[ofiwg] Verbs dma-buf detection question

[Jason Gunthorpe]

On Mon, Mar 29, 2021 at 04:52:43PM +0300, Gal Pressman via ofiwg wrote:
> Hey,
> 
> I'm looking at the code that tests the kernel for umem dma-buf support in
> vrb_set_dmabuf_support() and wondering if I'm missing anything.
> 
> The code checks /proc/kallsyms for the ib_umem_dmabuf_get() symbol existence,
> which kinda treats it as ABI, although the kernel symbol name could change at
> any time.
> 
> Wondering what other people thoughts are? Maybe a better detection method is
> called for?

Expunge such an ridiculous thing from libfabric with fire.

Call ib_umem_dmabuf_get() and check for EOPNOTSUPP

Jason