CIFS mount inaccessible with an error "CIFS VFS: Error -104 sending data on socket to server"

Issue

• CIFS mount inaccessible with an error "CIFS VFS: Error -104 sending data on socket to server" followed by a blocked task message and a call trace that indicates the task is getting stuck waiting for the CIFS I/O completion:

Sep 16 00:21:43 sg1dbs1s kernel: CIFS VFS: Error -104 sending data on socket to server
Sep 16 00:21:43 sg1dbs1s kernel: CIFS VFS: Error -104 sending data on socket to server
Sep 16 00:21:43 sg1dbs1s kernel: CIFS VFS: Error -32 sending data on socket to server
Sep 16 00:26:27 sg1dbs1s kernel: INFO: task postgres:12987 blocked for more than 120 seconds.
Sep 16 00:26:27 sg1dbs1s kernel: "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Sep 16 00:26:27 sg1dbs1s kernel: postgres        D ffffffff816895f0     0 12987   8964 0x00000084
Sep 16 00:26:27 sg1dbs1s kernel: ffff8800ba293c50 0000000000000086 ffff8802b2bbce70 ffff8800ba293fd8
Sep 16 00:26:27 sg1dbs1s kernel: ffff8800ba293fd8 ffff8800ba293fd8 ffff8802b2bbce70 ffff8802bfc96c40
Sep 16 00:26:27 sg1dbs1s kernel: 0000000000000000 7fffffffffffffff ffff8802bffac3e8 ffffffff816895f0
Sep 16 00:26:27 sg1dbs1s kernel: Call Trace:
Sep 16 00:26:27 sg1dbs1s kernel: [<ffffffff816895f0>] ? bit_wait+0x50/0x50
Sep 16 00:26:27 sg1dbs1s kernel: [<ffffffff8168b579>] schedule+0x29/0x70
Sep 16 00:26:27 sg1dbs1s kernel: [<ffffffff81688fc9>] schedule_timeout+0x239/0x2d0
Sep 16 00:26:27 sg1dbs1s kernel: [<ffffffff810eaa6c>] ? ktime_get_ts64+0x4c/0xf0
Sep 16 00:26:27 sg1dbs1s kernel: [<ffffffff8113cb5f>] ? delayacct_end+0x8f/0xb0
Sep 16 00:26:27 sg1dbs1s kernel: [<ffffffff810eaa6c>] ? ktime_get_ts64+0x4c/0xf0
Sep 16 00:26:27 sg1dbs1s kernel: [<ffffffff816895f0>] ? bit_wait+0x50/0x50
Sep 16 00:26:27 sg1dbs1s kernel: [<ffffffff8168ab1e>] io_schedule_timeout+0xae/0x130
Sep 16 00:26:27 sg1dbs1s kernel: [<ffffffff8168abb8>] io_schedule+0x18/0x20
Sep 16 00:26:27 sg1dbs1s kernel: [<ffffffff81689601>] bit_wait_io+0x11/0x50
Sep 16 00:26:27 sg1dbs1s kernel: [<ffffffff81689125>] __wait_on_bit+0x65/0x90
Sep 16 00:26:27 sg1dbs1s kernel: [<ffffffff8117fb61>] wait_on_page_bit+0x81/0xa0
Sep 16 00:26:27 sg1dbs1s kernel: [<ffffffff810b16c0>] ? wake_bit_function+0x40/0x40
Sep 16 00:26:27 sg1dbs1s kernel: [<ffffffff8117fc91>] filemap_fdatawait_range+0x111/0x1b0
Sep 16 00:26:27 sg1dbs1s kernel: [<ffffffff8117fd57>] filemap_fdatawait+0x27/0x30
Sep 16 00:26:27 sg1dbs1s kernel: [<ffffffff81181ecc>] filemap_write_and_wait+0x4c/0x80
Sep 16 00:26:27 sg1dbs1s kernel: [<ffffffffa03e2db5>] cifs_flush+0x25/0x30 [cifs]
Sep 16 00:26:27 sg1dbs1s kernel: [<ffffffff811fb8d4>] filp_close+0x34/0x80
Sep 16 00:26:27 sg1dbs1s kernel: [<ffffffff8121cc38>] __close_fd+0x78/0xa0
Sep 16 00:26:27 sg1dbs1s kernel: [<ffffffff811fd473>] SyS_close+0x23/0x50
Sep 16 00:26:27 sg1dbs1s kernel: [<ffffffff816964c9>] system_call_fastpath+0x16/0x1b