File 62a1e5d2-x86-introduce-_PAGE_-for-mem-types.patch of Package xen.28171
# Commit 1be8707c75bf4ba68447c74e1618b521dd432499
# Date 2022-06-09 14:21:38 +0200
# Author Andrew Cooper <andrew.cooper3@citrix.com>
# Committer Jan Beulich <jbeulich@suse.com>
x86/page: Introduce _PAGE_* constants for memory types
... rather than opencoding the PAT/PCD/PWT attributes in __PAGE_HYPERVISOR_*
constants. These are going to be needed by forthcoming logic.
No functional change.
This is part of XSA-402.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
--- a/xen/include/asm-x86/page.h
+++ b/xen/include/asm-x86/page.h
@@ -344,6 +344,14 @@ void efi_update_l4_pgtable(unsigned int
#define PAGE_CACHE_ATTRS (_PAGE_PAT | _PAGE_PCD | _PAGE_PWT)
+/* Memory types, encoded under Xen's choice of MSR_PAT. */
+#define _PAGE_WB ( 0)
+#define _PAGE_WT ( _PAGE_PWT)
+#define _PAGE_UCM ( _PAGE_PCD )
+#define _PAGE_UC ( _PAGE_PCD | _PAGE_PWT)
+#define _PAGE_WC (_PAGE_PAT )
+#define _PAGE_WP (_PAGE_PAT | _PAGE_PWT)
+
/*
* Debug option: Ensure that granted mappings are not implicitly unmapped.
* WARNING: This will need to be disabled to run OSes that use the spare PTE
@@ -362,8 +370,8 @@ void efi_update_l4_pgtable(unsigned int
#define __PAGE_HYPERVISOR_RX (_PAGE_PRESENT | _PAGE_ACCESSED)
#define __PAGE_HYPERVISOR (__PAGE_HYPERVISOR_RX | \
_PAGE_DIRTY | _PAGE_RW)
-#define __PAGE_HYPERVISOR_UCMINUS (__PAGE_HYPERVISOR | _PAGE_PCD)
-#define __PAGE_HYPERVISOR_UC (__PAGE_HYPERVISOR | _PAGE_PCD | _PAGE_PWT)
+#define __PAGE_HYPERVISOR_UCMINUS (__PAGE_HYPERVISOR | _PAGE_UCM)
+#define __PAGE_HYPERVISOR_UC (__PAGE_HYPERVISOR | _PAGE_UC)
#define __PAGE_HYPERVISOR_SHSTK (__PAGE_HYPERVISOR_RO | _PAGE_DIRTY)
#define MAP_SMALL_PAGES _PAGE_AVAIL0 /* don't use superpages mappings */
