INFO: task syz-executor.3:28160 can't die for more than 143 seconds. task:syz-executor.3 state:D stack:27648 pid:28160 ppid: 8486 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x8cd/0x2150 kernel/sched/core.c:5078 schedule+0xcf/0x270 kernel/sched/core.c:5157 rwsem_down_write_slowpath+0x7e5/0x1200 kernel/locking/rwsem.c:1106 __down_write_common kernel/locking/rwsem.c:1261 [inline] __down_write_common kernel/locking/rwsem.c:1258 [inline] __down_write kernel/locking/rwsem.c:1270 [inline] down_write+0x132/0x150 kernel/locking/rwsem.c:1407 inode_lock include/linux/fs.h:773 [inline] lock_mount+0x8a/0x2e0 fs/namespace.c:2214 do_new_mount_fc fs/namespace.c:2842 [inline] do_new_mount fs/namespace.c:2901 [inline] path_mount+0x1678/0x1e70 fs/namespace.c:3230 do_mount fs/namespace.c:3243 [inline] __do_sys_mount fs/namespace.c:3451 [inline] __se_sys_mount fs/namespace.c:3428 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3428 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e219 RSP: 002b:00007fce19502c68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000045e219 RDX: 0000000020002100 RSI: 00000000200020c0 RDI: 0000000000000000 RBP: 000000000119bfd0 R08: 0000000020002140 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c R13: 00007fff8157315f R14: 00007fce195039c0 R15: 000000000119bf8c INFO: task syz-executor.3:28160 blocked for more than 143 seconds. Not tainted 5.10.0-next-20201223-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.3 state:D stack:27648 pid:28160 ppid: 8486 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x8cd/0x2150 kernel/sched/core.c:5078 schedule+0xcf/0x270 kernel/sched/core.c:5157 rwsem_down_write_slowpath+0x7e5/0x1200 kernel/locking/rwsem.c:1106 __down_write_common kernel/locking/rwsem.c:1261 [inline] __down_write_common kernel/locking/rwsem.c:1258 [inline] __down_write kernel/locking/rwsem.c:1270 [inline] down_write+0x132/0x150 kernel/locking/rwsem.c:1407 inode_lock include/linux/fs.h:773 [inline] lock_mount+0x8a/0x2e0 fs/namespace.c:2214 do_new_mount_fc fs/namespace.c:2842 [inline] do_new_mount fs/namespace.c:2901 [inline] path_mount+0x1678/0x1e70 fs/namespace.c:3230 do_mount fs/namespace.c:3243 [inline] __do_sys_mount fs/namespace.c:3451 [inline] __se_sys_mount fs/namespace.c:3428 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3428 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e219 RSP: 002b:00007fce19502c68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000045e219 RDX: 0000000020002100 RSI: 00000000200020c0 RDI: 0000000000000000 RBP: 000000000119bfd0 R08: 0000000020002140 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c R13: 00007fff8157315f R14: 00007fce195039c0 R15: 000000000119bf8c INFO: task syz-executor.3:28167 can't die for more than 144 seconds. task:syz-executor.3 state:R running task stack:25592 pid:28167 ppid: 8486 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x8cd/0x2150 kernel/sched/core.c:5078 Showing all locks held in the system: 1 lock held by khungtaskd/1659: #0: ffffffff8b363660 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6254 3 locks held by kworker/u4:5/3110: 1 lock held by systemd-journal/4891: 1 lock held by in:imklog/8169: #0: ffff88801b30f4f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:949 2 locks held by rs:main Q:Reg/8170: #0: ffff8880116054f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:949 #1: ffff8881476aa460 (sb_writers#4){.+.+}-{0:0}, at: ksys_write+0x12d/0x250 fs/read_write.c:658 1 lock held by syz-executor.3/28160: #0: ffff88802e848810 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:773 [inline] #0: ffff88802e848810 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: lock_mount+0x8a/0x2e0 fs/namespace.c:2214 3 locks held by syz-executor.3/28167: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1659 Comm: khungtaskd Not tainted 5.10.0-next-20201223-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:147 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:253 [inline] watchdog+0xd89/0xf30 kernel/hung_task.c:338 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 4891 Comm: systemd-journal Not tainted 5.10.0-next-20201223-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:lock_release+0x4a/0x710 kernel/locking/lockdep.c:5445 Code: 6c 24 10 48 89 74 24 08 48 c7 44 24 10 b3 8a b5 41 48 c1 ed 03 48 c7 44 24 18 18 f5 c6 8a 48 01 e8 48 c7 44 24 20 90 8d 58 81 00 f1 f1 f1 f1 c7 40 04 f1 f1 04 f2 c7 40 08 04 f3 f3 f3 65 48 RSP: 0018:ffffc90000007d50 EFLAGS: 00000086 RAX: fffff52000000fac RBX: ffffffff8149dcf0 RCX: 0000000000000100 RDX: ffff888011683800 RSI: ffffffff81621706 RDI: ffff8880b9e24898 RBP: 1ffff92000000fac R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff816218c6 R11: 0000000000000000 R12: ffff8880b9e24898 R13: 0000000000200000 R14: dffffc0000000000 R15: ffff8880b9e24880 FS: 00007f824b0c78c0(0000) GS:ffff8880b9e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8248753020 CR3: 00000000260bd000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_unlock include/linux/spinlock_api_smp.h:150 [inline] _raw_spin_unlock+0x12/0x40 kernel/locking/spinlock.c:183 expire_timers kernel/time/timer.c:1456 [inline] __run_timers.part.0+0x496/0xa50 kernel/time/timer.c:1731 __run_timers kernel/time/timer.c:1712 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1744 __do_softirq+0x2a5/0x9f7 kernel/softirq.c:343 asm_call_irq_on_stack+0xf/0x20 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline] do_softirq_own_stack+0xaa/0xd0 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:226 [inline] __irq_exit_rcu kernel/softirq.c:420 [inline] irq_exit_rcu+0x134/0x200 kernel/softirq.c:432 sysvec_apic_timer_interrupt+0x4d/0x100 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:628 RIP: 0010:devkmsg_read+0x3da/0x740 kernel/printk/printk.c:754 Code: 01 80 3c 02 00 0f 85 19 03 00 00 48 c7 c7 00 47 35 8b 4c 89 6d 00 e8 45 1a 94 07 e8 d0 48 00 00 e8 2b 62 1d 00 fb 48 8b 2c 24 <4c> 89 ff 48 c7 c3 ea ff ff ff 48 89 ee e8 d4 95 17 00 49 39 ef 77 RSP: 0018:ffffc9000164fd68 EFLAGS: 00000206 RAX: 0000000000317fff RBX: ffff8880265220f8 RCX: ffffffff815811c7 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000002000 R08: 0000000000000001 R09: ffffffff8ebe284f R10: fffffbfff1d7c509 R11: 000000000000005c R12: 1ffff920002c9fb2 R13: 0000000000001b94 R14: ffff888026520068 R15: 000000000000002d vfs_read+0x1b5/0x570 fs/read_write.c:494 ksys_read+0x12d/0x250 fs/read_write.c:634 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f824a657210 Code: 73 01 c3 48 8b 0d 98 7d 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d b9 c1 20 00 00 75 10 b8 00 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 4e fc ff ff 48 89 04 24 RSP: 002b:00007ffdac19a268 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007ffdac19cce0 RCX: 00007f824a657210 RDX: 0000000000002000 RSI: 00007ffdac19aae0 RDI: 0000000000000009 RBP: 0000000000000000 R08: 0000000000000008 R09: 0000562794b447b8 R10: 0000562794b44780 R11: 0000000000000246 R12: 00007ffdac19aae0 R13: 00007ffdac19cc38 R14: 0000562794065958 R15: 0005b7cc3382a5e8