[ofa-general] Re: [PATCH] IB/core - reset to error state transition not allowed

[Ralph Campbell]

On Wed, 2008-04-23 at 10:55 -0700, Roland Dreier wrote:
>  > I was reviewing the QP state transition diagram in the IB 1.2.1
>  > spec. and the code for qp_state_table[], and noticed that
>  > the code allows a QP to be modified from IB_QPS_RESET to
>  > IB_QPS_ERR whereas the notes for figure 124 (pg 457)
>  > specifically says that this transition isn't allowed.
> 
> This is a change from the 1.2 spec, which says:
> 
>   It is possible to transition from any state to either the Error state
>   or the Reset state with the Modify QP/EE Verb.
> 
> Does anyone know why this change was made?  We specifically added code
> to some low-level drivers to handle RESET->ERROR transitions, so I guess
> someone cared (although maybe it was just for absolute spec compliance).
> 
>  - R.

I didn't realize what a can of worms I opened :-)
Personally, I don't think this will affect most applications
either way. I posted the patch thinking it was an obvious bug.
The only case that I think matters is some program which
tries to verify the spec. (pick one).