[PATCH 00/10] KVM: x86: Fix LVTPC masking on AMD CPUs

From: Sean Christopherson
Date: Fri Apr 05 2024 - 19:56:17 EST


This is kinda sorta v2 of Sandipan's fix for KVM's incorrect setting of
the MASK bit when delivering PMIs through the LVTPC.

It's a bit rushed, as I want to get Sandipan's fix applied early next
week so that it can make its way to Linus' tree for -rc4. And I didn't
want to apply Sandipan's patch as-is, because I'm a little paranoid that
the guest CPUID check could be noticeable slow, and it's easy to avoid.

My plan is to grab patches 1-2 for 6.9 asap, and let the rest simmer for
much, much longer (they are *very* lightly tested).

As for why this looks wildy different than Sandipan's compat_vendor idea,
when I started looking at KVM's various AMD vs. Intel checks, I realized
it makes no sense to support an "unknown" vendor. KVM can't do *nothing*,
and so practically speaking, an "unknown" vendor vCPU would actually end
up with a weird mix of AMD *and* Intel behavior, not AMD *or* Intel
behavior.

Sandipan Das (1):
KVM: x86/pmu: Do not mask LVTPC when handling a PMI on AMD platforms

Sean Christopherson (9):
KVM: x86: Snapshot if a vCPU's vendor model is AMD vs. Intel
compatible
KVM: x86/pmu: Squash period for checkpointed events based on host
HLE/RTM
KVM: x86: Apply Intel's TSC_AUX reserved-bit behavior to Intel compat
vCPUs
KVM: x86: Inhibit code #DBs in MOV-SS shadow for all Intel compat
vCPUs
KVM: x86: Use "is Intel compatible" helper to emulate SYSCALL in
!64-bit
KVM: SVM: Emulate SYSENTER RIP/RSP behavior for all Intel compat vCPUs
KVM: x86: Allow SYSENTER in Compatibility Mode for all Intel compat
vCPUs
KVM: x86: Open code vendor_intel() in string_registers_quirk()
KVM: x86: Bury guest_cpuid_is_amd_or_hygon() in cpuid.c

arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kvm/cpuid.c | 13 ++++++
arch/x86/kvm/cpuid.h | 16 ++------
arch/x86/kvm/emulate.c | 71 ++++++++++-----------------------
arch/x86/kvm/kvm_emulate.h | 1 +
arch/x86/kvm/lapic.c | 3 +-
arch/x86/kvm/mmu/mmu.c | 2 +-
arch/x86/kvm/pmu.c | 2 +-
arch/x86/kvm/svm/svm.c | 14 +++----
arch/x86/kvm/x86.c | 30 ++++++++------
10 files changed, 68 insertions(+), 85 deletions(-)


base-commit: 8cb4a9a82b21623dbb4b3051dd30d98356cf95bc
--
2.44.0.478.gd926399ef9-goog