From 5a967402a2c4f68846fdaff8c8d6b4f9b5e44650 Mon Sep 17 00:00:00 2001
From: hinus <hinus@163.com>
Date: Wed, 9 Jun 2021 23:37:03 +0800
Subject: [PATCH] Title: Set 'esp' register Issue:
 https://gitee.com/hinus/linux_kernel_011/issues/I3V35G Description: Set 'esp'
 register, make it point to user_stack.

---
 Makefile        | 70 ++++++++++++++++++++++++-------------------------
 kernel/Makefile | 11 +++++---
 kernel/head.S   |  1 +
 kernel/main.c   |  9 ++++++-
 kernel/sched.c  | 10 +++++++
 5 files changed, 61 insertions(+), 40 deletions(-)
 create mode 100644 kernel/sched.c

diff --git a/Makefile b/Makefile
index c8f6439..99cfe01 100644
--- a/Makefile
+++ b/Makefile
@@ -1,35 +1,35 @@
-AS := as
-LD := ld -m elf_x86_64
-
-LDFLAG := -Ttext 0x0 -s --oformat binary
-
-image : linux.img
-
-linux.img : tools/build bootsect setup kernel/system
-	./tools/build bootsect setup kernel/system > $@
-
-tools/build : tools/build.c
-		gcc -o $@ $<
-
-kernel/system : 
-		cd kernel; make system; cd ..
-
-bootsect : bootsect.o
-	$(LD) $(LDFLAG) -o $@ $<
-
-bootsect.o : bootsect.S
-	$(AS) -o $@ $<
-
-setup : setup.o
-		$(LD) $(LDFLAG) -e _start_setup -o $@ $<
-
-setup.o : setup.S
-		$(AS) -o $@ $<
-clean:
-	rm *.o
-	rm bootsect
-	rm setup
-	rm tools/build
-	rm linux.img
-	cd kernel; make clean; cd ..
-
+AS := as
+LD := ld -m elf_x86_64
+
+LDFLAG := -Ttext 0x0 -s --oformat binary
+
+image : linux.img
+
+linux.img : tools/build bootsect setup kernel/system
+	./tools/build bootsect setup kernel/system > $@
+
+tools/build : tools/build.c
+		gcc -o $@ $<
+
+kernel/system : kernel/head.S kernel/*.c
+		cd kernel; make system; cd ..
+
+bootsect : bootsect.o
+	$(LD) $(LDFLAG) -o $@ $<
+
+bootsect.o : bootsect.S
+	$(AS) -o $@ $<
+
+setup : setup.o
+		$(LD) $(LDFLAG) -e _start_setup -o $@ $<
+
+setup.o : setup.S
+		$(AS) -o $@ $<
+clean:
+	rm *.o
+	rm bootsect
+	rm setup
+	rm tools/build
+	rm linux.img
+	cd kernel; make clean; cd ..
+
diff --git a/kernel/Makefile b/kernel/Makefile
index 59e0061..2f1973f 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -1,18 +1,21 @@
 GCC := gcc
-CCFLAG := -I../include -nostdinc -Wall -fomit-frame-pointer -c 
-LDFLAG := -Ttext 0x0 -s --oformat binary -m elf_x86_64
+CCFLAG := -I../include -nostdinc -Wall -fomit-frame-pointer -c -m32
+LDFLAG := -Ttext 0x0 -s --oformat binary -m elf_i386
 INCDIR := ../include
-OBJS   := head.o main.o
+OBJS   := head.o main.o sched.o
 
 system: $(OBJS)
 	$(LD) $(LDFLAG) -e startup_32 -o $@ $^
 
 head.o : head.S
-	$(GCC) -traditional -c -o $@ $<
+	$(GCC) -m32 -traditional -c -o $@ $<
 
 main.o : main.c
 	$(GCC) $(CCFLAG) -o $@ $<
 
+sched.o : sched.c
+	$(GCC) $(CCFLAG) -o $@ $<
+
 clean : 
 	rm *.o
 	rm system
diff --git a/kernel/head.S b/kernel/head.S
index 077f7c5..4f74b18 100644
--- a/kernel/head.S
+++ b/kernel/head.S
@@ -9,6 +9,7 @@ startup_32:
     movw %ax,   %fs
     movw %ax,   %gs
 
+    lss  stack_start, %esp
     call setup_idt
     call setup_gdt
 
diff --git a/kernel/main.c b/kernel/main.c
index 2e4356f..014708a 100644
--- a/kernel/main.c
+++ b/kernel/main.c
@@ -2,7 +2,14 @@
 
 void main(void) 
 {
-    __asm__("int $0x80 \n\r"::);
+    char* p1 = "hello world!\0";
+    short* p = (short*)0xb8000;
+    while(*p1) {
+        *p++ = 0xf00 | (*p1++);
+    }
+
+    __asm__("int $0x80\n\r"::);
+
     __asm__ __volatile__(
             "loop:\n\r"
             "jmp loop"
diff --git a/kernel/sched.c b/kernel/sched.c
new file mode 100644
index 0000000..97a9e99
--- /dev/null
+++ b/kernel/sched.c
@@ -0,0 +1,10 @@
+#define PAGE_SIZE 4096
+
+long user_stack[PAGE_SIZE >> 2];
+
+struct
+{
+    long *a;
+    short b;
+} stack_start = {&user_stack[PAGE_SIZE >> 2], 0x10};
+
-- 
Gitee