Changeset 46c20c8 in mainline for kernel/arch/amd64/src/syscall.c

Timestamp:

2010-11-26T20:08:10Z (15 years ago)

Author:

Jiri Svoboda <jiri@…>

Branches:

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

Children:

45df59a

Parents:

fb150d78 (diff), ffdd2b9 (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge mainline changes.

File:

• kernel/arch/amd64/src/syscall.c (modified) (2 diffs)

kernel/arch/amd64/src/syscall.c

@@ -58 +58 @@
          */
         write_msr(AMD_MSR_STAR,
-            ((uint64_t)(gdtselector(KDATA_DES) | PL_USER) << 48) |
-            ((uint64_t)(gdtselector(KTEXT_DES) | PL_KERNEL) << 32));
+            ((uint64_t) (GDT_SELECTOR(KDATA_DES) | PL_USER) << 48) |
+            ((uint64_t) (GDT_SELECTOR(KTEXT_DES) | PL_KERNEL) << 32));
         write_msr(AMD_MSR_LSTAR, (uint64_t)syscall_entry);
         /* Mask RFLAGS on syscall 
@@ -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);
 }