[LU-2896] IR enabled MGS don't able to register old OST

• Type: Bug
• Resolution: Fixed
• Priority: Blocker
• Fix Version/s: Lustre 2.4.0
• Affects Version/s: Lustre 2.3.0, Lustre 2.4.0
• Labels: LB patch
• Environment: OST 2.1, MGS 2.1+ported IR patch.
• Severity: 3
• Assignee: James Nunez (Inactive)
• Reporter: Alexey Lyashkov

Description

Xyratex port IR patch from upstream to own code and see MGS don't able to register old OST in new MGS, with EINVAL.

collecting logs point to
mgs_handle_target_reg function and code

        /* Do not support unregistering right now. */
        if (opc != LDD_F_OPC_REG)
                GOTO(out_nolock, rc = -EINVAL);

in case 2.1 OST (or any pre IR target) don't set any flag from list

#define LDD_F_OPC_REG   0x10000000
#define LDD_F_OPC_UNREG 0x20000000
#define LDD_F_OPC_READY 0x40000000
#define LDD_F_OPC_MASK  0xf0000000

at own side and opc is zero. that broke target to be register.

PS. did you have interoperability testing for IR ?