commit cb83c71628378bc0e295dd71bf6641379fbcdf37
parent 84eb544b23b17fed07b8c33142d48fdceffce10c
Author: rtm <rtm>
Date: Tue, 13 Jun 2006 22:08:20 +0000
fix some trap bugs
Diffstat:
4 files changed, 26 insertions(+), 6 deletions(-)
diff --git a/Notes b/Notes
@@ -73,3 +73,9 @@ setupsegs() may modify current segment table, is that legal?
trap() ought to lgdt on return, since currently only done in swtch()
protect hardware interrupt vectors from user INT instructions?
+
+i'm getting a curious interrupt when jumping into user space. maybe
+it's IRQ 0, but it comes at a weird and changing vector (e.g. 119) if
+you don't initialize the PIC. why doesn't jos see this? if i
+initialize the PIC with IRQ_OFFSET 32, the interrupt arrives at vector
+32.
diff --git a/main.c b/main.c
@@ -5,12 +5,20 @@
#include "defs.h"
#include "x86.h"
-char junk1[20000];
-char junk2[20000] = { 1 };
+extern char edata[], end[];
main()
{
struct proc *p;
+
+ // clear BSS
+ memset(edata, 0, end - edata);
+
+ // partially initizialize PIC
+ outb(0x20+1, 0xFF); // IO_PIC1
+ outb(0xA0+1, 0xFF); // IO_PIC2
+ outb(0x20, 0x11);
+ outb(0x20+1, 32);
cprintf("\nxV6\n\n");
diff --git a/trap.c b/trap.c
@@ -12,11 +12,15 @@ extern unsigned vectors[]; /* vectors.S, array of 256 entry point addresses */
extern void trapenter();
extern void trapenter1();
+
+int xx;
+
void
tinit()
{
int i;
+ xx = 0;
for(i = 0; i < 256; i++){
SETGATE(idt[i], 1, SEG_KCODE << 3, vectors[i], 3);
}
@@ -27,8 +31,10 @@ void
trap(struct Trapframe *tf)
{
/* which process are we running? */
- cprintf("trap %d tf %x\n", tf->tf_trapno, tf);
- while(1)
- ;
+ if(xx < 10)
+ cprintf("%d\n", tf->tf_trapno);
+ xx++;
+ //while(1)
+ //;
// XXX probably ought to lgdt on trap return
}
diff --git a/vectors.pl b/vectors.pl
@@ -14,7 +14,7 @@ for(my $i = 0; $i < 256; $i++){
if(($i < 8 || $i > 14) && $i != 17){
print "\tpushl \$0\n";
}
- print "\tpushl $i\n";
+ print "\tpushl \$$i\n";
print "\tjmp alltraps\n";
}
print ".data\n";