[Question] Issue with ND_MR Deregistration (0x80000011) when using Memory Windows in NetworkDirect

[ymf1]

Hi Jijos,

Hope this email finds you well.
I am currently developing an RDMA application using NetworkDirect and have encountered a tricky issue regarding Memory Windows (MW) and Memory Regions (MR). I would greatly appreciate your expert advice on this.
The Issue:
I am unable to deregister an MR after it has been bound to a Memory Window.
My Workflow:
I register an MR.
I bind this MR to a Memory Window (MW).
During the cleanup/release phase, I first call Invalidate on the MW.
Immediately after, I attempt to deregister the MR.
The Error:
The MR deregistration fails with error 0x80000011 (ND_INVALID_PARAMETER / The format of the type name is invalid).
Observations:
If I do not use MW and simply register/deregister the MR locally, everything works fine.
The issue only occurs when the MR has been bound to an MW.
It seems that once the MR is bound to the MW, the deregistration is blocked, causing a memory leak in my application.
Could you please provide some insights or suggestions on the correct sequence for invalidating MWs and deregistering the associated MRs?
Thank you very much for your time and help.
Best regards,
Mengfei Yi

[MrDavid949]

The memory region cannot be deregistered when a memory window is bound to it. The correct order for cleanup is to either unbind or release the MW, then you can deregister the MR.