Re: linux-next: manual merge of the kvm-ppc tree with the powerpc-merge tree

On 11.10.2012, at 11:27, David Howells wrote:

Stephen Rothwell [off-list ref] wrote:
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quoted

I just removed epapr_hcalls.h from the Kbuild file as I am not sure =

how

quoted

it should be broken up.  David, can you have a look at this, please?

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Files should be broken up along around __KERNEL__ conditionals.  If =

there are

no __KERNEL__ conditionals, it is assumed that the file is entirely =

UAPI and

can just be moved.
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The problem appears to be this commit:
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	=

https://github.com/agraf/linux-2.6/commit/4c09029a5639c955fcf6d65205796e4f=
1208aed3

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	From: Liu Yu [off-list ref]
	Subject: KVM: PPC: Add support for ePAPR idle hcall in host =

kernel

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Just makes epapr_hcalls.h part of the userspace API in its entirety by =

this bit

of the patch:
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	+header-y +=3D epapr_hcalls.h
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whilst not adding any __KERNEL__ guards - which is almost certainly =

incorrect.

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At the very least, I would say that the global variable declarations =

need

limiting to kernel space, and thus so do the inline functions as they =

emit

inline assembly to jump somewhere specified by one of the global =

variables

(actually a code array).
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So for manual splitting purposes, I would go with just moving all the =

#defines

prior to the __ASSEMBLY__ guard out to uapi.  Everything within the
__ASSEMBLY__ guard is KABI only by the looks of it.

Do I have to move them to their own header file or can I just #ifdef =
__KERNEL__ around the place where __ASSEMBLY__ starts to the end of the =
file?


Alex