kworker/dying (58) used greatest stack depth: 12776 bytes left INFO: task syz-executor0:4597 blocked for more than 140 seconds. Not tainted 4.18.0-rc4+ #142 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D21232 4597 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: c0 48 89 44 24 30 48 8b 2c 24 48 83 c4 08 c3 89 74 24 28 48 83 c0 02 48 89 44 24 30 48 8b 2c 24 48 83 c4 08 c3 8d 7e 20 40 80 10 73 64 48 83 fa 02 7e c2 0f b6 54 0b 01 8d 7a 80 40 80 ff 3f RSP: 002b:00007ffec3f0f9e8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000455b77 RDX: 00007ffec3f0f9f0 RSI: 00007ffec3f0fa80 RDI: 00007ffec3f0fa80 RBP: 00007ffec3f11790 R08: 0000000000000000 R09: 0000000000000010 R10: 000000000000000a R11: 0000000000000206 R12: 00000000025b2940 R13: 0000000000000000 R14: 00007ffec3f11160 R15: 0000000000702140 INFO: task syz-executor1:4598 blocked for more than 140 seconds. Not tainted 4.18.0-rc4+ #142 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor1 D21208 4598 4591 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: c0 48 89 44 24 30 48 8b 2c 24 48 83 c4 08 c3 89 74 24 28 48 83 c0 02 48 89 44 24 30 48 8b 2c 24 48 83 c4 08 c3 8d 7e 20 40 80 10 73 64 48 83 fa 02 7e c2 0f b6 54 0b 01 8d 7a 80 40 80 ff 3f RSP: 002b:00007ffd318b0608 EFLAGS: 00000202 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000455b77 RDX: 00007ffd318b0610 RSI: 00007ffd318b06a0 RDI: 00007ffd318b06a0 RBP: 00007ffd318b23b0 R08: 0000000000000000 R09: 0000000000000010 R10: 000000000000000a R11: 0000000000000202 R12: 0000000000fed940 R13: 0000000000000000 R14: 00007ffd318b1d80 R15: 0000000000702140 INFO: task syz-executor6:15938 blocked for more than 140 seconds. Not tainted 4.18.0-rc4+ #142 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor6 D24696 15938 4602 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: 24 1f e9 d2 00 00 00 48 ff c2 48 83 fa 08 0f 83 ad 00 00 00 84 01 0f b6 1c 11 38 d8 75 e9 48 89 54 24 20 48 8b 5c 24 48 0f b6 <73> 50 48 0f af f2 0f b6 5b 51 48 89 cf 48 8d 74 3e 08 84 db 74 7c RSP: 002b:00007fffb942a3c0 EFLAGS: 00010287 RAX: 0000001b32d219a0 RBX: 0000000000000000 RCX: 0000001b33d20000 RDX: 0000001b32d219a4 RSI: 00000000007306c0 RDI: 0000000000000005 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 00007fffb942a400 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000002 R14: 000000000072bf48 R15: 000000000072bf48 INFO: task syz-executor7:15944 blocked for more than 140 seconds. Not tainted 4.18.0-rc4+ #142 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor7 D24696 15944 4596 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: 24 1f e9 d2 00 00 00 48 ff c2 48 83 fa 08 0f 83 ad 00 00 00 84 01 0f b6 1c 11 38 d8 75 e9 48 89 54 24 20 48 8b 5c 24 48 0f b6 <73> 50 48 0f af f2 0f b6 5b 51 48 89 cf 48 8d 74 3e 08 84 db 74 7c RSP: 002b:00007ffd9f3e9b00 EFLAGS: 00010287 RAX: 0000001b3292530c RBX: 0000000000000000 RCX: 0000001b33920000 RDX: 0000001b32925310 RSI: 0000000000730470 RDI: 0000000000000005 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 00007ffd9f3e9b40 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000002 R14: 000000000072bea0 R15: 000000000072bea0 INFO: task syz-executor3:15962 blocked for more than 140 seconds. Not tainted 4.18.0-rc4+ #142 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D24696 15962 4603 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: 24 1f e9 d2 00 00 00 48 ff c2 48 83 fa 08 0f 83 ad 00 00 00 84 01 0f b6 1c 11 38 d8 75 e9 48 89 54 24 20 48 8b 5c 24 48 0f b6 <73> 50 48 0f af f2 0f b6 5b 51 48 89 cf 48 8d 74 3e 08 84 db 74 7c RSP: 002b:00007fffe553d0c0 EFLAGS: 00010287 RAX: 0000001b32f21a5c RBX: 0000000000000000 RCX: 0000001b33f20000 RDX: 0000001b32f21a60 RSI: 0000000000000005 RDI: 0000000000000005 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 00007fffe553d100 R11: 0000000000000246 R12: 0000000000000009 R13: 0000000000000002 R14: 000000000072bf48 R15: 000000000072bf48 INFO: task syz-executor4:15965 blocked for more than 140 seconds. Not tainted 4.18.0-rc4+ #142 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor4 D24696 15965 4599 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: 24 1f e9 d2 00 00 00 48 ff c2 48 83 fa 08 0f 83 ad 00 00 00 84 01 0f b6 1c 11 38 d8 75 e9 48 89 54 24 20 48 8b 5c 24 48 0f b6 <73> 50 48 0f af f2 0f b6 5b 51 48 89 cf 48 8d 74 3e 08 84 db 74 7c RSP: 002b:00007ffe6223fb10 EFLAGS: 00010283 RAX: 0000001b32a20db0 RBX: 0000000000000000 RCX: 0000001b33a20000 RDX: 0000001b32a20db4 RSI: 0000000000730128 RDI: 0000000000000001 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 00007ffe6223fb50 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000002 R14: 000000000072bea0 R15: 000000000072bea0 INFO: task syz-executor5:15976 blocked for more than 140 seconds. Not tainted 4.18.0-rc4+ #142 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor5 D26296 15976 4601 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_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_symlinkat+0xfe/0x2d0 fs/namei.c:4157 __do_sys_symlink fs/namei.c:4183 [inline] __se_sys_symlink fs/namei.c:4181 [inline] __x64_sys_symlink+0x59/0x80 fs/namei.c:4181 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x455b57 Code: 80 80 fa 3f 77 10 83 e6 1f c1 e6 06 83 e1 3f 09 ce 83 fe 7f 7f 19 c7 44 24 28 fd ff 00 00 48 ff c0 48 89 44 24 30 48 8b 2c 24 <48> 83 c4 08 c3 89 74 24 28 48 83 c0 02 48 89 44 24 30 48 8b 2c 24 RSP: 002b:00007fff93544a38 EFLAGS: 00000217 ORIG_RAX: 0000000000000058 RAX: ffffffffffffffda RBX: 0000000000000013 RCX: 0000000000455b57 RDX: 0000000000000000 RSI: 00000000004bb371 RDI: 00007fff93545730 RBP: 0000000000000013 R08: 0000000000000000 R09: 0000000000ee2940 R10: 0000000000000000 R11: 0000000000000217 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fff935450e0 R15: 00000000007034c0 INFO: task syz-executor2:15977 blocked for more than 140 seconds. Not tainted 4.18.0-rc4+ #142 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor2 D26296 15977 4600 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_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_symlinkat+0xfe/0x2d0 fs/namei.c:4157 __do_sys_symlink fs/namei.c:4183 [inline] __se_sys_symlink fs/namei.c:4181 [inline] __x64_sys_symlink+0x59/0x80 fs/namei.c:4181 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x455b57 Code: 80 80 fa 3f 77 10 83 e6 1f c1 e6 06 83 e1 3f 09 ce 83 fe 7f 7f 19 c7 44 24 28 fd ff 00 00 48 ff c0 48 89 44 24 30 48 8b 2c 24 <48> 83 c4 08 c3 89 74 24 28 48 83 c0 02 48 89 44 24 30 48 8b 2c 24 RSP: 002b:00007ffdaba8ede8 EFLAGS: 00000217 ORIG_RAX: 0000000000000058 RAX: ffffffffffffffda RBX: 0000000000000013 RCX: 0000000000455b57 RDX: 0000000000000000 RSI: 00000000004bb371 RDI: 00007ffdaba8fae0 RBP: 0000000000000013 R08: 0000000000000000 R09: 00000000016e3940 R10: 0000000000000000 R11: 0000000000000217 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ffdaba8f490 R15: 00000000007034c0 Showing all locks held in the system: 1 lock held by khungtaskd/897: #0: 0000000072d9a3e5 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x428 kernel/locking/lockdep.c:4461 2 locks held by rs:main Q:Reg/4455: #0: 00000000656ae79d (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 #1: 00000000e76d92bc (sb_writers#6){++++}, at: file_start_write include/linux/fs.h:2737 [inline] #1: 00000000e76d92bc (sb_writers#6){++++}, at: vfs_write+0x452/0x560 fs/read_write.c:548 1 lock held by rsyslogd/4457: #0: 0000000048535a21 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 2 locks held by getty/4547: #0: 00000000c32b6b95 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000b53ec945 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4548: #0: 00000000672ea175 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000942dc25a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4549: #0: 000000003713d823 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000008aed517d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4550: #0: 0000000058215eaa (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000b0e2d894 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4551: #0: 00000000bb6cc5a5 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000092bcb092 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4552: #0: 000000006ac8bb6d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000007cd44af3 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4553: #0: 000000006f67ea37 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000019f9076f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 1 lock held by syz-executor0/4597: #0: 00000000e76d92bc (sb_writers#6){++++}, at: sb_start_write include/linux/fs.h:1554 [inline] #0: 00000000e76d92bc (sb_writers#6){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 1 lock held by syz-executor1/4598: #0: 00000000e76d92bc (sb_writers#6){++++}, at: sb_start_write include/linux/fs.h:1554 [inline] #0: 00000000e76d92bc (sb_writers#6){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 2 locks held by syz-executor6/15938: #0: 000000005a244f59 (&mm->mmap_sem){++++}, at: __do_page_fault+0x389/0xe50 arch/x86/mm/fault.c:1325 #1: 00000000a3aa1b19 (sb_pagefaults){++++}, at: sb_start_pagefault include/linux/fs.h:1583 [inline] #1: 00000000a3aa1b19 (sb_pagefaults){++++}, at: ext4_page_mkwrite+0x1d0/0x1430 fs/ext4/inode.c:6126 2 locks held by syz-executor7/15944: #0: 0000000060e4bdd6 (&mm->mmap_sem){++++}, at: __do_page_fault+0x389/0xe50 arch/x86/mm/fault.c:1325 #1: 00000000a3aa1b19 (sb_pagefaults){++++}, at: sb_start_pagefault include/linux/fs.h:1583 [inline] #1: 00000000a3aa1b19 (sb_pagefaults){++++}, at: ext4_page_mkwrite+0x1d0/0x1430 fs/ext4/inode.c:6126 2 locks held by syz-executor3/15962: #0: 00000000c35ade3c (&mm->mmap_sem){++++}, at: __do_page_fault+0x389/0xe50 arch/x86/mm/fault.c:1325 #1: 00000000a3aa1b19 (sb_pagefaults){++++}, at: sb_start_pagefault include/linux/fs.h:1583 [inline] #1: 00000000a3aa1b19 (sb_pagefaults){++++}, at: ext4_page_mkwrite+0x1d0/0x1430 fs/ext4/inode.c:6126 2 locks held by syz-executor4/15965: #0: 00000000fe629c03 (&mm->mmap_sem){++++}, at: __do_page_fault+0x389/0xe50 arch/x86/mm/fault.c:1325 #1: 00000000a3aa1b19 (sb_pagefaults){++++}, at: sb_start_pagefault include/linux/fs.h:1583 [inline] #1: 00000000a3aa1b19 (sb_pagefaults){++++}, at: ext4_page_mkwrite+0x1d0/0x1430 fs/ext4/inode.c:6126 1 lock held by syz-executor5/15976: #0: 00000000e76d92bc (sb_writers#6){++++}, at: sb_start_write include/linux/fs.h:1554 [inline] #0: 00000000e76d92bc (sb_writers#6){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 1 lock held by syz-executor2/15977: #0: 00000000e76d92bc (sb_writers#6){++++}, at: sb_start_write include/linux/fs.h:1554 [inline] #0: 00000000e76d92bc (sb_writers#6){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 1 lock held by cron/15980: #0: 00000000e76d92bc (sb_writers#6){++++}, at: sb_start_write include/linux/fs.h:1554 [inline] #0: 00000000e76d92bc (sb_writers#6){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 897 Comm: khungtaskd Not tainted 4.18.0-rc4+ #142 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 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.18.0-rc4+ #142 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:trace_softirqs_off+0x1fd/0x380 kernel/locking/lockdep.c:3006 Code: 08 84 c0 0f 85 68 01 00 00 8b 15 3e a9 45 09 85 d2 75 10 65 8b 05 a3 cb a2 7e f6 c4 ff 0f 84 a9 00 00 00 5b 41 5c 41 5d 5d c3 <48> c7 c7 60 b0 f1 88 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 RSP: 0018:ffff8801dae07c88 EFLAGS: 00000046 RAX: 0000000000000003 RBX: ffffffff88e75dc0 RCX: 1ffff1003b5c46d5 RDX: 0000000000000004 RSI: 0000000080000001 RDI: 0000000000000000 RBP: ffff8801dae07ca0 R08: 0000000000000000 R09: 0000000000000001 R10: ffffed003b5c46d6 R11: ffff8801dae236b3 R12: ffffffff8aa4cb60 R13: ffffffff81491bf0 R14: ffff8801dae07e68 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000020740f8 CR3: 00000001b1db6000 CR4: 00000000001426f0 DR0: 000000000000000b DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __local_bh_disable_ip+0xe9/0x120 kernel/softirq.c:125 local_bh_disable include/linux/bottom_half.h:19 [inline] irq_enter+0xb1/0xd0 kernel/softirq.c:348 scheduler_ipi+0x3a9/0xa50 kernel/sched/core.c:1790 smp_reschedule_interrupt+0xf5/0x670 arch/x86/kernel/smp.c:277 reschedule_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:887 RIP: 0010:native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:54 Code: c7 48 89 45 d8 e8 0a 00 26 fa 48 8b 45 d8 e9 d2 fe ff ff 48 89 df e8 f9 ff 25 fa eb 8a 90 90 90 90 90 90 90 55 48 89 e5 fb f4 <5d> c3 0f 1f 84 00 00 00 00 00 55 48 89 e5 f4 5d c3 90 90 90 90 90 RSP: 0018:ffffffff88e07bc0 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff02 RAX: dffffc0000000000 RBX: 1ffffffff11c0f7b RCX: 0000000000000000 RDX: 1ffffffff11e3610 RSI: 0000000000000001 RDI: ffffffff88f1b080 RBP: ffffffff88e07bc0 R08: ffffed003b5c46d7 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffffffff88e07c78 R14: ffffffff899ed060 R15: 0000000000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline] default_idle+0xc7/0x450 arch/x86/kernel/process.c:500 arch_cpu_idle+0x10/0x20 arch/x86/kernel/process.c:491 default_idle_call+0x6d/0x90 kernel/sched/idle.c:93 cpuidle_idle_call kernel/sched/idle.c:153 [inline] do_idle+0x3aa/0x570 kernel/sched/idle.c:262 cpu_startup_entry+0x10c/0x120 kernel/sched/idle.c:368 rest_init+0xe1/0xe4 init/main.c:442 start_kernel+0x90e/0x949 init/main.c:738 x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:452 x86_64_start_kernel+0x76/0x79 arch/x86/kernel/head64.c:433 secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:242