INFO: task khugepaged:908 blocked for more than 140 seconds. Not tainted 4.18.0-rc3+ #5 "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:2862 [inline] __schedule+0x87c/0x1ed0 kernel/sched/core.c:3504 schedule+0xfb/0x450 kernel/sched/core.c:3548 __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:240 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 INFO: task syz-fuzzer:4581 blocked for more than 140 seconds. Not tainted 4.18.0-rc3+ #5 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-fuzzer D19640 4581 4576 0x00000000 Call Trace: context_switch kernel/sched/core.c:2862 [inline] __schedule+0x87c/0x1ed0 kernel/sched/core.c:3504 schedule+0xfb/0x450 kernel/sched/core.c:3548 __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:6125 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:000000c421115538 EFLAGS: 00010212 RAX: 000000c421115878 RBX: 000000c421115880 RCX: 00007fed98d4e000 RDX: 0000000000000756 RSI: 0000000000000000 RDI: 0000000000000070 RBP: 000000c421115548 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000095bb32 R11: 0000000000000004 R12: 0000000000000000 R13: 0000000000000020 R14: 0000000000000013 R15: 000000c4211159e8 INFO: task syz-fuzzer:4584 blocked for more than 140 seconds. Not tainted 4.18.0-rc3+ #5 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-fuzzer D19624 4584 4576 0x00000000 Call Trace: context_switch kernel/sched/core.c:2862 [inline] __schedule+0x87c/0x1ed0 kernel/sched/core.c:3504 schedule+0xfb/0x450 kernel/sched/core.c:3548 __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:6125 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:000000c4217cd130 EFLAGS: 00010212 RAX: 000000c4217cd878 RBX: 000000c4217cd880 RCX: 00007fed97b4e000 RDX: fffffffffffffffe RSI: 0000000001f4a638 RDI: 000000c4217cd140 RBP: 000000c4217cd140 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000095bb32 R11: 0000000000000004 R12: 0000000000000000 R13: 0000000000000020 R14: 0000000000000013 R15: 000000c4217cd9e8 INFO: task syz-executor0:4603 blocked for more than 140 seconds. Not tainted 4.18.0-rc3+ #5 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D21232 4603 4595 0x00000000 Call Trace: context_switch kernel/sched/core.c:2862 [inline] __schedule+0x87c/0x1ed0 kernel/sched/core.c:3504 schedule+0xfb/0x450 kernel/sched/core.c:3548 __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 filename_create+0x13e/0x5b0 fs/namei.c:3640 user_path_create fs/namei.c:3703 [inline] do_mkdirat+0xda/0x310 fs/namei.c:3842 __do_sys_mkdir fs/namei.c:3866 [inline] __se_sys_mkdir fs/namei.c:3864 [inline] __x64_sys_mkdir+0x5c/0x80 fs/namei.c:3864 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x455267 Code: Bad RIP value. RSP: 002b:00007ffdeaa8eea8 EFLAGS: 00000202 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007ffdeaa8eed0 RCX: 0000000000455267 RDX: 00007ffdeaa8fb85 RSI: 00000000000001ff RDI: 00007ffdeaa8fb80 RBP: 0000000000000013 R08: 0000000000000000 R09: 0000000000000005 R10: 0000000000000064 R11: 0000000000000202 R12: 0000000000000000 R13: 0000000000001380 R14: 00007ffdeaa8f550 R15: 00000000007034c0 INFO: task syz-executor1:4605 blocked for more than 140 seconds. Not tainted 4.18.0-rc3+ #5 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor1 D21912 4605 4597 0x00000000 Call Trace: context_switch kernel/sched/core.c:2862 [inline] __schedule+0x87c/0x1ed0 kernel/sched/core.c:3504 schedule+0xfb/0x450 kernel/sched/core.c:3548 __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 filename_create+0x13e/0x5b0 fs/namei.c:3640 user_path_create fs/namei.c:3703 [inline] do_mkdirat+0xda/0x310 fs/namei.c:3842 __do_sys_mkdir fs/namei.c:3866 [inline] __se_sys_mkdir fs/namei.c:3864 [inline] __x64_sys_mkdir+0x5c/0x80 fs/namei.c:3864 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x455267 Code: Bad RIP value. RSP: 002b:00007ffeb775ccd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007ffeb775cd00 RCX: 0000000000455267 RDX: 00007ffeb775d9b5 RSI: 00000000000001ff RDI: 00007ffeb775d9b0 RBP: 0000000000000013 R08: 0000000000000000 R09: 0000000000000005 R10: 0000000000000064 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000001380 R14: 00007ffeb775d380 R15: 00000000007034c0 INFO: task syz-executor5:4606 blocked for more than 140 seconds. Not tainted 4.18.0-rc3+ #5 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor5 D20056 4606 4599 0x00000000 Call Trace: context_switch kernel/sched/core.c:2862 [inline] __schedule+0x87c/0x1ed0 kernel/sched/core.c:3504 schedule+0xfb/0x450 kernel/sched/core.c:3548 __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:00007ffd9b4cfe28 EFLAGS: 00000206 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000455b77 RDX: 00007ffd9b4cfe30 RSI: 00007ffd9b4cfec0 RDI: 00007ffd9b4cfec0 RBP: 00007ffd9b4d1bd0 R08: 0000000000000000 R09: 0000000000000010 R10: 000000000000000a R11: 0000000000000206 R12: 000000000132d940 R13: 0000000000000000 R14: 00007ffd9b4d15a0 R15: 0000000000702140 INFO: task syz-executor6:4607 blocked for more than 140 seconds. Not tainted 4.18.0-rc3+ #5 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor6 D22120 4607 4600 0x00000000 Call Trace: context_switch kernel/sched/core.c:2862 [inline] __schedule+0x87c/0x1ed0 kernel/sched/core.c:3504 schedule+0xfb/0x450 kernel/sched/core.c:3548 __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:00007fff057dc2c8 EFLAGS: 00000202 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000455b77 RDX: 00007fff057dc2d0 RSI: 00007fff057dc360 RDI: 00007fff057dc360 RBP: 00007fff057de070 R08: 0000000000000000 R09: 0000000000000010 R10: 000000000000000a R11: 0000000000000202 R12: 0000000002362940 R13: 0000000000000000 R14: 00007fff057dda40 R15: 0000000000702140 INFO: task syz-executor3:4609 blocked for more than 140 seconds. Not tainted 4.18.0-rc3+ #5 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D21232 4609 4602 0x00000000 Call Trace: context_switch kernel/sched/core.c:2862 [inline] __schedule+0x87c/0x1ed0 kernel/sched/core.c:3504 schedule+0xfb/0x450 kernel/sched/core.c:3548 __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:00007fffa05bcc28 EFLAGS: 00000206 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000455b77 RDX: 00007fffa05bcc30 RSI: 00007fffa05bccc0 RDI: 00007fffa05bccc0 RBP: 00007fffa05be9d0 R08: 0000000000000000 R09: 0000000000000010 R10: 000000000000000a R11: 0000000000000206 R12: 00000000024ae940 R13: 0000000000000000 R14: 00007fffa05be3a0 R15: 0000000000702140 INFO: task syz-executor4:15618 blocked for more than 140 seconds. Not tainted 4.18.0-rc3+ #5 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor4 D24640 15618 4608 0x00000004 Call Trace: context_switch kernel/sched/core.c:2862 [inline] __schedule+0x87c/0x1ed0 kernel/sched/core.c:3504 schedule+0xfb/0x450 kernel/sched/core.c:3548 __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:6125 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:00007ffda8b06020 EFLAGS: 00010283 RAX: 0000001b332206b0 RBX: 0000000000000000 RCX: 0000001b34220000 RDX: 0000001b332206b4 RSI: 0000000000730f88 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 00007ffda8b06060 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000002 R14: 000000000072bf48 R15: 000000000072bf48 INFO: task syz-executor2:15642 blocked for more than 140 seconds. Not tainted 4.18.0-rc3+ #5 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor2 D20136 15642 4604 0x00000004 Call Trace: context_switch kernel/sched/core.c:2862 [inline] __schedule+0x87c/0x1ed0 kernel/sched/core.c:3504 schedule+0xfb/0x450 kernel/sched/core.c:3548 __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:6125 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:00007fffb1ae7470 EFLAGS: 00010287 RAX: 0000001b330215ac RBX: 0000000000000000 RCX: 0000001b34020000 RDX: 0000001b330215b0 RSI: 00000000007313a8 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 00007fffb1ae74b0 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000002 R14: 000000000072bea0 R15: 000000000072bea0 Showing all locks held in the system: 1 lock held by khungtaskd/902: #0: 000000002533f27b (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x428 kernel/locking/lockdep.c:4461 1 lock held by khugepaged/908: #0: 00000000360e0a63 (&mm->mmap_sem){++++}, at: collapse_huge_page+0x2b9/0x2140 mm/khugepaged.c:1006 2 locks held by rs:main Q:Reg/4464: #0: 00000000f16c7fd6 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 #1: 000000001db3e19c (sb_writers#6){++++}, at: file_start_write include/linux/fs.h:2737 [inline] #1: 000000001db3e19c (sb_writers#6){++++}, at: vfs_write+0x452/0x560 fs/read_write.c:548 1 lock held by rsyslogd/4466: 2 locks held by getty/4557: #0: 000000009df88dcc (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000ff3c1f22 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4558: #0: 0000000045430525 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000001268406e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4559: #0: 00000000fbe78154 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000c11b680e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4560: #0: 000000000abeb7a3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000ba84e032 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4561: #0: 00000000f148a3c2 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000311142e9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4562: #0: 000000004abf878f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000016504e4d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4563: #0: 0000000032b03327 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000009cc9b36f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by syz-fuzzer/4581: #0: 00000000360e0a63 (&mm->mmap_sem){++++}, at: __do_page_fault+0x389/0xe50 arch/x86/mm/fault.c:1325 #1: 000000005bdc7f2a (sb_pagefaults){++++}, at: sb_start_pagefault include/linux/fs.h:1583 [inline] #1: 000000005bdc7f2a (sb_pagefaults){++++}, at: ext4_page_mkwrite+0x1d0/0x1430 fs/ext4/inode.c:6125 2 locks held by syz-fuzzer/4584: #0: 00000000360e0a63 (&mm->mmap_sem){++++}, at: __do_page_fault+0x389/0xe50 arch/x86/mm/fault.c:1325 #1: 000000005bdc7f2a (sb_pagefaults){++++}, at: sb_start_pagefault include/linux/fs.h:1583 [inline] #1: 000000005bdc7f2a (sb_pagefaults){++++}, at: ext4_page_mkwrite+0x1d0/0x1430 fs/ext4/inode.c:6125 1 lock held by syz-executor0/4603: #0: 000000001db3e19c (sb_writers#6){++++}, at: sb_start_write include/linux/fs.h:1554 [inline] #0: 000000001db3e19c (sb_writers#6){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 1 lock held by syz-executor1/4605: #0: 000000001db3e19c (sb_writers#6){++++}, at: sb_start_write include/linux/fs.h:1554 [inline] #0: 000000001db3e19c (sb_writers#6){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 1 lock held by syz-executor5/4606: #0: 000000001db3e19c (sb_writers#6){++++}, at: sb_start_write include/linux/fs.h:1554 [inline] #0: 000000001db3e19c (sb_writers#6){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 1 lock held by syz-executor6/4607: #0: 000000001db3e19c (sb_writers#6){++++}, at: sb_start_write include/linux/fs.h:1554 [inline] #0: 000000001db3e19c (sb_writers#6){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 1 lock held by syz-executor3/4609: #0: 000000001db3e19c (sb_writers#6){++++}, at: sb_start_write include/linux/fs.h:1554 [inline] #0: 000000001db3e19c (sb_writers#6){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 2 locks held by syz-executor4/15618: #0: 000000007b5cc617 (&mm->mmap_sem){++++}, at: __do_page_fault+0x389/0xe50 arch/x86/mm/fault.c:1325 #1: 000000005bdc7f2a (sb_pagefaults){++++}, at: sb_start_pagefault include/linux/fs.h:1583 [inline] #1: 000000005bdc7f2a (sb_pagefaults){++++}, at: ext4_page_mkwrite+0x1d0/0x1430 fs/ext4/inode.c:6125 2 locks held by syz-executor2/15642: #0: 0000000055762920 (&mm->mmap_sem){++++}, at: __do_page_fault+0x389/0xe50 arch/x86/mm/fault.c:1325 #1: 000000005bdc7f2a (sb_pagefaults){++++}, at: sb_start_pagefault include/linux/fs.h:1583 [inline] #1: 000000005bdc7f2a (sb_pagefaults){++++}, at: ext4_page_mkwrite+0x1d0/0x1430 fs/ext4/inode.c:6125 2 locks held by syz-executor7/15648: #0: 0000000057fca37d (&mm->mmap_sem){++++}, at: __do_page_fault+0x389/0xe50 arch/x86/mm/fault.c:1325 #1: 000000005bdc7f2a (sb_pagefaults){++++}, at: sb_start_pagefault include/linux/fs.h:1583 [inline] #1: 000000005bdc7f2a (sb_pagefaults){++++}, at: ext4_page_mkwrite+0x1d0/0x1430 fs/ext4/inode.c:6125 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 902 Comm: khungtaskd Not tainted 4.18.0-rc3+ #5 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:240 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 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:54