Re: [RFC PATCH v2 0/5] KVM: SVM: Enable AVIC by default on Zen 4+

[Sean Christopherson <seanjc@google.com>]

On Thu, Sep 04, 2025, Naveen N Rao (AMD) wrote:
> This is v2 of the RFC posted here:
> http://lkml.kernel.org/r/20250626145122.2228258-1-naveen@kernel.org
> 
> I have split up the patches and incorporated feedback on the RFC. This 
> still depends on at least two other fixes:
> - Reducing SVM IRQ Window inhibit lock contention: 
>   http://lkml.kernel.org/r/cover.1752819570.git.naveen@kernel.org

Eh, I don't think this one in is a hard dependency.  Don't get me wrong, I want
to land that series, ideally at the same time that AVIC is (conditionally) enabled
by default, but I won't lose sleep if it lands a kernel or two later (tagged for
stable@ as appropriate).

Practically speaking, no feature the size of AVIC will ever be perfect.  At this
point, I'm comfortable enabling AVIC by default and fixing-forward any remaining
issues.  And I want to get AVIC enabled by default in 6.18 because I think that
enabling AVIC in an LTS will be a big net positive for the overall KVM community.
E.g. we'll likely get more exposure/coverage when distros/companies move to the
next LTS, it'll be easier to manage LTS backports for downstream frankenkernels,
etc.

> - Fixing TPR handling when AVIC is active: 
>   http://lkml.kernel.org/r/cover.1756139678.git.maciej.szmigiero@oracle.com

This is queued for 6.17, just need to send the "thank you" and the PULL request.

As for this series, I'll post a v3 as time is running short for 6.18 (one of those
situations where describing the changes I'm suggesting would take longer than just
making the changes :-/).