inline] #0: 000000009ac828fd (sb_writers#6){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 1 lock held by syz-executor7/4595: #0: 000000009ac828fd (sb_writers#6){++++}, at: sb_start_write include/linux/fs.h:1554 [inline] #0: 000000009ac828fd (sb_writers#6){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 1 lock held by syz-executor2/4596: #0: 000000009ac828fd (sb_writers#6){++++}, at: sb_start_write include/linux/fs.h:1554 [inline] #0: 000000009ac828fd (sb_writers#6){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 2 locks held by syz-executor6/11230: #0: 00000000d4e6bad3 (&mm->mmap_sem){++++}, at: __do_page_fault+0x389/0xe50 arch/x86/mm/fault.c:1325 #1: 00000000cee1b88f (sb_pagefaults){++++}, at: sb_start_pagefault include/linux/fs.h:1583 [inline] #1: 00000000cee1b88f (sb_pagefaults){++++}, at: ext4_page_mkwrite+0x1d0/0x1430 fs/ext4/inode.c:6126 2 locks held by syz-executor4/11241: #0: 00000000c6d64a1c (&mm->mmap_sem){++++}, at: __do_page_fault+0x389/0xe50 arch/x86/mm/fault.c:1325 #1: 00000000cee1b88f (sb_pagefaults){++++}, at: sb_start_pagefault include/linux/fs.h:1583 [inline] #1: 00000000cee1b88f (sb_pagefaults){++++}, at: ext4_page_mkwrite+0x1d0/0x1430 fs/ext4/inode.c:6126 2 locks held by syz-executor5/11247: #0: 00000000d9fa3bcc (&mm->mmap_sem){++++}, at: __do_page_fault+0x389/0xe50 arch/x86/mm/fault.c:1325 #1: 00000000cee1b88f (sb_pagefaults){++++}, at: sb_start_pagefault include/linux/fs.h:1583 [inline] #1: 00000000cee1b88f (sb_pagefaults){++++}, at: ext4_page_mkwrite+0x1d0/0x1430 fs/ext4/inode.c:6126 2 locks held by syz-executor3/11259: #0: 00000000ce68675a (&mm->mmap_sem){++++}, at: __do_page_fault+0x389/0xe50 arch/x86/mm/fault.c:1325 #1: 00000000cee1b88f (sb_pagefaults){++++}, at: sb_start_pagefault include/linux/fs.h:1583 [inline] #1: 00000000cee1b88f (sb_pagefaults){++++}, at: ext4_page_mkwrite+0x1d0/0x1430 fs/ext4/inode.c:6126 2 locks held by syz-executor0/11263: #0: 000000004bc34bfe (&mm->mmap_sem){++++}, at: __do_page_fault+0x389/0xe50 arch/x86/mm/fault.c:1325 #1: 00000000cee1b88f (sb_pagefaults){++++}, at: sb_start_pagefault include/linux/fs.h:1583 [inline] #1: 00000000cee1b88f (sb_pagefaults){++++}, at: ext4_page_mkwrite+0x1d0/0x1430 fs/ext4/inode.c:6126 1 lock held by syz-executor0/11265: #0: 000000009ac828fd (sb_writers#6){++++}, at: sb_start_write include/linux/fs.h:1554 [inline] #0: 000000009ac828fd (sb_writers#6){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 902 Comm: khungtaskd Not tainted 4.18.0-rc4+ #138 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+0x1c9/0x2b4 lib/dump_stack.c:113 nmi_cpu_backtrace.cold.4+0x19/0xce lib/nmi_backtrace.c:103 nmi_trigger_cpumask_backtrace+0x151/0x192 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:138 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:196 [inline] watchdog+0x9c4/0xf80 kernel/hung_task.c:252 kthread+0x345/0x410 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:54