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Diffstat (limited to 'arch/x86/vdso/vma.c')
-rw-r--r--arch/x86/vdso/vma.c58
1 files changed, 39 insertions, 19 deletions
diff --git a/arch/x86/vdso/vma.c b/arch/x86/vdso/vma.c
index 7abd2be0f9b..316fbca3490 100644
--- a/arch/x86/vdso/vma.c
+++ b/arch/x86/vdso/vma.c
@@ -14,41 +14,61 @@
#include <asm/vgtod.h>
#include <asm/proto.h>
#include <asm/vdso.h>
+#include <asm/page.h>
unsigned int __read_mostly vdso_enabled = 1;
extern char vdso_start[], vdso_end[];
extern unsigned short vdso_sync_cpuid;
-static struct page **vdso_pages;
+extern struct page *vdso_pages[];
static unsigned vdso_size;
-static int __init init_vdso_vars(void)
+static void __init patch_vdso(void *vdso, size_t len)
+{
+ Elf64_Ehdr *hdr = vdso;
+ Elf64_Shdr *sechdrs, *alt_sec = 0;
+ char *secstrings;
+ void *alt_data;
+ int i;
+
+ BUG_ON(len < sizeof(Elf64_Ehdr));
+ BUG_ON(memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0);
+
+ sechdrs = (void *)hdr + hdr->e_shoff;
+ secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
+
+ for (i = 1; i < hdr->e_shnum; i++) {
+ Elf64_Shdr *shdr = &sechdrs[i];
+ if (!strcmp(secstrings + shdr->sh_name, ".altinstructions")) {
+ alt_sec = shdr;
+ goto found;
+ }
+ }
+
+ /* If we get here, it's probably a bug. */
+ pr_warning("patch_vdso: .altinstructions not found\n");
+ return; /* nothing to patch */
+
+found:
+ alt_data = (void *)hdr + alt_sec->sh_offset;
+ apply_alternatives(alt_data, alt_data + alt_sec->sh_size);
+}
+
+static int __init init_vdso(void)
{
int npages = (vdso_end - vdso_start + PAGE_SIZE - 1) / PAGE_SIZE;
int i;
+ patch_vdso(vdso_start, vdso_end - vdso_start);
+
vdso_size = npages << PAGE_SHIFT;
- vdso_pages = kmalloc(sizeof(struct page *) * npages, GFP_KERNEL);
- if (!vdso_pages)
- goto oom;
- for (i = 0; i < npages; i++) {
- struct page *p;
- p = alloc_page(GFP_KERNEL);
- if (!p)
- goto oom;
- vdso_pages[i] = p;
- copy_page(page_address(p), vdso_start + i*PAGE_SIZE);
- }
+ for (i = 0; i < npages; i++)
+ vdso_pages[i] = virt_to_page(vdso_start + i*PAGE_SIZE);
return 0;
-
- oom:
- printk("Cannot allocate vdso\n");
- vdso_enabled = 0;
- return -ENOMEM;
}
-subsys_initcall(init_vdso_vars);
+subsys_initcall(init_vdso);
struct linux_binprm;