From: AceVest <zhaoyanbai@126.com>
Date: Thu, 31 Jul 2014 15:20:11 +0000 (+0800)
Subject: fix write protection bug when fork
X-Git-Tag: 0.3.0~5
X-Git-Url: http://zhaoyanbai.com/repos/%22http:/www.isc.org/icons/zlib_tech.html?a=commitdiff_plain;h=523942d07ca683682551e66dc7fe4f15dbf636dc;p=kernel.git

fix write protection bug when fork
---

diff --git a/kernel/exec.c b/kernel/exec.c
index d6ffd26..8732ff9 100644
--- a/kernel/exec.c
+++ b/kernel/exec.c
@@ -67,8 +67,6 @@ int sysc_exec(const char *path, char *const argv[])
     assert(strncmp(ELFMAG, ehdr->e_ident, sizeof(ELFMAG)-1) == 0);
     printk("Elf Entry: %08x\n", ehdr->e_entry);
 
-
-
     int i, j;
     for(i=0; i<ehdr->e_phnum; ++i)
     {
@@ -109,6 +107,7 @@ int sysc_exec(const char *path, char *const argv[])
         }
     }
 
+
     load_cr3(current);
 
     disable_irq();
@@ -127,7 +126,7 @@ int sysc_exec(const char *path, char *const argv[])
 #endif
     regs->eip   = (unsigned long)ehdr->e_entry;
     regs->edx   = regs->eip;
-    regs->ecx   = (0xC0000000 - 16);
+    regs->ecx   = KRNLADDR; //(0xC0000000 - 16);
 
     //kfree(buf);
 
diff --git a/kernel/fork.c b/kernel/fork.c
index 57d67bc..968b75f 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -94,6 +94,8 @@ int do_fork(pt_regs_t *regs, unsigned long flags)
         }
     //}
 
+    load_cr3(current);
+
     tsk->pid    = get_next_pid();
     tsk->ppid   = current->pid;
 
diff --git a/kernel/innerint.c b/kernel/innerint.c
index 77feb17..7e064e8 100644
--- a/kernel/innerint.c
+++ b/kernel/innerint.c
@@ -104,7 +104,7 @@ US RW  P - Description
 
     asm("movl %%cr2,%%eax":"=a"(addr));
 
-    printk("do page fault errcode %x addr %08x [%08x]\n", errcode, addr, current);
+    //printk("do page fault errcode %x addr %08x [%08x]\n", errcode, addr, current);
 
     //assert(errcode != 2 && errcode != 6);
 
diff --git a/kernel/sched.c b/kernel/sched.c
index d5626e0..381c098 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -183,7 +183,6 @@ unsigned long schedule()
 
     if(prev != next)
     {
-        printd("[s:%08x]\n", next);
         context_switch(prev, next);
     }
 }
diff --git a/lib/libc.S b/lib/libc.S
index f4e14e2..ea20738 100644
--- a/lib/libc.S
+++ b/lib/libc.S
@@ -24,9 +24,9 @@ loop:
     jmp loop
     */
 
-    pushl   $0  # env
-    pushl   $0  # argv
-    pushl   $1  # argc
+
+    pushl   $0xAAAAAAAA
+    pushl   $0x11111111
 
     call main
 
diff --git a/lib/syscall.c b/lib/syscall.c
index 7ca1420..c4a2276 100644
--- a/lib/syscall.c
+++ b/lib/syscall.c
@@ -18,35 +18,35 @@
         "sysenter;"             \
         "1:"
 
-static int __syscall0(int nr)
+static int  __volatile__ __syscall0(int nr)
 {
     int __sysc_ret__ = 0;
     asm(SYSENTER_ASM:"=a"(__sysc_ret__):"a"(nr));
     return __sysc_ret__;
 }
 
-static int __syscall1(int nr, unsigned long a)
+static int __volatile__ __syscall1(int nr, unsigned long a)
 {
     int __sysc_ret__ = 0;
     asm(SYSENTER_ASM:"=a"(__sysc_ret__):"a"(nr), "b"(a));
     return __sysc_ret__;
 }
 
-static int __syscall2(int nr, unsigned long a, unsigned long b)
+static int __volatile__ __syscall2(int nr, unsigned long a, unsigned long b)
 {
     int __sysc_ret__ = 0;
     asm(SYSENTER_ASM:"=a"(__sysc_ret__):"a"(nr), "b"(a), "c"(b));
     return __sysc_ret__;
 }
 
-static int __syscall3(int nr, unsigned long a, unsigned long b, unsigned long c)
+static int __volatile__ __syscall3(int nr, unsigned long a, unsigned long b, unsigned long c)
 {
     int __sysc_ret__ = 0;
     asm(SYSENTER_ASM:"=a"(__sysc_ret__):"a"(nr), "b"(a), "c"(b), "d"(c));
     return __sysc_ret__;
 }
 
-static int __syscall4(int nr, unsigned long a, unsigned long b, unsigned long c, unsigned long d)
+static int __volatile__ __syscall4(int nr, unsigned long a, unsigned long b, unsigned long c, unsigned long d)
 {
     int __sysc_ret__ = 0;
     asm(SYSENTER_ASM:"=a"(__sysc_ret__):"a"(nr), "b"(a), "c"(b), "d"(c), "S"(d));