x86-64 compile error in 2.6.9-rc1-bk1

If you have CONFIG_SWIOTLB=y (GART_IOMMU=y), you get:

ld: BFD 2.15.90.0.3 20040415 assertion fail ../../bfd/linker.c:619 arch/x86_64/mm/built-in.o(.init.text+0x52a): In function `mem_init':
: undefined reference to `swiotlb_force'
make[1]: *** [.tmp_vmlinux1] Error 1
make: *** [_all] Error 2

This was added in Linus's tree. But I cannot find where swiotlb_force is defined...

diff -Nru a/arch/x86_64/mm/init.c b/arch/x86_64/mm/init.c

@@ -396,6 +400,8 @@

        return 0;

}

+extern int swiotlb_force;
+
static struct kcore_list kcore_mem, kcore_vmalloc, kcore_kernel, kcore_modules, kcore_vsyscall;

@@ -405,7 +411,10 @@

        int tmp;

#ifdef CONFIG_SWIOTLB
- if (!iommu_aperture && end_pfn >= 0xffffffff>>PAGE_SHIFT)
+ if (swiotlb_force)
+ swiotlb = 1;
+ if (!iommu_aperture &&
+ (end_pfn >= 0xffffffff>>PAGE_SHIFT || force_iommu))

               swiotlb = 1;
        if (swiotlb)
                swiotlb_init();

It is defined in a ia64 specific file (believe it or not) The change should go in as soon as Linus pulls the IA64 update from Tony Luck.

For now you can just comment out the if.

-Andi