5 files changed, 28 insertions, 7 deletions

diff --git a/kernel/cpu/idt.c b/kernel/cpu/idt.c
index 9508f8c..acede33 100644
--- a/kernel/cpu/idt.c
+++ b/kernel/cpu/idt.c
@@ -76,6 +76,13 @@ void page_fault(reg_t *regs) {
     process_pop_restore_context(NULL, regs);
     return;
   }
+
+  int is_userspace = (regs->error_code & (1 << 2));
+  if (is_userspace) {
+    signal_process(current_task, SIGSEGV);
+    return;
+  }
+
   klog("Page Fault", LOG_ERROR);
   kprintf("CR2: %x\n", cr2);
   if (current_task) {
@@ -97,15 +104,11 @@ void page_fault(reg_t *regs) {
     kprintf("read access\n");
   }
 
-  if (regs->error_code & (1 << 2)) {
-    kprintf("CPL = 3\n");
-  }
-
   if (regs->error_code & (1 << 4)) {
     kprintf("Attempted instruction fetch\n");
   }
 
-  dump_backtrace(20);
+  dump_backtrace(15);
   halt();
 }
 
diff --git a/kernel/cpu/isr.s b/kernel/cpu/isr.s
index 8032485..819b22b 100644
--- a/kernel/cpu/isr.s
+++ b/kernel/cpu/isr.s
@@ -11,6 +11,13 @@
     push \num
     jmp isr_common_stub
 .endm
+.macro ISR_ERRCODE num
+  .global isr\num
+  isr\num:
+    cli 
+    push \num
+    jmp isr_common_stub
+.endm
 
 ISR_NOERRCODE 0
 ISR_NOERRCODE 1
@@ -26,7 +33,7 @@ ISR_NOERRCODE 10
 ISR_NOERRCODE 11
 ISR_NOERRCODE 12
 ISR_NOERRCODE 13
-ISR_NOERRCODE 14
+ISR_ERRCODE 14
 ISR_NOERRCODE 15
 ISR_NOERRCODE 16
 ISR_NOERRCODE 17
diff --git a/kernel/includes/signal.h b/kernel/includes/signal.h
index b9ab4a7..6bc9f67 100644
--- a/kernel/includes/signal.h
+++ b/kernel/includes/signal.h
@@ -6,6 +6,7 @@
 #define SIGWINCH 2
 #define SIGQUIT 3
 #define SIG_IGN 4
+#define SIGSEGV 5
 #define SIGTERM 15
 typedef int sigset_t;
 
diff --git a/kernel/sched/scheduler.c b/kernel/sched/scheduler.c
index 423c1b6..57ab33b 100644
--- a/kernel/sched/scheduler.c
+++ b/kernel/sched/scheduler.c
@@ -216,6 +216,7 @@ void free_process(process_t *p) {
 
 void exit_process(process_t *p, int status) {
   disable_interrupts();
+  int killing_itself = (p == current_task);
   assert(p->pid != 1);
   if (p->parent) {
     p->parent->halts[WAIT_CHILD_HALT] = 0;
@@ -246,6 +247,9 @@ void exit_process(process_t *p, int status) {
     }
     tmp = tmp->next;
   }
+  if (killing_itself) {
+    switch_task();
+  }
 }
 
 void exit(int status) {
@@ -474,9 +478,14 @@ void signal_process(process_t *p, int sig) {
     if (SIGTERM == sig) {
       kprintf("HAS NO SIGTERM\n");
       exit_process(p, 1 /*TODO: what should the status be?*/);
+      ASSERT_NOT_REACHED;
+    } else if (SIGSEGV == sig) {
+      kprintf("HAS NO SIGSEGV\n");
+      exit_process(p, 1 /*TODO: what should the status be?*/);
+      ASSERT_NOT_REACHED;
     } else {
       // TODO: Should also exit proess(I think)
-      assert(0);
+      ASSERT_NOT_REACHED;
     }
   }
   signal_t signal = {.handler_ip = (uintptr_t)p->signal_handlers[sig]};
diff --git a/kernel/sched/scheduler.h b/kernel/sched/scheduler.h
index b197117..7e42cc7 100644
--- a/kernel/sched/scheduler.h
+++ b/kernel/sched/scheduler.h
@@ -98,4 +98,5 @@ struct Process {
 int get_task_from_pid(pid_t pid, process_t **out);
 void free_process(process_t *p);
 void *get_free_virtual_memory(size_t length);
+void signal_process(process_t *p, int sig);
 #endif