Zero the instruction counter on Pentium's after detecting one if we have

NTP code compiled in; prevents division errors in microtime()

diff --git a/sys/arch/i386/i386/locore.s b/sys/arch/i386/i386/locore.s
index 9d6eb17..bd1ca34 100644 (file)
--- a/sys/arch/i386/i386/locore.s
+++ b/sys/arch/i386/i386/locore.s
@@ -437,6 +437,13 @@ try586:    /* Use the `cpuid' instruction. */
        jb      is486                   # less than a Pentium
        movl    $CPU_586,RELOC(_cpu)
 
+#ifdef NTP
+       xorl %eax,%eax
+       xorl %edx,%edx
+       movl $10,%ecx
+       .byte 0xf, 0x30                 # wrmsr (or trap on non-pentium :-)
+#endif
+
 2:
        /*
         * Finished with old stack; load new %esp now instead of later so we