linux-kernel - Re: [PATCH v4 09/25] KVM: VMX: nVMX: Support TSC scaling and PERF_GLOBAL

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <YuMPHCanuPtYEN4j@google.com>
Date:   Thu, 28 Jul 2022 22:35:08 +0000
From:   Sean Christopherson <seanjc@...gle.com>
To:     Paolo Bonzini <pbonzini@...hat.com>
Cc:     Vitaly Kuznetsov <vkuznets@...hat.com>, kvm@...r.kernel.org,
        Anirudh Rayabharam <anrayabh@...ux.microsoft.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Jim Mattson <jmattson@...gle.com>,
        Maxim Levitsky <mlevitsk@...hat.com>,
        linux-hyperv@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v4 09/25] KVM: VMX: nVMX: Support TSC scaling and
 PERF_GLOBAL_CTRL with enlightened VMCS

On Fri, Jul 29, 2022, Paolo Bonzini wrote:
> On 7/29/22 00:13, Sean Christopherson wrote:
> > The only flaw in this is if KVM gets handed a CPUID model that enumerates support
> > for 2025 (or whenever the next update comes) but not 2022.  Hmm, though if Microsoft
> > defines each new "version" as a full superset, then even that theoretical bug goes
> > away.  I'm happy to be optimistic for once and give this a shot.  I definitely like
> > that it makes it easier to see the deltas between versions.
> 
> Okay, I have queued the series but I still haven't gone through all the
> comments.  So this will _not_ be in the 5.21 pull request.

I assume you meant 5.20?

> The first patch also needs a bit more thought to figure out the impact on
> userspace and whether we can consider syndbg niche enough to not care.
> 
> Paolo
>