RE: [PATCH v3 0/2] Add log related mailbox commands

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

sthanneeru.opensrc@ wrote:
> From: Srinivasulu Thanneeru <sthanneeru.opensrc@micron.com>
> 
> Add support to expose following mailbox commands to userspace
> for clearing and populating the Vendor debug log in certain
> scenarios, allowing for the aggregation of results over time.
> 
> 1. CXL r3.1 8.2.9.5.3 Get Log Capabilities.
> 2. CXL r3.1 8.2.9.5.4 Clear Log commands.
> 3. CXL r3.1 8.2.9.5.6 Get Supported Logs Sub-List.
> 
> ---
> Changes in v3:
> - 'Component State Dump log' has several caveats for ioctl()
>    not being a suitable ABI as pointed in v2.(Dan Williams)
> - Remove Component State Dump from Clear log filter.
> - Implement a seperate patch(yet to do) to address issues as pointed in v2.

Circling back to this question... I had overlooked the fact that in v3.1
the "Request Abort Background Operation" command was added (8.2.9.1.5).
With that the kernel can safely support background commands with
indefinite residency. So as long as the device supports that command and
advertises that Log populate requests can be cancelled then we can build
a facility to cancel any user-submitted background commands when a
kernel internal need for the background command slot arises.