Re: [PATCH v1 2/9] asm-generic: move parts of Arm's asm/kernel.h to asm-generic

[Jan Beulich <jbeulich@xxxxxxxx>]

On 03.02.2025 16:34, Oleksii Kurochko wrote:
> 
> On 1/27/25 12:15 PM, Jan Beulich wrote:
>> On 08.01.2025 12:13, Oleksii Kurochko wrote:
>>> Move the following parts to asm-generic with the following changes:
>>> - struct kernel_info:
>>>    - Create arch_kernel_info for arch specific kernel information.
>>>      At the moment, it contains domain_type for Arm.
>>>    - Rename vpl011 to vuart to have more generic name suitable for other 
>>> archs.
>>>    - s/phandle_gic/phandle_intc to have more generic name suitable for other
>>>      archs.
>>>    - Make text_offset of zimage structure available for RISCV_64.
>>> - Wrap by `#ifdef KERNEL_INFO_SHM_MEM_INIT` definition of 
>>> KERNEL_SHM_MEM_INIT
>>>    and wrap by `#ifndef KERNEL_INFO_INIT` definition of KERNEL_INFO_INIT to 
>>> have
>>>    ability to override KERNEL_INFO_SHM_MEM_INIT for arch in case it doesn't
>>>    want to use generic one.
>>> - All other parts are left as is from Arm's asm/kernel.h
>>>
>>> Because of the changes in struct kernel_info the correspondent parts of 
>>> Arm's
>>> code are updated.
>>>
>>> As part of this patch the following clean up happens:
>>> - Drop asm/setup.h from asm/kernel.h as nothing depends from it.
>>>    Add inclusion of asm/setup.h for a code which uses device_tree_get_reg() 
>>> to
>>>    avoid compilation issues for CONFIG_STATIC_MEMORY and CONFIG_STATIC_SHM.
>>>
>>> Signed-off-by: Oleksii Kurochko<oleksii.kurochko@xxxxxxxxx>
>> I question that what is being moved qualifies for asm-generic, an in 
>> particular
>> for a header named kernel.h. Some of what you move may make sense to move to
>> dom0less-build.h instead. But everything that doesn't fit there needs to find
>> a different home, imo.
> 
> It doesn't clear what then should be in kernel.h, I did in this way to not 
> have a problem with header inclusion
> during the build of Arm.
> 
> Definitions DOM0LESSS_* could be moved to dom0less-build.h, all other doesn't 
> really connected only to dom0less feature
> and could be re-used for dom0 so it seems like it should leave in a separate 
> header ( if kernel.h isn't good for it ).
> 
> Probably kernel.h shouldn't leave in asm-generic as nothing architecture 
> specific is in it,

Well, kernel.h under asm-generic/ is somewhat odd in the first place.

> but on the other hand, will it
> be okay to have something in xen/include if it isn't supported by all 
> architectures?

It can be okay; it depends on a number of factors.

Jan