simplify kernel mapping calls

1 files changed, 12 insertions, 6 deletions

diff --git a/kernel/proc.c b/kernel/proc.c
index cebef1a..5ce31c7 100644
--- a/kernel/proc.c
+++ b/kernel/proc.c
@@ -28,12 +28,18 @@ procinit(void)
   initlock(&pid_lock, "nextpid");
   for(p = proc; p < &proc[NPROC]; p++) {
       initlock(&p->lock, "proc");
-      // Allocate a page for the kernel stack.
-      uint64 kstack = KSTACK((int) (p - proc));
-      if((p->kstack = mapkstack(kstack)) == 0) {
-        panic("procinit");
-      }
+
+      // Allocate a page for the process's kernel stack.
+      // Map it high in memory, followed by an invalid
+      // guard page.
+      char *pa = kalloc();
+      if(pa == 0)
+        panic("kalloc");
+      uint64 va = KSTACK((int) (p - proc));
+      kmap(va, (uint64)pa, PGSIZE, PTE_R | PTE_W);
+      p->kstack = va;
   }
+  kvminithart();
 }
 
 // Must be called with interrupts disabled,
@@ -113,7 +119,7 @@ found:
   // which returns to user space.
   memset(&p->context, 0, sizeof p->context);
   p->context.ra = (uint64)forkret;
-  p->context.sp = (uint64)p->kstack + PGSIZE;
+  p->context.sp = p->kstack + PGSIZE;
 
   return p;
 }