Fix aborts on Cortex-A15 when using lazy task swapping

Detail:
  s/VMSAv6 - After AMB_LazyFixUp has modified the page tables, perform a DSB + ISB to ensure the page table write has completed before we return from the abort handler.
Admin:
  Tested on IGEPv5
  Fixes aborts seen in desktop, e.g. when !CloseUp is rebuilding its sprite (heavy RAM write activity delaying pagetable write?)


Version 5.35, 4.79.2.262. Tagged as 'Kernel-5_35-4_79_2_262'

VersionASM

@@ -13,11 +13,11 @@
                         GBLS    Module_ComponentPath
 Module_MajorVersion     SETS    "5.35"
 Module_Version          SETA    535
-Module_MinorVersion     SETS    "4.79.2.261"
-Module_Date             SETS    "29 Mar 2015"
-Module_ApplicationDate  SETS    "29-Mar-15"
+Module_MinorVersion     SETS    "4.79.2.262"
+Module_Date             SETS    "13 Apr 2015"
+Module_ApplicationDate  SETS    "13-Apr-15"
 Module_ComponentName    SETS    "Kernel"
 Module_ComponentPath    SETS    "castle/RiscOS/Sources/Kernel"
-Module_FullVersion      SETS    "5.35 (4.79.2.261)"
-Module_HelpVersion      SETS    "5.35 (29 Mar 2015) 4.79.2.261"
+Module_FullVersion      SETS    "5.35 (4.79.2.262)"
+Module_HelpVersion      SETS    "5.35 (13 Apr 2015) 4.79.2.262"
                         END

VersionNum

@@ -5,19 +5,19 @@
  *
  */
 #define Module_MajorVersion_CMHG        5.35
-#define Module_MinorVersion_CMHG        4.79.2.261
-#define Module_Date_CMHG                29 Mar 2015
+#define Module_MinorVersion_CMHG        4.79.2.262
+#define Module_Date_CMHG                13 Apr 2015
 
 #define Module_MajorVersion             "5.35"
 #define Module_Version                  535
-#define Module_MinorVersion             "4.79.2.261"
-#define Module_Date                     "29 Mar 2015"
+#define Module_MinorVersion             "4.79.2.262"
+#define Module_Date                     "13 Apr 2015"
 
-#define Module_ApplicationDate          "29-Mar-15"
+#define Module_ApplicationDate          "13-Apr-15"
 
 #define Module_ComponentName            "Kernel"
 #define Module_ComponentPath            "castle/RiscOS/Sources/Kernel"
 
-#define Module_FullVersion              "5.35 (4.79.2.261)"
-#define Module_HelpVersion              "5.35 (29 Mar 2015) 4.79.2.261"
+#define Module_FullVersion              "5.35 (4.79.2.262)"
+#define Module_HelpVersion              "5.35 (13 Apr 2015) 4.79.2.262"
 #define Module_LibraryVersionInfo       "5:35"

s/VMSAv6

@@ -497,6 +497,10 @@ PAbPreVeneer    ROUT
         SUB     r0, lr_abort, #4          ; aborting address
         MOV     r2, #1
         BL      AMB_LazyFixUp             ; can trash r0-r7, returns NE status if claimed and fixed up
+        ; DSB + ISB required to ensure effect of page table write is fully
+        ; visible (after overwriting a faulting entry)
+        myDSB   NE,r0
+        myISB   NE,r0,,y
         Pull    "r0-r7, lr", NE           ; restore regs and
         SUBNES  pc, lr_abort, #4          ; restart aborting instruction if fixed up
         LDR     lr, [sp, #8*4]            ; (not a lazy abort) restore lr
@@ -570,6 +574,10 @@ DAbPreVeneer    ROUT
         ARM_read_FAR r0                         ; aborting address
         MOV     r2, #0
         BL      AMB_LazyFixUp                   ; can trash r0-r7, returns NE status if claimed and fixed up
+        ; DSB + ISB required to ensure effect of page table write is fully
+        ; visible (after overwriting a faulting entry)
+        myDSB   NE,r0
+        myISB   NE,r0,,y
         LDR     lr_abort, [r13_abort, #15*4]    ; restore lr_abort
         LDMIA   r13_abort, {r0-r7}              ; restore regs
         ADDNE   r13_abort, r13_abort, #17*4     ; if fixed up, restore r13_abort