c - 如何在 Linux 内核模块中分配可执行页面？

Question

我正在编写一个 Linux 内核模块，我想分配一个可执行页面。Plainkmalloc()在一个不可执行的页面中返回一个指针，当在那里执行代码时我得到一个内核恐慌。它必须在 Ubuntu Karmic x86、2.6.31-20-generic-pae 上工作。

Answer 1

#include <linux/vmalloc.h>
#include <asm/pgtype_types.h>
...
char *p = __vmalloc(byte_size, GFP_KERNEL, PAGE_KERNEL_EXEC);
...
if (p != NULL) vfree(p);

Answer 2

/**
 * vmalloc_exec - allocate virtually contiguous, executable memory
 * @size:     allocation size
 *
 * Kernel-internal function to allocate enough pages to cover @size
 * the page level allocator and map them into contiguous and
 * executable kernel virtual space.
 *
 * For tight control over page level allocator and protection flags
 * use __vmalloc() instead.
 *
 * Return: pointer to the allocated memory or %NULL on error
 */
void *vmalloc_exec(unsigned long size)
{
    return __vmalloc_node(size, 1, GFP_KERNEL, PAGE_KERNEL_EXEC,
                  NUMA_NO_NODE, __builtin_return_address(0));
}