Comment 8 for bug 1424342

Call trace from Ubuntu 16.04 and cifs-utils 2:6.4-1ubuntu1.1 on 4.10.0-42-generic:

[19936.692679] INFO: task ls:15421 blocked for more than 120 seconds.
[19936.692683] Tainted: G W 4.10.0-42-generic #46~16.04.1-Ubuntu
[19936.692685] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[19936.692687] ls D 0 15421 15411 0x00000000
[19936.692691] Call Trace:
[19936.692694] __schedule+0x232/0x700
[19936.692698] schedule+0x36/0x80
[19936.692701] schedule_preempt_disabled+0xe/0x10
[19936.692704] __mutex_lock_slowpath+0x193/0x290
[19936.692708] mutex_lock+0x2f/0x40
[19936.692728] cifs_reconnect_tcon+0x95/0x340 [cifs]
[19936.692733] ? __find_get_block+0x22c/0x260
[19936.692736] ? __check_block_validity.constprop.75+0x31/0x70
[19936.692756] smb_init+0x2a/0x50 [cifs]
[19936.692777] CIFSSMBQPathInfo+0x63/0x2e0 [cifs]
[19936.692805] cifs_query_path_info+0x6f/0x1a0 [cifs]
[19936.692809] ? __kmalloc+0x1c7/0x200
[19936.692812] ? ext4_htree_store_dirent+0x3e/0x120
[19936.692816] ? lookup_fast+0xe3/0x2f0
[19936.692819] ? kmem_cache_alloc_trace+0x152/0x1c0
[19936.692844] cifs_get_inode_info+0x4a3/0x970 [cifs]
[19936.692847] ? unlazy_walk+0xf8/0x180
[19936.692851] ? __kmalloc+0x178/0x200
[19936.692874] ? build_path_from_dentry+0xe2/0x3e0 [cifs]
[19936.692895] ? build_path_from_dentry+0xe2/0x3e0 [cifs]
[19936.692918] cifs_revalidate_dentry_attr+0x1d5/0x250 [cifs]
[19936.692941] cifs_getattr+0x51/0x110 [cifs]
[19936.692946] vfs_getattr_nosec+0x29/0x40
[19936.692949] vfs_getattr+0x26/0x30
[19936.692953] vfs_fstatat+0x78/0xc0
[19936.692958] SYSC_newlstat+0x31/0x60
[19936.692963] SyS_newlstat+0xe/0x10
[19936.692967] entry_SYSCALL_64_fastpath+0x1e/0xad
[19936.692969] RIP: 0033:0x7f927b0afc55
[19936.692971] RSP: 002b:00007ffc7a297c98 EFLAGS: 00000246 ORIG_RAX: 0000000000000006
[19936.692974] RAX: ffffffffffffffda RBX: 00007f927b37db20 RCX: 00007f927b0afc55
[19936.692975] RDX: 000000000159ed60 RSI: 000000000159ed60 RDI: 00007ffc7a297ca0
[19936.692977] RBP: 0000000000008041 R08: 0000000000000000 R09: 00000000000003c0
[19936.692978] R10: 00000000000001cc R11: 0000000000000246 R12: 00007f927b37db78
[19936.692980] R13: 00007f927b37db78 R14: 0000000000002710 R15: 0000000000404ad0