KVM: nVMX: Add a TSC multiplier field in VMCS12

This is required for supporting nested TSC scaling.
Signed-off-by: Ilias Stamatis <ilstam@amazon.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20210526184418.28881-6-ilstam@amazon.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/vmx/vmcs12.c

@@ -37,6 +37,7 @@ const unsigned short vmcs_field_to_offset_table[] = {
 	FIELD64(VM_ENTRY_MSR_LOAD_ADDR, vm_entry_msr_load_addr),
 	FIELD64(PML_ADDRESS, pml_address),
 	FIELD64(TSC_OFFSET, tsc_offset),
+	FIELD64(TSC_MULTIPLIER, tsc_multiplier),
 	FIELD64(VIRTUAL_APIC_PAGE_ADDR, virtual_apic_page_addr),
 	FIELD64(APIC_ACCESS_ADDR, apic_access_addr),
 	FIELD64(POSTED_INTR_DESC_ADDR, posted_intr_desc_addr),

arch/x86/kvm/vmx/vmcs12.h

@@ -70,7 +70,8 @@ struct __packed vmcs12 {
 	u64 eptp_list_address;
 	u64 pml_address;
 	u64 encls_exiting_bitmap;
-	u64 padding64[2]; /* room for future expansion */
+	u64 tsc_multiplier;
+	u64 padding64[1]; /* room for future expansion */
 	/*
 	 * To allow migration of L1 (complete with its L2 guests) between
 	 * machines of different natural widths (32 or 64 bit), we cannot have
@@ -258,6 +259,7 @@ static inline void vmx_check_vmcs12_offsets(void)
 	CHECK_OFFSET(eptp_list_address, 304);
 	CHECK_OFFSET(pml_address, 312);
 	CHECK_OFFSET(encls_exiting_bitmap, 320);
+	CHECK_OFFSET(tsc_multiplier, 328);
 	CHECK_OFFSET(cr0_guest_host_mask, 344);
 	CHECK_OFFSET(cr4_guest_host_mask, 352);
 	CHECK_OFFSET(cr0_read_shadow, 360);