--- /n/sources/plan9/sys/src/9/port/taslock.c	Mon Apr  8 18:18:51 2013
+++ /sys/src/9/port/taslock.c	Sun Feb 28 00:00:00 2016
@@ -80,6 +80,7 @@
 		l->pc = pc;
 		l->p = up;
 		l->isilock = 0;
+		l->m = MACHP(m->machno);
 #ifdef LOCKCYCLES
 		l->lockcycles = -lcycles();
 #endif
@@ -115,6 +116,7 @@
 			l->pc = pc;
 			l->p = up;
 			l->isilock = 0;
+			l->m = MACHP(m->machno);
 #ifdef LOCKCYCLES
 			l->lockcycles = -lcycles();
 #endif