[PATCH] Fix CONFIG_COMPAT_VDSO
I wouldn't mind if CONFIG_COMPAT_VDSO went away entirely. But if it's there,
it should work properly. Currently it's quite haphazard: both real vma and
fixmap are mapped, both are put in the two different AT_* slots, sysenter
returns to the vma address rather than the fixmap address, and core dumps yet
are another story.
This patch makes CONFIG_COMPAT_VDSO disable the real vma and use the fixmap
area consistently. This makes it actually compatible with what the old vdso
implementation did.
Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/asm-i386/elf.h b/include/asm-i386/elf.h
index 45d21a0..0515d61 100644
--- a/include/asm-i386/elf.h
+++ b/include/asm-i386/elf.h
@@ -143,11 +143,8 @@
# define VDSO_PRELINK 0
#endif
-#define VDSO_COMPAT_SYM(x) \
- (VDSO_COMPAT_BASE + (unsigned long)(x) - VDSO_PRELINK)
-
#define VDSO_SYM(x) \
- (VDSO_BASE + (unsigned long)(x) - VDSO_PRELINK)
+ (VDSO_COMPAT_BASE + (unsigned long)(x) - VDSO_PRELINK)
#define VDSO_HIGH_EHDR ((const struct elfhdr *) VDSO_HIGH_BASE)
#define VDSO_EHDR ((const struct elfhdr *) VDSO_COMPAT_BASE)
@@ -156,10 +153,12 @@
#define VDSO_ENTRY VDSO_SYM(&__kernel_vsyscall)
+#ifndef CONFIG_COMPAT_VDSO
#define ARCH_HAS_SETUP_ADDITIONAL_PAGES
struct linux_binprm;
extern int arch_setup_additional_pages(struct linux_binprm *bprm,
int executable_stack);
+#endif
extern unsigned int vdso_enabled;