Re: [PATCH v6 3/9] cxl/region: Skip decoder reset on detach for autodiscovered regions

Koralahalli Channabasappa, Smita
2026-03-12T21:28:48Z

On 3/12/2026 12:53 PM, Dan Williams wrote:
> Dan Williams wrote:
> [..]
>> All of this wants some documentation to tell users that the rule is
>> "Hey, after any endpoint decoder has been seen by the CXL core, if you
>> remove that endpoint decoder by removing or disabling any of cxl_acpi,
>> cxl_mem, or cxl_port the CXL core *will* violently destroy the decode
>> configuration". Then think about whether this needs a way to specify
>> "skip decoder teardown" to disambiguate "the decoder is disappearing
>> logically, but not physically, keep its configuration". That allows
>> turning any manual configuration into an auto-configuration and has an
>> explicit rule for all regions rather than the current "auto regions are
>> special" policy.
>
> Do not worry about this paragraph of feedback. I will start a new patch
> set to address this issue. It is the same problem impacting the
> accelerator series where driver reload resets the decode configuration
> by default. Both accelerator drivers and userspace should be able to
> opt-out / opt-in to that behavior.
>
> This will want some indication that the root decoder space is designated
> such that it does not get reassigned while the driver is detached.

Sure, this patch is not needed for SR series as region teardown is been
dropped. I will exclude this while sending v7

Thanks
Smita