Re: [BUG] cxl can not create region

[Dan Williams <dan.j.williams@intel.com>]

Dan Williams wrote:
> Bobo WL wrote:
> > Hi Dan,
> > 
> > Thanks for your reply!
> > 
> > On Mon, Aug 8, 2022 at 11:58 PM Dan Williams <dan.j.williams@intel.com> wrote:
> > >
> > > What is the output of:
> > >
> > >     cxl list -MDTu -d decoder0.0
> > >
> > > ...? It might be the case that mem1 cannot be mapped by decoder0.0, or
> > > at least not in the specified order, or that validation check is broken.
> > 
> > Command "cxl list -MDTu -d decoder0.0" output:
> 
> Thanks for this, I think I know the problem, but will try some
> experiments with cxl_test first.

Hmm, so my cxl_test experiment unfortunately passed so I'm not
reproducing the failure mode. This is the result of creating x4 region
with devices directly attached to a single host-bridge:

# cxl create-region -d decoder3.5 -w 4 -m -g 256 mem{12,10,9,11} -s $((1<<30))
{
  "region":"region8",
  "resource":"0xf1f0000000",
  "size":"1024.00 MiB (1073.74 MB)",
  "interleave_ways":4,
  "interleave_granularity":256,
  "decode_state":"commit",
  "mappings":[
    {
      "position":3,
      "memdev":"mem11",
      "decoder":"decoder21.0"
    },
    {
      "position":2,
      "memdev":"mem9",
      "decoder":"decoder19.0"
    },
    {
      "position":1,
      "memdev":"mem10",
      "decoder":"decoder20.0"
    },
    {
      "position":0,
      "memdev":"mem12",
      "decoder":"decoder22.0"
    }
  ]
}
cxl region: cmd_create_region: created 1 region

> Did the commit_store() crash stop reproducing with latest cxl/preview
> branch?

I missed the answer to this question.

All of these changes are now in Linus' tree perhaps give that a try and
post the debug log again?