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;