[PATCH v5 0/6] Cache coherency management subsystem

[Jonathan Cameron]

On Sat, 8 Nov 2025 20:02:52 +0000
Conor Dooley <conor at kernel.org> wrote:

> Arnd,
> 
> On Fri, Oct 31, 2025 at 11:17:03AM +0000, Jonathan Cameron wrote:
> > Support system level interfaces for cache maintenance as found on some
> > ARM64 systems. It is expected that systems using other CPU architectures
> > (such as RiscV) that support CXL memory and allow for native OS flows
> > will also use this. This is needed for correct functionality during
> > various forms of memory hotplug (e.g. CXL). Typical hardware has MMIO
> > interface found via ACPI DSDT. A system will often contain multiple
> > hardware instances.
> > 
> > Includes parameter changes to cpu_cache_invalidate_memregion() but no
> > functional changes for architectures that already support this call.
> > 
> > How to merge?
> > - Current suggestion would be via Conor's drivers/cache tree which routes
> >   through the SoC tree.  
> 
> I was gonna put this in linux-next, but I'm not really sure that Arnd
> was satisfied with the discussion on the previous version about
> suitability of the directory: https://lore.kernel.org/all/20251028114348.000006ed@huawei.com/
> 
> Arnd, did that response satisfy you, or nah?

Seems Arnd is busy.  Conor, if you are happy doing so, maybe push it to a tree
linux-next picks up, but hold off on the pull request until Arnd has had a chance
to reply?

Jonathan

> 
> Cheers,
> Conor.
> 
> >   *  Andrew Morton has expressed he is fine with the MM related changes
> >      going via another appropriate tree.
> >   *  CXL maintainers expressed that they don't consider it appropriate
> >      to go through theit tree.
> >   *  The tiny touching of Arm specific code has an ack from Catalin.  
>