I am also facing lmrc driver issue.  I recently purchased DELL R750xs with PERC H755(in passthrough mode) consisting of 5disk.

I am running latest DELL BIOS. Can someone help me on this.

Aug 26 05:17:43 server1 lmrc: [ID 408335 kern.warning] WARNING: lmrc0: resetting...
Aug 26 05:17:43 server1 lmrc: [ID 408335 kern.warning] WARNING: lmrc0: resetting...
Aug 26 05:17:44 server1 lmrc: [ID 408335 kern.warning] WARNING: lmrc0: resetting...
Aug 26 05:17:44 server1 lmrc: [ID 383856 kern.warning] WARNING: lmrc0: reset failed
Aug 26 05:17:44 server1 lmrc: [ID 998901 kern.warning] WARNING: lmrc0: AEN failed, status = 255
Aug 26 05:17:44 server1 lmrc: [ID 380853 kern.warning] WARNING: lmrc0: LD target map sync failed, status = 255
Aug 26 05:17:44 server1 lmrc: [ID 831201 kern.warning] WARNING: lmrc0: PD map sync failed, status = 255
Aug 26 05:17:44 server1 lmrc: [ID 383856 kern.warning] WARNING: lmrc0: reset failed
Aug 26 05:17:44 server1 zfs: [ID 961531 kern.warning] WARNING: Pool 'dpool' has encountered an uncorrectable I/O failure and has been suspended; `zpool
clear` will be required before the pool can be written to.
Aug 26 05:17:59 server1 scsi: [ID 107833 kern.warning] WARNING: /pci@bc,0/pci8086,347c@4/pci1028,1ae1@0/iport@v0/disk@5000c500f8162e4f,0 (sd2):#012#011d
rive offline#012
Aug 26 05:18:00 server1 scsi: [ID 107833 kern.warning] WARNING: /pci@bc,0/pci8086,347c@4/pci1028,1ae1@0/iport@v0/disk@5000c500f815d253,0 (sd6):#012#011d
rive offline#012
Aug 26 05:18:00 server1 scsi: [ID 107833 kern.warning] WARNING: /pci@bc,0/pci8086,347c@4/pci1028,1ae1@0/iport@v0/disk@5000c500f815ba63,0 (sd5):#012#011d
rive offline#012
Aug 26 05:18:00 server1 scsi: [ID 107833 kern.warning] WARNING: /pci@bc,0/pci8086,347c@4/pci1028,1ae1@0/iport@v0/disk@5000c500f815e003,0 (sd3):#012#011d
rive offline#012