NFS server hangs frequently or crashing with a reboot and NFS server shows "nfsd: non-standard errno: -61"

Issue

• The server has frequent hangs, rcu_stalls, soft-lockups, hard lockups.
• The frequent log spamming done by nfsd, the following messages are seen.

516426.086069] ------------[ cut here ]------------
[516426.086077] WARNING: CPU: 4 PID: 17252 at fs/nfsd/nfsproc.c:805 nfserrno+0x58/0x70 [nfsd]
[516426.086078] nfsd: non-standard errno: -61  <<<=====
[516426.086119] CPU: 4 PID: 17252 Comm: nfsd Kdump: loaded Tainted: P        W  OEL ------------   3.10.0-1062.el7.x86_64 #1
[516426.086120] Hardware name: Dell Inc. PowerEdge R730/0WCJNT, BIOS 2.9.1 12/04/2018
[516426.086120] Call Trace:
[516426.086125]  [<ffffffff92179262>] dump_stack+0x19/0x1b
[516426.086128]  [<ffffffff91a9a878>] __warn+0xd8/0x100
[516426.086130]  [<ffffffff91a9a8ff>] warn_slowpath_fmt+0x5f/0x80
[516426.086133]  [<ffffffff91d26c83>] ? ima_file_check+0x63/0x1b0
[516426.086139]  [<ffffffffc09f5195>] ? sam_proc_get_lease+0x715/0xa30 [VSMqfs]
[516426.086147]  [<ffffffffc0a858f8>] nfserrno+0x58/0x70 [nfsd]
[516426.086151]  [<ffffffffc0a879cf>] nfsd_finish_read+0x9f/0xb0 [nfsd]
[516426.086156]  [<ffffffffc0a88dcc>] nfsd_readv+0x5c/0x70 [nfsd]
[516426.086162]  [<ffffffffc0a892c5>] nfsd_read+0x155/0x230 [nfsd]
[516426.086173]  [<ffffffffc0a92b9b>] nfsd3_proc_read+0xbb/0x170 [nfsd]
[516426.086183]  [<ffffffffc0a83810>] nfsd_dispatch+0xe0/0x290 [nfsd]
[516426.086216]  [<ffffffffc057f323>] svc_process_common+0x3d3/0x7c0 [sunrpc]
[516426.086238]  [<ffffffffc057f813>] svc_process+0x103/0x190 [sunrpc]
[516426.086248]  [<ffffffffc0a8316f>] nfsd+0xdf/0x150 [nfsd]
[516426.086259]  [<ffffffffc0a83090>] ? nfsd_destroy+0x80/0x80 [nfsd]
[516426.086263]  [<ffffffff91ac50d1>] kthread+0xd1/0xe0
[516426.086266]  [<ffffffff91ac5000>] ? insert_kthread_work+0x40/0x40
[516426.086269]  [<ffffffff9218bd37>] ret_from_fork_nospec_begin+0x21/0x21
[516426.086272]  [<ffffffff91ac5000>] ? insert_kthread_work+0x40/0x40
[516426.086274] ---[ end trace 3b5c866d50ddf958 ]---