Merge tag 'kvm-x86-misc-6.12' of https://github.com/kvm-x86/linux into HEAD

KVM x86 misc changes for 6.12

 - Advertise AVX10.1 to userspace (effectively prep work for the "real" AVX10
   functionality that is on the horizon).

 - Rework common MSR handling code to suppress errors on userspace accesses to
   unsupported-but-advertised MSRs.  This will allow removing (almost?) all of
   KVM's exemptions for userspace access to MSRs that shouldn't exist based on
   the vCPU model (the actual cleanup is non-trivial future work).

 - Rework KVM's handling of x2APIC ICR, again, because AMD (x2AVIC) splits the
   64-bit value into the legacy ICR and ICR2 storage, whereas Intel (APICv)
   stores the entire 64-bit value a the ICR offset.

 - Fix a bug where KVM would fail to exit to userspace if one was triggered by
   a fastpath exit handler.

 - Add fastpath handling of HLT VM-Exit to expedite re-entering the guest when
   there's already a pending wake event at the time of the exit.

 - Finally fix the RSM vs. nested VM-Enter WARN by forcing the vCPU out of
   guest mode prior to signalling SHUTDOWN (architecturally, the SHUTDOWN is
   supposed to hit L1, not L2).

1 files changed, 6 insertions, 4 deletions

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 89682832dded..0663b1fea2b9 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -1998,15 +1998,15 @@ static inline bool is_vmx_feature_control_msr_valid(struct vcpu_vmx *vmx,
 	return !(msr->data & ~valid_bits);
 }
 
-int vmx_get_msr_feature(struct kvm_msr_entry *msr)
+int vmx_get_feature_msr(u32 msr, u64 *data)
 {
-	switch (msr->index) {
+	switch (msr) {
 	case KVM_FIRST_EMULATED_VMX_MSR ... KVM_LAST_EMULATED_VMX_MSR:
 		if (!nested)
 			return 1;
-		return vmx_get_vmx_msr(&vmcs_config.nested, msr->index, &msr->data);
+		return vmx_get_vmx_msr(&vmcs_config.nested, msr, data);
 	default:
-		return KVM_MSR_RET_INVALID;
+		return KVM_MSR_RET_UNSUPPORTED;
 	}
 }
 
@@ -7265,6 +7265,8 @@ static fastpath_t vmx_exit_handlers_fastpath(struct kvm_vcpu *vcpu,
 		return handle_fastpath_set_msr_irqoff(vcpu);
 	case EXIT_REASON_PREEMPTION_TIMER:
 		return handle_fastpath_preemption_timer(vcpu, force_immediate_exit);
+	case EXIT_REASON_HLT:
+		return handle_fastpath_hlt(vcpu);
 	default:
 		return EXIT_FASTPATH_NONE;
 	}