Changeset 1eb0dd13 in mainline

Timestamp:

2005-07-21T13:32:41Z (20 years ago)

Author:

Jakub Vana <jakub.vana@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

60875800

Parents:

2884193

Message:

Disable alignment check

Files:

• arch/ia32/src/pm.c (modified) (3 diffs)
• doc/TODO (modified) (1 diff)

arch/ia32/src/pm.c

@@ -129 +129 @@
 
 
-
+// Clean IOPL(12,13) and NT(14) flags in EFLAGS register
 static void clean_IOPL_NT_flags(void)
 {
@@ -144 +144 @@
         );
 }
+
+// Clean AM(18) flag in CR0 register
+static void clean_AM_flag(void)
+{
+  asm
+        (
+    "mov %%cr0,%%eax;"
+                "and $0xFFFBFFFF,%%eax;"
+                "mov %%eax,%%cr0;"
+                :
+                :
+                :"%eax"
+        );
+}
+
 
 
@@ -186 +201 @@
         __asm__("ltr %0" : : "r" ((__u16) selector(TSS_DES)));
         
-        clean_IOPL_NT_flags();
-}
+        clean_IOPL_NT_flags();    //Disable I/O on nonprivileged levels 
+        clean_AM_flag();          //Disable alignment check
+}

doc/TODO

@@ -13 +13 @@
   + [ia32] lazy context switch using TS flag                              [DONE]
 + [ia32] MMX,SSE1-.. initialization
-+ [ia32] review privilege separation
++ [ia32] review privilege separation                                      [DONE]
   + zero IOPL in EFLAGS                                                   [DONE]
   + before IRET (from SYSCALL), zero NT in EFLAGS                         [DONE]