内核模块代码:
static int __init module(void)
{
struct pid *current_pid;
struct task_struct *current_task;
struct mm_struct *mymm;
struct vm_area_struct *pos = NULL;
current_pid = find_vpid(7887);
current_task = pid_task(current_pid, PIDTYPE_PID);
mymm = current_task->mm;
for(pos = mymm->mmap; pos; pos = pos->vm_next) {
printk("0x%hx-0x%hx\t%ld\t", pos->vm_start, pos->vm_end,pos->rb_subtree_gap);
if(pos->vm_flags & VM_READ) {
printk("r");
} else {
printk("-");
}
if(pos->vm_flags & VM_WRITE) {
printk("w");
} else {
printk("-");
}
if(pos->vm_flags & VM_EXEC) {
printk("x");
} else {
printk("-");
}
printk("\n");
}
return 0;
}
static void __exit rmodule(void)
{
printk(KERN_ALERT"Goodbye,world\n");
}
module_init(module);
module_exit(rmodule);
结果:
Oct 9 18:57:43 shui kernel: [14625.861352] 0x400000-0x401000 4194304 r-x
Oct 9 18:57:43 shui kernel: [14625.861366] 0x600000-0x601000 273183399936 r--
Oct 9 18:57:43 shui kernel: [14625.861373] 0x601000-0x602000 0 rw-
Oct 9 18:57:43 shui kernel: [14625.861379] 0x3f9b600000-0x3f9b620000 273183399936 r-x
Oct 9 18:57:43 shui kernel: [14625.861386] 0x3f9b820000-0x3f9b821000 140214666838016 r--
Oct 9 18:57:43 shui kernel: [14625.861391] 0x3f9b821000-0x3f9b822000 0 rw-
Oct 9 18:57:43 shui kernel: [14625.861397] 0x3f9b822000-0x3f9b823000 0 rw-
Oct 9 18:57:43 shui kernel: [14625.861403] 0x3f9ba00000-0x3f9bbad000 1953792 r-x
Oct 9 18:57:43 shui kernel: [14625.861408] 0x3f9bbad000-0x3f9bdad000 0 ---
Oct 9 18:57:43 shui kernel: [14625.861414] 0x3f9bdad000-0x3f9bdb1000 140214666838016 r--
Oct 9 18:57:43 shui kernel: [14625.861419] 0x3f9bdb1000-0x3f9bdb3000 0 rw-
Oct 9 18:57:43 shui kernel: [14625.861425] 0x3f9bdb3000-0x3f9bdb8000 140214666838016 rw-
Oct 9 18:57:43 shui kernel: [14625.861431] 0x7fc5e1444000-0x7fc5e1447000 140214666838016 rw-
Oct 9 18:57:43 shui kernel: [14625.861436] 0x7fc5e146f000-0x7fc5e1470000 140214666838016 rw-
Oct 9 18:57:43 shui kernel: [14625.861442] 0x7fffe4c32000-0x7fffe4c54000 249166569472 rw-
Oct 9 18:57:43 shui kernel: [14625.861448] 0x7fffe4d79000-0x7fffe4d7b000 1200128 r-x
但使用 cat/proc/7887/maps:
shui @ kernel @ 19:00]$ cat /proc/7887/maps
00400000-00401000 r-xp 00000000 00:20 1826951 /tmp/a.out
00600000-00601000 r--p 00000000 00:20 1826951 /tmp/a.out
00601000-00602000 rw-p 00001000 00:20 1826951 /tmp/a.out
3f9b600000-3f9b620000 r-xp 00000000 fd:01 2228400 /usr/lib64
/ld-2.16.so
3f9b820000-3f9b821000 r--p 00020000 fd:01 2228400 /usr/lib64/ld-2.16.so
3f9b821000-3f9b822000 rw-p 00021000 fd:01 2228400 /usr/lib64/ld-2.16.so
3f9b822000-3f9b823000 rw-p 00000000 00:00 0
3f9ba00000-3f9bbad000 r-xp 00000000 fd:01 2228403 /usr/lib64/libc-2.16.so
3f9bbad000-3f9bdad000 ---p 001ad000 fd:01 2228403 /usr/lib64/libc-2.16.so
3f9bdad000-3f9bdb1000 r--p 001ad000 fd:01 2228403 /usr/lib64/libc-2.16.so
3f9bdb1000-3f9bdb3000 rw-p 001b1000 fd:01 2228403 /usr/lib64/libc-2.16.so
3f9bdb3000-3f9bdb8000 rw-p 00000000 00:00 0
7fc5e1444000-7fc5e1447000 rw-p 00000000 00:00 0
7fc5e146f000-7fc5e1470000 rw-p 00000000 00:00 0
7fffe4c33000-7fffe4c54000 rw-p 00000000 00:00 0 [stack]
7fffe4d79000-7fffe4d7b000 r-xp 00000000 00:00 0 [vdso]
ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0 [vsyscall]
关于堆栈地址的vm_area_struct是7fffe4c32000，但是映射是7fffe4c33000，这有什么不同？ vsyscall 是为什么不在 vm_area_struct 上打印？
最佳答案
这是正常的，Linux 内核使用堆栈保护，procfs 不显示页面。
查看fs/proc/task_mmu.c中的函数show_map_vma
关于c - 关于/proc/xx/map 和 vm_area_struct，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/26277134/