[Midnightbsd-cvs] src: smp.4: We don't support the alpha.

[laffer1 at midnightbsd.org]

Log Message:
-----------
We don't support the alpha.  Also briefly mention the cache related security issues with hyperthreading so users can make a wise decision.

Modified Files:
--------------
    src/share/man/man4:
        smp.4 (r1.1.1.1 -> r1.2)

-------------- next part --------------
Index: smp.4
===================================================================
RCS file: /home/cvs/src/share/man/man4/smp.4,v
retrieving revision 1.1.1.1
retrieving revision 1.2
diff -L share/man/man4/smp.4 -L share/man/man4/smp.4 -u -r1.1.1.1 -r1.2
--- share/man/man4/smp.4
+++ share/man/man4/smp.4
@@ -21,14 +21,15 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
+.\" $MIdnightBSD$
 .\" $FreeBSD: src/share/man/man4/smp.4,v 1.21 2004/12/18 01:13:37 jkoshy Exp $
 .\"
-.Dd December 17, 2004
+.Dd April 28, 2008
 .Dt SMP 4
 .Os
 .Sh NAME
 .Nm SMP
-.Nd description of the FreeBSD Symmetric Multi-Processor kernel
+.Nd description of the MidnightBSD Symmetric Multi-Processor kernel
 .Sh SYNOPSIS
 .Cd options SMP
 .Sh DESCRIPTION
@@ -38,8 +39,8 @@
 .Sh COMPATIBILITY
 Support for multi-processor systems is present for all Tier-1
 architectures on
-.Fx .
-Currently, this includes alpha, amd64, i386, ia64, and sparc64.
+.Mx .
+Currently, this includes amd64, i386, and sparc64.
 Support is enabled using
 .Cd options SMP .
 It is permissible to use the SMP kernel configuration on non-SMP equipped
@@ -74,7 +75,9 @@
 Since using logical CPUs can cause performance penalties under certain loads,
 the logical CPUs can be disabled by setting the
 .Va machdep.hlt_logical_cpus
-sysctl to one.
+sysctl to one. There are also security implications to running
+hyperthreading; it is possible to access shared information in
+the CPU cache although not easy to exploit.
 .Sh SEE ALSO
 .Xr mptable 1 ,
 .Xr sysctl 8 ,
@@ -105,5 +108,9 @@
 .Pp
 .Fx 5.0
 also introduced support for SMP on the alpha, ia64, and sparc64 architectures.
+.Mx 0.2
+removed support for the alpha.
+
 .Sh AUTHORS
 .An Steve Passe Aq fsmp at FreeBSD.org
+.Ah Lucas Holt Aq luke at midnightbsd.org