Re: [PATCH] cxl/mbox: Check enabled_cmds before sending SET_SHUTDOWN_STATE

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

alison.schofield@ wrote:
> From: Alison Schofield <alison.schofield@intel.com>
> 
> The CXL specification defines CXL_MBOX_OP_SET_SHUTDOWN_STATE as
> optional. Check the enabled_cmds bitmap before sending to device.

Table 8-126 defines it as mandatory for devices that support PMEM, see
the "PM" in the "Mailbox" column.

> This appeared with cxl-test where mock support for this command
> is not present and -EIO is returned, leading to a WARN_ONCE()
> stack trace and dev_warn()'s on every cxl_nvdimm_probe.

Davidlohr and I talked about this here:

http://lore.kernel.org/679430b145dc0_20fa2947b@dwillia2-xfh.jf.intel.com.notmuch

The plan was to follow up with mock device support... oh, that came in
on Tuesday, I need to go take a look at that:

http://lore.kernel.org/20250205040842.1253616-1-dave@stgolabs.net

> Signed-off-by: Alison Schofield <alison.schofield@intel.com>
> ---
> 
> Not sure what we actually want to do when not supported.
> Most cmds just return 0, like I did here, but maybe for
> this functionality something more is warranted.
> 
> wrt cxl-test support, also not sure if this feature wants some
> round-trip testing support via cxl-test mocking. I do like the
> -EIO from cxl-test as a loud reminder when running cxl-test 
> that something new has come in that cxl-test doesn't know about.

Have a look at that follow-up series and see if it addresses the
concerns.