1 files changed, 4 insertions, 1 deletions
diff --git a/trap.c b/trap.c
index 89c6bf5..33d7be1 100644
--- a/trap.c
+++ b/trap.c
@@ -29,10 +29,13 @@ void
 trap(struct Trapframe *tf)
 {
   int v = tf->tf_trapno;
+
+  acquire_spinlock(&kernel_lock); // released in trapret in trapasm.S
+
   cprintf("trap %d eip %x:%x\n", tf->tf_trapno, tf->tf_cs, tf->tf_eip);
 
   if(v == T_SYSCALL){
-    curproc->tf = tf;
+    curproc[cpu()]->tf = tf;
     syscall();
     return;
   }