[openib-general] Re: FW: SDP problems with 64K page size

[Michael S. Tsirkin]

Quoting r. Roland Dreier <rolandd at cisco.com>:
> Subject: FW: SDP problems with 64K page size
> 
> Hi, Jerome asked me to forward this on, since for some reason his
> email didn't appear when he sent it.
> 
> In any case there seem to be some PAGE_SIZE dependencies in SDP.
> Libor provided a patch that fixed this up a while ago, but I don't
> know if this is the right way to handle this.
> 
>  - R.

Roland, thanks very much for forwarding this, and for providing
a patch to Jerome.

The problem is with recv_size/send_size counters in SDP, which are u16,
so that assigning a value of 64K overflows them.
The best way to fix this appears to be to bump the counters up to u32 or s32.
The patch that Roland posted fixes this by reducing the buffer
size to 16K, so that should work, too.

Roland, I might check in the patch that you posted to work around
this problem for 64K page users, until I have a final fix ready.
Is that OK with everyone?

Thanks,

-- 
MST