[PATCH] x86_64: Flexmap for 32bit and randomized mappings for 64bit

Another try at this.

For 32bit follow the 32bit implementation from Ingo -
mappings are growing down from the end of stack now
and vary randomly by 1GB.

Randomized mappings for 64bit just vary the normal mmap break
by 1TB. I didn't bother implementing full flex mmap for 64bit
because it shouldn't be needed there.

Cc: mingo@elte.hu

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 4 insertions, 0 deletions

diff --git a/include/asm-x86_64/ia32.h b/include/asm-x86_64/ia32.h
index c7bc9c0525ba..e6b7f2234e43 100644
--- a/include/asm-x86_64/ia32.h
+++ b/include/asm-x86_64/ia32.h
@@ -169,6 +169,8 @@ int ia32_child_tls(struct task_struct *p, struct pt_regs *childregs);
 struct linux_binprm;
 extern int ia32_setup_arg_pages(struct linux_binprm *bprm,
                                 unsigned long stack_top, int exec_stack);
+struct mm_struct;
+extern void ia32_pick_mmap_layout(struct mm_struct *mm);
 
 #endif
 
diff --git a/include/asm-x86_64/processor.h b/include/asm-x86_64/processor.h
index a1ba7c97465a..8c8d88c036ed 100644
--- a/include/asm-x86_64/processor.h
+++ b/include/asm-x86_64/processor.h
@@ -477,4 +477,6 @@ extern unsigned long boot_option_idle_override;
 /* Boot loader type from the setup header */
 extern int bootloader_type;
 
+#define HAVE_ARCH_PICK_MMAP_LAYOUT 1
+
 #endif /* __ASM_X86_64_PROCESSOR_H */