+/*
+ * Non-present SPTE value for both VMX and SVM for TDP MMU.
In the previous patch, SHADOW_NONPRESENT_VALUE is also used in the
shadow MMU code. So here when you change SHADOW_NONPRESENT_VALUE to a
non-zero value, the "for TDP MMU" part doesn't stand.
I am wondering whether we can just avoid using SHADOW_NONPRESENT_VALUE
in shadow MMU code in the previous patch, and state explicitly that we
are only going to support TDP MMU for non-zero value for non-present SPTE?
+ * For SVM NPT, for non-present spte (bit 0 = 0), other bits are ignored.
+ * For VMX EPT, bit 63 is ignored if #VE is disabled. (EPT_VIOLATION_VE=0)
+ * bit 63 is #VE suppress if #VE is enabled. (EPT_VIOLATION_VE=1)
+ * For TDX:
+ * TDX module sets EPT_VIOLATION_VE for Secure-EPT and conventional EPT
+ */
+#ifdef CONFIG_X86_64
+#define SHADOW_NONPRESENT_VALUE BIT_ULL(63)
+static_assert(!(SHADOW_NONPRESENT_VALUE & SPTE_MMU_PRESENT_MASK));
+#else
#define SHADOW_NONPRESENT_VALUE 0ULL
+#endif
extern u64 __read_mostly shadow_host_writable_mask;
extern u64 __read_mostly shadow_mmu_writable_mask;
@@ -196,7 +209,7 @@ extern u64 __read_mostly shadow_nonpresent_or_rsvd_mask;
*
* Only used by the TDP MMU.
*/
-#define REMOVED_SPTE 0x5a0ULL
+#define REMOVED_SPTE (SHADOW_NONPRESENT_VALUE | 0x5a0ULL)
I kinda prefer moving this chunk to the previous patch, because the
reason to have SHADOW_NONPRESENT_VALUE is to have a non-zero value for
non-present SPTEs, which include the REMOVED_SPTE.
But just my 2cents.
