kvm: x86: Adjust the location of pkru_mask of kvm_mmu to reduce memory

Adjust the field pkru_mask to the back of direct_map to make up 8-byte
alignment.This reduces the size of kvm_mmu by 8 bytes.
Signed-off-by: Peng Hao <flyingpeng@tencent.com>
Message-Id: <20220228030749.88353-1-flyingpeng@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/include/asm/kvm_host.h

@@ -443,14 +443,6 @@ struct kvm_mmu {
 	u8 shadow_root_level;
 	u8 ept_ad;
 	bool direct_map;
-	struct kvm_mmu_root_info prev_roots[KVM_MMU_NUM_PREV_ROOTS];
-
-	/*
-	 * Bitmap; bit set = permission fault
-	 * Byte index: page fault error code [4:1]
-	 * Bit index: pte permissions in ACC_* format
-	 */
-	u8 permissions[16];
 
 	/*
 	* The pkru_mask indicates if protection key checks are needed.  It
@@ -460,6 +452,15 @@ struct kvm_mmu {
 	*/
 	u32 pkru_mask;
 
+	struct kvm_mmu_root_info prev_roots[KVM_MMU_NUM_PREV_ROOTS];
+
+	/*
+	 * Bitmap; bit set = permission fault
+	 * Byte index: page fault error code [4:1]
+	 * Bit index: pte permissions in ACC_* format
+	 */
+	u8 permissions[16];
+
 	u64 *pae_root;
 	u64 *pml4_root;
 	u64 *pml5_root;