From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.1.9) Gecko/20071105 Fedora/2.0.0.9-1.fc7 Firefox/2.0.0.9 Description of problem: I have following code to issue SCSI_IOCTL_GET_IDLUN unsigned int flags = O_RDWR | O_NONBLOCK; unsigned int status, id[2], deviceId; deviceId = open(deviceName.c_str(), flags); status = ioctl (deviceId, SCSI_IOCTL_GET_IDLUN, &id); This call fails if deviceName is of type /dev/mapper/mpath4 This call is successfull for normal scsi devices. /dev/sdh # multipath -l mpath4 mpath4 (360060480000290300149533030303743) [size=4 GB][features="0"][hwhandler="0"] \_ round-robin 0 [active] \_ 1:0:0:92 sdh 8:112 [active][ready] \_ 1:0:1:92 sdo 8:224 [active][ready] \_ 2:0:0:92 sdx 65:112 [active][ready] Same is the case of call SCSI_IOCTL_SEND_COMMAND - I use this to read SCSI mod pages for device inquiry SG_IO - I use this to issue SCSI3 Persistent Group Reservation Version-Release number of selected component (if applicable): device-mapper-1.02.07-4.0.RHEL4, device-mapper-1.02.07-4.0.RHEL4, device-mapper-multipath-0.4.5-16.1.RHEL4 device-mapper-multipath-0.4.5-16.1.RHEL4 How reproducible: Always Steps to Reproduce: 1. Write code which accepts device path and issue above mentioned IOCTLS 2. Run the code mentioned above by passing device path generated by device-mapper multipath module. Actual Results: SCSI_IOCTL_SEND_COMMAND, SG_IO and SCSI_IOCTL_GET_IDLUN device calls fails on /dev/mapper/mpath4 Expected Results: SCSI_IOCTL_SEND_COMMAND, SG_IO and SCSI_IOCTL_GET_IDLUN calls should pass on /dev/mapper/mpath4 and return appropriate data. Additional info:
I think we added this support for this to the kernel in 4.5.0: please try that, and if you still have problems, reopen this.