Changeset 12593 in vbox

Timestamp:

Sep 19, 2008 9:44:35 AM (16 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

36829

Message:

Some comments about DR7.

File:

• trunk/src/VBox/VMM/VMMR0/CPUMR0.cpp (modified) (2 diffs)

trunk/src/VBox/VMM/VMMR0/CPUMR0.cpp

@@ -294 +294 @@
         pCtx->dr6 = ASMGetDR6();
 
-    /* Restore the host's debug state. DR0-3, DR6 and only then DR7! */
+    /* Restore the host's debug state. DR0-3, DR6 and only then DR7! 
+     * DR7 contains 0x400 right now.
+     */
     ASMSetDR0(pVM->cpum.s.Host.dr0);
     ASMSetDR1(pVM->cpum.s.Host.dr1);
@@ -323 +325 @@
     pVM->cpum.s.Host.dr3 = ASMGetDR3();
     pVM->cpum.s.Host.dr6 = ASMGetDR6();
+    /* @todo dr7 might already have been changed to 0x400; don't care right now as it's harmless. */
     pVM->cpum.s.Host.dr7 = ASMGetDR7();
     /* Make sure DR7 is harmless or else we could trigger breakpoints when restoring dr0-3 (!) */