Re: [PATCH v9 00/22] Enable FRED with KVM VMX
From: Sean Christopherson
Date: Thu Nov 13 2025 - 17:20:20 EST
On Thu, Nov 06, 2025, Xin Li wrote:
>
> > On Oct 26, 2025, at 1:18 PM, Xin Li (Intel) <xin@xxxxxxxxx> wrote:
> > Although FRED and CET supervisor shadow stacks are independent CPU
> > features, FRED unconditionally includes FRED shadow stack pointer
> > MSRs IA32_FRED_SSP[0123], and IA32_FRED_SSP0 is just an alias of the
> > CET MSR IA32_PL0_SSP. IOW, the state management of MSR IA32_PL0_SSP
> > becomes an overlap area, and Sean requested that FRED virtualization
> > to land after CET virtualization [1].
> >
> > With CET virtualization now merged in v6.18, the path is clear to submit
> > the FRED virtualization patch series :).
>
> Sean, what is the plan for the FRED patch series?
Review and merge it asap. Unfortunately, "asap" isn't all that soon, mostly
because I've been bogged down with non-upstream stuff. I'm hoping to dive in
next week (but take that with a grain of salt; I've more or less said that exact
thing to someone else for other patches for three weeks running).