x86 vDSO: consolidate vdso32
This makes x86_64's ia32 emulation support share the sources used in the
32-bit kernel for the 32-bit vDSO and much of its setup code.
The 32-bit vDSO mapping now behaves the same on x86_64 as on native 32-bit.
The abi.syscall32 sysctl on x86_64 now takes the same values that
vm.vdso_enabled takes on the 32-bit kernel. That is, 1 means a randomized
vDSO location, 2 means the fixed old address. The CONFIG_COMPAT_VDSO
option is now available to make this the default setting, the same meaning
it has for the 32-bit kernel. (This does not affect the 64-bit vDSO.)
The argument vdso32=[012] can be used on both 32-bit and 64-bit kernels to
set this paramter at boot time. The vdso=[012] argument still does this
same thing on the 32-bit kernel.
Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/include/asm-x86/elf.h b/include/asm-x86/elf.h
index 70edff2..60f5101 100644
--- a/include/asm-x86/elf.h
+++ b/include/asm-x86/elf.h
@@ -74,17 +74,19 @@
#ifdef __KERNEL__
+/*
+ * This is used to ensure we don't load something for the wrong architecture.
+ */
+#define elf_check_arch_ia32(x) \
+ (((x)->e_machine == EM_386) || ((x)->e_machine == EM_486))
+
#ifdef CONFIG_X86_32
#include <asm/processor.h>
#include <asm/system.h> /* for savesegment */
#include <asm/desc.h>
#include <asm/vdso.h>
-/*
- * This is used to ensure we don't load something for the wrong architecture.
- */
-#define elf_check_arch(x) \
- (((x)->e_machine == EM_386) || ((x)->e_machine == EM_486))
+#define elf_check_arch(x) elf_check_arch_ia32(x)
/* SVR4/i386 ABI (pages 3-31, 3-32) says that when the program starts %edx
contains a pointer to a function which might be registered using `atexit'.
@@ -247,10 +249,6 @@
#define ELF_CORE_XFPREG_TYPE NT_PRXFPREG
#define VDSO_HIGH_BASE (__fix_to_virt(FIX_VDSO))
-#define VDSO_CURRENT_BASE ((unsigned long)current->mm->context.vdso)
-
-#define VDSO_ENTRY \
- ((unsigned long) VDSO32_SYMBOL(VDSO_CURRENT_BASE, vsyscall))
/* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */
@@ -262,6 +260,8 @@
#else /* CONFIG_X86_32 */
+#define VDSO_HIGH_BASE 0xffffe000U /* CONFIG_COMPAT_VDSO address */
+
/* 1GB for 64bit, 8MB for 32bit */
#define STACK_RND_MASK (test_thread_flag(TIF_IA32) ? 0x7ff : 0x3fffff)
@@ -272,6 +272,11 @@
#endif /* !CONFIG_X86_32 */
+#define VDSO_CURRENT_BASE ((unsigned long)current->mm->context.vdso)
+
+#define VDSO_ENTRY \
+ ((unsigned long) VDSO32_SYMBOL(VDSO_CURRENT_BASE, vsyscall))
+
struct linux_binprm;
#define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1