Re: [GIT pull] irq/core for v6.2-rc1

[Thomas Gleixner]

On Mon, Dec 12 2022 at 09:07, John Stoffel wrote:
>> 
>>    IMS (Interrupt Message Store] is a new specification which allows device
>>    manufactures to provide implementation defined storage for MSI messages
>>    contrary to the uniform and specification defined storage mechanisms for
>
> This sentence reads strangley to me, I'm not quite clear on what
> "uniform and specification" really means here.  Just a minor nit since
> I spent three or four re-reads trying to understand this otherwise
> really nicely written history!

Yeah, it reads a bit strange. What I wanted to say is:

   IMS has an implementation defined message store while PCI/MSI[-X] has
   a specified message store which is uniform accross all devices. That
   uniformity allowed us to get away with "global" PCI/MSI domains.

>>    The initial PCI/MSI[-X] support obviously plugged into this model which
>>    resulted in some basic shared infrastructure in the PCI core code for
>>    setting up MSI descriptors, which are a pure software construct for holding
>>    data relevant for a particular MSI interrupt, but the actual association to
>>    Linux interrupts was completely architecture specific. This model is still
>>    supported today to keep museum architectures and notorious stranglers
>
> I think you mean "stragglers" not "stranglers.  Though I'm sure you
> wanted to strangle things at points!

Indeed.

Thanks,

        tglx