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| author |   Sean Christopherson <seanjc@google.com> | 2024-11-27 17:34:17 -0800 |
|---|---|---|
| committer | Sean Christopherson <seanjc@google.com> | 2024-12-18 14:20:15 -0800 |
| commit | 8f2a27752e808f16f3baf1939a91c42966f22a08 (patch) | |
| tree | 49b9d2fa61755ec819b70754081e43128f8e9231 /arch/x86/kvm/lapic.c | |
| parent | KVM: x86: Shuffle code to prepare for dropping guest_cpuid_has() (diff) | |
| download | wireguard-linux-8f2a27752e808f16f3baf1939a91c42966f22a08.tar.xz wireguard-linux-8f2a27752e808f16f3baf1939a91c42966f22a08.zip | |
KVM: x86: Replace (almost) all guest CPUID feature queries with cpu_caps
Switch all queries (except XSAVES) of guest features from guest CPUID to
guest capabilities, i.e. replace all calls to guest_cpuid_has() with calls
to guest_cpu_cap_has().
Keep guest_cpuid_has() around for XSAVES, but subsume its helper
guest_cpuid_get_register() and add a compile-time assertion to prevent
using guest_cpuid_has() for any other feature. Add yet another comment
for XSAVE to explain why KVM is allowed to query its raw guest CPUID.
Opportunistically drop the unused guest_cpuid_clear(), as there should be
no circumstance in which KVM needs to _clear_ a guest CPUID feature now
that everything is tracked via cpu_caps. E.g. KVM may need to _change_
a feature to emulate dynamic CPUID flags, but KVM should never need to
clear a feature in guest CPUID to prevent it from being used by the guest.
Delete the last remnants of the governed features framework, as the lone
holdout was vmx_adjust_secondary_exec_control()'s divergent behavior for
governed vs. ungoverned features.
Note, replacing guest_cpuid_has() checks with guest_cpu_cap_has() when
computing reserved CR4 bits is a nop when viewed as a whole, as KVM's
capabilities are already incorporated into the calculation, i.e. if a
feature is present in guest CPUID but unsupported by KVM, its CR4 bit
was already being marked as reserved, checking guest_cpu_cap_has() simply
double-stamps that it's a reserved bit.
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Link: https://lore.kernel.org/r/20241128013424.4096668-51-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Diffstat (limited to '')
| -rw-r--r-- | arch/x86/kvm/lapic.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 3c83951c619e..ae81ae27d534 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -598,7 +598,7 @@ void kvm_apic_set_version(struct kvm_vcpu *vcpu) * version first and level-triggered interrupts never get EOIed in * IOAPIC. */ - if (guest_cpuid_has(vcpu, X86_FEATURE_X2APIC) && + if (guest_cpu_cap_has(vcpu, X86_FEATURE_X2APIC) && !ioapic_in_kernel(vcpu->kvm)) v |= APIC_LVR_DIRECTED_EOI; kvm_lapic_set_reg(apic, APIC_LVR, v); @@ -2634,7 +2634,7 @@ int kvm_apic_set_base(struct kvm_vcpu *vcpu, u64 value, bool host_initiated) return 0; u64 reserved_bits = kvm_vcpu_reserved_gpa_bits_raw(vcpu) | 0x2ff | - (guest_cpuid_has(vcpu, X86_FEATURE_X2APIC) ? 0 : X2APIC_ENABLE); + (guest_cpu_cap_has(vcpu, X86_FEATURE_X2APIC) ? 0 : X2APIC_ENABLE); if ((value & reserved_bits) != 0 || new_mode == LAPIC_MODE_INVALID) return 1; |