diff --git a/boot/qemu b/boot/qemu
index 379c53ba..bdb039c4 100755
--- a/boot/qemu
+++ b/boot/qemu
@@ -30,7 +30,7 @@ u9fs="guestfwd=tcp:10.0.2.1:564-cmd:../sys/src/cmd/unix/u9fs/u9fs -a none -u $US
 tftp='tftp=..'
 mac=mac=52:54:00:12:34:56
 
-qemu-system-x86_64 -m 1G -smp 1 -serial stdio \
+qemu-system-x86_64 -m 1G -smp 2 -serial stdio \
 	-drive file=$pxe,format=raw -snapshot \
 	-device virtio-net-pci,netdev=net0,$mac \
 	-netdev "user,id=net0,$u9fs,$tftp"
diff --git a/cfg/pxe/525400123456 b/cfg/pxe/525400123456
index 7bfb4bd6..16491012 100644
--- a/cfg/pxe/525400123456
+++ b/cfg/pxe/525400123456
@@ -28,7 +28,7 @@ fs=10.0.2.1
 auth=10.0.2.1
 sysname=gnot
 *nobiosload=1
-*nomp=1
+#*nomp=1
 partition=new
 factotumopts=-n
 user=glenda
diff --git a/sys/src/9k/k10/mem.h b/sys/src/9k/k10/mem.h
index 3e6d34ed..bb930e48 100644
--- a/sys/src/9k/k10/mem.h
+++ b/sys/src/9k/k10/mem.h
@@ -56,6 +56,7 @@
  */
 #define UTZERO		(0+2*MiB)		/* first address in user text */
 #define UTROUND(t)	ROUNDUP((t), 2*MiB)
+#define UADDRMASK	0x00007fffffffffffull	/* canonical address mask */
 #define USTKTOP		0x00007ffffffff000ull
 #define USTKSIZE	(16*1024*1024)		/* size of user stack */
 #define TSTKTOP		(USTKTOP-USTKSIZE)	/* end of new stack in sysexec */
diff --git a/sys/src/9k/k10/trap.c b/sys/src/9k/k10/trap.c
index 4592a143..8fbc9809 100644
--- a/sys/src/9k/k10/trap.c
+++ b/sys/src/9k/k10/trap.c
@@ -621,24 +621,14 @@ userpc(Ureg* ureg)
 void
 setregisters(Ureg* ureg, char* pureg, char* uva, int n)
 {
-	u64int cs, flags, ss;
-	u16int ds, es, fs, gs;
+	u64int flags;
 
-	ss = ureg->ss;
 	flags = ureg->flags;
-	cs = ureg->cs;
-	gs = ureg->cs;
-	fs = ureg->cs;
-	es = ureg->cs;
-	ds = ureg->cs;
 	memmove(pureg, uva, n);
-	ureg->ds = ds;
-	ureg->es = es;
-	ureg->fs = fs;
-	ureg->gs = gs;
-	ureg->cs = cs;
+	ureg->cs = SSEL(SiUCS, SsTIGDT|SsRPL3);
+	ureg->ss = SSEL(SiUDS, SsTIGDT|SsRPL3);
 	ureg->flags = (ureg->flags & 0x00ff) | (flags & 0xff00);
-	ureg->ss = ss;
+	ureg->ip &= UADDRMASK;
 }
 
 /* Give enough context in the ureg to produce a kernel stack for