Changeset 80c9416 in mainline

Timestamp:

2010-07-13T10:42:44Z (14 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

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

Children:

246f939

Parents:

0cd21bf

Message:

Clear RFLAGS_NT upon entering syscall_entry.

Location:

kernel/arch/amd64

Files:

• include/cpu.h (modified) (1 diff)
• src/syscall.c (modified) (1 diff)

kernel/arch/amd64/include/cpu.h

@@ -45 +45 @@
 #define RFLAGS_DF       (1 << 10)
 #define RFLAGS_OF       (1 << 11)
+#define RFLAGS_NT       (1 << 14)
 #define RFLAGS_RF       (1 << 16)
 

kernel/arch/amd64/src/syscall.c

@@ -66 +66 @@
          * - clear DF so that the string instructions operate in
          *   the right direction
+         * - clear NT to prevent a #GP should the flag proliferate to an IRET
          */
-        write_msr(AMD_MSR_SFMASK, RFLAGS_IF | RFLAGS_DF);
+        write_msr(AMD_MSR_SFMASK, RFLAGS_IF | RFLAGS_DF | RFLAGS_NT);
 }