[PATCH] ix86: fix vDSO build

From: Jan Beulich
Date: Thu Jul 03 2014 - 10:35:19 EST


Relying on static functions used just once to get inlined (and
subsequently have dead code paths eliminated) is wrong: Compilers are
free to decide whether they do this, regardless of optimization level.
With this not happening for vdso_addr() (observed with gcc 4.1.x), an
unresolved reference to align_vdso_addr() causes the build to fail.

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
---
arch/x86/vdso/vma.c | 4 ++++
1 file changed, 4 insertions(+)

--- 3.16-rc3/arch/x86/vdso/vma.c
+++ 3.16-rc3-x86-vdso-build/arch/x86/vdso/vma.c
@@ -62,6 +62,9 @@ struct linux_binprm;
Only used for the 64-bit and x32 vdsos. */
static unsigned long vdso_addr(unsigned long start, unsigned len)
{
+#ifdef CONFIG_X86_32
+ return 0;
+#else
unsigned long addr, end;
unsigned offset;
end = (start + PMD_SIZE - 1) & PMD_MASK;
@@ -83,6 +86,7 @@ static unsigned long vdso_addr(unsigned
addr = align_vdso_addr(addr);

return addr;
+#endif
}

static int map_vdso(const struct vdso_image *image, bool calculate_addr)



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