RHEL6: A server installed with IBM's tape library manager lin_tape is crashing frequently.

Issue

• System crashing in the lin_tape module with the following panic signature:

[...]
RIP: 0010:[<ffffffff8124ec20>]  [<ffffffff8124ec20>] elv_may_queue+0x10/0x20
RSP: 0018:ffff8808233e95c0  EFLAGS: 00010097
RAX: 0000000000000000 RBX: ffff88082a3eeca0 RCX: 0000000000000010
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88082a3eeca0
RBP: ffff8808233e95c0 R08: 00000000000000ff R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffff8808224bda80 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8800282c0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
CR2: 0000000000000078 CR3: 000000080d2db000 CR4: 00000000000406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[...]
Call Trace:
 [<ffffffff81258649>] get_request+0x49/0x3c0
 [<ffffffff812589ea>] get_request_wait+0x2a/0x1d0
 [<ffffffff812731c0>] ? idr_get_empty_slot+0x110/0x2c0
 [<ffffffff81259176>] blk_get_request+0x46/0xa0
 [<ffffffffa037abd0>] lin_tape_blk_rq+0x40/0x5e0 [lin_tape]
[...]