From 13fca640bb8ab611a50e0ba120b186faa2994d6c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Wed, 15 Jun 2011 21:53:52 -0700 Subject: [PATCH] Revert "fs/exec.c: use BUILD_BUG_ON for VM_STACK_FLAGS & VM_STACK_INCOMPLETE_SETUP" This reverts commit 7f81c8890c15a10f5220bebae3b6dfae4961962a. It turns out that it's not actually a build-time check on x86-64 UML, which does some seriously crazy stuff with VM_STACK_FLAGS. The VM_STACK_FLAGS define depends on the arch-supplied VM_STACK_DEFAULT_FLAGS value, and on x86-64 UML we have arch/um/sys-x86_64/shared/sysdep/vm-flags.h: #define VM_STACK_DEFAULT_FLAGS \ (test_thread_flag(TIF_IA32) ? vm_stack_flags32 : vm_stack_flags) #define VM_STACK_DEFAULT_FLAGS vm_stack_flags (yes, seriously: two different #define's for that thing, with the first one being inside an "#ifdef TIF_IA32") It's possible that it is UML that should just be fixed in this area, but for now let's just undo the (very small) optimization. Reported-by: Randy Dunlap Acked-by: Andrew Morton Cc: Michal Hocko Cc: Richard Weinberger Signed-off-by: Linus Torvalds --- fs/exec.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/exec.c b/fs/exec.c index b54f74f3cd80..97e0d52d72fd 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -277,7 +277,7 @@ static int __bprm_mm_init(struct linux_binprm *bprm) * use STACK_TOP because that can depend on attributes which aren't * configured yet. */ - BUILD_BUG_ON(VM_STACK_FLAGS & VM_STACK_INCOMPLETE_SETUP); + BUG_ON(VM_STACK_FLAGS & VM_STACK_INCOMPLETE_SETUP); vma->vm_end = STACK_TOP_MAX; vma->vm_start = vma->vm_end - PAGE_SIZE; vma->vm_flags = VM_STACK_FLAGS | VM_STACK_INCOMPLETE_SETUP; -- 2.20.1