[Qemu-devel] Change of TEXT_OFFSET for multi_v7_defconfig

Jason Gunthorpe jgunthorpe at obsidianresearch.com
Tue Apr 22 10:53:25 PDT 2014


On Tue, Apr 22, 2014 at 06:11:42PM +0100, Russell King - ARM Linux wrote:

> Put another way, if your platform is part of the multi-platform kernel
> then you are *excluded* from being able to use this... unless you hack
> the Kconfig, and then also provide a constant value for PHYS_OFFSET,
> thereby _tying_ the kernel you built to a _single_ platform.

That is exactly right. To get a fixed LMA you must commit to a
non-relocatable kernel image.

Realistically this patch would need to be accompanied by something
that makes ARM_PATCH_PHYS_VIRT optional for multiplatform based on
EXPERT or similar.

The best usecase seems to be to support ELF tooling for low level
debugging activities, a non-relocatable image isn't a blocker for that
case.

Since the patch is a no-op if LOAD_OFFSET isn't set, is there a
downside I don't see?

Thanks,
Jason



More information about the linux-arm-kernel mailing list