# HG changeset patch
# User John Tsiombikas <nuclear@member.fsf.org>
# Date 1312000553 -10800
# Node ID 1d8877d12de09ef9f3b433ffc9248262811df05a
# Parent  50730d42d2d3d8eb80b3eb37e6f94ca8c33d0644
tidyed up the intr_ret bit, made it a bit more reasonably structured, and cleaned up some debugging things

diff -r 50730d42d2d3 -r 1d8877d12de0 src/intr-asm.S
--- a/src/intr-asm.S	Sat Jul 30 07:21:54 2011 +0300
+++ b/src/intr-asm.S	Sat Jul 30 07:35:53 2011 +0300
@@ -70,20 +70,26 @@
 intr_entry_common:
 	pusha
 	call dispatch_intr
-	jmp 0f
-
-	.globl intr_ret
-intr_ret:
-	/* if called as a function from context_switch, we must
-	 * remove the pushed return address before continuing
-     */
-	add $4, %esp
-0:	/* ... we skip to here otherwise */
+intr_ret_local:
 	popa
 	/* remove error code and intr num from stack */
 	add $8, %esp
 	iret
 
+/* intr_ret is called by context_switch to return from the kernel
+ * to userspace. The argument is a properly formed intr_frame
+ * structure with the saved context of the new task.
+ *
+ * First thing to do is remove the return address pointing back
+ * to context_switch, which then leaves us with a proper interrupt
+ * stack frame, so we can jump right in the middle of the regular
+ * interrupt return code above.
+ */
+	.globl intr_ret
+intr_ret:
+	add $4, %esp
+	jmp intr_ret_local
+
 /* by including interrupts.h with ASM defined, the macros above
  * are expanded to generate all required interrupt entry points
  */
diff -r 50730d42d2d3 -r 1d8877d12de0 src/proc.c
--- a/src/proc.c	Sat Jul 30 07:21:54 2011 +0300
+++ b/src/proc.c	Sat Jul 30 07:35:53 2011 +0300
@@ -78,14 +78,6 @@
 	ifrm.regs = ctx->regs;
 	ifrm.eflags = ctx->flags;
 
-	ifrm.err = 0xbadf00d;
-
-	asm volatile (
-		"pushf\n\t"
-		"popl %0\n\t"
-		: "=a" (ifrm.eflags)
-	);
-
 	ifrm.eip = ctx->instr_ptr;
 	ifrm.cs = selector(SEGM_KCODE, 0);	/* XXX change this when we setup the TSS */
 	ifrm.esp = 0;/*ctx->stack_ptr;			/* this will only be used when we switch to userspace */