Hi- I've been trying to track down some crashes when running NFS/RDMA tests over FastLinQ devices in iWARP mode. To make it stressful, I've enabled disconnect injection, where rpcrdma injects a connection disconnect every so often. As part of a disconnect event, the Receive and Send queues are drained. Sometimes I see a duplicate flush for one or more of memory registration ops. This is not a big deal for FastReq because its completion handler is basically a no-op. But for LocalInv this is a problem. On a flushed completion, the MR is destroyed. If the completion occurs again, of course, all kinds of badness happens because we're DMA-unmapping twice, touching memory that has already been freed, and deleting from a list_head that is poisonous. The last straw is that wc_localinv_done calls the generic RPC layer to indicate that an RPC Reply is ready. The duplicate flush dereferences one or more NULL pointers. Doesn't the verbs API contract stipulate that every posted WR gets exactly one completion? I don't see this behavior with other providers. Thanks for any advice. -- Chuck Lever
