INFO: task syz-executor3:15868 blocked for more than 140 seconds. Not tainted 4.19.0-rc6+ #271 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D24720 15868 5874 0x00000004 Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473 schedule+0xfe/0x460 kernel/sched/core.c:3517 d_wait_lookup fs/dcache.c:2428 [inline] d_alloc_parallel+0x1474/0x1f40 fs/dcache.c:2510 __lookup_slow+0x1e6/0x540 fs/namei.c:1654 lookup_slow+0x57/0x80 fs/namei.c:1688 walk_component+0x92b/0x25c0 fs/namei.c:1810 lookup_last fs/namei.c:2273 [inline] path_lookupat.isra.43+0x212/0xc00 fs/namei.c:2318 filename_lookup+0x26a/0x520 fs/namei.c:2348 user_path_at_empty+0x40/0x50 fs/namei.c:2608 user_path_at include/linux/namei.h:57 [inline] vfs_statx+0x129/0x210 fs/stat.c:185 vfs_lstat include/linux/fs.h:3118 [inline] __do_sys_newlstat+0x8f/0x110 fs/stat.c:350 __se_sys_newlstat fs/stat.c:344 [inline] __x64_sys_newlstat+0x54/0x80 fs/stat.c:344 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457579 Code: Bad RIP value. RSP: 002b:00007fee93ed9c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000006 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000457579 RDX: 0000000000000000 RSI: 0000000020000b00 RDI: 0000000020000a40 RBP: 000000000072c040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fee93eda6d4 R13: 00000000004c27ae R14: 00000000004d3a38 R15: 00000000ffffffff INFO: task syz-executor3:15870 blocked for more than 140 seconds. Not tainted 4.19.0-rc6+ #271 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D23864 15870 5874 0x00000004 Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473 schedule+0xfe/0x460 kernel/sched/core.c:3517 __rwsem_down_write_failed_common+0xbb9/0x1670 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+0xa5/0x130 kernel/locking/rwsem.c:72 inode_lock include/linux/fs.h:738 [inline] lock_mount+0x8c/0x2e0 fs/namespace.c:2027 do_add_mount+0x27/0x370 fs/namespace.c:2404 do_new_mount fs/namespace.c:2471 [inline] do_mount+0x19cd/0x31f0 fs/namespace.c:2787 ksys_mount+0x12d/0x140 fs/namespace.c:3003 __do_sys_mount fs/namespace.c:3017 [inline] __se_sys_mount fs/namespace.c:3014 [inline] __x64_sys_mount+0xbe/0x150 fs/namespace.c:3014 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457579 Code: Bad RIP value. RSP: 002b:00007fee93eb8c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000457579 RDX: 0000000020000900 RSI: 0000000020000000 RDI: 0000000000000000 RBP: 000000000072c0e0 R08: 0000000020000840 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fee93eb96d4 R13: 00000000004c28b5 R14: 00000000004d3c90 R15: 00000000ffffffff INFO: lockdep is turned off. NMI backtrace for cpu 0 CPU: 0 PID: 982 Comm: khungtaskd Not tainted 4.19.0-rc6+ #271 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+0x1c4/0x2b4 lib/dump_stack.c:113 nmi_cpu_backtrace.cold.3+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x1ed 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:144 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline] watchdog+0xb3e/0x1050 kernel/hung_task.c:265 kthread+0x35a/0x420 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 3195 Comm: udevd Not tainted 4.19.0-rc6+ #271 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:ep_send_events_proc+0xea/0xed0 fs/eventpoll.c:1626 Code: c7 40 30 f2 f2 f2 f2 c7 40 34 00 f2 f2 f2 c7 40 38 f2 f2 f2 f2 c7 40 3c 00 f2 f2 f2 c7 40 40 f2 f2 f2 f2 c7 40 44 00 f2 f2 f2 <65> 48 8b 04 25 28 00 00 00 48 89 45 d0 31 c0 e8 c2 fb 99 ff 48 8d RSP: 0018:ffff8801c8327360 EFLAGS: 00000282 RAX: ffffed0039064e7a RBX: dffffc0000000000 RCX: 0000000000000000 RDX: ffff8801c8327b28 RSI: ffff8801c83276e8 RDI: ffff8801c7e6f540 RBP: ffff8801c8327658 R08: ffff8801c8318180 R09: ffffed0038fcdeb8 R10: ffffed0038fcdeb8 R11: ffff8801c7e6f5c3 R12: ffff8801c8327968 R13: ffff8801c8327630 R14: ffff8801c7e6f5c0 R15: ffff8801c7e6f540 FS: 00007f5e6a64b7a0(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001c815d000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ep_scan_ready_list+0x4bd/0x1050 fs/eventpoll.c:708 ep_send_events fs/eventpoll.c:1713 [inline] ep_poll+0x572/0x13d0 fs/eventpoll.c:1840 do_epoll_wait+0x1b0/0x200 fs/eventpoll.c:2198 __do_sys_epoll_wait fs/eventpoll.c:2208 [inline] __se_sys_epoll_wait fs/eventpoll.c:2205 [inline] __x64_sys_epoll_wait+0x97/0xf0 fs/eventpoll.c:2205 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f5e69d5f943 Code: 00 31 d2 48 29 c2 64 89 11 48 83 c8 ff eb ea 90 90 90 90 90 90 90 90 83 3d b5 dc 2a 00 00 75 13 49 89 ca b8 e8 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 34 c3 48 83 ec 08 e8 3b c4 00 00 48 89 04 24 RSP: 002b:00007ffd807f1908 EFLAGS: 00000246 ORIG_RAX: 00000000000000e8 RAX: ffffffffffffffda RBX: 0000000000000bb8 RCX: 00007f5e69d5f943 RDX: 0000000000000008 RSI: 00007ffd807f1a00 RDI: 000000000000000a RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000bb8 R11: 0000000000000246 R12: 0000000000000003 R13: 0000000000000000 R14: 00000000009430b0 R15: 000000000093d250